Seasonal influenza and 2009 H1N1 influenza vaccination coverage among pregnant women--10 states, 2009-10 influenza season

Because pregnant women are at increased risk for severe disease associated with influenza infection, the American College of Obstetricians and Gynecologists and the Advisory Committee on Immunization Practices have recommended seasonal influenza vaccination for women while pregnant, regardless of trimester. In 2009, a novel strain of influenza A (H1N1) virus was identified, and pregnant women also were found to be at greater risk for influenza-related complications from this new virus. As a result, during the 2009--10 influenza season, two separate influenza vaccines were recommended to pregnant women: inactivated trivalent 2009--10 seasonal vaccine and influenza A (H1N1) 2009 monovalent vaccine. To estimate influenza vaccination coverage among pregnant women during the 2009--10 influenza season, CDC analyzed data from 10 states from the Pregnancy Risk Assessment Monitoring System (PRAMS). This report summarizes the results of that analysis, which determined that vaccination coverage for pregnant women among the 10 states combined was 50.7% for seasonal influenza and 46.6% for 2009 H1N1. In addition, women to whom vaccination was offered or recommended by their health-care provider were significantly more likely to report being vaccinated against seasonal influenza (relative risk [RR] = 3.3) and 2009 H1N1 (RR = 10.1). These results indicate substantially higher influenza vaccination coverage among pregnant women than has been reported for previous influenza seasons and support previous findings that receipt of influenza vaccination can be influenced greatly by health-care providers offering or recommending influenza vaccination.     

Seasonal influenza vaccine coverage among pregnant women: pregnancy risk assessment monitoring system

Since 2004, the American College of Obstetricians and Gynecologists (ACOG) and the Advisory Committee on Immunization Practices (ACIP) have recommended that pregnant women receive the seasonal influenza vaccine, regardless of pregnancy trimester, because of their increased risk for severe complications from influenza. However, the uptake of the influenza vaccine by pregnant women has been low. During the 2009-2010 influenza season, pregnant women were identified as a priority population to receive the influenza A (H1N1) 2009 (2009 H1N1) monovalent vaccine in addition to the seasonal influenza vaccine. In this issue, we highlight information from the 10 states that collected data using the survey administered by the Pregnancy Risk Assessment and Monitoring System (PRAMS) about seasonal vaccine coverage among women with recent live births and reasons for those who chose not to get vaccinated. The combined estimates from PRAMS of influenza vaccination coverage for the 2009-2010 season, which included data from October 2009 to March 2010, from 10 states were 50.7% for seasonal and 46.6% for 2009 H1N1 vaccine among women with recent live births. Among women who did not get vaccinated, reasons varied from worries about the safety of the vaccines for self and baby to not normally getting the vaccination. Further evaluation is needed on ways to increase influenza vaccination among pregnant women, effectively communicate the risk of influenza illness during pregnancy, and address women's concerns about influenza vaccination safety during pregnancy.     

Influenza vaccination coverage among pregnant women - 29 States and New York City, 2009-10 season

Because influenza can be especially severe during pregnancy, the American College of Obstetricians and Gynecologists (ACOG) and the Advisory Committee on Immunization Practices (ACIP) recommend influenza vaccination for women who will be pregnant during the influenza season, regardless of trimester. During the 2009-10 influenza season, pregnant women were at increased risk for severe disease and mortality from influenza A (H1N1)pdm09 (pH1N1) pandemic virus infection. Anticipating this risk, both the inactivated trivalent seasonal and monovalent pH1N1 vaccinations were recommended for pregnant women. To estimate state-specific seasonal and pH1N1 influenza vaccination coverage among pregnant women, CDC analyzed data from the Pregnancy Risk Assessment Monitoring System (PRAMS). This report provides estimates from 29 states and New York City (NYC) for women who had live births during September 2009-May 2010. Median state coverage was 47.1% for seasonal and 40.4% for pH1N1 influenza vaccination. Overall, women who reported that a health-care provider offered them influenza vaccination or told them to get it during their pregnancy were more likely to be vaccinated than those without an offer or recommendation (prevalence ratio [PR] = 5.2 for seasonal, and PR = 14.4 for pH1N1). Substantial variation across areas was observed for prevalence of a provider offer or recommendation during pregnancy and for influenza vaccination. These findings highlight the need for state-specific strategies that optimize provider involvement to increase influenza vaccination of pregnant women.     

Cost-effectiveness of seasonal inactivated influenza vaccination among pregnant women

ObjectiveTo evaluate the cost-effectiveness of seasonal inactivated influenza vaccination among pregnant women using data from three recent influenza seasons in the United States.Design, setting, and participantsWe developed a decision-analytic model following a cohort of 5.2 million pregnant women and their infants aged <6 months to evaluate the cost-effectiveness of vaccinating women against seasonal influenza during pregnancy from a societal perspective. The main outcome measures were quality-adjusted life-year (QALY) gained and cost-effectiveness ratios. Data sources included surveillance data, epidemiological studies, and published vaccine cost data. Sensitivity analyses were also performed. All costs and outcomes were discounted at 3% annually.Main outcome measuresTotal costs (direct and indirect), effects (QALY gains, averted case numbers), and incremental cost-effectiveness of seasonal inactivated influenza vaccination among pregnant women (cost per QALY gained).ResultsUsing a recent benchmark of 52.2% vaccination coverage among pregnant women, we studied a hypothetical cohort of 2,753,015 vaccinated pregnant women. With an estimated vaccine effectiveness of 73% among pregnant women and 63% among infants <6 months, QALY gains for each season were 305 (2010–2011), 123 (2011–2012), and 610 (2012–2013). Compared with no vaccination, seasonal influenza vaccination during pregnancy was cost-saving when using data from the 2010–2011 and 2012–2013 influenza seasons. The cost-effectiveness ratio was greater than $100,000/QALY with the 2011–2012 influenza season data, when CDC reported a low attack rate compared to other recent seasons.ConclusionsInfluenza vaccination for pregnant women can reduce morbidity from influenza in both pregnant women and their infants aged <6 months. Seasonal influenza vaccination during pregnancy is cost-saving during moderate to severe influenza seasons.     

Maternal and infant outcomes among severely ill pregnant and postpartum women with 2009 pandemic influenza A (H1N1)--United States, April 2009-August 2010

Pregnant women with influenza are at increased risk for hospitalization and death. Since 2004, the Advisory Committee on Immunization Practices (ACIP) has recommended inactivated influenza vaccine for all women who are pregnant during influenza season, regardless of trimester. Nonetheless, after the 2004 recommendation, estimated annual influenza vaccination coverage among pregnant women was approximately 15%, before increasing to nearly 50% during the 2009 influenza A (H1N1) pandemic. Since April 2009, CDC has collaborated with state and local health departments to conduct enhanced surveillance for severe influenza among pregnant and postpartum women. To assess maternal and infant outcomes among severely ill pregnant and postpartum women with 2009 H1N1 during the 2009 H1N1 pandemic, CDC analyzed data for the period April 15, 2009 to August 10, 2010. This report summarizes the results of that analysis, which found that, among 347 severely ill pregnant women, 75 died from 2009 H1N1, and 272 were admitted to an intensive-care unit (ICU) and survived. Women who survived received antiviral treatment sooner after symptom onset than women who died. Pregnant women with severe influenza who delivered during their influenza hospitalization were more likely to deliver preterm and low birth weight infants than those in the general U.S. population; infants born after their mother's influenza hospitalization discharge were more likely to be small for gestational age. These data document the severe effects of 2009 H1N1 on pregnant women and their infants, emphasize the importance of vaccinating pregnant women against influenza, and demonstrate the value of prompt administration of antivirals to pregnant women with suspected or confirmed influenza.     

Influenza vaccination in pregnancy: practices among obstetrician-gynecologists--United States, 2003-04 influenza season

Women infected with influenza virus during pregnancy are at increased risk for serious complications and hospitalization. During 1997-2003, the Advisory Committee on Immunization Practices (ACIP) included healthy pregnant women who would be in their second or third trimester of pregnancy during the influenza season among those persons at high risk for whom influenza vaccination was indicated. Also included were women at any stage of pregnancy with certain chronic medical conditions, such as asthma, diabetes mellitus, or heart disease. ACIP emphasized that the influenza vaccine was safe for breastfeeding mothers and their infants and that household contacts of children aged <2 years also should be vaccinated. However, despite these recommendations, only 13% of pregnant women received influenza vaccination in 2003. To assess understanding of the ACIP recommendations among obstetrician-gynecologists (OB/GYNs), the American College of Obstetricians and Gynecologists (ACOG), with support from CDC, surveyed a national sample of OB/GYNs in May 2004. This report describes the results of that survey, which indicated that 52% of OB/GYNs surveyed would recommend influenza vaccination for a healthy woman in the first trimester of pregnancy, 95% would recommend the vaccine for a healthy pregnant woman beyond the first trimester, and 63% would recommend vaccination for a woman with a medical condition in the first trimester. However, of the physicians who would recommend vaccination, 36%-38% reported that influenza vaccination was not offered in their practices. Increased efforts are needed to improve vaccine availability and to educate OB/GYNs regarding the updated ACIP recommendations on the use of influenza vaccine in the first trimester for both healthy pregnant women and pregnant women at high risk.     

Influenza vaccination coverage among health-care personnel --- United States, 2010-11 influenza season

The Advisory Committee on Immunization Practices (ACIP) and the Healthcare Infection Control Practices Advisory Committee recommend that all U.S. health-care personnel (HCP) be vaccinated annually against influenza. Nonetheless, influenza vaccination coverage among HCP in the United States has increased slowly over the past decade; during the 2009-10 influenza season, 61.9% of HCP received seasonal influenza vaccination. To update data with estimates from the 2010-11 influenza season, CDC conducted an Internet-based survey of 1,931 HCP who participated in three online survey panels. This report summarizes the results of that survey, which indicated that overall influenza vaccination coverage among HCP was 63.5% during the 2010--11 influenza season, similar to coverage for the 2009-10 season. Among HCP who reported working at a facility where vaccination was required by their employer, 98.1% were vaccinated. Among HCP without such an employer requirement but who were offered vaccination onsite, greater coverage was associated with a personal reminder from the employer to get vaccinated (69.9%), vaccination availability at no cost (67.9%), and vaccination availability for >1 day (68.8%). Influenza vaccination of HCP is needed to protect patients from HCP-transmitted disease. Maximizing influenza vaccination for all HCP is an important part of any comprehensive infection-control program.     

Acceptance of vaccination during pregnancy: experience with 2009 influenza A (H1N1) in the Netherlands

Objectives

In 2009, the Dutch government advised pregnant women to get vaccinated against influenza A (H1N1). A study was set up to gain insight into vaccination coverage and reasons why pregnant women seek vaccination or not.

Methods

We invited 14,529 pregnant women to complete an internet survey on vaccination during pregnancy in general and against 2009 influenza A (H1N1). Differences in background characteristics between unvaccinated and vaccinated women were investigated. Prediction analyses were carried out to determine which survey statement had the greatest impact on vaccination status or intention to get vaccinated during pregnancy.

Results

Of the 2993 included respondents, 63% reported to be vaccinated against 2009 influenza A (H1N1). Vaccination coverage was higher among older birth cohorts, women who had been pregnant before, women with underlying medical conditions, and women who reported no defined ‘life philosophy’. Protection of the child (after birth), the government's advice and possible harmful effects of the vaccine for the unborn child had the greatest predictive value for vaccination status. With regards vaccination during future pregnancies, 39% had a positive intention to obtain vaccination and 45% were neutral. The government's advice was the strongest predictor for intention. Furthermore, women expressed concern over lack of sufficient knowledge about vaccine safety.

Conclusions

A considerable number of pregnant women in the Netherlands reported to be vaccinated against 2009 influenza A (H1N1). The challenge for the government in the future will be to provide pregnant women and health care professionals with sufficient and clear information about disease severity and the benefits and safety of vaccination.     

State-specific influenza vaccination coverage among adults--United States, 2006-07 influenza season

Adult groups included in the 2008 Advisory Committee on Immunization Practices (ACIP) recommendation for annual influenza vaccination include all persons aged >/=50 years, women who will be pregnant during the influenza season, persons aged 18-49 years with high-risk conditions, and other persons at increased risk for complications from influenza. Health-care personnel and household contacts and caregivers of persons at high risk also should receive annual influenza vaccination, as should adults who want to reduce their risk for becoming ill with influenza or for transmitting it to others. Healthy People 2010 influenza vaccination coverage targets are 90% among all persons aged >/=65 years and 60% among persons aged 18-64 years who have one or more high-risk conditions. Data from the 2006 and 2007 Behavioral Risk Factor Surveillance System (BRFSS) surveys indicate that influenza vaccination coverage among adults for the 2006-07 season increased significantly compared with the 2005-06 season, reaching 35.1% among persons aged 18-49 years with high-risk conditions, 42.0% among all persons aged 50-64 years, and 72.1% among all persons aged >/=65 years. However, vaccination coverage remained well below Healthy People 2010 targets. Increasing influenza vaccination coverage among adults in the United States will require more cooperation among health-care providers, professional organizations, vaccine manufacturers, and public health departments to raise public awareness about influenza vaccination and to ensure continued distribution and administration of available vaccine throughout the vaccination season.     

Effectiveness of influenza vaccination during pregnancy to prevent severe infection in children under 6 months of age,Spain, 2017–2019

IntroductionInfluenza vaccination is recommended to pregnant women in Spain to reduce the risk of influenza-related complications. Influenza related hospitalizations pose a significant disease burden in children every year. Although children below 6 months are too young to be vaccinated, they can receive protection against influenza through vaccination of their mothers during pregnancy. We estimated the effectiveness of maternal influenza vaccination to prevent influenza hospitalizations in infants under 6 months of age.MethodsThis is a retrospective pilot study, using data from the Severe Hospitalized Confirmed Influenza Cases (SHCIC) surveillance system in seasons 2017/18 and 2018/19 in Spain. Maternal vaccination status during pregnancy was collected for cases in children 6 months and younger hospitalized with confirmed influenza infection. Influenza vaccine effectiveness was estimated using the screening method, by comparing the proportion of children with vaccinated mothers during pregnancy (proportion of cases vaccinated, PCV), with the vaccination coverage among pregnant women in Spain (proportion of population vaccinated, PPV).ResultsFor all the study period, the PCV was 17% and the PPV was 35%. Influenza vaccination in mothers during pregnancy prevented influenza confirmed hospitalizations in infants aged 6 months and younger with a 61% (95%CI: 27–79%) effectiveness.ConclusionsIn line with evidence from other countries, influenza vaccination during pregnancy protects infants up to 6 months of age from influenza hospitalizations in Spain. These results support current recommendations of influenza vaccination in pregnant women, and more studies are needed in Spain to confirm the double protection of maternal vaccination in mothers and infants.     

Knowledge,attitudes and practices about influenza vaccination among pregnant women and healthcare providers serving pregnant women in Managua,Nicaragua

BackgroundNicaragua implemented an influenza vaccination program for pregnant women with high-risk obstetric conditions in 2007. In 2014, the recommendation of influenza vaccination expanded to include all pregnant women. Given the expansion in the recommendation of vaccination, we evaluated knowledge, attitudes and practices of pregnant women and their healthcare providers towards influenza vaccination and its recommendation.MethodsWe conducted surveys among pregnant women and their healthcare providers from June to August 2016 at two hospitals and 140 health facilities in Managua. The questions were adapted from the U.S. national CDC influenza survey and related to knowledge, attitudes and practices about influenza vaccination and barriers to vaccination. We analyzed reasons for not receiving vaccination among pregnant women as well as receipt of vaccination recommendation and offer by their healthcare providers.ResultsOf 1,303 pregnant women enrolled, 42% (5 4 5) reported receiving influenza vaccination in the 2016 season. Of those who reported not receiving vaccination, 46% indicated barriers to vaccination. Pregnant women who were vaccinated were more likely to be aware of the recommendation for vaccination and the risks of influenza illness during pregnancy and to perceive the vaccine as safe and effective, compared to unvaccinated pregnant women (p-values < 0.001). Of the 619 health workers enrolled, over 89% recalled recommending influenza vaccination to all pregnant women, regardless of obstetric risk. Of the 1,223 women who had a prenatal visit between the start date of the influenza vaccination and the time of interview, 44% recalled receiving a recommendation for influenza vaccination and 43% were offered vaccination. Vaccination rates were higher for those receiving a recommendation and offer of vaccination compared with those who received neither (95% vs 5%, p-value < 0.001).ConclusionPregnant women in Managua had positive perceptions of influenza vaccine and were receptive to receiving influenza vaccination, especially after the offer and recommendation by their healthcare providers.     

Influenza vaccination coverage among children aged 6-23 months--United States, 2005-06 influenza season

Children aged <2 years are at increased risk for influenza-related hospitalizations, and those aged <5 years have more influenza-related health-care visits than older children. In 2004, the Advisory Committee on Immunization Practices (ACIP) recommended annual influenza vaccination of children aged 6-23 months. Two doses, at least 4 weeks apart, were recommended to fully vaccinate children aged <9 years who were receiving influenza vaccination for the first time. To assess influenza vaccination coverage among children aged 6-23 months during the 2005-06 influenza season, data from the 2006 National Immunization Survey (NIS) were analyzed. This report describes the results of that analysis, which indicated that 31.9% of children in this age group received at least 1 dose of influenza vaccine and 20.6% were fully vaccinated according to ACIP recommendations; however, results varied substantially among states. The results underscore the need to continue to monitor influenza vaccination coverage among young children, develop systems to provide childhood influenza vaccination services more efficiently, and increase awareness among health-care providers and caregivers about the effectiveness of influenza vaccination among young children.     

Disparities in Influenza Vaccination Coverage Among Women with Live-Born Infants: PRAMS Surveillance During the 2009–2010 Influenza Season

Objectives

Vaccination during pregnancy significantly reduces the risk of influenza illness among pregnant women and their infants up to 6 months of age; however, many women do not get vaccinated. We examined disparities in vaccination coverage among women who delivered a live-born infant during the 2009–2010 influenza season, when two separate influenza vaccinations were recommended.

Methods

Pregnancy Risk Assessment Monitoring System (PRAMS) data from 29 states and New York City, collected during the 2009–2010 influenza season, were used to examine uptake of seasonal (unweighted n=27,153) and pandemic influenza A(H1N1)pdm09 (pH1N1) (n=27,372) vaccination by racially/ethnically diverse women who delivered a live-born infant from September 1, 2009, through May 31, 2010.

Results

PRAMS data showed variation in seasonal and pH1N1 influenza vaccination coverage among women with live-born infants by racial/ethnic group. For seasonal influenza vaccination, coverage was 50.5% for non-Hispanic white, 30.2% for non-Hispanic black, 42.1% for Hispanic, and 48.2% for non-Hispanic other women. For pH1N1, vaccination coverage was 41.4% for non-Hispanic white, 25.5% for non-Hispanic black, 41.1% for Hispanic, and 43.3% for non-Hispanic other women. Compared with non-Hispanic white women, non-Hispanic black women had lower seasonal (crude prevalence ratio [cPR] = 0.60, 95% confidence interval [CI] 0.55, 0.64) and pH1N1 (cPR=0.62, 95% CI 0.57, 0.67) vaccination coverage; these disparities diminished but remained after adjusting for provider recommendation or offer for influenza vaccination, insurance status, and demographic factors (seasonal vaccine: adjusted PR [aPR] = 0.80, 95% CI 0.74, 0.86; and pH1N1 vaccine: aPR=0.75, 95% CI 0.68, 0.82).

Conclusion

To reduce disparities in influenza vaccination uptake by pregnant women, targeted efforts toward providers and interventions focusing on pregnant and postpartum women may be needed.Pregnant women are at increased risk for complications from influenza and are more likely than the general population to be hospitalized due to respiratory illness during influenza season.^1–4 Seasonal vaccination can reduce morbidity and mortality associated with seasonal influenza.^1,2 While the influenza vaccine recommendations for pregnant women date back to the 1960s, it was in 2004 that the American College of Obstetricians and Gynecologists (ACOG) and the Advisory Committee on Immunization Practices (ACIP) recommended that women be vaccinated with the inactivated influenza vaccine any time during pregnancy.^5–7 Historically, the national estimates showed that, of the adult groups recommended to receive seasonal vaccination, pregnant women had the lowest coverage prior to the 2009–2010 influenza season.^7–9 Research has shown that there are racial/ethnic and economic disparities in vaccination coverage among adults. In general, vaccination coverage is lower among non-Hispanic black and Hispanic women than among non-Hispanic white women and women of lower socioeconomic status.^10–16 For pregnant women in particular, coverage prior to the 2009–2010 influenza season was less than 30%.^8,9Because influenza can be especially severe during pregnancy, pregnant women in particular were at increased risk of severe disease and mortality from pandemic influenza A(H1N1)pdm09 (pH1N1) virus infection.¹⁷ During the 2009–2010 influenza season, both the inactivated trivalent seasonal and monovalent pH1N1 vaccinations were recommended for pregnant women.^17,18 Pregnant women were deemed a priority group for the pH1N1 vaccine due to high morbidity and mortality associated with pH1N1 infection within this group. Monovalent pH1N1 vaccine was purchased by the federal government and made available to the public at no cost. Additionally, the monovalent vaccine was made available later than the trivalent seasonal influenza vaccine.Given the recommendation of vaccination for pregnant women and the importance of preventing morbidity and mortality from influenza, we examined disparities in vaccination uptake by pregnant women with recent live-born infants who participated in the Pregnancy Risk Assessment Monitoring System (PRAMS) survey. The rationale for examining data from the 2009–2010 influenza season was to learn about vaccination coverage of a vulnerable population (i.e., pregnant women) during the pandemic.^19,20 Research questions guiding the analysis included (1) What are the differences in vaccination coverage among racial/ethnic groups of pregnant women? and (2) Are there differences by race/ethnicity in the patterns of vaccination uptake for the two influenza vaccinations offered during the 2009–2010 influenza season?     

Survey of influenza vaccine knowledge,attitudes, and beliefs among pregnant women in the 2016–17 season

ObjectivesInfluenza vaccination coverage among pregnant women in the United States is suboptimal. We surveyed women who were pregnant during the 2016–17 influenza season to assess knowledge and attitudes regarding influenza vaccination.MethodsWe identified and sampled pregnant women to include approximately equal numbers of vaccinated and unvaccinated women from strata defined by vaccination status and trimester from four integrated health systems in the Vaccine Safety Datalink (VSD). Potential participants were contacted via mail and telephone to complete a standardized survey. Characteristics and responses of women vaccinated and unvaccinated during pregnancy were compared.ResultsThe survey was completed by 510 (48%) of 1062 contacted women; 500 were included in the analysis. Vaccine receipt while pregnant was associated with primigravida status (p = 0.02), college degree (p = 0.01), employment in health care (p < 0.01), and history of routine annual influenza vaccination (p < 0.01). Among 330 vaccinated women, the primary reasons for vaccination included protection of self and baby from influenza (n = 233, 71%), and medical professional recommendation (n = 46, 14%). Multiple reasons were given for nonvaccination, but concern about ‘negative effects’ was cited most often (n = 44, 29%). Vaccinated women were significantly more likely to believe that influenza vaccines are safe and effective, and to recognize the potential for harm from influenza infection. Nearly all women reported receiving at least one influenza vaccination recommendation from a healthcare provider.ConclusionsVaccinated pregnant women were more likely to receive routine annual influenza vaccine compared to those not vaccinated. Recommendations by obstetric providers should be supplemented with efforts to encourage women of childbearing age to receive annual vaccination.     

A multi-country investigation of influenza vaccine coverage in pregnant individuals, 2010–2016

BackgroundMany countries recommend influenza vaccination during pregnancy. Despite this recommendation, influenza vaccine among pregnant individuals remains under-utilized and uptake varies by country. Factors associated with influenza vaccine uptake during pregnancy may also vary across countries.MethodsAs members of the Pregnancy Influenza Vaccine Effectiveness Network (PREVENT), five sites from four countries (Australia, Canada, Israel, and the United States) retrospectively identified cohorts of individuals aged 18–50 years who were pregnant during pre-defined influenza seasons. Influenza vaccine coverage estimates were calculated for the 2010–11 through 2015–16 northern hemisphere and the 2012 through 2015 southern hemisphere influenza seasons, by site. Sites used electronic health records, administrative data, and immunization registries to collect information on pregnancy, health history, demographics, and vaccination status. Each season, vaccination coverage was calculated as the percentage of individuals who received influenza vaccine among the individuals in the cohort that season. Characteristics were compared between those vaccinated and unvaccinated, by site.ResultsMore than two million pregnancies were identified over the study period. Influenza vaccination coverage ranged from 5% to 58% across sites and seasons. Coverage increased consistently over the study period at three of the five sites (Western Australia, Alberta, and Israel), and was highest in all seasons at the United States study site (39–58%). Associations with vaccination varied by country and across seasons; where available, parity >0, presence of a high-risk medical condition, and urban residence were consistently associated with increased likelihood of vaccination.ConclusionsThough increasing, uptake of influenza vaccine among pregnant individuals remains lower than recommended. Coverage varied substantially by country, suggesting an ongoing need for targeted strategies to improve influenza vaccine uptake in this population.     

Flu and pertussis vaccination during pregnancy in Geneva during the COVID-19 pandemic: A multicentric,prospective, survey-based study

ObjectiveTo determine pertussis and influenza vaccination coverage during pregnancy among women delivering in all the maternities of Geneva (Switzerland), during the COVID-19 pandemic.MethodsAll women delivering in all the maternity centres of the canton of Geneva from 1st November 2020 to 30th November 2020 (beginning of the flu vaccination season) and from 8th March 2021 to 7th April 2021 (end of the flu vaccination season) had their records checked upon admission to the labour ward regarding pertussis and influenza vaccination during pregnancy. Reasons for non-vaccination were recorded. Univariate and multivariate analyses were done to identify predictors of vaccine uptake.Results951 women delivered in Geneva during the two study periods, of which 950 were included in the study. 86.2% were vaccinated against pertussis, with no significant difference between the study periods (87.5% vs 85% at the beginning and end of the flu vaccination season respectively). 49.8% were vaccinated against influenza, with no significant difference between the study periods (48.8% vs 50.7% beginning and end of the flu vaccination season respectively). The influenza vaccine was 5 times more likely not to be proposed (8.9% vs. 1.7%) and 3 times more likely to be refused (26.6% vs. 8%) than the pertussis vaccine. Main reason for refusal was a lack of maternal desire for both vaccines, but not vaccine fear. Maternal parity ≥ 1 was significantly associated with pertussis vaccine uptake at univariate analysis. Women were significantly more likely to accept the influenza vaccine if they had a university degree or if they did not deliver in a midwife-only run delivery unit in both univariate and multivariate analysis.ConclusionsIn Geneva, most gynaecologists offer pertussis immunization during antenatal care and uptake is high, but more efforts must be done to increase influenza vaccination coverage. Education level impacts maternal flu vaccination uptake, but other social disparities did not.     

Maternal pertussis and influenza immunization coverage and attitude of health care workers towards these recommendations in Flanders,Belgium

In Belgium, pertussis vaccination is recommended for all pregnant women in every pregnancy. Adults in close contact with young infants are equally advised to receive a pertussis containing booster dose. Maternal influenza vaccination is likewise recommended in Belgium in the second or third trimester of pregnancy, within the influenza season.A quantitative multicenter survey study has been performed between October 2014 and May 2015 in both postpartum women (N = 823, response rate = 89.2%) and health care workers (HCWs) (N = 261) to assess the coverage of both vaccines during pregnancy along with the coverage of the pertussis cocoon strategy, and to evaluate the knowledge and recommending attitude of HCWs towards the maternal vaccination strategies and the cocoon strategy among surveyed women and HCWs.Overall coverage of pertussis vaccination during pregnancy was 64.0%. Most women were vaccinated by their general practitioner (GP) (82.4%), and most often in the third trimester (74.0%) of pregnancy. Overall coverage of influenza vaccination during pregnancy was 45.0%. Again the GP administered most vaccines (67.6%); vaccines were equally administered in the second or third trimester of pregnancy. Educational level had a significant influence on both the pertussis and influenza vaccination coverage during pregnancy while working situation and parity had only an influence on the maternal pertussis vaccination coverage and country of birth only on the maternal influenza vaccination coverage.Overall, 78.4% of gynecologists and GPs recommends both maternal pertussis and influenza vaccination and 67.0% recommends both maternal vaccination strategies and the cocoon strategy. Within the group of the midwives, only 23.7% recommends both maternal pertussis and influenza vaccination and 10.5% recommends both maternal vaccination strategies and the cocoon strategy.High coverage is reached among pregnant women for pertussis and influenza vaccination. Several underserved populations of pregnant women regarding maternal immunization, are identified.     

Coverage of recommended vaccines during pregnancy in Flanders,Belgium. Fairly good but can we do better?

BackgroundIn Flanders, Belgium, pertussis vaccination is recommended since 2013 and available free-of-charge in every pregnancy between 24 and 32 weeks of gestation. Influenza vaccination is recommended for more than 10 years with a co-payment system in the second or third trimester of pregnancy, when pregnancy coincides with the influenza season. This study aims to estimate the coverage of pertussis and influenza vaccination during pregnancy in 2016 and to determine predictors for missing vaccination.MethodsPostpartum women were visited at home for a vaccination coverage survey using an Expanded Program on Immunization (EPI)-based two-stage cluster sampling design. Predictors for missed vaccination were identified using a multiple logistic regression model.ResultsAmong 481 participating women, 69.3% were vaccinated against pertussis and 47.2% were vaccinated against influenza. Moreover, 65.3% of pertussis vaccine recipients and 96.9% of influenza vaccine recipients were vaccinated within the recommended gestational window.Surprisingly, among women who were completely informed (i.e. on disease-associated risks, maternal vaccination costs and recommendations), still 12.4% were unvaccinated against pertussis and 23.9% against influenza.In the final models, the only common predictor of missing maternal pertussis and influenza vaccination was multiparity. Significant predictors of maternal pertussis vaccination were family income (less likely if unknown or low (< €3000) than if moderate (€3001-€4000)) and hospital of delivery (less likely if >800 annual deliveries than <800). Significant predictors of maternal influenza vaccination, though with less straight-forward associations, were maternal ethnicity and educational level, involvement of a gynaecologist in pregnancy follow-up, and characteristics of the hospital of delivery.ConclusionIn Flanders, more than two-third of pregnant women receives pertussis vaccination but less than half of them receives the influenza vaccine. Further improvement for both maternal vaccination programs can be achieved by targeting the underserved populations and diminishing vaccination hurdles.     

Pertussis and influenza immunisation coverage of pregnant women in New Zealand

BackgroundImmunisation is an important public health policy and measuring coverage is imperative to identify gaps and monitor trends. New Zealand (NZ), like many countries, does not routinely publish coverage of immunisations given during pregnancy. Therefore, this study examined pregnancy immunisation coverage of all pregnant NZ women between 2013 and 2018, and what factors affected uptake.MethodsA retrospective cohort study of pregnant women who delivered between 2013 and 2018 was undertaken using administrative datasets. Maternity and immunisation data were linked to determine coverage of pertussis and influenza vaccinations in pregnancy. Generalised estimating equations were used to estimate the odds of receiving a vaccination during pregnancy.ResultsFrom 2013 to 2018 data were available for 323,622 pregnant women, of whom 21.7% received maternal influenza immunisations and 25.7% maternal pertussis immunisations. Coverage for both vaccines increased over time, pertussis increased from 10.2% to 43.6% and influenza from 11.2% to 30.8%. The odds of being vaccinated, with either vaccine, during pregnancy increased with increasing age and decreasing deprivation. Compared to NZ European or Other women, Māori and Pacific women had lower odds of receiving a maternal pertussis (OR:0.55, 95% CI: 0.54, 0.57; OR:0.60, 95% CI: 0.58, 0.62, respectively) and influenza (OR: 0.69, 95% CI: 0.67, 0.71; OR:0.90, 95% CI: 0.87, 0.94, respectively) immunisations during pregnancy. Women were also more likely to be vaccinated against pertussis if they received antenatal care from a General Practitioner or Obstetrician compared to a Midwife. A similar pattern was seen for influenza vaccination.ConclusionGaps in maternal coverage for pertussis and influenza exist and work is needed to reduce immunisation inequities.