Impact of Patient Education on Knowledge of Influenza and Vaccine Recommendations Among Pregnant Women

Impact of Patient Education on Knowledge of Influenza and Vaccine Recommendations Among Pregnant Women

OBSTETRICS OBSTETRICS Impact of Patient Education on Knowledge of Influenza and Vaccine Recommendations Among Pregnant Women Mark H. Yudin, MD, MSc,1...

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OBSTETRICS OBSTETRICS

Impact of Patient Education on Knowledge of Influenza and Vaccine Recommendations Among Pregnant Women Mark H. Yudin, MD, MSc,1 Maryam Salripour, BSc, CIC, MPH,2 Michael D. Sgro, MD3 1

Departments of Obstetrics and Gynecology, St. Michael’s Hospital, University of Toronto, Toronto ON

2

Department of Risk Management and Quality Improvement, St. Michael’s Hospital, University of Toronto, Toronto ON

3

Department of Pediatrics, St. Michael’s Hospital, University of Toronto, Toronto ON

This work was presented at the 29th Annual Meeting of the Society for Maternal Fetal Medicine, January 30, 2009, San Diego CA.

Abstract Objective: To determine whether providing an information pamphlet in the antenatal clinic improves women’s knowledge about influenza and vaccine recommendations during pregnancy. Methods: An information pamphlet was distributed in the antenatal clinic during the fall of 2007. A cross-sectional survey was carried out in women on the postpartum floor in the fall of 2006 and again in the fall of 2007 (before and after implementation of the pamphlet) to assess women’s knowledge. Results were compared to assess knowledge transfer. Results: Knowledge improved with the use of the educational pamphlet. Most women in both years (> 90%) correctly answered that influenza is a serious infection. However, significantly more women in 2007 correctly answered that pregnant women have a higher risk of complications from influenza (34.6% in 2007 vs. 12.1% in 2006, P < 0.001), that the influenza vaccine is safe for use during pregnancy (80.2% vs. 55.2%, P < 0.001) or breastfeeding (75.3% vs. 60.3%, P = 0.001), and that the vaccine does not cause birth defects (90.1% vs. 79.3%, P = 0.04). After implementation of the information pamphlet, a significantly higher proportion of women knew the correct recommendations for influenza vaccination during pregnancy (63.2% vs. 39.7%, P < 0.001). Vaccination rates increased from 19% in 2006 to 56% in 2007. Conclusions: Providing an information pamphlet in the antenatal clinic improved pregnant women’s knowledge about influenza and vaccine safety during pregnancy and about recommendations for influenza vaccination during pregnancy. Knowledge transfer in this area may help to increase vaccination rates.

Key Words: Influenza, knowledge translation, pregnancy, vaccination Competing Interests: None declared. Received on October 15, 2009

Résumé Objectif : Déterminer si l’offre d’un dépliant d’information dans une clinique de soins prénatals améliore les connaissances des femmes au sujet des recommandations quant à la grippe et à la vaccination pendant la grossesse. Méthodes : Un dépliant d’information a été distribué dans une clinique de soins prénatals au cours de l’automne 2007. Un sondage transversal a été mené auprès des femmes du service postpartum à l’automne 2006 et, une fois de plus, à l’automne 2007 (avant et après la mise en œuvre du dépliant) en vue d’évaluer les connaissances des femmes. Les résultats ont été comparés afin d’évaluer la transmission des connaissances. Résultats : La mise en œuvre du dépliant a donné lieu à une amélioration des connaissances. La plupart des femmes des deux groupes (> 90 %) ont répondu correctement que la grippe constituait une infection grave. Cependant, en 2007, un nombre considérablement supérieur de femmes ont répondu correctement que les femmes enceintes couraient un risque accru de complications attribuables à la grippe (34,6 % en 2007, par comp. avec 12,1 % en 2006, P < 0,001), que le vaccin contre la grippe pouvait être utilisé en toute sûreté pendant la grossesse (80,2 %, par comp. avec 55,2 %, P < 0,001) ou l’allaitement (75,3 %, par comp. avec 60,3 %, P = 0,001) et que le vaccin ne causait pas d’anomalies congénitales (90,1 %, par comp. 79,3 %, P = 0,04). À la suite de la mise en œuvre du dépliant d’information, une proportion significativement accrue de femmes connaissaient les bonnes recommandations en ce qui concerne la vaccination contre la grippe pendant la grossesse (63,2 %, par comp. avec 39,7 %, P < 0,001). Les taux de vaccination sont passés de 19 %, en 2006, à 56 %, en 2007. Conclusions : Le fait d’offrir un dépliant d’information dans une clinique de soins prénatals a entraîné l’amélioration des connaissances des femmes enceintes au sujet de la grippe et de l’innocuité de la vaccination pendant la grossesse, ainsi qu’au sujet des recommandations quant à la vaccination contre la grippe pendant la grossesse. La transmission des connaissances dans ce domaine pourrait entraîner la hausse des taux de vaccination.

Accepted on November 27, 2009 J Obstet Gynaecol Can 2009;32(3):232–237

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Impact of Patient Education on Knowledge of Influenza and Vaccine Recommendations Among Pregnant Women

INTRODUCTION

nfections with the influenza virus occur in annual epidemics of respiratory illness of varying severity in people of all ages worldwide. However, the risks for complications, hospitalizations, and deaths from influenza are higher among certain groups, such as people aged 65 years or older, people of any age with underlying medical conditions, young children, and pregnant women.1 An increase in death rates associated with influenza among pregnant women was documented in the pandemics of 1916 to 1919 and 1957 to 1958 in the United States.2,3 Currently, data from the ongoing H1N1 influenza pandemic indicate that pregnant women are again at an increased risk of hospitalization and death.4,5 Excess morbidity from influenza has also been found among pregnant women in inter-pandemic seasons.6,7 Canadian data show that influenza-attributed hospitalization rates among pregnant women were 150/100 000 from 1994 to 2000, which was consistently higher than the rates among non-pregnant women.8

I

Immunization of women during pregnancy protects the mother and may benefit the fetus or infant.9,10 National bodies in Canada (the National Advisory Committee on Immunization [NACI]) and the United States (the Centers for Disease Control and Prevention [CDC] and the Advisory Committee on Immunization Practices [ACIP]) recommend the vaccine for all pregnant women because of their increased risk for influenza-related complications.1,11 There is no evidence that the vaccine is associated with adverse outcomes in pregnancy.1,11 Despite the Canadian and American guidelines for influenza vaccination during pregnancy, it is unclear how many women are offered or actually receive the vaccine while pregnant. A 1999 survey of obstetricians and gynaecologists found that only 39% administered the influenza vaccine to obstetric patients, although 86% agreed that pregnant women’s risk for influenza-related morbidity and mortality increases during the last two trimesters.12 Provider knowledge and attitudes have been shown to influence the likelihood of offering the vaccine to patients.13 Similarly, and of equal importance, there are little data on pregnant women’s knowledge of influenza, its implications in pregnancy, and the recommendations for vaccination. We have previously reported that pregnant women had poor knowledge about the safety of the influenza vaccine during pregnancy, with only 55% believing that it was safe to use in pregnancy.14 In that study, only 40% of women knew the correct recommendation for vaccination during pregnancy. Another study revealed that approximately half of pregnant women surveyed were concerned about potential side effects from

the vaccine and believed that it should be avoided during pregnancy.13 The primary objective of this study was to determine if the use of an information pamphlet in the antenatal clinic could improve patient knowledge about influenza during pregnancy, vaccine safety during pregnancy and breast feeding, and the recommendations for the use of the influenza vaccine in pregnancy. The secondary objective was to explore whether women who were willing to receive the vaccine would prefer to receive it in their physician’s office during pregnancy or while they were in the hospital on the postpartum floor. Our hypothesis was that knowledge, measured by a questionnaire, would increase with the use of the educational pamphlet. MATERIALS AND METHODS

In the fall of 2007, an educational pamphlet (Appendix A) was distributed to all patients attending the antenatal clinic at St Michael’s Hospital, which is a women’s health ambulatory care clinic in downtown Toronto serving a multi-ethnic patient population of varied socioeconomic status. The pamphlet contained information about influenza and vaccine safety during pregnancy and breastfeeding and in young children. It also contained information about recommendations for influenza vaccine in pregnant women. To assess knowledge translation, a two-page questionnaire was given to a convenience sample of 300 women on the postpartum floor at St Michael’s Hospital (Appendix B). Questions were asked about the same topics that had been discussed in the information pamphlet. The questionnaire was handed to women each morning by one of two head nurses. Women were asked to return the questionnaire to their own nurse or to drop it off at the nursing station before they left the hospital. No incentives were offered to complete the questionnaire. We have previously published results from the use of a similar questionnaire in a convenience sample of 100 women in the fall of 2006.14 In that study, no educational pamphlet was administered, as we wanted to assess baseline knowledge. The new questionnaire had two additional questions asking whether women had read the information pamphlet in the antenatal clinic, and whether they had heard about the influenza vaccine from any other sources, such as television, radio, newspapers, or the Internet. Prior to study initiation, the study authors, other physicians, and postpartum floor nurses reviewed versions of the questionnaire for face validity, and changes were incorporated for content and clarity. The final two-page version contained 18 questions, most of which were in true-false format. The questionnaire also asked whether the woman was offered the vaccine in the current or a prior pregnancy, MARCH JOGC MARS 2010 l

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Comparison of questionnaire results in year one and year two of study Correct answer 2006, n = 58 n (%)

Correct answer 2007, n = 182 n (%)

P

Flu is highly contagious.

55 (95)

169 (93)

> 0.05

Flu can sometimes be serious enough that a person needs to be admitted to the hospital.

55 (95)

176 (97)

> 0.05

Pregnant women have the same risk of complications from the flu as women who are not pregnant.

7 (12)

69 (35)

< 0.001

Question/knowledge point

The flu vaccine is safe in pregnancy.

32 (55)

146 (80)

< 0.001

The flu vaccine is safe during breastfeeding.

35 (60)

137 (75)

< 0.001

Studies have shown that the flu vaccine can cause birth defects.

12 (21)

18 (10)

0.04

Correct recommendation for influenza vaccination during pregnancy.

23 (40)

115 (63)

< 0.001

whether she was willing to receive the vaccine, and whether she would prefer to receive it in her physician’s office during pregnancy or while on the postpartum floor. For all questions, women were instructed to circle their choice. There was no sample size calculation performed for this study. All completed questionnaires were collected by one of the authors (MHY) and data were entered into a spreadsheet. The proportion of women answering each knowledge question correctly was calculated, and the proportion of women who had been offered the vaccine was determined. Statistical analyses were performed using SAS Version 9.1 (SAS Institute, Cary NC). To assess knowledge translation with the use of the information pamphlet, results from 2006 (before initiation of the pamphlet) were compared to results from 2007 (after implementation of the pamphlet). The proportion of correct answers was compared using either chi-square or Fisher exact tests, where appropriate. Ethics approval for the study was obtained from the St Michael’s Hospital Research Ethics Board. RESULTS

Educational pamphlets were distributed in the antenatal clinic from November 6 to December 27, 2007. Questionnaires were distributed on the postpartum floor from November 25 to December 31, 2007, and 182 were completed and returned (response rate 61%). In 2006, out of a convenience sample of 100 women, 58 questionnaires were completed and returned (response rate 58%). In 2007, after implementation of the information pamphlet, most women correctly answered the knowledge questions regarding the contagious and potentially serious nature of influenza, with 93% (169/182) agreeing that influenza is highly contagious and sometimes results in hospitalization. 234

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Concerning the risk of complications in young children and pregnant women, the majority of women correctly answered that young children are more likely than adults to be hospitalized with influenza 84% (153/182), but 65% (119/182) incorrectly believed that pregnant women have the same risk of complications as non-pregnant women. When asked questions about the recommendations for influenza vaccination among pregnant women in Canada, 63% (115/182) correctly answered that the vaccine was recommended for all pregnant women. Finally, knowledge regarding vaccine safety was good, with 80% (146/182) agreeing that the vaccine was safe in pregnancy, 75% (137/182) agreeing that it was safe during breastfeeding, and only 10% (18/182) believing that studies have shown the vaccine can cause birth defects. To determine knowledge sources, we asked where pregnant women had obtained information on influenza and the vaccine. Fewer than one half (68/182, 37%) stated that they had read the information pamphlet in our antenatal clinic, but 52% (95/182) had heard about the vaccine from other sources, such as television, radio, newspapers, the Internet, public health agencies, or other health care professionals. More than half of women in this study (114/182, 63%) reported that they had ever received an influenza vaccine, with 56% (103/182) having received it in the current pregnancy. This was significantly higher than the 19% (11/58) of women who reported having received the vaccine in our sample from 2006 (P < 0.001).14 Women who were willing to be vaccinated were asked whether they would prefer to receive the vaccine in their physician’s office during pregnancy or on the postpartum floor in the hospital. There was no consensus, with 45% preferring their physician’s office, 14% preferring the postpartum floor, and 41% having no preference.

Impact of Patient Education on Knowledge of Influenza and Vaccine Recommendations Among Pregnant Women

To assess the efficacy of the information pamphlet in accomplishing knowledge translation, we compared results between 2006 (before initiation of the pamphlet) and 2007 (after implementation of the pamphlet). A comparison of the results from the two years is shown in the Table. A high proportion of women in both years correctly answered that influenza is highly contagious and that hospitalization is sometimes necessary. However, significantly more women in 2007 correctly answered that pregnant women have a higher risk of complications from influenza, that the influenza vaccine is safe in pregnancy or breastfeeding, and that the vaccine does not cause birth defects. Finally, after implementing the information pamphlet in 2007, a significantly higher proportion of women knew the correct recommendations for influenza vaccination during pregnancy. DISCUSSION

In this study, after the implementation of an educational pamphlet, overall knowledge about influenza, the influenza vaccine, and implications during pregnancy increased among postpartum women, although there were still knowledge gaps. More than one half of respondents still believed that pregnant women have the same risk of complications from influenza as non-pregnant women, but almost two thirds correctly answered that the vaccine is recommended for all pregnant women. After implementation of the pamphlet, more women knew that the vaccine is safe in pregnancy and breastfeeding and does not cause birth defects, and more were aware of the recommendations for vaccination in pregnancy. Pregnant women with influenza infection are at greater risk for complications than are their non-pregnant peers, which may result from physiologic, mechanical, and hormonal alterations.15 An increase in death rates associated with influenza among pregnant women in the United States was documented in the pandemics of 1916 to 1919 and 1957 to 1958.2,3 Using hospital admission records for women admitted across Canada from 1994 to 2000 with a respiratory condition during pregnancy, Schanzer et al.8 found an admission rate of 150/100 000; the admission rate for pregnant women with a respiratory infection in the third trimester in a Tennessee Medicaid population was 250/100 000.16 These rates are equivalent to those estimated for Canadian adults aged 65 to 69 years, and 75 to 79 years, respectively.17 Currently, there is emerging evidence that pregnant women with H1N1 influenza are also at increased risk of morbidity and mortality compared to the non-pregnant population.4,5 Despite the compelling evidence that pregnant women are at increased risk for influenza-related complications and hospitalizations, 65% (119/182) of women in our study believed that pregnant women have the same risk of

complications from influenza as women who are not pregnant. However, this rate is significantly lower than the proportion who believed this prior to our implementing the information pamphlet (88%, P < 0.001). Currently, influenza vaccination for all pregnant women is recommended by national bodies in Canada (NACI) and the United States (CDC).1,11 Immunization of women during pregnancy offers protection to the woman herself by helping to prevent the infection and its associated morbidity and mortality. The infant also is protected by the passage of antibodies from the mother to the fetus during pregnancy and by the prevention of infection in the mother, which decreases the infant’s exposure risk after birth. In a randomized study of 340 mothers receiving either influenza vaccine or placebo during pregnancy, the vaccine effectiveness in preventing laboratory-confirmed influenza among infants was 63%.10 In our questionnaire, we assessed the level of knowledge possessed by pregnant women with respect to the NACI recommendations for influenza vaccination during pregnancy. Sixty-three percent (115/182) of women knew the recommended timing, and this was significantly more than the 40% (23/58) who correctly answered this question in 2006, before the use of the information pamphlet. While this increase in knowledge is encouraging, one third of respondents were still unaware of the recommendation for vaccination in pregnancy. There are many possible explanations for this, including a lack of education by health care professionals, a feeling among the general public that influenza is not a serious illness, and a failure on the part of prenatal care providers to offer the vaccine. A 2006 survey revealed that only 15% of pregnant women reported that their doctor had discussed influenza vaccination with them during pregnancy.18 Another survey of prenatal care providers identified that an important barrier to vaccination was uncertainty about who is responsible for discussing, recommending, and administering the vaccine.13 Therefore, it is incumbent upon prenatal care providers to be aware of current recommendations and to educate pregnant women about these. In addition to assessing knowledge about influenza and the vaccine recommendations during pregnancy, we also examined women’s thoughts on safety. The vaccine is considered to be safe in all stages of pregnancy and during breast feeding, and has never been associated with an obvious pattern of serious side effects, congenital malformations, or adverse pregnancy outcomes.11,19 The majority of women in our study believed the vaccine was safe in pregnancy and during breastfeeding, and only 10% thought that it had been associated with birth defects. These results were statistically significantly improved from the 2006 survey, prior to MARCH JOGC MARS 2010 l

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implementation of the information pamphlet, and better than another survey study assessing knowledge.13,14 This demonstrates that patient education can have a positive impact on knowledge. Finally, we asked women if they had been offered the vaccine in the current or a prior pregnancy, and whether they would prefer to receive it in a physician’s office during pregnancy or while on the postpartum floor. Approximately one half (56%) of women received the vaccine in the current pregnancy, which was statistically significantly higher than in the previous year (11/58, 19%, P < 0.001). This increase may have been due to increased awareness about the vaccine among both patients and providers in our clinic with the use of the information pamphlet. When asked where they would prefer to receive the vaccine, about half of women preferred their physician’s office, with a smaller proportion preferring either the postpartum floor or having no preference. This differs from the findings of Tong et al.,13 who reported that almost 80% of women preferred to receive the vaccine postpartum rather than during pregnancy. In our study, patient education may have decreased the concern about receiving the vaccine during pregnancy, resulting in more women being willing to receive the vaccine while still pregnant. This is especially important because it is preferable for women to receive the vaccine while pregnant in order to protect themselves from the complications of influenza during pregnancy. Receipt of the vaccine postpartum will clearly not protect women while pregnant, but only in the postpartum period. When comparing results from our 2007 survey, after implementation of the information pamphlet, with the 2006 results, it is clear that patient education did result in knowledge translation. Significantly more women knew the correct recommendations for vaccination in pregnancy and correctly answered questions about vaccine safety and implications of influenza in pregnant women. Further, coincident with a rise in knowledge, we demonstrated that vaccination rates increased from 19% to 56% in our patient population. Although there is still room for improvement, this is a significant gain in only one year. Vaccination rates have been shown to correlate with patient and provider attitudes and knowledge in previous studies as well.13 This study was performed prior to the current H1N1 influenza pandemic, and these results may underestimate current knowledge. Due to increased media attention, pregnant women may be more aware of current influenza vaccination recommendations than they were in previous years. Nonetheless, with the alarming rates of hospitalization, intensive care unit admission, need for ventilatory support, and death among pregnant women infected with H1N1 influenza,5 236

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interventions to increase knowledge transfer and vaccination rates are desperately needed. There are some limitations of our study. Our response rate was 61%, and we have no information on the women who did not return their questionnaires. We did not collect demographic data on participants, so we were unable to stratify answers or compare knowledge based on patient characteristics, and these results may not be applicable to all populations. We used an unvalidated questionnaire because no validated survey was available. Finally, although the increase in knowledge was likely a result of our targeted education, we cannot exclude the possibility that knowledge may have increased from one year to the next because of increased media coverage of pandemic planning or respiratory illness outbreaks. CONCLUSION

We have little information about pregnant women’s knowledge of influenza, its implications in pregnancy, and the recommendations for vaccination. Further, there is a paucity of data exploring knowledge translation in this area. The results of our study are important, and show that knowledge regarding vaccine recommendations and safety among pregnant women can be improved with patient education. In our study, this increase in knowledge translated into a significant increase in vaccination rates, which should be the ultimate goal of prenatal care programs. This is especially relevant in the setting of the current H1N1 influenza global pandemic. However, there is still room for improvement among prenatal care providers in both patient education and the actual practice of offering the vaccine to pregnant women. Patient education regarding influenza vaccination recommendations should be a standard part of prenatal care during the influenza season. Future studies should focus on more formal education programs to try to increase knowledge, and ultimately vaccination rates, among pregnant women. REFERENCES 1. Harper SA, Fukuda K, Uyeki TM, Cox NJ, Bridges CB; Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP). Prevention and control of influenza: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep 2004;53(RR-6):1–40. 2. Harris JW. Influenza occurring in pregnant women: a statistical study of thirteen hundred and fifty cases. J Am Med Assoc 1919;72(14):978–80. 3. Widelock D, Csizmas L, Klein S. Influenza, pregnancy, and fetal outcome. Public Health Rep 1963;78:1–11. 4. Centers for Disease Control and Prevention (CDC). Novel influenza A (H1N1) virus infections in three pregnant women—United States, April–May 2009. MMWR Morb Mortal Wkly Rep 2009;58:497–500. 5. Jamieson DJ, Honein MA, Rasmussen SA, Williams JL, Swerdlow DL, Biggerstaff MS, et al. H1N1 2009 influenza virus infection during pregnancy in the USA. Lancet 2009;374:451–8.

Impact of Patient Education on Knowledge of Influenza and Vaccine Recommendations Among Pregnant Women

6. Shahab SZ, Glezan WP. Influenza virus. In: Gonik B, ed. Viral diseases in pregnancy. New York: Springer-Verleg; 1994:215–23. 7. Irving WL, James DK, Stephenson T, Laing P, Jameson C, Oxford JS, et al. Influenza virus infection in the second and third trimesters of pregnancy: a clinical and seroepidemiological study. BJOG 2000;107:1282–9.

knowledge, attitudes, and behaviours towards influenza vaccination during pregnancy. J Obstet Gynaecol Can 2008;30:404–10. 14. Yudin MH, Salaripour M, Sgro MD. Pregnant women’s knowledge of influenza and the use and safety of the influenza vaccine during pregnancy. J Obstet Gynaecol Can 2009;31:120–5.

8. Schanzer DL, Langley JM, Tam TWS. Influenza-attributed hospitalization rates among pregnant women in Canada 1994–2000. J Obstet Gynaecol Can 2007;29:622–9.

15. Rasmussen SA, Jamieson DJ, Bresee JS. Pandemic influenza and pregnant women. Emerg Infect Dis 2008;14:95–100.

9. France EK, Smith-Ray R, McClure D, Hambidge S, Xu S, Yamasaki K, et al. Impact of maternal influenza vaccination during pregnancy on the incidence of acute respiratory illness visits among infants. Arch Pediatr Adolesc Med 2006;160:1277–83.

16. Neuzil K, Reed G, Mitchel E, Simonsen L, Griffin MR. Impact of influenza on acute cardiopulmonary hospitalizations in pregnant women. Am J Epidemiol 1998;148:1094–102.

10. Zaman K, Roy E, Arifeen SE, Rahman M, Raqib R, Wilson E, et al. Effectiveness of maternal influenza immunization in mothers and infants. N Engl J Med 2008;359:1555–64. 11. Public Health Agency of Canada. National Advisory Committee on Immunization (NACI) statement on influenza vaccination for the 2007–2008 season. CCDR 2007;33(ACS-7):1–38. 12. Gonik B, Jones T, Contreras D, Fasano N, Roberts C. Obstetrician-gynecologist’s role in vaccine-preventable diseases and immunization. Obstet Gynecol 2000;96:81–4. 13. Tong A, Biringer A, Ofner-Agostini M, Upshur R, McGeer A. A cross-sectional study of maternity care providers’ and women’s

17. Schanzer DL, Langley JM, Tam TWS. Modelling the impact of influenza in Canada: a baseline for pandemic planning. In: Abstracts of the Second North American Congress of Epidemiology, June 21–24, 2006; Seattle, WA. 18. Halperin BV, MacKinnon-Cameron D, McNeil S. Survey of knowledge, attitudes, and behaviour regarding influenza vaccination in pregnancy and childhood. In: Abstracts of the 2006 International Conference on Women and Infectious Diseases (ICWID), March 17–19, 2006, Atlanta, GA. Abstract #38. Available at: http://www.womenshealthconf.org/ documents/AbstractsFinal.pdf. Accessed November 5, 2009. 19. McNeil SA, Dodds L, Allen VM, Scott J, Halperin B, MacDonald N. Influenza vaccine programs and pregnancy: new Canadian evidence for immunization. J Obstet Gynaecol Can 2007;29:674–6.

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