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Dentists’ awareness toward vaccine preventable diseases
Vaccine 29 (2011) 8108–8112
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Vaccine journal homepage: www.elsevier.com/locate/vaccine
Dentists’ awareness toward vaccine preventable diseases Stefano Petti a,∗ , Giuseppe A. Messano a , Antonella Polimeni b a b
Department of Public Health and Infectious Diseases, Sanarelli Building, Sapienza University, Piazzale Aldo Moro, 5, I-00185, Rome, Italy Department of Oral and Maxillofacial Sciences, Sapienza University, Via Caserta, 6, I-00185, Rome, Italy
a r t i c l e
i n f o
Article history: Received 9 May 2011 Received in revised form 29 July 2011 Accepted 5 August 2011 Available online 19 August 2011 Keywords: Vaccine preventable diseases Immunization Dentistry Dental health care provider Infection control Awareness
a b s t r a c t Effective infection control in dentistry is unfeasible without an adequate immunization program for dental health care providers (DHCPs). Such an assumption is demonstrated for some vaccine preventable infectious diseases (VPIDs), such as Hepatitis B, Influenza and Varicella. However, excluding Hepatitis B vaccine, immunization programs for DHCPs are few and often unclear about which vaccinations are recommended, thus leading to generally low awareness and consequent low vaccination rates. This survey investigated dentists’ awareness toward VPIDs. At the moment of registration to a dental congress, a questionnaire regarding the immunization status toward VPIDs was anonymously filled in by 379 Italian dentists (86% of the contacted dentists), with at least fifteen years of activity. DHCP specific awareness was considered high if dentists reported to have controlled the serum level of anti-HBs during the last ten years and have received seasonal influenza vaccine annually. Awareness toward VPIDs was classified high if dentists reported to be immune against six or seven of the following VIPDs, Hepatitis B, Influenza, Varicella, Measles, Mumps, Rubella and Tetanus. DHCP specific awareness resulted high for 32.5% of subjects and low for 31.1%. None of the subjects reported high awareness toward VPIDs, while for 60% of them, such awareness was low (immunization status reported for none or one of the seven VPIDs). Low dentists’ awareness stresses the need for a transparent immunization program which is effective in controlling VPID transmission in the dental health care settings and focuses on those VPIDs which pose a true risk of infection for DHCPs and patients. © 2011 Elsevier Ltd. All rights reserved.
1. Introduction Immunization of dental health care workers is an effective method to control both the occupational risk for the personnel and the risk for patients. For example, epidemiological studies from all over the world, made before 1990s, reported that the risk of Hepatitis B infection among health care personnel was about four times greater than among the general population and that dental health care workers and, specifically, oral surgeons had one of the highest Hepatitis B virus (HBV) carriage rates of all health care workers. Such rates have drastically declined since the early 1990s to values lower than the general population. Several studies published before1987 reported HBV transmission from fourteen oral surgeons and nine dentists, including an oral surgeon who transmitted HBV to fifty-five patients. However, since 1987, no transmission of HBV from dentist to patient has been reported. These good results have been principally attributed to the high compliance with HBV immunization by the dental staff, and not only to the acceptance of the standard and transmission-based precautions (i.e., infection control practices that apply to all patients
∗ Corresponding author. Tel.: +39 06 4991 4667; fax: +39 06 4991 4667. E-mail address: [email protected] (S. Petti). 0264-410X/$ – see front matter © 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.vaccine.2011.08.034
regardless of their true infection status and based on the potential infectivity of blood, body fluids, droplet, contact, etc.) [1–3]. After 1987, one case of HBV transmission from patient to patient, under general anaesthesia associated with oral surgery, has been reported [4]. Thus, widespread HBV immunization by dental health care providers minimised both the occupational risk and the risk for cross-infection among patients at the same time. Another example, health care providers may acquire Influenza from patients or transmit it to patients and other staff, and positive effects of health care providers’ immunization in decreasing absenteeism rates and in reducing influenza-like illness (ILI) infection rates among staff and patients are documented [5,6]. The occupational risk for Influenza among dental health care providers is high, and non-vaccinated dental health care providers have higher prevalence of antibodies to influenza A and B viruses than the general population [7]. Influenza vaccination of dental personnel may decrease the occupational risk for the dental staff and the risk for patients. Indeed, vaccinated dentists show one half the ILI incidence than non-vaccinated dentists, as well as lower rates of ILI recurrence, absenteeism and visits to the doctor. In addition, the reported ILI episodes within patients are significantly lower [8]. Few infection control guidelines in dentistry have included an immunization program in their recommendations. In addition, excluding the vaccine against hepatitis B, which is unanimously and
S. Petti et al. / Vaccine 29 (2011) 8108–8112
strongly recommended, some of these guidelines did not mention with sufficient transparency which vaccinations are recommended and why, while other guidelines included vaccinations against diseases which do not pose a true risk for infection to the dental health care personnel and patients [3,9,10]. Recommendations for immunization of health care workers are less clouded. For example, according to the Immunization Action Coalition, supported by the Centers for Disease Control and Prevention (CDC), recommended vaccinations are: (1) Hepatitis B. The serologic test is recommended. If the health care provider is not protected (serologic test < 10 mIU/ml), vaccinate with three doses and make another serological test one-two months after dose three. (2) Influenza. One dose of Influenza vaccine annually. (3) Measles, Mumps, Rubella. If appropriate vaccination is not documented, a serological test is recommended. If the health care provider is not protected, vaccinate with two doses of MMR, four weeks apart. (4) Varicella. For health care providers who have no serologic proof of immunity (that is, prior vaccination, history of Varicella or Herpes Zoster infections based on physician diagnosis or laboratory confirmation of disease), two doses of Varicella vaccine, four weeks apart. (5) Tetanus, Diphtheria, Pertussis. Health care providers who have not or are unsure if they have previously received a dose of Tdap, should receive a one-time dose of Tdap without regard to the interval since the previous dose of Td. They should also receive Td boosters every ten years thereafter. Hepatitis A, Typhoid, Poliomyelitis, Meningitis, Tuberculosis vaccines are not routinely recommended [11,12]. The recommendations released by the Committee on Infectious Diseases of the American Academy of Pediatrics for the control of infections in pediatric ambulatory settings are very similar [13], while according to the Italian National Vaccination plan 2005–2007, Hepatitis B and Influenza vaccines are strongly recommended, as well as Measles, Mumps, Rubella and Varicella vaccinations for health care providers who are not immune [14]. However, a mere list of recommendations and guideline dissemination are not enough [15], and the increase in dentists’ knowledge does not automatically ensure an increase in awareness [16]. Indeed, awareness implies a behavioural change oriented toward the control of the condition that is sought to be prevented and not merely the knowledge of the condition, risk factors and preventive measures [17,18]. This aspect is particularly important in the field of infection control in dental health care settings since guidelines often result in an endless series of automatic processes, which may make dental health care personnel less aware of which procedures are the most effective and the most essential [19]. The present survey was aimed at investigating the level of awareness toward the vaccine preventable diseases in a sample of Italian dentists.
2. Materials and methods Dentists with at least fifteen years of activity, attending an important Italian national dental congress, were invited to participate to the survey at the moment of their registration. A self-administered anonymous questionnaire was given to those who gave their informed consent to participation. During the same day, the personnel of the congress contacted the dentists and collected the questionnaires, compiled or not, which were put into a box in order to ensure their anonymity. The items of the questionnaire, based on the recommendations of the Immunization Action Coalition and the Italian National Vaccination plan, are displayed in Table 1. Items 9 and 10 were included in the questionnaire solely to verify the overall reliability of responses. Only those questionnaires which provided negative responses to both these items were considered for further analysis.
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Table 1 Items of the self-administered questionnaires used in the present study. Only questionnaires which provided negative responses to items 9 and 10 were considered reliable and were used for the present analysis. Item
Disease
Question
Answers
1
Hepatitis B
Yes/No/I do not remember
2
Influenza
3 4 5 6 7
Measles Mumps Rubella Varicella Tetanus
8
Tuberculosis
9
Poliomyelitis
10
Scarlet fever
11
Meningitis
Have you tested your level of anti-HBs antibodies during the last ten years? Do you receive annual vaccination? Are you immune? Are you immune? Are you immune? Are you immune? Have you received a booster dose during the last ten years? Are you vaccinated? Do you test your serological level of anti-poliomyelitis antibodies every ten years? Are you vaccinated? Are you vaccinated?
Yes/No/I do not remember Yes/I do not know Yes/I do not know Yes/I do not know Yes/I do not know Yes/No/I do not remember
Yes/No/I do not remember Yes/No/I do not remember
Yes/No/I do not remember Yes/No/I do not remember
The responses to items 8 and 11 were not considered to assess awareness level, since there were no specific recommendations regarding Tuberculosis and Meningitis. The level of awareness was investigated using two methods. Namely, the basic level of awareness, toward the two most important vaccine preventable diseases which are likely to be transmitted in the dental office, that is, Hepatitis B and Influenza. Such basic awareness was arbitrarily called dental health care provider specific awareness, or DHCP-awareness. DHCP-awareness was calculated through items 1 and 2. Dentists were classified into high DHCP-awareness if they responded affirmatively to both items, medium awareness if they responded affirmatively to only one item, low awareness if they did not respond affirmatively to any of the items. The second index refers to the whole set of vaccinations recommended to health care providers, that is, Hepatitis B, Influenza, Measles, Mumps, Rubella, Varicella and Tetanus. Such awareness was arbitrarily called health care provider specific awareness, or HCP-awareness. The level of HCP-awareness was assessed giving score 1 to each affirmative response to items 1–7 and summing up the seven scores. HCP-awareness was classified into high (scores 6–7), medium-high (scores 4–5), medium-low (scores 2–3) and low (scores 0–1). The survey was made during the year 2009, the protocol was approved by the ethical committee of the Department of Public Health and Infectious Diseases of the Sapienza University of Rome. 3. Results The study showed a total of 443 dentists contacted with the prerequisites for this survey. Thirty-seven of them (8.4%) did not accept to participate, twenty-one (4.7%) did not complete the questionnaire or did not hand it in back, six of them (1.4%) provided unreliable responses to items 9 and/or 10. The final number of usable questionnaires was 379, that is, 85.6% of the contacted dentists. Mean age of the sample was 49.8 years (standard deviation, sd, 5.8). Males were 55.4% (N = 210, mean age 50.3 years, sd, 5.8),
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Table 2 Proportion of dental health care providers with at least fifteen years of activity who responded affirmatively to the various items of the questionnaire. Item
Disease
Question
Proportion (Number)
1
Hepatitis B
53.8% (204)
2
Influenza
3 4 5 6 7
Measles Mumps Rubella Varicella Tetanus
8 11
Tuberculosis Meningitis
Have you tested your level of anti-HBs antibodies during the last ten years? Do you receive annual vaccination? Are you immune? Are you immune? Are you immune? Are you immune? Have you received a booster dose during the last ten years? Are you vaccinated? Are you vaccinated?
47.5% (180) 0.8% (3) 2.6% (10) 3.4% (13) 8.7% (33) 13.2% (50)
10.8% (41) 1.6% (6)
Table 3 Level of dental health care provider-awareness (DHCP-awareness): frequency distribution of dentists according to their responses to items regarding Hepatitis B and Influenza. Hepatitis B
Influenza
DHCP-awareness Proportion (Number) Level
Yes Yes No No
Yes No Yes No
High Mediuma Mediuma Low
a
32.5% (123) 21.4% (81) 15.0% (57) 31.1% (118)
Overall medium DHCP-awareness, 36.4% (N = 138).
Table 4 Level of health care provider-awareness (HCP-awareness): frequency distribution of dentists according to the number of affirmative replies to items regarding Hepatitis B, Influenza, Measles, Mumps, Rubella, Varicella, Tetanus. Score 7 6 5 4 3 2 1 0
Proportion 0.0% (N = 0) 0.0% (N = 0) 0.8% (N = 3) 4.7% (N = 18) 8.2% (N = 31) 26.4% (N = 100) 29.8% (N = 113) 30.1% (N = 114)
HCP-awareness Level
Proportion (Number)
High
0.0% (0)
Medium-high
5.5% (21)
Medium-low
34.6% (131)
Low
59.9% (227)
females 44.6% (N = 169, mean age 49.2 years, sd, 5.7) (data not in Table). The proportion of affirmative responses was the highest for item 1 regarding Hepatitis B (53.8%), followed by item 2 regarding Influenza (47.5%) and item 7 regarding Tetanus (13.2%). 10.8% of dentists declared to be vaccinated against Tuberculosis (Table 2). Dentists were equally distributed according to the three levels of DHCP-awareness (Table 3). Namely, 32.5% showed high awareness, 36.4% medium and 31.1% low awareness. Conversely, none of the surveyed dentists showed high HCP-awareness (Table 4) and only 5.5% medium-high awareness, while almost two thirds of the sample showed low HCP-awareness. 4. Discussion The aforementioned cases of Hepatitis B and Influenza demonstrate that an effective control of infectious diseases in dental health care settings is unfeasible without an adequate immunization plan. This concept, rather than an alternative to the standard and transmission-based precautions which apply to the dental staff [20], must be conceived as an integration.
Immunization programs are present in few infection control guidelines for dental health care workers. In addition, recommendations are not always sufficiently clear. For example, the CDC refer to the national guidelines for immunization of health care providers, thus implicitly including dental health care providers. According to these guidelines, immunization against Influenza is recommended only for those health care providers who have contact with patients at high risk, or work in chronic-care facilities [3], therefore excluding, with few exceptions, dentists and oral surgeons, who have contact with patients who are certainly at risk, but generally not at high risk. According to the guidelines of the British Dental Association, all clinical staff should be vaccinated against the common illnesses, but, excluding Hepatitis B vaccine, such illnesses are not mentioned [9]. According to the guidelines for infection control released by the Irish Dental Council, dentists should be vaccinated against diseases such as Poliomyelitis and Diphtheria, which are not at high risk of transmission in dental health care settings [10]. The lack or the ambiguity of immunization programs, along with unsubstantiated concerns and misperceptions regarding vaccine efficacy and safety among dental health care providers [21], are probably at the basis of the low awareness toward vaccine preventable diseases demonstrated by the dental health care providers in this study. These data are corroborated by the results of another survey [22] made on a sample of Italian dentists (369 subjects, mean age 43.6 years, response rate 40%). 56.2% of them reported to have received complete vaccination against Hepatitis B and 33% to have received Influenza vaccination during the last year. In the present study, 53.8% and 47.5% of dentists responded affirmatively to similar items (Table 2). Very interestingly, the data reported by these authors strengthen the idea that knowledge and awareness are two distinct concepts. Indeed, the aforementioned proportions of dentists who were immune against Hepatitis B and Influenza, that is, with high awareness, were only one half the proportions of dentists who reported to know that dentists should be immunized against such diseases (95.7% and 60%, respectively), that is, with high knowledge. The various surveys investigating Hepatitis B vaccination rates in the dental staff reported various rates. Indeed, during a Hepatitis B vaccination campaign directed to dental health care workers in Spain, roughly 15% of dentists reported to be immune against Hepatitis B [23]. Immunization rates of 38.5% from Egypt [24], 40.3% from Nigeria [25], 48.2% from Japan [26], 52% from Sudan [27], 68% from Mexico [28], 73% from Jordan [29], 90% from South-Africa [30], 97% from UK [31] are reported. Thus, the picture of overall Hepatitis B vaccination rate in the dental staff is grey, with white areas merged with dark areas even from some western countries. In contrast, pictures of immunization rates for the other vaccine preventable diseases cannot be drawn, since related surveys are few or none. The only data come from dental students who are requested by law to be immunized against several diseases, not only Hepatitis B, before their admission in some universities and countries, such as US, Germany, etc. This lack of information demonstrates that even public health care providers, health policy makers, and epidemiologists could be uncertain about the vaccinations which are recommended to the dental staff and explains why dental health care providers cannot be considered fully responsible for such low awareness. Specific immunization programs directed towards dental staff are in evident contrast with programs directed towards all health care workers, which, implicitly, should include dentists. These programs are necessarily extensive [11–14], because they are directed to all health care providers, including those who work in contexts, such as HIV positive patients and preterm birth children, or intensive care, burning, cancer units, etc., where the risk for infection transmission is extremely high. Such an extensive
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immunization program could be viewed as excessive by dentists, who could, therefore, neither accept it nor put it into practice. Indeed, failure of guidelines is frequently due to the lack of consensus on recommendations among those whom guidelines are directed to [15]. In order to increase dental health care providers’ awareness toward immunization, it is necessary to design transparent programs, which must focus primarily on those vaccine preventable diseases frequently transmitted in dental health care settings which, therefore, pose a true risk for infection to personnel and patients. This program could be viewed as necessary with visible effects on the preservation of the health status of staff and patients, thus increasing awareness [19]. In order to increase the level of consensus among the dental health care providers, it is necessary to involve delegates of professional associations during the design of the program and not after its release. This method gives the impression to health care providers that recommendations are proposed and not imposed [15]. The evidence of vaccine effectiveness in the control of infectious diseases which are at high risk of transmission in dental health care settings is necessarily indirect, as field or clinical trials are unavailable. Such evidence could be used as a basis to design an immunization program specifically directed to the dental health care personnel. As already explained, indirect evidence is sufficient for Hepatitis B [1–3] and Influenza [7,8]. Another vaccine preventable disease at high risk of transmission in the dental health care setting could be Varicella. Indeed, Herpes viruses cause persistent infections in most of the population and can be found in saliva [1,2]. In addition, Varicella-Zoster virus transmitted to preschool children is responsible for enamel hypoplasia on permanent teeth with consequent high caries risk [32,33]. Dentists and clinical dental students have higher prevalence of antibodies to Epstein–Barr virus than pre-clinical dental students [34] and Herpes Simplex virus can be transmitted from patients to dental staff [35] and vice versa [36]. Such risk for Herpes virus transmission in the dental health care setting, attributable to the peculiar characteristics of dental instruments and therapy, is higher than in other health care settings, and cannot be completely controlled through the application of Standard and Transmission-Based Precautions [37]. Therefore, although specific investigations are lacking, it is likely that the risk of Varicella-Zoster virus infection, which is spread by the respiratory route [38], is also high in the dental health care setting and that personnel and patients may benefit from personnel’s immunization. All dental health care providers should be immune against these three diseases throughout their working life and, possibly, women should also be immune against Rubella. The situation is different for those providers, such as oral surgeons, or those who work in hospitals, in pediatric and oncologic units, or treat HIV-positive and other immunocompromised patients. These dental health care providers are assimilated to the other health care providers and, like them, must undergo extensive immunization programs even in absence of any evidence of an increased risk for transmission of other vaccine preventable diseases in the dental health care setting. In conclusion, the overall level of awareness toward vaccine preventable diseases of this sample of Italian dentists, with more than fifteen years of activity, is moderate to low. Such result cannot be totally ascribed to insufficient knowledge or misperceptions of providers, but also and principally to the characteristics of immunization programs, since specific programs are lacking or unclear, while health care providers’ programs are probably excessive with respect to the real risk of infection in the dental health care setting. These results suggest the need for a specific immunization plan which focuses on the vaccine preventable diseases that pose a true risk for infection in the dental health care setting.
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Acknowledgements Contributors: All Authors declare to have contributed to this study (i.e., design, execution and drafting of the paper) and have seen and approved the final version of this manuscript. Conflict of interest statement: The authors declare that they have no conflict of interest. The Authors wish to thank Dr. Lidia Socci for her fruitful support in editing the manuscript. S.P. and A.P. are members of a working group charged by the Italian Ministry of Health to develop the Italian guidelines for infection control in dentistry, a draft of such guidelines can be downloaded at “http://www.quadernidellasalute.it/download/download/ 7-gennaio-febbraio-2011-quaderno.pdf” (pp. 35–48). Guidelines and recommendations, including an adequate immunization plan, are being discussed with delegates of the Italian dental associations in order to make them acceptable by the dental health care providers.
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Contents lists available at ScienceDirect
Vaccine journal homepage: www.elsevier.com/locate/vaccine
Dentists’ awareness toward vaccine preventable diseases Stefano Petti a,∗ , Giuseppe A. Messano a , Antonella Polimeni b a b
Department of Public Health and Infectious Diseases, Sanarelli Building, Sapienza University, Piazzale Aldo Moro, 5, I-00185, Rome, Italy Department of Oral and Maxillofacial Sciences, Sapienza University, Via Caserta, 6, I-00185, Rome, Italy
a r t i c l e
i n f o
Article history: Received 9 May 2011 Received in revised form 29 July 2011 Accepted 5 August 2011 Available online 19 August 2011 Keywords: Vaccine preventable diseases Immunization Dentistry Dental health care provider Infection control Awareness
a b s t r a c t Effective infection control in dentistry is unfeasible without an adequate immunization program for dental health care providers (DHCPs). Such an assumption is demonstrated for some vaccine preventable infectious diseases (VPIDs), such as Hepatitis B, Influenza and Varicella. However, excluding Hepatitis B vaccine, immunization programs for DHCPs are few and often unclear about which vaccinations are recommended, thus leading to generally low awareness and consequent low vaccination rates. This survey investigated dentists’ awareness toward VPIDs. At the moment of registration to a dental congress, a questionnaire regarding the immunization status toward VPIDs was anonymously filled in by 379 Italian dentists (86% of the contacted dentists), with at least fifteen years of activity. DHCP specific awareness was considered high if dentists reported to have controlled the serum level of anti-HBs during the last ten years and have received seasonal influenza vaccine annually. Awareness toward VPIDs was classified high if dentists reported to be immune against six or seven of the following VIPDs, Hepatitis B, Influenza, Varicella, Measles, Mumps, Rubella and Tetanus. DHCP specific awareness resulted high for 32.5% of subjects and low for 31.1%. None of the subjects reported high awareness toward VPIDs, while for 60% of them, such awareness was low (immunization status reported for none or one of the seven VPIDs). Low dentists’ awareness stresses the need for a transparent immunization program which is effective in controlling VPID transmission in the dental health care settings and focuses on those VPIDs which pose a true risk of infection for DHCPs and patients. © 2011 Elsevier Ltd. All rights reserved.
1. Introduction Immunization of dental health care workers is an effective method to control both the occupational risk for the personnel and the risk for patients. For example, epidemiological studies from all over the world, made before 1990s, reported that the risk of Hepatitis B infection among health care personnel was about four times greater than among the general population and that dental health care workers and, specifically, oral surgeons had one of the highest Hepatitis B virus (HBV) carriage rates of all health care workers. Such rates have drastically declined since the early 1990s to values lower than the general population. Several studies published before1987 reported HBV transmission from fourteen oral surgeons and nine dentists, including an oral surgeon who transmitted HBV to fifty-five patients. However, since 1987, no transmission of HBV from dentist to patient has been reported. These good results have been principally attributed to the high compliance with HBV immunization by the dental staff, and not only to the acceptance of the standard and transmission-based precautions (i.e., infection control practices that apply to all patients
∗ Corresponding author. Tel.: +39 06 4991 4667; fax: +39 06 4991 4667. E-mail address: [email protected] (S. Petti). 0264-410X/$ – see front matter © 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.vaccine.2011.08.034
regardless of their true infection status and based on the potential infectivity of blood, body fluids, droplet, contact, etc.) [1–3]. After 1987, one case of HBV transmission from patient to patient, under general anaesthesia associated with oral surgery, has been reported [4]. Thus, widespread HBV immunization by dental health care providers minimised both the occupational risk and the risk for cross-infection among patients at the same time. Another example, health care providers may acquire Influenza from patients or transmit it to patients and other staff, and positive effects of health care providers’ immunization in decreasing absenteeism rates and in reducing influenza-like illness (ILI) infection rates among staff and patients are documented [5,6]. The occupational risk for Influenza among dental health care providers is high, and non-vaccinated dental health care providers have higher prevalence of antibodies to influenza A and B viruses than the general population [7]. Influenza vaccination of dental personnel may decrease the occupational risk for the dental staff and the risk for patients. Indeed, vaccinated dentists show one half the ILI incidence than non-vaccinated dentists, as well as lower rates of ILI recurrence, absenteeism and visits to the doctor. In addition, the reported ILI episodes within patients are significantly lower [8]. Few infection control guidelines in dentistry have included an immunization program in their recommendations. In addition, excluding the vaccine against hepatitis B, which is unanimously and
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strongly recommended, some of these guidelines did not mention with sufficient transparency which vaccinations are recommended and why, while other guidelines included vaccinations against diseases which do not pose a true risk for infection to the dental health care personnel and patients [3,9,10]. Recommendations for immunization of health care workers are less clouded. For example, according to the Immunization Action Coalition, supported by the Centers for Disease Control and Prevention (CDC), recommended vaccinations are: (1) Hepatitis B. The serologic test is recommended. If the health care provider is not protected (serologic test < 10 mIU/ml), vaccinate with three doses and make another serological test one-two months after dose three. (2) Influenza. One dose of Influenza vaccine annually. (3) Measles, Mumps, Rubella. If appropriate vaccination is not documented, a serological test is recommended. If the health care provider is not protected, vaccinate with two doses of MMR, four weeks apart. (4) Varicella. For health care providers who have no serologic proof of immunity (that is, prior vaccination, history of Varicella or Herpes Zoster infections based on physician diagnosis or laboratory confirmation of disease), two doses of Varicella vaccine, four weeks apart. (5) Tetanus, Diphtheria, Pertussis. Health care providers who have not or are unsure if they have previously received a dose of Tdap, should receive a one-time dose of Tdap without regard to the interval since the previous dose of Td. They should also receive Td boosters every ten years thereafter. Hepatitis A, Typhoid, Poliomyelitis, Meningitis, Tuberculosis vaccines are not routinely recommended [11,12]. The recommendations released by the Committee on Infectious Diseases of the American Academy of Pediatrics for the control of infections in pediatric ambulatory settings are very similar [13], while according to the Italian National Vaccination plan 2005–2007, Hepatitis B and Influenza vaccines are strongly recommended, as well as Measles, Mumps, Rubella and Varicella vaccinations for health care providers who are not immune [14]. However, a mere list of recommendations and guideline dissemination are not enough [15], and the increase in dentists’ knowledge does not automatically ensure an increase in awareness [16]. Indeed, awareness implies a behavioural change oriented toward the control of the condition that is sought to be prevented and not merely the knowledge of the condition, risk factors and preventive measures [17,18]. This aspect is particularly important in the field of infection control in dental health care settings since guidelines often result in an endless series of automatic processes, which may make dental health care personnel less aware of which procedures are the most effective and the most essential [19]. The present survey was aimed at investigating the level of awareness toward the vaccine preventable diseases in a sample of Italian dentists.
2. Materials and methods Dentists with at least fifteen years of activity, attending an important Italian national dental congress, were invited to participate to the survey at the moment of their registration. A self-administered anonymous questionnaire was given to those who gave their informed consent to participation. During the same day, the personnel of the congress contacted the dentists and collected the questionnaires, compiled or not, which were put into a box in order to ensure their anonymity. The items of the questionnaire, based on the recommendations of the Immunization Action Coalition and the Italian National Vaccination plan, are displayed in Table 1. Items 9 and 10 were included in the questionnaire solely to verify the overall reliability of responses. Only those questionnaires which provided negative responses to both these items were considered for further analysis.
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Table 1 Items of the self-administered questionnaires used in the present study. Only questionnaires which provided negative responses to items 9 and 10 were considered reliable and were used for the present analysis. Item
Disease
Question
Answers
1
Hepatitis B
Yes/No/I do not remember
2
Influenza
3 4 5 6 7
Measles Mumps Rubella Varicella Tetanus
8
Tuberculosis
9
Poliomyelitis
10
Scarlet fever
11
Meningitis
Have you tested your level of anti-HBs antibodies during the last ten years? Do you receive annual vaccination? Are you immune? Are you immune? Are you immune? Are you immune? Have you received a booster dose during the last ten years? Are you vaccinated? Do you test your serological level of anti-poliomyelitis antibodies every ten years? Are you vaccinated? Are you vaccinated?
Yes/No/I do not remember Yes/I do not know Yes/I do not know Yes/I do not know Yes/I do not know Yes/No/I do not remember
Yes/No/I do not remember Yes/No/I do not remember
Yes/No/I do not remember Yes/No/I do not remember
The responses to items 8 and 11 were not considered to assess awareness level, since there were no specific recommendations regarding Tuberculosis and Meningitis. The level of awareness was investigated using two methods. Namely, the basic level of awareness, toward the two most important vaccine preventable diseases which are likely to be transmitted in the dental office, that is, Hepatitis B and Influenza. Such basic awareness was arbitrarily called dental health care provider specific awareness, or DHCP-awareness. DHCP-awareness was calculated through items 1 and 2. Dentists were classified into high DHCP-awareness if they responded affirmatively to both items, medium awareness if they responded affirmatively to only one item, low awareness if they did not respond affirmatively to any of the items. The second index refers to the whole set of vaccinations recommended to health care providers, that is, Hepatitis B, Influenza, Measles, Mumps, Rubella, Varicella and Tetanus. Such awareness was arbitrarily called health care provider specific awareness, or HCP-awareness. The level of HCP-awareness was assessed giving score 1 to each affirmative response to items 1–7 and summing up the seven scores. HCP-awareness was classified into high (scores 6–7), medium-high (scores 4–5), medium-low (scores 2–3) and low (scores 0–1). The survey was made during the year 2009, the protocol was approved by the ethical committee of the Department of Public Health and Infectious Diseases of the Sapienza University of Rome. 3. Results The study showed a total of 443 dentists contacted with the prerequisites for this survey. Thirty-seven of them (8.4%) did not accept to participate, twenty-one (4.7%) did not complete the questionnaire or did not hand it in back, six of them (1.4%) provided unreliable responses to items 9 and/or 10. The final number of usable questionnaires was 379, that is, 85.6% of the contacted dentists. Mean age of the sample was 49.8 years (standard deviation, sd, 5.8). Males were 55.4% (N = 210, mean age 50.3 years, sd, 5.8),
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Table 2 Proportion of dental health care providers with at least fifteen years of activity who responded affirmatively to the various items of the questionnaire. Item
Disease
Question
Proportion (Number)
1
Hepatitis B
53.8% (204)
2
Influenza
3 4 5 6 7
Measles Mumps Rubella Varicella Tetanus
8 11
Tuberculosis Meningitis
Have you tested your level of anti-HBs antibodies during the last ten years? Do you receive annual vaccination? Are you immune? Are you immune? Are you immune? Are you immune? Have you received a booster dose during the last ten years? Are you vaccinated? Are you vaccinated?
47.5% (180) 0.8% (3) 2.6% (10) 3.4% (13) 8.7% (33) 13.2% (50)
10.8% (41) 1.6% (6)
Table 3 Level of dental health care provider-awareness (DHCP-awareness): frequency distribution of dentists according to their responses to items regarding Hepatitis B and Influenza. Hepatitis B
Influenza
DHCP-awareness Proportion (Number) Level
Yes Yes No No
Yes No Yes No
High Mediuma Mediuma Low
a
32.5% (123) 21.4% (81) 15.0% (57) 31.1% (118)
Overall medium DHCP-awareness, 36.4% (N = 138).
Table 4 Level of health care provider-awareness (HCP-awareness): frequency distribution of dentists according to the number of affirmative replies to items regarding Hepatitis B, Influenza, Measles, Mumps, Rubella, Varicella, Tetanus. Score 7 6 5 4 3 2 1 0
Proportion 0.0% (N = 0) 0.0% (N = 0) 0.8% (N = 3) 4.7% (N = 18) 8.2% (N = 31) 26.4% (N = 100) 29.8% (N = 113) 30.1% (N = 114)
HCP-awareness Level
Proportion (Number)
High
0.0% (0)
Medium-high
5.5% (21)
Medium-low
34.6% (131)
Low
59.9% (227)
females 44.6% (N = 169, mean age 49.2 years, sd, 5.7) (data not in Table). The proportion of affirmative responses was the highest for item 1 regarding Hepatitis B (53.8%), followed by item 2 regarding Influenza (47.5%) and item 7 regarding Tetanus (13.2%). 10.8% of dentists declared to be vaccinated against Tuberculosis (Table 2). Dentists were equally distributed according to the three levels of DHCP-awareness (Table 3). Namely, 32.5% showed high awareness, 36.4% medium and 31.1% low awareness. Conversely, none of the surveyed dentists showed high HCP-awareness (Table 4) and only 5.5% medium-high awareness, while almost two thirds of the sample showed low HCP-awareness. 4. Discussion The aforementioned cases of Hepatitis B and Influenza demonstrate that an effective control of infectious diseases in dental health care settings is unfeasible without an adequate immunization plan. This concept, rather than an alternative to the standard and transmission-based precautions which apply to the dental staff [20], must be conceived as an integration.
Immunization programs are present in few infection control guidelines for dental health care workers. In addition, recommendations are not always sufficiently clear. For example, the CDC refer to the national guidelines for immunization of health care providers, thus implicitly including dental health care providers. According to these guidelines, immunization against Influenza is recommended only for those health care providers who have contact with patients at high risk, or work in chronic-care facilities [3], therefore excluding, with few exceptions, dentists and oral surgeons, who have contact with patients who are certainly at risk, but generally not at high risk. According to the guidelines of the British Dental Association, all clinical staff should be vaccinated against the common illnesses, but, excluding Hepatitis B vaccine, such illnesses are not mentioned [9]. According to the guidelines for infection control released by the Irish Dental Council, dentists should be vaccinated against diseases such as Poliomyelitis and Diphtheria, which are not at high risk of transmission in dental health care settings [10]. The lack or the ambiguity of immunization programs, along with unsubstantiated concerns and misperceptions regarding vaccine efficacy and safety among dental health care providers [21], are probably at the basis of the low awareness toward vaccine preventable diseases demonstrated by the dental health care providers in this study. These data are corroborated by the results of another survey [22] made on a sample of Italian dentists (369 subjects, mean age 43.6 years, response rate 40%). 56.2% of them reported to have received complete vaccination against Hepatitis B and 33% to have received Influenza vaccination during the last year. In the present study, 53.8% and 47.5% of dentists responded affirmatively to similar items (Table 2). Very interestingly, the data reported by these authors strengthen the idea that knowledge and awareness are two distinct concepts. Indeed, the aforementioned proportions of dentists who were immune against Hepatitis B and Influenza, that is, with high awareness, were only one half the proportions of dentists who reported to know that dentists should be immunized against such diseases (95.7% and 60%, respectively), that is, with high knowledge. The various surveys investigating Hepatitis B vaccination rates in the dental staff reported various rates. Indeed, during a Hepatitis B vaccination campaign directed to dental health care workers in Spain, roughly 15% of dentists reported to be immune against Hepatitis B [23]. Immunization rates of 38.5% from Egypt [24], 40.3% from Nigeria [25], 48.2% from Japan [26], 52% from Sudan [27], 68% from Mexico [28], 73% from Jordan [29], 90% from South-Africa [30], 97% from UK [31] are reported. Thus, the picture of overall Hepatitis B vaccination rate in the dental staff is grey, with white areas merged with dark areas even from some western countries. In contrast, pictures of immunization rates for the other vaccine preventable diseases cannot be drawn, since related surveys are few or none. The only data come from dental students who are requested by law to be immunized against several diseases, not only Hepatitis B, before their admission in some universities and countries, such as US, Germany, etc. This lack of information demonstrates that even public health care providers, health policy makers, and epidemiologists could be uncertain about the vaccinations which are recommended to the dental staff and explains why dental health care providers cannot be considered fully responsible for such low awareness. Specific immunization programs directed towards dental staff are in evident contrast with programs directed towards all health care workers, which, implicitly, should include dentists. These programs are necessarily extensive [11–14], because they are directed to all health care providers, including those who work in contexts, such as HIV positive patients and preterm birth children, or intensive care, burning, cancer units, etc., where the risk for infection transmission is extremely high. Such an extensive
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immunization program could be viewed as excessive by dentists, who could, therefore, neither accept it nor put it into practice. Indeed, failure of guidelines is frequently due to the lack of consensus on recommendations among those whom guidelines are directed to [15]. In order to increase dental health care providers’ awareness toward immunization, it is necessary to design transparent programs, which must focus primarily on those vaccine preventable diseases frequently transmitted in dental health care settings which, therefore, pose a true risk for infection to personnel and patients. This program could be viewed as necessary with visible effects on the preservation of the health status of staff and patients, thus increasing awareness [19]. In order to increase the level of consensus among the dental health care providers, it is necessary to involve delegates of professional associations during the design of the program and not after its release. This method gives the impression to health care providers that recommendations are proposed and not imposed [15]. The evidence of vaccine effectiveness in the control of infectious diseases which are at high risk of transmission in dental health care settings is necessarily indirect, as field or clinical trials are unavailable. Such evidence could be used as a basis to design an immunization program specifically directed to the dental health care personnel. As already explained, indirect evidence is sufficient for Hepatitis B [1–3] and Influenza [7,8]. Another vaccine preventable disease at high risk of transmission in the dental health care setting could be Varicella. Indeed, Herpes viruses cause persistent infections in most of the population and can be found in saliva [1,2]. In addition, Varicella-Zoster virus transmitted to preschool children is responsible for enamel hypoplasia on permanent teeth with consequent high caries risk [32,33]. Dentists and clinical dental students have higher prevalence of antibodies to Epstein–Barr virus than pre-clinical dental students [34] and Herpes Simplex virus can be transmitted from patients to dental staff [35] and vice versa [36]. Such risk for Herpes virus transmission in the dental health care setting, attributable to the peculiar characteristics of dental instruments and therapy, is higher than in other health care settings, and cannot be completely controlled through the application of Standard and Transmission-Based Precautions [37]. Therefore, although specific investigations are lacking, it is likely that the risk of Varicella-Zoster virus infection, which is spread by the respiratory route [38], is also high in the dental health care setting and that personnel and patients may benefit from personnel’s immunization. All dental health care providers should be immune against these three diseases throughout their working life and, possibly, women should also be immune against Rubella. The situation is different for those providers, such as oral surgeons, or those who work in hospitals, in pediatric and oncologic units, or treat HIV-positive and other immunocompromised patients. These dental health care providers are assimilated to the other health care providers and, like them, must undergo extensive immunization programs even in absence of any evidence of an increased risk for transmission of other vaccine preventable diseases in the dental health care setting. In conclusion, the overall level of awareness toward vaccine preventable diseases of this sample of Italian dentists, with more than fifteen years of activity, is moderate to low. Such result cannot be totally ascribed to insufficient knowledge or misperceptions of providers, but also and principally to the characteristics of immunization programs, since specific programs are lacking or unclear, while health care providers’ programs are probably excessive with respect to the real risk of infection in the dental health care setting. These results suggest the need for a specific immunization plan which focuses on the vaccine preventable diseases that pose a true risk for infection in the dental health care setting.
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Acknowledgements Contributors: All Authors declare to have contributed to this study (i.e., design, execution and drafting of the paper) and have seen and approved the final version of this manuscript. Conflict of interest statement: The authors declare that they have no conflict of interest. The Authors wish to thank Dr. Lidia Socci for her fruitful support in editing the manuscript. S.P. and A.P. are members of a working group charged by the Italian Ministry of Health to develop the Italian guidelines for infection control in dentistry, a draft of such guidelines can be downloaded at “http://www.quadernidellasalute.it/download/download/ 7-gennaio-febbraio-2011-quaderno.pdf” (pp. 35–48). Guidelines and recommendations, including an adequate immunization plan, are being discussed with delegates of the Italian dental associations in order to make them acceptable by the dental health care providers.
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