Hepatitis B surface antigen seroprevalence among pre- and post-vaccine cohorts in Cambodia, 2017

Background: Hepatitis B virus (HBV) infection is highly endemic in most low income countries including Cambodia. This nationwide serosurvey was conducted to assess the impact of hepatitis B vaccination and to determine whether Cambodia met the WHO regional 2017 target of hepatitis B surface antigen (HBsAg) seroprevalence less than 1% in five-year-old children.Methods: A cross-sectional multi-stage cluster survey was conducted among children born during 2010–2012 and their mothers in Cambodia. HBsAg prevalence was estimated by rapid point-of-care testing, and demographic data, including vaccination history, was collected. Vaccine coverage in children and the prevalence of HBsAg among children and mothers was calculated taking into account the complex survey design. Factors associated with children’s failure to receive timely (within 24 h) vaccination were analysed by multivariate logistic analysis.Findings: A total of 2,520 children 5–7 years old and 2,028 mothers were recruited. In total, 78.4% of children received hepatitis B vaccination birth-dose (HepB-BD); of these, 58.7% were administered ≤ 24 h. Birth at home or “other” location were independent risk factors for children’s failure to receive timely HepB-BD. Overall HBsAg seroprevalence was 4.39% (95%CI: 3.53%–5.45%) among mothers and 0.56% (95%CI: 0.32%–0.98%) among children. The prevalence among children without hepatitis B vaccination was 4.62% (95%CI: 1.31%–14.97%). Among children with a HBsAg-positive mother, prevalence was 10.11% (95%CI: 5.41%–18.11%).Interpretation: Having achieved the 2017 target of less than 1% HBsAg prevalence among 5 years old children, Cambodia can now focus on eliminating mother-to-child transmission of HBV. Moreover, the high HBsAg prevalence among mothers suggests that routine screening with proper linkage to care and treatment is needed. Strengthening measures to improve vaccination coverage further and eliminate mother-to-child transmission by coordinated programming with other services offering additional HBV interventions will help move towards the global goal of hepatitis B elimination by 2030.Funding: As per sources of funding.     

Ending risk-group HBV vaccination for MSM after the introduction of universal infant HBV vaccination: A mathematical modelling study

BackgroundRisk-group HBV vaccination for men who have sex with men (MSM) was introduced in the Netherlands in 2002, followed by universal infant vaccination in 2011, that will enable termination of risk-group vaccination over time. The introduction of pre-exposure prophylaxis (PrEP) for HIV prevention might result in increased HBV testing and vaccination against HBV. The aim of this study was to investigate the impact of the transition from risk-group to universal HBV vaccination, accounting for improvements in HBV testing and treatment, as well as the introduction of PrEP.MethodsWe developed a mathematical model for HBV transmission among MSM. Universal vaccination was modelled by assigning some MSM (5–15% in 2028 increasing to 80–90% in 2033 and thereafter) to be vaccinated when they become sexually active. We investigated different scenarios assuming 0.5% extra vaccination rate and 0.5% extra testing rate due to PrEP consultations; and 5% of HIV-negative MSM on PrEP, that will reduce the probability of HBV acquisition by 88%.ResultsUniversal vaccination resulted in a reduction of 24% (interquartile range; 22–25%) of the total number of HBV infections among MSM estimated to occur from 2020 to 2070. With universal vaccination, terminating risk-group vaccination in 2030 or 2040 resulted in 30% or 10% more HBV infections over 2020–2070, respectively, compared to continuation of risk-group vaccination until 2070. With PrEP and continued risk-group vaccination, the total number of HBV infections over 2020–2070 was reduced by 13%.ConclusionsUniversal HBV vaccination can lead to a major reduction in HBV incidence among MSM in the future. The reduction becomes smaller when ending risk-group HBV vaccination, but larger by PrEP use for HIV prevention. Efforts to keep high levels of HBV vaccination, testing, and treatment have to be continued in the coming decades in order to eliminate HBV as a health threat for MSM.     

Uptake of Mpox vaccination among transgender people and gay,bisexual and other men who have sex with men among sexually-transmitted infection clinic clients in Vancouver,British Columbia

ObjectivesAs the primary public health strategy for controlling the 2022 Mpox outbreak, it is critical to evaluate the impact of Mpox vaccination campaigns for transgender people and gay, bisexual and other men who have sex with men (T/GBM). We measured vaccine uptake and associated factors among T/GBM clients of an urban STI clinic in British Columbia (BC).MethodsWe conducted a cross-sectional online survey between August 8–22, 2022 of clients who had attended the STI clinic, 5–7 weeks following the first-dose Mpox vaccination campaign in BC. We drew on a systematic review of factors associated with vaccine uptake to develop survey questions, and measured vaccine uptake among vaccine-eligible T/GBM.ResultsOverall, 51% of T/GBM had received the first dose of the vaccine. The sample (331 participants) was majority White and university educated, identified as a man and gay, 10% had trans experience, and 68% met eligibility criteria for vaccination. Among vaccine-eligible participants identifying as T/GBM, 66% had been vaccinated; being unvaccinated was more common among participants identifying as bisexual or heteroflexible/mostly straight, and who spent less time with other T/GBM. Eligible yet unvaccinated participants had lower perceived susceptibility, and reported fewer cues to action (e.g., fewer saw information promoting the vaccine), and increased constraints to vaccine access; vaccine barriers related to accessing clinics and privacy were common. The majority (85%) of those eligible and unvaccinated at time of survey were willing to receive the vaccine.ConclusionIn this sample of STI clinic clients, vaccine uptake among eligible T/GBM was high in the initial weeks following a Mpox vaccination campaign. However, uptake was patterned on social gradients with lower uptake among T/GBM who may be less effectively engaged by available promotion channels. We recommend early, intentional and diverse engagement of T/GBM populations in Mpox and other targeted vaccination programs.     

Prevalence of indications for adult hepatitis A vaccination among hepatitis A outbreak-associated cases,Three US States, 2016–2019

BackgroundSafe and effective hepatitis A vaccines have been recommended in the United States for at-risk adults since 1996; however, adult vaccination coverage is low.MethodsAmong a random sample of adult outbreak-associated hepatitis A cases from three states that were heavily affected by person-to-person hepatitis A outbreaks, we assessed the presence of documented Advisory Committee on Immunization Practices (ACIP) indications for hepatitis A vaccination, hepatitis A vaccination status, and whether cases that were epidemiologically linked to an outbreak-associated hepatitis A case had received postexposure prophylaxis (PEP).ResultsOverall, 74.1% of cases had a documented ACIP indication for hepatitis A vaccination. Fewer than 20% of epidemiologically linked cases received PEP.ConclusionsEfforts are needed to increase provider awareness of and adherence to ACIP childhood and adult hepatitis A vaccination and PEP recommendations in order to stop the current person-to-person hepatitis A outbreaks and prevent similar outbreaks in the future.     

Hepatitis A antibody persistence 8 and 10 years after 1-dose and 2-dose vaccination in children from Panama

BackgroundHepatitis A virus (HAV) remains a global public health concern, which is potentially growing in Latin America, due to an expected shift from high to intermediate endemicity levels. The use of HAV vaccines in pediatric national immunization programs (NIPs), either as a 2-dose or a 1-dose schedule, has been explored in Latin American countries; however, evidence demonstrating long-term protection in this population is limited in the region. We evaluated long-term antibody persistence following a 1-dose partial series and the recommended 2-dose schedule used in Panama’s pediatric NIP.MethodsTwo independent cross-sectional serological surveys were conducted at year 8 (Y8) and Y10 following vaccination under the NIP with 1 or 2 doses of an inactivated HAV vaccine (Havrix, GSK). Seropositivity (anti-HAV antibody concentration ≥ 15 mIU/mL) rates and antibody geometric mean concentrations (GMCs) were assessed at each serosurvey. Non-inferiority of 1 dose versus 2 doses was also explored.ResultsThis study (NCT02712359) included 600 and 599 children at Y8 and Y10 post-vaccination, respectively. Seropositivity rates were 74.3% (95% confidence interval [CI]: 69.0; 79.2) and 97.7% (95% CI: 95.3; 99.1) at Y8 and 71.9% (95% CI: 66.4; 76.9) and 96.3% (95% CI: 93.5; 98.2) at Y10, in the 1-dose and 2-dose groups, respectively. Antibody GMCs were lower in the 1-dose versus the 2-dose group in both surveys. Non-inferiority was not demonstrated since the lower limit of the 2-sided 95% CI for the between-group difference in seropositivity rates (1-dose minus 2-dose) was < ?10%.ConclusionAnti-HAV antibody persistence was observed in lower percentages of children receiving 1 dose versus 2 doses of Havrix, at 8 and 10 years post-vaccination in Panama. Further investigations are needed to confirm antibody persistence and conclude on the protection afforded beyond 10 years in the pediatric population in Latin America.     

Post-vaccination HPV seroprevalence among female sexual health clinic attenders in England

BackgroundThe National HPV Immunisation Programme was introduced in England in September 2008 using the HPV16/18 bivalent vaccine. We conducted serological surveillance to explore vaccination coverage levels. We also conducted a case-control study to investigate a hypothesised cross-protective effect of the HPV16/18 vaccine against genital warts.MethodsResidual serum specimens from 16 to 20 year-old women attending six specialist sexual health services (SSHS) between 2011 and 2015 in England were tested for antibodies against HPV16 and HPV18 using a virus-like particle (VLP)-based multiplex serology assay. Patients were classified as having vaccine-induced seropositivity if they were seropositive for both HPV types and either had high antibody levels for at least one HPV type, or moderately high levels for both HPV types.Differences in vaccine-induced seropositivity by patient characteristics were investigated using logistic regression. Vaccine-induced seropositivity was then compared for patients with genital warts (cases) and matched patients without (controls).ResultsOf 3,973 serum specimens collected, 3,870 (97.4%) had a valid result. The proportion of women with vaccine-induced seropositivity decreased with age (from 78.1% in 16-year-olds to 52.6% in 20-year-olds). Vaccine-induced seropositivity was lower among women born outside the UK, from more deprived areas and with a history of chlamydia diagnosis. A difference in uptake by ethnic group was also seen but this was largely confounded by differences in deprivation and country of birth. Among 537 cases and 1,515 controls, there was little evidence of a protective effect of the bivalent HPV vaccine against genital warts (adjusted odds ratio 0.93; 95% CI: 0.74–1.18).DiscussionVaccine-induced seropositivity in this high-risk population was in line with vaccination coverage in the general population although was lower in some at-risk sub-groups. This study does not provide evidence to support a cross-protective effect of the HPV16/18 vaccine against genital warts.     

Human papillomavirus vaccination coverage among men who have sex with men—National HIV Behavioral Surveillance,United States, 2017

Men who have sex with men (MSM) are at high risk for infections and diseases caused by human papillomavirus (HPV), many of which are vaccine-preventable. In the United States, routine HPV vaccination has been recommended for adolescent males since 2011. This analysis evaluated self-reported receipt of ≥ 1 HPV vaccine dose by age group and HIV status among adult MSM using 2017 data from National HIV Behavioral Surveillance (NHBS) and compared the proportion vaccinated to prior years. Among 10,381 MSM aged ≥ 18 years, 17.9% of MSM overall and 28.4% of MSM living with HIV reported any HPV vaccination. Among 2,482 MSM aged 18–26 years, 32.8% overall and 51.3% living with HIV reported HPV vaccination. Since 2011, the proportion of MSM aged 18–26 years reporting HPV vaccination has increased over six-fold. As vaccinated adolescents age into young adults, coverage will continue to increase overall, including among MSM.     

The impact of the COVID-19 pandemic on hepatitis B virus vaccination and transmission among men who have sex with men: A mathematical modelling study

BackgroundDuring the COVID-19 pandemic, the number of hepatitis B virus (HBV) vaccinations among men who have sex with men (MSM) has been considerably lower than before the pandemic. Moreover, less frequent HBV testing and a reduction in numbers of sex partners have been reported. We assessed the impact of these COVID-19-related changes on HBV transmission among MSM in the Netherlands.MethodsWe estimated the changes in sexual activity, HBV testing, and HBV vaccination among MSM during the pandemic from Dutch data. We used a deterministic compartmental model and investigated scenarios with small or large declines in sexual activity, testing, and vaccination for the current phase of the pandemic (without available data). We examined the increase in HBV vaccinations needed to prevent further increase in HBV incidence.ResultsWith a decrease in numbers of sex partners of 15–25% during the first lockdown and 5% during the second lockdown, we found a decline of 6.6% in HBV incidence in 2020, despite a >70% reduction in HBV testing and vaccination during the first lockdown. With numbers of sex partners rebounding close to pre-pandemic level in 2021, and a reduction of 15% in testing and 30% in vaccination in 2021, we found an increase of 1.4% in incidence in 2021 and 3.1% in 2026. With these changes, an increase of ≥60% in HBV vaccinations in 2022 would be needed to bring the HBV incidence in 2023 back to the level that it would have had if the COVID-19-related changes had not occurred.ConclusionsDespite reductions in sexual activity during the COVID-19 pandemic, the decrease in HBV vaccinations may result in a small increase in HBV incidence after 2021, which may persist for years. It is important to restore the vaccination level and limit further increase in HBV transmission among MSM.     

Rural,urban, and suburban differences in influenza vaccination coverage among children

Influenza vaccination is the primary way to prevent influenza, yet influenza vaccination coverage remains low in the United States. Previous studies have shown that children residing in rural areas have less access to healthcare and lower vaccination coverage for some vaccines. Influenza vaccination coverage among children 6 months–17 years by rural/urban residence during the 2011–12 through 2018–19 influenza seasons was examined using National Immunization Survey-Flu data. The Council of American Survey Research Organizations response rates for National Immunization Survey-Flu ranged from 48% to 65% (2011–12 through the 2017–18 seasons) for the landline sample and 20%–39% (2011–12 through the 2018–19 seasons) for the cellular telephone sample. Children residing in rural areas had influenza vaccination coverage that ranged from 7.9 (2012–13 season) to 12.6 (2016–17 season) percentage points lower than children residing in urban areas, and ranged from 4.5 (2012–13 season) to 7.4 (2016–17 season) percentage points lower than children residing in suburban areas. The differences in influenza vaccination coverage among rural, suburban, and urban children were consistent over the eight seasons studied. Lower influenza vaccination coverage was observed among rural children regardless of child’s age, mother’s education, household income, or number of children under 18 years of age in the household. Rural versus urban and suburban differences in influenza vaccination coverage remained statistically significant while adjusting for selected sociodemographic characteristics. A better understanding of the reasons for lower childhood influenza vaccination coverage for children in rural and suburban areas is needed.     

Prevalence of influenza-specific vaccination hesitancy among adults in the United States, 2018

BackgroundThe role of vaccine hesitancy on influenza vaccination is not clearly understood. Low influenza vaccination coverage in U.S. adults suggests that a multitude of factors may be responsible for under-vaccination or non-vaccination including vaccine hesitancy. Understanding the role of influenza vaccination hesitancy is important for targeted messaging and intervention to increase influenza vaccine confidence and uptake. The objective of this study was to quantify the prevalence of adult influenza vaccination hesitancy (IVH) and examine association of IVH beliefs with sociodemographic factors and early-season influenza vaccination.MethodsA four-question validated IVH module was included in the 2018 National Internet Flu Survey. Weighted proportions and multivariable logistic regression models were used to identify correlates of IVH beliefs.ResultsOverall, 36.9% of adults were hesitant to receive an influenza vaccination; 18.6% expressed concerns about vaccination side effects; 14.8% personally knew someone with serious side effects; and 35.6% reported that their healthcare provider was not the most trusted source of information about influenza vaccinations. Influenza vaccination ranged from 15.3 to 45.2 percentage points lower among adults self-reporting any of the four IVH beliefs. Being female, age 18–49 years, non-Hispanic Black, having high school or lower education, being employed, and not having primary care medical home were associated with hesitancy.ConclusionsAmong the four IVH beliefs studied, being hesitant to receiving influenza vaccination followed by mistrust of healthcare providers were identified as the most influential hesitancy beliefs. Two in five adults in the United States were hesitant to receive an influenza vaccination, and hesitancy was negatively associated with vaccination. This information may assist with targeted interventions, personalized to the individual, to reduce hesitancy and thus improve influenza vaccination acceptance.     

Influenza vaccination and respiratory virus interference among Department of Defense personnel during the 2017–2018 influenza season

PurposeReceiving influenza vaccination may increase the risk of other respiratory viruses, a phenomenon known as virus interference. Test-negative study designs are often utilized to calculate influenza vaccine effectiveness. The virus interference phenomenon goes against the basic assumption of the test-negative vaccine effectiveness study that vaccination does not change the risk of infection with other respiratory illness, thus potentially biasing vaccine effectiveness results in the positive direction. This study aimed to investigate virus interference by comparing respiratory virus status among Department of Defense personnel based on their influenza vaccination status. Furthermore, individual respiratory viruses and their association with influenza vaccination were examined.ResultsWe compared vaccination status of 2880 people with non-influenza respiratory viruses to 3240 people with pan-negative results. Comparing vaccinated to non-vaccinated patients, the adjusted odds ratio for non-flu viruses was 0.97 (95% confidence interval (CI): 0.86, 1.09; p = 0.60). Additionally, the vaccination status of 3349 cases of influenza were compared to three different control groups: all controls (N = 6120), non-influenza positive controls (N = 2880), and pan-negative controls (N = 3240). The adjusted ORs for the comparisons among the three control groups did not vary much (range: 0.46–0.51).ConclusionsReceipt of influenza vaccination was not associated with virus interference among our population. Examining virus interference by specific respiratory viruses showed mixed results. Vaccine derived virus interference was significantly associated with coronavirus and human metapneumovirus; however, significant protection with vaccination was associated not only with most influenza viruses, but also parainfluenza, RSV, and non-influenza virus coinfections.     

Japanese encephalitis vaccination in pregnancy among U.S. active duty military women

IntroductionJapanese encephalitis (JE) vaccine is an inactivated vaccine that has shown no risks in pregnancy in animal models, but epidemiologic studies are lacking. U.S. military service members located in JE endemic regions are required to be vaccinated; understanding the potential adverse events (AEs), including AEs that may occur in pregnancy, is needed. Here, we assessed pregnancy and infant health outcomes in association with JE vaccination in pregnancy.MethodsThe study population consisted of 192,570 pregnancies to active duty women (2003–2014), captured in the Department of Defense Birth and Infant Health Research program. JE vaccine in pregnancy, vaccine count, formulation, trimester, and whether first career dose coincided with pregnancy were compared with unexposed pregnancies to assess risk of pregnancy and infant health outcomes. Adjusted risk estimates and 95% confidence intervals (CIs) were calculated by multivariable models.ResultsOf the 192,570 identifed pregnancies, 513 were exposed to the JE vaccine; 474 exposures occurred in the first trimester. For all outcomes, elevated risk estimates ranging from 1.53 to 1.70, were observed with receipt of >1 JE vaccine in pregnancy, though 95% CIs were wide and encompassed the null. First dose of JE vaccination in pregnancy was associated with a 1.87 (95% CI: 1.12–3.13) times increased risk of low birthweight (LBW) when excluding pregnancies exposed to other non-routinely recommended vaccinations in pregnancy. All other associations were null in both main and subset analyses.ConclusionsThe overall results of these analyses provide reassuring findings for the safety of JE vaccination in pregnancy. Higher counts of JE vaccine received in pregnancy yielded large yet non-statistically significant risk estimates for all outcomes, though likely driven by lack of pregnancy awareness. An association was observed with LBW in subset analyses, but it was limited to women receiving their first JE vaccine and not observed in the larger main analyses.     

Sex and age as determinants of the seroprevalence of anti-measles IgG among European healthcare workers: A systematic review and meta-analysis

IntroductionThe international literature shows good evidence of a significant rate of measles susceptibility among healthcare workers (HCWs). As such, they are an important public health issue.MethodsWe conducted a systematic review and meta-analysis to estimate the prevalence of susceptible HCWs in EU/EEA countries and in the UK and to explore the characteristics (sex and age differences) and management of those found to be susceptible.ResultsNineteen studies were included in the meta-analysis. The prevalence of measles-susceptible HCWs was 13.3% (95 %CI: 10.0–17.0%). In a comparison of serosusceptible female vs. male HCWs, the RR was 0.92 (95 %CI = 0.83–1.03), and in a comparison of age classes (born after vs. before 1980) the RR was 2.78 (95 %CI = 2.20–3.50). The most recent studies proposed the mandatory vaccination of HCWs.DiscussionAccording to our meta-analysis, the prevalence of serosusceptible European HCWs is 13%; HCWs born in the post-vaccination era seem to be at higher risk. Healthcare professionals susceptible to measles are a serious epidemiological concern. Greater efforts should therefore be made to identify those who have yet to be vaccinated and actively encourage their vaccination.     

Anal human papillomavirus among men who have sex with men in three metropolitan cities in southern China: implications for HPV vaccination

IntroductionMen who have sex with men (MSM), especially those infected with human immunodeficiency virus (HIV), are at disproportionate risk for human papillomavirus (HPV) infection. Data about anal HPV prevalence among MSM in southern China are limited.MethodsMSM were recruited between January 1 and August 31, 2017 in three metropolitan cities: Guangzhou, Shenzhen and Wuxi. A self-completed tablet-based questionnaire was used to collect information about socio-demographic/sexual behavioral characteristics, history of sexually transmitted infections (STIs) and recreational drug use. An anal brush was used to collect exfoliated cells for HPV DNA testing and genotyping, and a blood sample was taken for HIV testing. Penile/anal warts were checked by a clinician.ResultsA total of 536 MSM were enrolled, including 39 HIV-positive and 497 HIV-negative individuals. Compared with HIV-negative MSM, prevalence of any HPV genotype (79.5% vs 46.7%), any high-risk genotype (64.1% vs 36.6%) and any nonavalent vaccine-preventable genotype (53.9% vs 31.6%) was significantly higher in HIV-positive MSM, with all P < 0.01. HIV infection (adjusted odds ratio [AOR], 4.28; 95% confidence interval [CI], 1.87–9.80), using recreational drugs (AOR, 1.87; 95% CI, 1.22–2.87), having ≥ 3 years of sexual experience (AOR, 1.52; 95% CI, 1.01–2.28), having ≥ 6 lifetime male partners (AOR, 1.92; 95% CI, 1.29–2.86), and engaging receptive anal intercourse (AOR, 2.30; 95% CI, 1.48–3.57) were associated with higher anal HPV prevalence. Any HPV prevalence increased with age, from 24.5% at < 20 years to 55.8% at ≥ 40 years.ConclusionsAnal HPV prevalence was high among MSM in southern China, significantly associated with HIV status and sexual experience. HPV prevalence increased with age among MSM. A targeted HPV vaccination program for teenage MSM might be necessary. Our findings will inform targeted HPV modelling among MSM in China.     

Impact of prior vaccination on antibody response and influenza-like illness among Australian healthcare workers after influenza vaccination in 2016

BackgroundEpidemiological studies suggest that influenza vaccine effectiveness decreases with repeated administration. We examined antibody responses to influenza vaccination among healthcare workers (HCWs) by prior vaccination history and determined the incidence of influenza infection.MethodsHCWs were vaccinated with the 2016 Southern Hemisphere quadrivalent influenza vaccine. Serum samples were collected pre-vaccination, 21–28 days and 7 months post-vaccination. Influenza antibody titres were measured at each time-point using the haemagglutination inhibition (HI) assay. Immunogenicity was compared by prior vaccination history.ResultsA total of 157 HCWs completed the study. The majority were frequently vaccinated, with only 5 reporting no prior vaccinations since 2011. Rises in titres for all vaccine strains among vaccine-naïve HCWs were significantly greater than rises observed for HCWs who received between 1 and 5 prior vaccinations (p < 0.001, respectively). Post-vaccination GMTs against influenza A but not B strains decreased as the number of prior vaccinations increased from 1 to 5. There was a significant decline in GMTs post-season for both B lineages. Sixty five (41%) HCWs reported at least one influenza-like illness episode, with 6 (4%) identified as influenza positive.ConclusionsVarying serological responses to influenza vaccination were observed among HCWs by prior vaccination history, with vaccine-naïve HCWs demonstrating greater post-vaccination responses against A(H3N2).     

COVID-19 vaccination among different types of US Healthcare Personnel

BackgroundIncreasing vaccine coverage remains the best way to control the COVID-19 pandemic. Healthcare personnel (HCP) have long been the most credible and frequently used source of vaccine information for the public, and an HCP recommendation is a strong predictor of vaccination.MethodsA survey of HCP was conducted in September 2021 via a double opt-in network panel. Responses to survey items were summarized and stratified by HCP type and adjusted logistic regression models were fitted.Results>94% of the 1074 HCP surveyed reported receiving at least one dose of COVID-19 vaccine or intending to soon, with vaccinating most common among pediatricians (98%), followed by family medicine doctors (96%), pharmacists (94%), and nurses/nurse practitioners/physician assistants (88%). HCP with high trust in the Centers for Disease Control and Prevention had 26 times the odds of vaccinating of HCP with low trust (95%CI: 9, 74). Nearly half of unvaccinated HCP (47%) were concerned about side effects, and one third of unvaccinated HCP (33%) were concerned the vaccine was developed too quickly. About three quarters of HCP reported strongly recommending the Pfizer-BioNTech (75%) and Moderna (70%) vaccines to their patients, compared to about one quarter (24%) strongly recommending Johnson & Johnson.ConclusionsAlthough most HCP are vaccinated against COVID-19 and strongly recommend vaccination to their patients, some harbor similar concerns to the public. Additional resources – regularly updated to explain the progressing scientific landscape and address ever evolving public concerns – are needed to further improve vaccine coverage among HCP and aid them in supporting the decision-making of their patients.     

Meningococcal B vaccination coverage among older adolescents in the United States

BackgroundSerogroup B meningococcal (MenB) vaccination recommendations for adolescents in the United States (US) include routine vaccination for all individuals at increased risk and vaccination for individuals not at increased risk aged 16–23 years (preferred age 16–18 years) based on shared clinical decision-making. The two licensed MenB vaccines require administration of ≥2 doses.MethodsThis cross-sectional study analyzed 2017–2018 National Immunization Survey-Teen (NIS-Teen) data to evaluate ≥1 dose and ≥2 dose MenB vaccination coverage among adolescents aged 17 years. Multivariable logistic regression was used to further evaluate determinants of MenB vaccination.ResultsNationally, MenB vaccination coverage among 17-year-olds increased from 14.5% in 2017 to 17.2% in 2018 for ≥1 dose and from 6.3% to 8.4% for ≥2 doses. MenB vaccination coverage (2017–2018) was the lowest in the South (≥1 dose: 14.6%; ≥2 doses: 6.3%) and highest in the Northeast region (18.3% and 9.3%), with variation observed by census division. Adolescents were more likely to have received ≥1 dose of MenB vaccine if they had any Medicaid insurance (odds ratio [OR], 1.77; 95% confidence interval [CI], 1.32–2.39) or had received human papillomavirus (OR, 1.94; 95% CI, 1.41–2.67) or meningococcal A, C, W, and Y (OR, 4.03; 95% CI, 2.92–5.56) vaccinations.ConclusionsMenB first-dose coverage in the US is low, and even lower for a second dose, with regional variation. Being up to date with other routinely administered vaccines increased the likelihood of receiving MenB vaccination.     

Impact of the National Perinatal Hepatitis B Prevention Programme in the Republic of Korea: A retrospective registry-based cohort study

IntroductionHepatitis B is a major preventable cause of morbidity and mortality from chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. We aimed to evaluate the performance and outcomes of the Korean Perinatal Hepatitis B Prevention Programme (PHBPP) and to investigate the impact of the current post-exposure immunoprophylaxis protocol.MethodsA retrospective cohort study was performed based on electronic data registry of infants born to hepatitis B virus (HBV)-infected mothers between July 2002 and 2013.ResultsDuring the study period, 159,983 Korean infants were registered with the PHBPP, with an overall programme coverage of 92.8%. Despite receiving timely post-exposure immunoprophylaxis, 8.6% of infants born to mothers aged <25 years and hepatitis B e antigen (HBeAg)-positive, and 0.7% of infants born to mothers aged ≥25 years and HBeAg-negative were infected. An estimated 14,123 infants were directly protected from perinatal HBV transmission by the PHBPP during the 11.5-year period, at a cost of 1157 US dollars per case averted. The incidence of paediatric hepatocellular carcinoma declined dramatically during the period.ConclusionsA substantial number of infants have been prevented from hepatitis B since the PHBPP was launched in the Republic of Korea. Continued efforts to promote the programme, an integrated approach to maximising its coverage, a risk-stratified strategy, and innovations in logistics could further reduce perinatal HBV transmission.     

Characteristics and incidence of vaccine adverse events after Bacille Calmette–Guérin vaccination: A national surveillance study in Japan from 2013 to 2017

BackgroundJapan amended the recommended age for the Bacille Calmette–Guérin (BCG) vaccination to less than 6 months after 2005, but subsequently amended the recommended age to 5–8 months (latest amendment, <1 year) in April 2013 due to the increasing incidence of BCG-associated osteitis/osteomyelitis since 2005.MethodsWe collected data on BCG-associated vaccine adverse events (VAEs) in the population aged <1 year between April 2013 and March 2017. The incidence of BCG-associated VAE was analyzed using census and vaccine coverage data from the government website. We compared the incidence of VAEs in patients vaccinated at less than 6 months with those vaccinated at 6 months or older.ResultsAmong the 581 BCG-associated VAEs recorded during the study period, 354 (61%) were male, and the average age at vaccination was 5.7 months. The incidence of VAEs per million population aged <1 year at vaccination was highest for suppurative lymphadenitis (63.7), followed by skin lesions (38.4), and BCG-associated osteitis/osteomyelitis (3.1). Disseminated BCG and anaphylaxis were rare (1.1 and 1.6%, respectively). The incidence of VAEs in the population vaccinated at <6 months of age was higher for BCG-associated osteitis/osteomyelitis (3.8) and disseminated BCG (1.3) than in the population vaccinated at ≥6 months.ConclusionsThe population vaccinated at <6 months of age was more likely to develop BCG-associated osteitis/osteomyelitis than the population vaccinated at ≥6 months of age, indicating that the change in the recommended vaccination age in 2013 might have contributed to the subsequent decrease in the incidence of BCG-associated osteitis/osteomyelitis.