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Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia
Vaccine xxx (xxxx) xxx
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Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia Elisa Lai a,⇑, Hao Yi Tan b, Mohana Kunasekaran a, Abrar Ahmad Chughtai b, Mallory Trent a, Christopher Poulos b,c, C. Raina MacIntyre a,d a
Biosecurity Program, The Kirby Institute, Faculty of Medicine, University of New South Wales, Sydney, Australia School of Public Health and Community Medicine, Faculty of Medicine, University of New South Wales, Sydney, Australia Research and Aged Care Clinical Services, HammondCare, Australia d College of Public Service and Community Solutions, Arizona State University, AZ, USA b c
a r t i c l e
i n f o
Article history: Received 24 June 2019 Received in revised form 13 December 2019 Accepted 5 January 2020 Available online xxxx Keywords: Aged care workers Influenza vaccine Coverage Long-term care facilities Nursing homes Occupational health
a b s t r a c t Aged care facilities (ACFs) are residential communities with a concentration of vulnerable individuals with increased risk of severe influenza infection and complications such as outbreaks, hospitalisations and deaths. Aged care workers (ACW) are potential sources of influenza introduction and transmission in ACFs. Little is known about vaccine uptake among ACW. This study aimed to measure the vaccine uptake rate among Australian ACW and evaluate the demographic determinants of uptake during the influenza season of 2018. 146 ACWs were recruited from 7 facilities of a multisite aged care provider in Sydney. ACWs completed a questionnaire regarding their demographic, occupational and vaccination status. Vaccine coverage was calculated and variables were examined against their 2018 influenza vaccination status in statistical analysis. ACWs in our study were predominantly from a non-health occupational background with a large proportion of migrant workers (56%, 75/134). Vaccine coverage in 2018 was 48% (65/135). The strongest determinants of vaccine uptake were previous year vaccination history (Odds Ratio [OR] 10.49, 95% CI 3.33–33.10), workplace immunisation programs for employees (OR 7.87, 95% CI 2.47–25.10), casual work as employment status (OR 0.14, 95% CI 0.02–0.77), and presence of comorbidities (OR 4.04, 95% CI 1.23– 13.32). ACW are a unique and understudied group who are critical to infection control in ACFs. Few ACWs have formal health training, and many are migrants who may lack access to subsidised health care and face out of pocket costs for vaccination. Vaccine coverage among ACW were below recommended levels. Provision of influenza vaccine for staff in workplaces is highly effective in raising vaccine coverage amongst ACWs. More research on the aged care sector workforce is needed in order to evaluate the determinants of vaccine uptake among Australian ACWs. Ó 2020 Elsevier Ltd. All rights reserved.
1. Introduction Seasonal influenza causes considerable morbidity and mortality within aged care facilities (ACFs) in which the risk of outbreaks, hospitalisations and deaths are well documented [1–3]. Individuals over the age of 65 account for 90% of influenza deaths due to increased risk factors such as immunosenescence, malnutrition and underlying chronic illnesses [4,5]. Older adults have increased viral load and prolonged viral shedding, thus increasing illness ⇑ Corresponding author at: Kirby Institute, Faculty of Medicine, University of New South Wales, Wallace Wurth Building Room 644, Kensington, NSW 2052, Australia. E-mail address: [email protected] (E. Lai).
severity, ease of transmission and outbreaks [6,7]. Transmission is further intensified in the institutionalised environment of an ACF where these vulnerable individuals share carers and common spaces [4,6,7]. While immunising residents is the mainstay of primary intervention against influenza outbreaks within ACFs, outbreaks still occur despite high uptake rates [8–10]. Furthermore, a single exposure of influenza virus to older people increases the risk of hospitalisation and death [11]. Up until recently, aged care worker (ACW) influenza vaccination has been relatively underemphasized as an influenza prevention strategy in the ACF setting. Assuming that ACWs are healthy adults, the seasonal inactivated quadrivalent vaccine can have a vaccine effectiveness as high as 62% even
https://doi.org/10.1016/j.vaccine.2020.01.004 0264-410X/Ó 2020 Elsevier Ltd. All rights reserved.
Please cite this article as: E. Lai, H. Y. Tan, M. Kunasekaran et al., Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia, Vaccine, https://doi.org/10.1016/j.vaccine.2020.01.004
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with poorly matched components [12]. The influenza vaccines have demonstrated effectiveness of 59% reduction in laboratory proven influenza and 47–73% reduction in influenza-like illness in healthy non-elderly health care workers [13–15] and evidence shows that vaccination of healthcare workers can reduce serologically confirmed influenza by nearly 90% in those vaccinated [16]. Hence, aside from minimising staff shortages during efforts to control outbreaks, vaccination of ACWs may also provide indirect protection for the residents under their care [17]. ACWs have repeated and prolonged contact with residents but are also widely dispersed in the community outside of work hours, thus ACWs may act as vectors in influenza introduction into the ACF, and facilitate transmission from resident to resident [18]. Poor vaccine uptake among ACWs has been shown to contribute to ACF outbreaks, whereas a high vaccine uptake has been associated with a decrease in resident mortality during influenza season [17,19–23]. In Australia, annual influenza immunisation is currently not mandatory for ACWs although Australian guidelines recommend a 95% coverage rate per facility [24,25]. A 2003 study conducted in Australian Capital Territory examined the vaccination rate of ACWs and demonstrated only a 28% uptake among staff [26]. Overseas studies show an average 50% vaccination rate [7,22–27]. Identifying the predictive factors of influenza vaccine uptake may facilitate the enactment of effective measures to raise vaccine uptake and reduce outbreaks among ACFs. Therefore, this study aimed to determine influenza vaccine uptake rate among ACWs in Australia and examine the demographic predictors of vaccine uptake.
2. Methods 2.1. Study design An observational epidemiologic study was conducted among ACWs of a multisite (4 sites, A, B, C, D, 8 independent facilities) aged care provider in Sydney, Australia. For the purposes of this study, an ‘ACW’ was defined as any employed staff who have any form of direct or indirect involvement with the delivery of care, support and administrative services to residents. Of all the employed staff (668) that were invited to participate, 146 staff agreed, were recruited and completed a questionnaire which collected information on the vaccination status of the staff and other background medical and demographic information during the months of March to July 2018. Teams of researchers were invited by the managers to present the study during staff meetings and handovers to recruit participants who would provide consent and fill in the questionnaire during that time. Depending on the preference of the manager, information regarding the study was presented to the staff by a member of the research team, the manager, or a combination of both. A separate survey was completed by respective managers of each facility which collected baseline data regarding employment and institutional policies on influenza vaccination programs for staff.
2.3. Covariates We included age [27], sex [28], ethnicity [29], birth country [30], marital status [31], household arrangement [32], education [32], employment history [32], smoking and alcohol history [33,34], medical history [35] and previous vaccination history [36] as covariates in our analysis due to potential confounding effects identified in the literature. Age was categorized as < 40 years or 40 years, as the median age was close to 40, and sex (male or female) was determined by medical record review. Ethnicity was categorized as Caucasian and ‘‘other” while country of birth was categorized as Australia and ‘‘other”. Marital status was considered as three categories: never married, married and ‘‘other”. Household arrangement was explored by whether children or older adults were in the household. These two variables were dichotomized (present or not) to create a consistent approximate representation of household arrangement across all the participants. Highest level of education was pooled into two categories: ‘university degree’, which includes undergraduate and post graduate qualifications, and ‘other’ which indicates a level of education below university education (e.g. school certificate, higher school certificate, trade certificate or diploma). ACWs were further categorised into ‘daily carer’ and ‘other’ depending on their frequency and quality of interaction with residents. ‘Daily carers’ included age carers, nurse’ aides and specialised dementia carers, all of whom are directly involved in the day-to-day care of the resident. ‘Others’ indicated ACWs who provide any form of support or service to the residents on less frequent basis, such as the registered nurse, pastoral care, manager, workplace trainer, caterer, and administrative staff. Participating facilities were also categorised based on the type of vaccination program offered to staff. Site B and Site D offered free onsite vaccine services for staff while the facilities at Site A and Site C only offered reimbursements for vaccines acquired from private general practitioners or local pharmacies. Smoking status was defined as a categorical variable where current and those who previously smoked (ex-smokers) were compared against those who were non-smokers. Comorbidities and previous year vaccination status were binary variables. We conducted a logistic regression analysis of the associations between the variables in Table 3 and influenza vaccination status in 2018. These variables were examined against the influenza vaccination status in 2018 to determine statistical significance in bivariate analyses. Those variables that were statistically significant were included in the multivariate model. 2.4. Data analysis All data were collated in a secured, private drive and then manually entered into Microsoft Access 2013 and analysed in IBM SPSS Statistics 25. All cases with missing data on the 2018 influenza vaccination outcome were excluded from analysis. Overall influenza vaccination rate was calculated and descriptive analysis was
Table 1 Participation rate by facilities with respondents.
2.2. Outcome measures Vaccine uptake was defined as the percentage of ACWs who received an influenza vaccine during the months of March to July 2018 (recruitment period). Participants who were not sure if they were going to be vaccinated were classified as ‘‘undecided” and those who were recruited before the annual influenza vaccine were announced and hence had not received the current influenza vaccine were followed up at the end of the recruitment period and the final vaccination status was recorded.
Facility
No. Employed
No. Consented
Participation rate
Site A Facility Facility Facility Site B Site C Facility Facility Site D Total
296 123 38 135 115 187 108 79 70 668
81 43 7 31 32 15 14 1 18 146
27% 35% 18% 23% 28% 8% 13% 1% 26% 22%
A1 A2 A3
C1 C2
Please cite this article as: E. Lai, H. Y. Tan, M. Kunasekaran et al., Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia, Vaccine, https://doi.org/10.1016/j.vaccine.2020.01.004
E. Lai et al. / Vaccine xxx (xxxx) xxx
conducted for each variable against the rates of 2018 influenza vaccination. Table 1 displays the rates of vaccination by site. Total completed responses were used instead of total number of participants to calculate proportions for each variable due to incomplete questionnaires (refer to Table 2 for denominators). Univariate analysis included chi square tests, or binary logistic regression with p values < 0.05 considered statistically significant. Odds ratios (OR) and 95% confidence interval (CI) were calculated. Multiple logistic regression was used to examine the predictive indicators of influenza vaccination uptake among ACWs. 3. Ethics approval This research was reviewed and approved by The University of New South Wales Human Research Ethics Committee (HREC) under the project number HC17996. Approval was also sought and obtained from the ethics board of the aged care provider under
Table 2 Demographic characteristics (total n = 135). Variable Age, years Mean (S.D.) <40 40 Gender Female Male Ethnicity Caucasian Other Birth Country Australia Other Marital status Never married Married Other* Child(ren) in household Present None Older individual(s) in household Present None Education University degree Other Occupation Daily carer Other Employment status Full time Part time Casual work Workplace vaccination policy Free onsite vaccine service Private GP with reimbursement Smoking status Current/ex-smoker Non-smoker Comorbiditiesy Present None Previous year vaccination Vaccinated Not vaccinated Influenza vaccination 2018 Vaccinated Not vaccinated
No.
Percent
75/134 59/134
37.9 (±13.9) 56.0 44.0
114/135 21/135
84.4 15.6
56/130 74/130
43.1 56.9
59/134 75/134
44.0 56.0
42/134 74/134 18/134
31.3 52.2 13.3
47/134 87/134
35.1 64.9
13/124 111/124
10.5 89.5
66/135 69/135
48.9 51.1
111/131 20/131
84.7 15.3
35/134 79/134 20/134
26.1 59.0 14.9
48/135 87/135
35.6 64.5
41/134 93/134
30.6 69.4
36/134 98/134
26.9 73.1
43/127 84/127
33.9 66.1
65/135 70/135
48.1 51.9
*Other includes: divorced (n = 14), widowed (n = 1), other (unspecified) (n = 3). Comorbidities include: asthma, cardiovascular disease, respiratory disease, diabetes, and ‘others’. Denominator varied according to the total number of responses for that variable.
y
3
the project code R153. Confidentiality of the participants and their data were ensured by the removal of all identifications prior to analysis.
4. Results The questionnaire was completed by 146 ACWs across the four sites. Among the 8 facilities which had agreed to participate, there were no participants from Facility A4, which was subsequently excluded from data analysis to avoid the skewing of results. Among the 4 sites (7 facilities), response rate varied with an overall participation rate of 22% (range 8–28%) (Table 1). The information regarding the characteristics of those that did not participate in the study was not available and the results obtained could be overestimating the vaccine uptake. As those who are not likely to participate in studies are also not likely to be vaccinated due to having similar barriers as reflected in the literature [37–39]. We can assume that the actual uptake could be lower if more respondents from facilities with no free access to the vaccine participated. Baseline data provided from the managers showed that the mean number of staff employed per site was 175 (range 70– 327). The age of the participants ranged from 18 to 69 with a male to female ratio of 1:5. Participants reported birth countries from all continents: Oceania (n = 67), Asia (n = 49), Africa (n = 8), Europe (n = 6), South America (n = 3) and North America (n = 1). Only 44% of respondents were born in Australia and 43% identified as Caucasian. There was found to be a large concentration of migrant workers from Asian countries, especially Nepal (19%) and Philippines (9%). The majority were married (52%) and most were residing in households with no children (65%) or older individuals over the age of 65 (90%). Almost half the respondents held university qualifications such as a bachelor or post-graduate degree (49%). The majority of respondents provided daily care for residents (85%) and the range of employment type undertaken were: aged carers (85%), nursing (7%), managerial, training and administrative staff (6%), and others (2%). The employment characteristics of participating staff were examined and compared to the baseline data collected from respective managers. There were found to be an overrepresentation of aged carers in our study and fewer registered nurses. The majority of the respondents were employed on a part time basis (59%) compared to full time (26%) and casual work (15%). Most respondents were non-smokers (69%) and a large majority were without chronic illnesses (73%). This could have introduced a bias as it may not have been representative of the ACW in the facilities as those who were health conscious were more likely to also be willing to participate in the study [39]. Results from the questionnaires also demonstrated an increased in influenza uptake from 2017 (34%) to 2018 (48%) (Table 2). In univariate analysis, five predictors were significantly associated with influenza vaccine uptake in 2018: previous year’s vaccination, workplace policy on influenza vaccination among staff, presence of comorbidities, employment status and marital status. These variables remained significant in multivariate analysis, except marital status (Table 3). Previous influenza vaccine uptake had the strongest association, and respondents who vaccinated in 2017 were significantly more likely than those who did not, to vaccinate in 2018 (OR 10.49, 95% confidence interval [CI] 3.33–33.10). The odds of vaccination amongst staff in facilities which offered free onsite vaccine services were 8 times greater than the odds of vaccination amongst staff in facilities which only offered reimbursements for the cost of vaccines acquired from private physicians or from local pharmacies (OR 7.87, 95% CI 2.47–25.10). Respondents with underlying chronic
Please cite this article as: E. Lai, H. Y. Tan, M. Kunasekaran et al., Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia, Vaccine, https://doi.org/10.1016/j.vaccine.2020.01.004
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E. Lai et al. / Vaccine xxx (xxxx) xxx
Table 3 Predictors of influenza vaccine uptake. Variable Age, years <40 40 Gender Male Female Ethnicity Other Caucasian Birth country Other Australia Marital status Never married Married Other* Child(ren) in household None Present Older individual(s) in household None Present Education Other University degree Occupation Other Daily carer Employment status Full time Part time Casual work Workplace vaccination policy Private GP with reimbursement Free onsite vaccine service Smoking status Non-smoker Current/ex-smoker Comorbiditiesy No Yes Previous year vaccination No Yes
Proportion vaccinated
Rate (%)
Univariate analysis (OR, 95% CI)
Multivariate analysis (OR, 95% CI)
32/75 32/59
42.7 54.2
Ref. 1.59 (0.80–3.17)
Ref. 0.64 (0.20–2.02)
11/21 54/114
52.4 47.4
Ref. 0.82 (0.32–2.08)
Ref. 0.39 (0.11–1.36)
31/74 31/56
41.9 55.4
Ref. 1.72 (0.85–3.47)
Ref. 2.79 (0.83–9.39)
36/75 28/59
48.0 47.5
15/42 35/74 14/18
35.7 47.3 77.8
Ref. 0.98 (0.49–1.94) Ref. 1.61 (0.74–3.52) 6.30 (1.76–22.61)
Ref. 1.67 (0.54–5.39) 2.75 (0.43–1.54)
43/87 22/47
49.4 46.8
Ref. 0.90 (0.44–1.83)
50/111 8/13
45.0 61.5
Ref. 1.95 (0.60–6.34)
35/69 30/66
50.7 45.5
Ref. 0.81 (0.41–1.59)
Ref. 1.28 (0.42–3.94)
10/20 52/111
50.0 46.8
Ref. 0.88 (0.34–2.29)
Ref. 2.82 (0.65–12.27)
21/35 38/79 5/20
60.0 48.1 25.0
Ref. 0.62 (0.28–1.39) 0.22 (0.07–0.75)
Ref. 0.30 (0.09–0.99) 0.14 (0.02–0.77)
32/87 33/48
36.8 68.8
Ref. 3.78 (1.79–8.00)
Ref. 7.87 (2.47–25.10)
44/93 20/41
47.3 48.8
Ref. 1.06 (0.51–2.21)
Ref. 0.37 (0.11–1.23)
42/98 23/36
42.9 63.9
Ref. 2.36 (1.07–5.19)
Ref. 4.04 (1.23–13.32)
31/84 32/43
36.9 74.4
Ref. 4.97 (2.20–11.25)
Ref. 10.49 (3.33–33.10)
*Other includes: divorced (n = 14), widowed (n = 1), other (unspecified) (n = 3). y Comorbidities include: asthma, cardiovascular disease, respiratory disease, diabetes, and ‘others’. Denominator varied according to the total number of responses for that variable. Bolded text indicates statistically significant (p values < 0.05).
illness had greater odds of vaccination in 2018 (OR 4.04, 95% CI 1.23–13.32). Compared to full time workers, part timer workers (OR 0.30, 95% CI 0.09–0.99) and casual workers (OR 0.14, 95% CI 0.02–0.77) were less likely to be vaccinated (Table 3). 5. Discussion Our study found a 20% higher uptake than recorded in a 2003 cross-sectional survey conducted in the Australian Capital Territory (28%), although it falls far below the 95% coverage recommended by Communicable Diseases Network of Australia (CDNA) [25–26]. This study population comprised a large proportion of migrants (56%). The strongest determinants of vaccine uptake among ACWs were previous year vaccination history (OR 10.49, 95% CI 3.33–33.10), workplace immunisation programs for employees (OR 7.87, 95% CI 2.47–25.10), casual work as employment status (OR 0.14, 95% CI 0.02 – 0.77), and presence of comorbidities (OR 4.04, 95% CI 1.23–13.32). Our results are consistent with international studies which average at a 50% vaccination rate [23,40–45]. However, there were large discrepancies in uptake rate between facilities [40]. Perceived
barriers to the influenza vaccine include accessibility and cost, beliefs about efficacy and negative effects, such as scepticism towards staff influenza vaccination and workplace attitudes towards adherence guidelines and recommendations [46]. As such, facility-level differences such as management policies, staff education and workplace immunization programs would also contribute to the vaccination uptake rate [41,42,47–49]. Examples of influenza immunisation programs include: provision of vaccine, tracking vaccine uptake, reminder systems, education, and the implementation of an opt-out policy where a written declination form is required for non-immunisation which have been shown to be effective in raising ACW vaccine uptake [41]. Consistent with the literature, our findings suggest that workplace provision of influenza vaccination plays an important part in the decision to immunise, with higher vaccination rates in facilities providing onsite vaccination. The study population included a large proportion of migrant workers staying in Australia, anecdotally holding working visas rather than permanent resident visas, although we did not collect data on this. Anecdotally, ACWs reported not having Medicare access and having to meet out of pocket costs for vaccination.
Please cite this article as: E. Lai, H. Y. Tan, M. Kunasekaran et al., Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia, Vaccine, https://doi.org/10.1016/j.vaccine.2020.01.004
E. Lai et al. / Vaccine xxx (xxxx) xxx
As Medicare is offered only to Australian and New Zealand citizens and permanent visa holders, migrants on working visas are not eligible to receive government subsidised healthcare privileges which would cover the consultation fees of a physician [50]. In such cases, an ACW on a working visa seeking vaccination from their physician would be required to pay out of pocket the cost of both the consultation and the vaccine. The out of pocket cost of vaccination may be a significant disincentive for such ACWs, even if reimbursement is offered by the employer. Therefore, free, onsite vaccine services are able to overcome inconvenience, cost and accessibility for all ACWs and reinforce the employer’s support for immunisation [26,49,51,52]. In the absence of such services, ethnic disparities among HCWs have been shown to be reduced through education [29]. Living with underlying chronic illnesses has also been shown to be a positive predictor of vaccination status likely due to increased health awareness. A patient’s decision making is significantly influenced by their physicians, therefore increased interaction with their physicians may lead to increased opportunities for health education and promotion of influenza vaccination [53]. The decision to vaccinate is affected by several factors including trust or mistrust in the efficacy of modern medicine, side-effects from previous vaccination, perceived risk-benefit ratio associated with influenza and concerns that the vaccine could exacerbate underlying conditions such as asthma [54,55]. In general, influenza vaccination is an effective public health intervention in preventing seasonal influenza infection, hospitalization and mortality. In a systematic review, Restivo and colleagues concluded that influenza vaccination of HCWs is the most effective public health strategies for preventing nosocomial influenza transmission and reducing ILI mortality among elderly and high-risk patients, as well as for minimizing absenteeism during annual epidemics [56]. Hence, mandatory vaccination could be a potential method of targeting low vaccine uptake in health care settings in Australia. In Australia, there have been initiatives to protect vulnerable patient groups via high vaccine uptake among healthcare workers evident in the new policies regarding mandatory influenza vaccination in hospital wards with immunocompromised patients such as the ante-, peri-, post-natal wards, oncology and transplant wards, and all intensive care units [57]. Aged care, however, is not a health care setting, and nor are residents ‘‘patients.” Although people over the age of 65 are recognised to be a high-risk population, it is not currently compulsory for ACWs to receive the seasonal influenza vaccine. Since April 2018, it has been compulsory for all Australian ACFs to recommend influenza immunization to their staff and increase awareness related to it [58]. According to baseline information of each facility provided by the managers, all ACWs, regardless of facility and location, were ‘encouraged’, via meetings and posters in common areas, to get the annual influenza vaccination. However, due to the sensitive nature of the topic of vaccination, there could have been some hesitancy to explicitly advocate for immunisation. This highlights the need for education and advocacy related to influenza vaccination. Positive determinants of vaccine uptake include: the perception of increased risk of infection as an ACW and knowledge of the effectiveness of vaccines in protecting themselves, the residents and their family; and the awareness of employee recommendations and programs regarding influenza vaccination for ACW [26,51,52,59]. If education regarding influenza vaccination is not provided through workplace training or advocacy, many ACWs will have misperceptions about influenza vaccine. Another occupational characteristic which play a role in vaccine uptake among ACWs is employment status. Compared to casual and part-time workers, full-time ACWs typically have the longest cumulative work hours per week (i.e. 35–40+ hours) and greater permanency in their job [60]. These factors may heighten the sense
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of duty of care and thereby compel full-time ACWs to vaccinate in order to extend protection to the residents under their care. Alternatively, increased contact with residents may increase the perception of the risk of infection, motivating ACWs to vaccinate for the protection of themselves and their contacts. The delivery of vaccination services is complicated by variations in staff working hours and with the difficulty of capturing shift-workers who are not able to come in at other times outside their shifts as they could be working in other sites [61]. Given the largely casual and parttime nature of the Australian ACFs workforce, vaccination policies which target staff are not as well-researched as those working in hospital. More research is needed to understand this difference and improve implementation of workplace implementation policies. Thomas and colleagues concluded in their review of four cluster randomized control trials and one cohort study of influenza vaccine in HCW working in ACFs, that there was no conclusive evidence of benefit of healthcare worker vaccination programmes to people over the age of 60 who live in ACFs [62]. Therefore, the emphasis on influenza vaccination and addressing organizational barriers to vaccine uptake in ACFs, does not negate the need for the implementation of other non-vaccination associated workplace strategies regarding the management of influenza. Education has a role in not only improving influenza vaccine uptake but also in improving influenza control and management overall [49]. The strengths of this study is in our definition of ACW which encompasses all groups of workers within an ACF, as opposed to only focusing on care staff. By doing so, we acknowledge that any person interacting within both the ACF and the wider community have the potential to act as a vector for the influenza virus. A caveat of this study is the low response rate, despite multiple channels used to make staff aware of the study. Shift work and lack of time was cited as a factor. Although the study had been designed in collaboration with representatives of the aged care provider, there was little incentive for the staff to participate and volunteer their time. Low participation rate of 22% not only weakens the power of this study but increases the risk of bias. There could have been preferential participation by those with positive opinions regarding immunisation which may result in an overestimation of vaccine uptake. Recall bias might be present as the completion of the demographic, occupational and medical details were selfreported. Although this was mitigated by consented access to the participant’s general practitioner, with the introduction of a new pathway to influenza vaccination through local pharmacies and a more systematic collection of information through the Australian Immunization Register, gaps in keeping proper records will be further reduced. Conclusions drawn from this dataset have limited generalizability due to low response rates and the small number of ACFs involved, although attempts have been made to address bias. Despite the challenges of conducting studies in the ACF setting and limitations of the findings, staff vaccination rates are well below recommended levels and should be addressed in future policy.
6. Conclusion The Australian aged care workforce is a unique occupational group, with over half being migrants and many being ineligible for government subsidised healthcare. Vaccine uptake among ACWs remains suboptimal, but provision of workplace vaccination can overcome this barrier. We recommend more research into ACFs and the ACW workforce, looking specifically at their needs and the barriers to vaccination. By addressing issues of misconcep-
Please cite this article as: E. Lai, H. Y. Tan, M. Kunasekaran et al., Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia, Vaccine, https://doi.org/10.1016/j.vaccine.2020.01.004
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tions, unawareness, cost and accessibility, higher vaccine uptake could be achieved. Ethical statement This manuscript has not been published previously in print or electronic format and is not under consideration by another publication or electronic medium. The Corresponding Author has the right to grant on behalf of all authors and does grant on behalf of all authors, an exclusive licence on a worldwide basis to the BMJ Publishing Group Ltd to permit this article (if accepted) to be published in BMJ editions and any other BMJPGL products and sublicenses such use and exploit all subsidiary rights, as set out in our licence. CRediT authorship contribution statement Elisa Lai: Writing - original draft, Data collection, Formal analysis, Investigation. Hao Yi Tan: Data collection, Investigation. Mohana Kunasekaran: Data collection, Writing - review & editing, Investigation, Project administration. Abrar Ahmad Chughtai: Data collection, Supervision, Formal analysis. Mallory Trent: Data collection, Investigation, Project administration, Data curation. Christopher Poulos: Conceptualization and site supervision. C. Raina MacIntyre: Conceived and designed the study, supervised study analysis, contributed to data cio writing. Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: This work was supported by a grant from the NHMRC Centre of Research Excellence in Integrated Systems for Epidemic Response (ISER) under the grant ID 1107393. Professor C Raina MacIntyre is supported by a NHMRC Principal Research Fellowship of grant ID 1137582. Acknowledgements The authors thank the staff at the ACFs for their assistance with the study. Their help has been greatly valued. References [1] Australian government department of health. 2017 Influenza season in Australia: A summary from the national influenza surveillance committee. Canberra: Department of Health; 2017 22 November 2017. [2] Newall AT, Viboud C, Wood JG. Influenza-attributable mortality in Australians aged more than 50 years: a comparison of different modelling approaches. Epidemiol Infect 2010;138(6):836–42. [3] Newall AT, Wood JG, MacIntyre CR. Influenza-related hospitalisation and death in Australians aged 50 years and older. Vaccine 2008;26(17):2135–41. [4] Castilla J, Cia F, Zubicoa J, Reina G, Martinez-Artola V, Ezpeleta C. Influenza outbreaks in nursing homes with high vaccination coverage in Navarre, Spain, 2011/12. Euro Surveillance: Bulletin Europeen sur les maladies transmissibles = European Communicable Disease Bulletin 2012;17(14). [5] Australian Government Department of Health. 2017 Influenza season in Australia a summary from the National Influenza Surveillance Committee Canberra2017 [updated 22 November 2017. Available from: https://www1. health.gov.au/internet/main/publishing.nsf/Content/ 097F15A91C05FBE7CA2581E20017F09E/$File/2017-season-summary22112017.pdf. [6] Goodwin K, Viboud C, Simonsen L. Antibody response to influenza vaccination in the elderly: A quantitative review. Vaccine 2006;24(8):1159–69. [7] Leekha S, Zitterkopf NL, Espy MJ, Smith TF, Thompson RL, Sampathkumar P. Duration of influenza a virus shedding in hospitalized patients and implications for infection control. Infect Control Hosp Epidemiol 2007;28 (9):1071–6. [8] Tennant E, Fletcher S, Kakar S, Najjar Z, Lord H, Clark P, et al. Factors associated with adverse outcomes during influenza outbreaks in aged care facilities. Aust NZ J Public Health 2019.
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Please cite this article as: E. Lai, H. Y. Tan, M. Kunasekaran et al., Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia, Vaccine, https://doi.org/10.1016/j.vaccine.2020.01.004
Contents lists available at ScienceDirect
Vaccine journal homepage: www.elsevier.com/locate/vaccine
Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia Elisa Lai a,⇑, Hao Yi Tan b, Mohana Kunasekaran a, Abrar Ahmad Chughtai b, Mallory Trent a, Christopher Poulos b,c, C. Raina MacIntyre a,d a
Biosecurity Program, The Kirby Institute, Faculty of Medicine, University of New South Wales, Sydney, Australia School of Public Health and Community Medicine, Faculty of Medicine, University of New South Wales, Sydney, Australia Research and Aged Care Clinical Services, HammondCare, Australia d College of Public Service and Community Solutions, Arizona State University, AZ, USA b c
a r t i c l e
i n f o
Article history: Received 24 June 2019 Received in revised form 13 December 2019 Accepted 5 January 2020 Available online xxxx Keywords: Aged care workers Influenza vaccine Coverage Long-term care facilities Nursing homes Occupational health
a b s t r a c t Aged care facilities (ACFs) are residential communities with a concentration of vulnerable individuals with increased risk of severe influenza infection and complications such as outbreaks, hospitalisations and deaths. Aged care workers (ACW) are potential sources of influenza introduction and transmission in ACFs. Little is known about vaccine uptake among ACW. This study aimed to measure the vaccine uptake rate among Australian ACW and evaluate the demographic determinants of uptake during the influenza season of 2018. 146 ACWs were recruited from 7 facilities of a multisite aged care provider in Sydney. ACWs completed a questionnaire regarding their demographic, occupational and vaccination status. Vaccine coverage was calculated and variables were examined against their 2018 influenza vaccination status in statistical analysis. ACWs in our study were predominantly from a non-health occupational background with a large proportion of migrant workers (56%, 75/134). Vaccine coverage in 2018 was 48% (65/135). The strongest determinants of vaccine uptake were previous year vaccination history (Odds Ratio [OR] 10.49, 95% CI 3.33–33.10), workplace immunisation programs for employees (OR 7.87, 95% CI 2.47–25.10), casual work as employment status (OR 0.14, 95% CI 0.02–0.77), and presence of comorbidities (OR 4.04, 95% CI 1.23– 13.32). ACW are a unique and understudied group who are critical to infection control in ACFs. Few ACWs have formal health training, and many are migrants who may lack access to subsidised health care and face out of pocket costs for vaccination. Vaccine coverage among ACW were below recommended levels. Provision of influenza vaccine for staff in workplaces is highly effective in raising vaccine coverage amongst ACWs. More research on the aged care sector workforce is needed in order to evaluate the determinants of vaccine uptake among Australian ACWs. Ó 2020 Elsevier Ltd. All rights reserved.
1. Introduction Seasonal influenza causes considerable morbidity and mortality within aged care facilities (ACFs) in which the risk of outbreaks, hospitalisations and deaths are well documented [1–3]. Individuals over the age of 65 account for 90% of influenza deaths due to increased risk factors such as immunosenescence, malnutrition and underlying chronic illnesses [4,5]. Older adults have increased viral load and prolonged viral shedding, thus increasing illness ⇑ Corresponding author at: Kirby Institute, Faculty of Medicine, University of New South Wales, Wallace Wurth Building Room 644, Kensington, NSW 2052, Australia. E-mail address: [email protected] (E. Lai).
severity, ease of transmission and outbreaks [6,7]. Transmission is further intensified in the institutionalised environment of an ACF where these vulnerable individuals share carers and common spaces [4,6,7]. While immunising residents is the mainstay of primary intervention against influenza outbreaks within ACFs, outbreaks still occur despite high uptake rates [8–10]. Furthermore, a single exposure of influenza virus to older people increases the risk of hospitalisation and death [11]. Up until recently, aged care worker (ACW) influenza vaccination has been relatively underemphasized as an influenza prevention strategy in the ACF setting. Assuming that ACWs are healthy adults, the seasonal inactivated quadrivalent vaccine can have a vaccine effectiveness as high as 62% even
https://doi.org/10.1016/j.vaccine.2020.01.004 0264-410X/Ó 2020 Elsevier Ltd. All rights reserved.
Please cite this article as: E. Lai, H. Y. Tan, M. Kunasekaran et al., Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia, Vaccine, https://doi.org/10.1016/j.vaccine.2020.01.004
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with poorly matched components [12]. The influenza vaccines have demonstrated effectiveness of 59% reduction in laboratory proven influenza and 47–73% reduction in influenza-like illness in healthy non-elderly health care workers [13–15] and evidence shows that vaccination of healthcare workers can reduce serologically confirmed influenza by nearly 90% in those vaccinated [16]. Hence, aside from minimising staff shortages during efforts to control outbreaks, vaccination of ACWs may also provide indirect protection for the residents under their care [17]. ACWs have repeated and prolonged contact with residents but are also widely dispersed in the community outside of work hours, thus ACWs may act as vectors in influenza introduction into the ACF, and facilitate transmission from resident to resident [18]. Poor vaccine uptake among ACWs has been shown to contribute to ACF outbreaks, whereas a high vaccine uptake has been associated with a decrease in resident mortality during influenza season [17,19–23]. In Australia, annual influenza immunisation is currently not mandatory for ACWs although Australian guidelines recommend a 95% coverage rate per facility [24,25]. A 2003 study conducted in Australian Capital Territory examined the vaccination rate of ACWs and demonstrated only a 28% uptake among staff [26]. Overseas studies show an average 50% vaccination rate [7,22–27]. Identifying the predictive factors of influenza vaccine uptake may facilitate the enactment of effective measures to raise vaccine uptake and reduce outbreaks among ACFs. Therefore, this study aimed to determine influenza vaccine uptake rate among ACWs in Australia and examine the demographic predictors of vaccine uptake.
2. Methods 2.1. Study design An observational epidemiologic study was conducted among ACWs of a multisite (4 sites, A, B, C, D, 8 independent facilities) aged care provider in Sydney, Australia. For the purposes of this study, an ‘ACW’ was defined as any employed staff who have any form of direct or indirect involvement with the delivery of care, support and administrative services to residents. Of all the employed staff (668) that were invited to participate, 146 staff agreed, were recruited and completed a questionnaire which collected information on the vaccination status of the staff and other background medical and demographic information during the months of March to July 2018. Teams of researchers were invited by the managers to present the study during staff meetings and handovers to recruit participants who would provide consent and fill in the questionnaire during that time. Depending on the preference of the manager, information regarding the study was presented to the staff by a member of the research team, the manager, or a combination of both. A separate survey was completed by respective managers of each facility which collected baseline data regarding employment and institutional policies on influenza vaccination programs for staff.
2.3. Covariates We included age [27], sex [28], ethnicity [29], birth country [30], marital status [31], household arrangement [32], education [32], employment history [32], smoking and alcohol history [33,34], medical history [35] and previous vaccination history [36] as covariates in our analysis due to potential confounding effects identified in the literature. Age was categorized as < 40 years or 40 years, as the median age was close to 40, and sex (male or female) was determined by medical record review. Ethnicity was categorized as Caucasian and ‘‘other” while country of birth was categorized as Australia and ‘‘other”. Marital status was considered as three categories: never married, married and ‘‘other”. Household arrangement was explored by whether children or older adults were in the household. These two variables were dichotomized (present or not) to create a consistent approximate representation of household arrangement across all the participants. Highest level of education was pooled into two categories: ‘university degree’, which includes undergraduate and post graduate qualifications, and ‘other’ which indicates a level of education below university education (e.g. school certificate, higher school certificate, trade certificate or diploma). ACWs were further categorised into ‘daily carer’ and ‘other’ depending on their frequency and quality of interaction with residents. ‘Daily carers’ included age carers, nurse’ aides and specialised dementia carers, all of whom are directly involved in the day-to-day care of the resident. ‘Others’ indicated ACWs who provide any form of support or service to the residents on less frequent basis, such as the registered nurse, pastoral care, manager, workplace trainer, caterer, and administrative staff. Participating facilities were also categorised based on the type of vaccination program offered to staff. Site B and Site D offered free onsite vaccine services for staff while the facilities at Site A and Site C only offered reimbursements for vaccines acquired from private general practitioners or local pharmacies. Smoking status was defined as a categorical variable where current and those who previously smoked (ex-smokers) were compared against those who were non-smokers. Comorbidities and previous year vaccination status were binary variables. We conducted a logistic regression analysis of the associations between the variables in Table 3 and influenza vaccination status in 2018. These variables were examined against the influenza vaccination status in 2018 to determine statistical significance in bivariate analyses. Those variables that were statistically significant were included in the multivariate model. 2.4. Data analysis All data were collated in a secured, private drive and then manually entered into Microsoft Access 2013 and analysed in IBM SPSS Statistics 25. All cases with missing data on the 2018 influenza vaccination outcome were excluded from analysis. Overall influenza vaccination rate was calculated and descriptive analysis was
Table 1 Participation rate by facilities with respondents.
2.2. Outcome measures Vaccine uptake was defined as the percentage of ACWs who received an influenza vaccine during the months of March to July 2018 (recruitment period). Participants who were not sure if they were going to be vaccinated were classified as ‘‘undecided” and those who were recruited before the annual influenza vaccine were announced and hence had not received the current influenza vaccine were followed up at the end of the recruitment period and the final vaccination status was recorded.
Facility
No. Employed
No. Consented
Participation rate
Site A Facility Facility Facility Site B Site C Facility Facility Site D Total
296 123 38 135 115 187 108 79 70 668
81 43 7 31 32 15 14 1 18 146
27% 35% 18% 23% 28% 8% 13% 1% 26% 22%
A1 A2 A3
C1 C2
Please cite this article as: E. Lai, H. Y. Tan, M. Kunasekaran et al., Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia, Vaccine, https://doi.org/10.1016/j.vaccine.2020.01.004
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conducted for each variable against the rates of 2018 influenza vaccination. Table 1 displays the rates of vaccination by site. Total completed responses were used instead of total number of participants to calculate proportions for each variable due to incomplete questionnaires (refer to Table 2 for denominators). Univariate analysis included chi square tests, or binary logistic regression with p values < 0.05 considered statistically significant. Odds ratios (OR) and 95% confidence interval (CI) were calculated. Multiple logistic regression was used to examine the predictive indicators of influenza vaccination uptake among ACWs. 3. Ethics approval This research was reviewed and approved by The University of New South Wales Human Research Ethics Committee (HREC) under the project number HC17996. Approval was also sought and obtained from the ethics board of the aged care provider under
Table 2 Demographic characteristics (total n = 135). Variable Age, years Mean (S.D.) <40 40 Gender Female Male Ethnicity Caucasian Other Birth Country Australia Other Marital status Never married Married Other* Child(ren) in household Present None Older individual(s) in household Present None Education University degree Other Occupation Daily carer Other Employment status Full time Part time Casual work Workplace vaccination policy Free onsite vaccine service Private GP with reimbursement Smoking status Current/ex-smoker Non-smoker Comorbiditiesy Present None Previous year vaccination Vaccinated Not vaccinated Influenza vaccination 2018 Vaccinated Not vaccinated
No.
Percent
75/134 59/134
37.9 (±13.9) 56.0 44.0
114/135 21/135
84.4 15.6
56/130 74/130
43.1 56.9
59/134 75/134
44.0 56.0
42/134 74/134 18/134
31.3 52.2 13.3
47/134 87/134
35.1 64.9
13/124 111/124
10.5 89.5
66/135 69/135
48.9 51.1
111/131 20/131
84.7 15.3
35/134 79/134 20/134
26.1 59.0 14.9
48/135 87/135
35.6 64.5
41/134 93/134
30.6 69.4
36/134 98/134
26.9 73.1
43/127 84/127
33.9 66.1
65/135 70/135
48.1 51.9
*Other includes: divorced (n = 14), widowed (n = 1), other (unspecified) (n = 3). Comorbidities include: asthma, cardiovascular disease, respiratory disease, diabetes, and ‘others’. Denominator varied according to the total number of responses for that variable.
y
3
the project code R153. Confidentiality of the participants and their data were ensured by the removal of all identifications prior to analysis.
4. Results The questionnaire was completed by 146 ACWs across the four sites. Among the 8 facilities which had agreed to participate, there were no participants from Facility A4, which was subsequently excluded from data analysis to avoid the skewing of results. Among the 4 sites (7 facilities), response rate varied with an overall participation rate of 22% (range 8–28%) (Table 1). The information regarding the characteristics of those that did not participate in the study was not available and the results obtained could be overestimating the vaccine uptake. As those who are not likely to participate in studies are also not likely to be vaccinated due to having similar barriers as reflected in the literature [37–39]. We can assume that the actual uptake could be lower if more respondents from facilities with no free access to the vaccine participated. Baseline data provided from the managers showed that the mean number of staff employed per site was 175 (range 70– 327). The age of the participants ranged from 18 to 69 with a male to female ratio of 1:5. Participants reported birth countries from all continents: Oceania (n = 67), Asia (n = 49), Africa (n = 8), Europe (n = 6), South America (n = 3) and North America (n = 1). Only 44% of respondents were born in Australia and 43% identified as Caucasian. There was found to be a large concentration of migrant workers from Asian countries, especially Nepal (19%) and Philippines (9%). The majority were married (52%) and most were residing in households with no children (65%) or older individuals over the age of 65 (90%). Almost half the respondents held university qualifications such as a bachelor or post-graduate degree (49%). The majority of respondents provided daily care for residents (85%) and the range of employment type undertaken were: aged carers (85%), nursing (7%), managerial, training and administrative staff (6%), and others (2%). The employment characteristics of participating staff were examined and compared to the baseline data collected from respective managers. There were found to be an overrepresentation of aged carers in our study and fewer registered nurses. The majority of the respondents were employed on a part time basis (59%) compared to full time (26%) and casual work (15%). Most respondents were non-smokers (69%) and a large majority were without chronic illnesses (73%). This could have introduced a bias as it may not have been representative of the ACW in the facilities as those who were health conscious were more likely to also be willing to participate in the study [39]. Results from the questionnaires also demonstrated an increased in influenza uptake from 2017 (34%) to 2018 (48%) (Table 2). In univariate analysis, five predictors were significantly associated with influenza vaccine uptake in 2018: previous year’s vaccination, workplace policy on influenza vaccination among staff, presence of comorbidities, employment status and marital status. These variables remained significant in multivariate analysis, except marital status (Table 3). Previous influenza vaccine uptake had the strongest association, and respondents who vaccinated in 2017 were significantly more likely than those who did not, to vaccinate in 2018 (OR 10.49, 95% confidence interval [CI] 3.33–33.10). The odds of vaccination amongst staff in facilities which offered free onsite vaccine services were 8 times greater than the odds of vaccination amongst staff in facilities which only offered reimbursements for the cost of vaccines acquired from private physicians or from local pharmacies (OR 7.87, 95% CI 2.47–25.10). Respondents with underlying chronic
Please cite this article as: E. Lai, H. Y. Tan, M. Kunasekaran et al., Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia, Vaccine, https://doi.org/10.1016/j.vaccine.2020.01.004
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Table 3 Predictors of influenza vaccine uptake. Variable Age, years <40 40 Gender Male Female Ethnicity Other Caucasian Birth country Other Australia Marital status Never married Married Other* Child(ren) in household None Present Older individual(s) in household None Present Education Other University degree Occupation Other Daily carer Employment status Full time Part time Casual work Workplace vaccination policy Private GP with reimbursement Free onsite vaccine service Smoking status Non-smoker Current/ex-smoker Comorbiditiesy No Yes Previous year vaccination No Yes
Proportion vaccinated
Rate (%)
Univariate analysis (OR, 95% CI)
Multivariate analysis (OR, 95% CI)
32/75 32/59
42.7 54.2
Ref. 1.59 (0.80–3.17)
Ref. 0.64 (0.20–2.02)
11/21 54/114
52.4 47.4
Ref. 0.82 (0.32–2.08)
Ref. 0.39 (0.11–1.36)
31/74 31/56
41.9 55.4
Ref. 1.72 (0.85–3.47)
Ref. 2.79 (0.83–9.39)
36/75 28/59
48.0 47.5
15/42 35/74 14/18
35.7 47.3 77.8
Ref. 0.98 (0.49–1.94) Ref. 1.61 (0.74–3.52) 6.30 (1.76–22.61)
Ref. 1.67 (0.54–5.39) 2.75 (0.43–1.54)
43/87 22/47
49.4 46.8
Ref. 0.90 (0.44–1.83)
50/111 8/13
45.0 61.5
Ref. 1.95 (0.60–6.34)
35/69 30/66
50.7 45.5
Ref. 0.81 (0.41–1.59)
Ref. 1.28 (0.42–3.94)
10/20 52/111
50.0 46.8
Ref. 0.88 (0.34–2.29)
Ref. 2.82 (0.65–12.27)
21/35 38/79 5/20
60.0 48.1 25.0
Ref. 0.62 (0.28–1.39) 0.22 (0.07–0.75)
Ref. 0.30 (0.09–0.99) 0.14 (0.02–0.77)
32/87 33/48
36.8 68.8
Ref. 3.78 (1.79–8.00)
Ref. 7.87 (2.47–25.10)
44/93 20/41
47.3 48.8
Ref. 1.06 (0.51–2.21)
Ref. 0.37 (0.11–1.23)
42/98 23/36
42.9 63.9
Ref. 2.36 (1.07–5.19)
Ref. 4.04 (1.23–13.32)
31/84 32/43
36.9 74.4
Ref. 4.97 (2.20–11.25)
Ref. 10.49 (3.33–33.10)
*Other includes: divorced (n = 14), widowed (n = 1), other (unspecified) (n = 3). y Comorbidities include: asthma, cardiovascular disease, respiratory disease, diabetes, and ‘others’. Denominator varied according to the total number of responses for that variable. Bolded text indicates statistically significant (p values < 0.05).
illness had greater odds of vaccination in 2018 (OR 4.04, 95% CI 1.23–13.32). Compared to full time workers, part timer workers (OR 0.30, 95% CI 0.09–0.99) and casual workers (OR 0.14, 95% CI 0.02–0.77) were less likely to be vaccinated (Table 3). 5. Discussion Our study found a 20% higher uptake than recorded in a 2003 cross-sectional survey conducted in the Australian Capital Territory (28%), although it falls far below the 95% coverage recommended by Communicable Diseases Network of Australia (CDNA) [25–26]. This study population comprised a large proportion of migrants (56%). The strongest determinants of vaccine uptake among ACWs were previous year vaccination history (OR 10.49, 95% CI 3.33–33.10), workplace immunisation programs for employees (OR 7.87, 95% CI 2.47–25.10), casual work as employment status (OR 0.14, 95% CI 0.02 – 0.77), and presence of comorbidities (OR 4.04, 95% CI 1.23–13.32). Our results are consistent with international studies which average at a 50% vaccination rate [23,40–45]. However, there were large discrepancies in uptake rate between facilities [40]. Perceived
barriers to the influenza vaccine include accessibility and cost, beliefs about efficacy and negative effects, such as scepticism towards staff influenza vaccination and workplace attitudes towards adherence guidelines and recommendations [46]. As such, facility-level differences such as management policies, staff education and workplace immunization programs would also contribute to the vaccination uptake rate [41,42,47–49]. Examples of influenza immunisation programs include: provision of vaccine, tracking vaccine uptake, reminder systems, education, and the implementation of an opt-out policy where a written declination form is required for non-immunisation which have been shown to be effective in raising ACW vaccine uptake [41]. Consistent with the literature, our findings suggest that workplace provision of influenza vaccination plays an important part in the decision to immunise, with higher vaccination rates in facilities providing onsite vaccination. The study population included a large proportion of migrant workers staying in Australia, anecdotally holding working visas rather than permanent resident visas, although we did not collect data on this. Anecdotally, ACWs reported not having Medicare access and having to meet out of pocket costs for vaccination.
Please cite this article as: E. Lai, H. Y. Tan, M. Kunasekaran et al., Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia, Vaccine, https://doi.org/10.1016/j.vaccine.2020.01.004
E. Lai et al. / Vaccine xxx (xxxx) xxx
As Medicare is offered only to Australian and New Zealand citizens and permanent visa holders, migrants on working visas are not eligible to receive government subsidised healthcare privileges which would cover the consultation fees of a physician [50]. In such cases, an ACW on a working visa seeking vaccination from their physician would be required to pay out of pocket the cost of both the consultation and the vaccine. The out of pocket cost of vaccination may be a significant disincentive for such ACWs, even if reimbursement is offered by the employer. Therefore, free, onsite vaccine services are able to overcome inconvenience, cost and accessibility for all ACWs and reinforce the employer’s support for immunisation [26,49,51,52]. In the absence of such services, ethnic disparities among HCWs have been shown to be reduced through education [29]. Living with underlying chronic illnesses has also been shown to be a positive predictor of vaccination status likely due to increased health awareness. A patient’s decision making is significantly influenced by their physicians, therefore increased interaction with their physicians may lead to increased opportunities for health education and promotion of influenza vaccination [53]. The decision to vaccinate is affected by several factors including trust or mistrust in the efficacy of modern medicine, side-effects from previous vaccination, perceived risk-benefit ratio associated with influenza and concerns that the vaccine could exacerbate underlying conditions such as asthma [54,55]. In general, influenza vaccination is an effective public health intervention in preventing seasonal influenza infection, hospitalization and mortality. In a systematic review, Restivo and colleagues concluded that influenza vaccination of HCWs is the most effective public health strategies for preventing nosocomial influenza transmission and reducing ILI mortality among elderly and high-risk patients, as well as for minimizing absenteeism during annual epidemics [56]. Hence, mandatory vaccination could be a potential method of targeting low vaccine uptake in health care settings in Australia. In Australia, there have been initiatives to protect vulnerable patient groups via high vaccine uptake among healthcare workers evident in the new policies regarding mandatory influenza vaccination in hospital wards with immunocompromised patients such as the ante-, peri-, post-natal wards, oncology and transplant wards, and all intensive care units [57]. Aged care, however, is not a health care setting, and nor are residents ‘‘patients.” Although people over the age of 65 are recognised to be a high-risk population, it is not currently compulsory for ACWs to receive the seasonal influenza vaccine. Since April 2018, it has been compulsory for all Australian ACFs to recommend influenza immunization to their staff and increase awareness related to it [58]. According to baseline information of each facility provided by the managers, all ACWs, regardless of facility and location, were ‘encouraged’, via meetings and posters in common areas, to get the annual influenza vaccination. However, due to the sensitive nature of the topic of vaccination, there could have been some hesitancy to explicitly advocate for immunisation. This highlights the need for education and advocacy related to influenza vaccination. Positive determinants of vaccine uptake include: the perception of increased risk of infection as an ACW and knowledge of the effectiveness of vaccines in protecting themselves, the residents and their family; and the awareness of employee recommendations and programs regarding influenza vaccination for ACW [26,51,52,59]. If education regarding influenza vaccination is not provided through workplace training or advocacy, many ACWs will have misperceptions about influenza vaccine. Another occupational characteristic which play a role in vaccine uptake among ACWs is employment status. Compared to casual and part-time workers, full-time ACWs typically have the longest cumulative work hours per week (i.e. 35–40+ hours) and greater permanency in their job [60]. These factors may heighten the sense
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of duty of care and thereby compel full-time ACWs to vaccinate in order to extend protection to the residents under their care. Alternatively, increased contact with residents may increase the perception of the risk of infection, motivating ACWs to vaccinate for the protection of themselves and their contacts. The delivery of vaccination services is complicated by variations in staff working hours and with the difficulty of capturing shift-workers who are not able to come in at other times outside their shifts as they could be working in other sites [61]. Given the largely casual and parttime nature of the Australian ACFs workforce, vaccination policies which target staff are not as well-researched as those working in hospital. More research is needed to understand this difference and improve implementation of workplace implementation policies. Thomas and colleagues concluded in their review of four cluster randomized control trials and one cohort study of influenza vaccine in HCW working in ACFs, that there was no conclusive evidence of benefit of healthcare worker vaccination programmes to people over the age of 60 who live in ACFs [62]. Therefore, the emphasis on influenza vaccination and addressing organizational barriers to vaccine uptake in ACFs, does not negate the need for the implementation of other non-vaccination associated workplace strategies regarding the management of influenza. Education has a role in not only improving influenza vaccine uptake but also in improving influenza control and management overall [49]. The strengths of this study is in our definition of ACW which encompasses all groups of workers within an ACF, as opposed to only focusing on care staff. By doing so, we acknowledge that any person interacting within both the ACF and the wider community have the potential to act as a vector for the influenza virus. A caveat of this study is the low response rate, despite multiple channels used to make staff aware of the study. Shift work and lack of time was cited as a factor. Although the study had been designed in collaboration with representatives of the aged care provider, there was little incentive for the staff to participate and volunteer their time. Low participation rate of 22% not only weakens the power of this study but increases the risk of bias. There could have been preferential participation by those with positive opinions regarding immunisation which may result in an overestimation of vaccine uptake. Recall bias might be present as the completion of the demographic, occupational and medical details were selfreported. Although this was mitigated by consented access to the participant’s general practitioner, with the introduction of a new pathway to influenza vaccination through local pharmacies and a more systematic collection of information through the Australian Immunization Register, gaps in keeping proper records will be further reduced. Conclusions drawn from this dataset have limited generalizability due to low response rates and the small number of ACFs involved, although attempts have been made to address bias. Despite the challenges of conducting studies in the ACF setting and limitations of the findings, staff vaccination rates are well below recommended levels and should be addressed in future policy.
6. Conclusion The Australian aged care workforce is a unique occupational group, with over half being migrants and many being ineligible for government subsidised healthcare. Vaccine uptake among ACWs remains suboptimal, but provision of workplace vaccination can overcome this barrier. We recommend more research into ACFs and the ACW workforce, looking specifically at their needs and the barriers to vaccination. By addressing issues of misconcep-
Please cite this article as: E. Lai, H. Y. Tan, M. Kunasekaran et al., Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia, Vaccine, https://doi.org/10.1016/j.vaccine.2020.01.004
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E. Lai et al. / Vaccine xxx (xxxx) xxx
tions, unawareness, cost and accessibility, higher vaccine uptake could be achieved. Ethical statement This manuscript has not been published previously in print or electronic format and is not under consideration by another publication or electronic medium. The Corresponding Author has the right to grant on behalf of all authors and does grant on behalf of all authors, an exclusive licence on a worldwide basis to the BMJ Publishing Group Ltd to permit this article (if accepted) to be published in BMJ editions and any other BMJPGL products and sublicenses such use and exploit all subsidiary rights, as set out in our licence. CRediT authorship contribution statement Elisa Lai: Writing - original draft, Data collection, Formal analysis, Investigation. Hao Yi Tan: Data collection, Investigation. Mohana Kunasekaran: Data collection, Writing - review & editing, Investigation, Project administration. Abrar Ahmad Chughtai: Data collection, Supervision, Formal analysis. Mallory Trent: Data collection, Investigation, Project administration, Data curation. Christopher Poulos: Conceptualization and site supervision. C. Raina MacIntyre: Conceived and designed the study, supervised study analysis, contributed to data cio writing. Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: This work was supported by a grant from the NHMRC Centre of Research Excellence in Integrated Systems for Epidemic Response (ISER) under the grant ID 1107393. Professor C Raina MacIntyre is supported by a NHMRC Principal Research Fellowship of grant ID 1137582. Acknowledgements The authors thank the staff at the ACFs for their assistance with the study. Their help has been greatly valued. References [1] Australian government department of health. 2017 Influenza season in Australia: A summary from the national influenza surveillance committee. Canberra: Department of Health; 2017 22 November 2017. [2] Newall AT, Viboud C, Wood JG. Influenza-attributable mortality in Australians aged more than 50 years: a comparison of different modelling approaches. Epidemiol Infect 2010;138(6):836–42. [3] Newall AT, Wood JG, MacIntyre CR. Influenza-related hospitalisation and death in Australians aged 50 years and older. Vaccine 2008;26(17):2135–41. [4] Castilla J, Cia F, Zubicoa J, Reina G, Martinez-Artola V, Ezpeleta C. Influenza outbreaks in nursing homes with high vaccination coverage in Navarre, Spain, 2011/12. Euro Surveillance: Bulletin Europeen sur les maladies transmissibles = European Communicable Disease Bulletin 2012;17(14). [5] Australian Government Department of Health. 2017 Influenza season in Australia a summary from the National Influenza Surveillance Committee Canberra2017 [updated 22 November 2017. Available from: https://www1. health.gov.au/internet/main/publishing.nsf/Content/ 097F15A91C05FBE7CA2581E20017F09E/$File/2017-season-summary22112017.pdf. [6] Goodwin K, Viboud C, Simonsen L. Antibody response to influenza vaccination in the elderly: A quantitative review. Vaccine 2006;24(8):1159–69. [7] Leekha S, Zitterkopf NL, Espy MJ, Smith TF, Thompson RL, Sampathkumar P. Duration of influenza a virus shedding in hospitalized patients and implications for infection control. Infect Control Hosp Epidemiol 2007;28 (9):1071–6. [8] Tennant E, Fletcher S, Kakar S, Najjar Z, Lord H, Clark P, et al. Factors associated with adverse outcomes during influenza outbreaks in aged care facilities. Aust NZ J Public Health 2019.
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Please cite this article as: E. Lai, H. Y. Tan, M. Kunasekaran et al., Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia, Vaccine, https://doi.org/10.1016/j.vaccine.2020.01.004