Background: Maternal vaccines against pertussis are not yet recommended in the developing world. Besides unclear burden estimates, another concern is that transplacental transfer of maternal pertussis antibodies could result in attenuation of the immune response to whole cell pertussis (DTwP) primary vaccination series in infants. This study was taken up to determine whether higher levels of maternal pertussis antibodies attenuate immune response of infants to DTwP vaccination series given at 6–10–14 weeks of age. Methodology: A total of 261 pregnant women and their infants from four low-income settlements in Karachi, Pakistan were enrolled in this study. The study endpoints were infant antibody titers for Pertussis toxin (PTx), Filamentous hemagglutinin antigen (FHA), Pertactin (PRN) and Fimbriae type 2/3 (FIM) – from birth through 18 weeks of age. Cord blood or pre-vaccine pertussis antibody titers indicate the concentration of maternal antibodies transferred to infants. Linear regression models were used to determine the association between higher maternal antibody titers and infant immune response to DTwP vaccine. Geometric Mean Ratio (GMR) was calculated as the ratio of infant antibody titers at specified time points against the maternal antibody titers at the time of delivery. Results: At eighteen weeks of age, the adjusted β regression coefficient for PTx was 0.06 (95% CI: -0.49-0.61), FHA 0.02 (95% CI: -0.26 -0.29), PRN 0.02 (95%CI -0.38- 0.43), and FIM 0.17 (95%CI: -0.21-0.54). Among infants who received at least two doses of DTwP vaccine, higher maternal antibody titers did not have any attenuating effect on infant post-immunization antibody titers against all four pertussis antigens. Conclusion: Maternal pertussis antibodies did not attenuate infant's immune response to pertussis antigens in DTwP primary vaccine given at 6–10–14 weeks of age.

Background While national human papillomavirus (HPV) vaccination estimates exist by sex, little is known about HPV vaccination rates by gender identity. Methods We conducted a self-administered, anonymous online cross-sectional survey, with recruitment through Facebook ads, of lesbian, gay, bisexual, and transgender individuals in rural areas of the US. We compared HPV vaccine recommendation and uptake by self-reported sex assigned at birth and current gender identity. Results Six hundred sixty respondents were age eligible for HPV vaccination: 84% reported gender identity aligned with their sex assigned at birth, while 10% reported gender identity the differed from their sex assigned at birth; an additional 6% reported non-binary gender identity. Only 14% of male sex assigned at birth and 44% of female sex assigned at birth received HPV vaccine, similar to estimates by current gender identity. Transgender respondents’ HPV vaccination experience mirrored that of cisgender respondents with regard to sex assigned at birth. Conclusions Providers may base HPV vaccine recommendations on individuals’ sex assigned at birth, which may impact transgender individuals’ vaccine coverage. Future HPV vaccine uptake studies should account for gender identity. With sex-specific catch-up HPV vaccination recommendations, the role of gender identity on provider recommendation and reimbursement needs to be addressed.

In recent years, use of the Internet to obtain vaccine information has increased. Historical data are necessary to evaluate current vaccine information seeking trends in context. Between 2002 and 2003, surveys were mailed to 1,630 parents of fully vaccinated children and 815 parents of children with at least one vaccine exemption; 56.1% responded. Respondents were asked about their vaccine information sources, perceptions of these sources accuracy, and their beliefs about vaccination. Parents who did not view their child’s healthcare provider as a reliable vaccine information source were more likely to obtain vaccine information using the Internet. Parents who were younger, more highly educated, and opposed to school immunization requirements were more likely than their counterparts to use the Internet for vaccine information. Compared to parents who did not use the Internet for vaccine information, those who sought vaccine information on the Internet were more likely to have lower perceptions of vaccine safety (adjusted odds ratio (aOR), 1.66; 95% CI, 1.18–2.35), vaccine effectiveness (aOR, 1.83; 95% CI, 1.32–2.53), and disease susceptibility (aOR, 2.08; 95% CI, 1.49–2.90) and were more likely to have a child with a nonmedical exemption (aOR 3.53, 95% CI, 2.61–4.76). These findings provide context to interpret recent vaccine information seeking research.

Despite the existence of human papilloma virus (HPV) vaccines with demonstrated safety and effectiveness and funded HPV vaccination programs, coverage rates are persistently lower and cervical cancer burden higher among Canadian Indigenous peoples. Barriers and supports to HPV vaccination in Indigenous peoples have not been systematically documented, nor have interventions to increase uptake in this population. This protocol aims to appraise the literature in Canadian and global Indigenous peoples, relating to documented barriers and supports to vaccination and interventions to increase acceptability/uptake or reduce hesitancy of vaccination. Although HPV vaccination is the primary focus, we anticipate only a small number of relevant studies to emerge from the search and will, therefore, employ a broad search strategy to capture literature related to both HPV vaccination and vaccination in general in global Indigenous peoples. Methods: Eligible studies will include global Indigenous peoples and discuss barriers or supports and/or interventions to improve uptake or to reduce hesitancy, for the HPV vaccine and/or other vaccines. Primary outcomes are documented barriers or supports or interventions. All study designs meeting inclusion criteria will be considered, without restricting by language, location, or data type. We will use an a priori search strategy, comprised of key words and controlled vocabulary terms, developed in consultation with an academic librarian, and reviewed by a second academic librarian using the PRESS checklist. We will search several electronic databases from date of inception, without restrictions. A pre-defined group of global Indigenous websites will be reviewed for relevant gray literature. Bibliographic searches will be conducted for all included studies to identify relevant reviews. Data analysis will include an inductive, qualitative, thematic synthesis and a quantitative analysis of measured barriers and supports, as well as a descriptive synthesis and quantitative summary of measures for interventions. Discussion: To our knowledge, this study will contribute the first systematic review of documented barriers, supports, and interventions for vaccination in general and for HPV vaccination. The results of this study are expected to inform future research, policies, programs, and community-driven initiatives to enhance acceptability and uptake of HPV vaccination among Indigenous peoples. Systematic review registration: PROSPERO Registration Number: CRD42017048844.

Background Anaphylaxis is a potentially life-threatening allergic reaction. The risk of anaphylaxis after vaccination has not been well described in adults or with newer vaccines in children. Objective We sought to estimate the incidence of anaphylaxis after vaccines and describe the demographic and clinical characteristics of confirmed cases of anaphylaxis. Methods Using health care data from the Vaccine Safety Datalink, we determined rates of anaphylaxis after vaccination in children and adults. We first identified all patients with a vaccination record from January 2009 through December 2011 and used diagnostic and procedure codes to identify potential anaphylaxis cases. Medical records of potential cases were reviewed. Confirmed cases met the Brighton Collaboration definition for anaphylaxis and had to be determined to be vaccine triggered. We calculated the incidence of anaphylaxis after all vaccines combined and for selected individual vaccines. Results We identified 33 confirmed vaccine-triggered anaphylaxis cases that occurred after 25,173,965 vaccine doses. The rate of anaphylaxis was 1.31 (95% CI, 0.90-1.84) per million vaccine doses. The incidence did not vary significantly by age, and there was a nonsignificant female predominance. Vaccine-specific rates included 1.35 (95% CI, 0.65-2.47) per million doses for inactivated trivalent influenza vaccine (10 cases, 7,434,628 doses given alone) and 1.83 (95% CI, 0.22-6.63) per million doses for inactivated monovalent influenza vaccine (2 cases, 1,090,279 doses given alone). The onset of symptoms among cases was within 30 minutes (8 cases), 30 to less than 120 minutes (8 cases), 2 to less than 4 hours (10 cases), 4 to 8 hours (2 cases), the next day (1 case), and not documented (4 cases). Conclusion Anaphylaxis after vaccination is rare in all age groups. Despite its rarity, anaphylaxis is a potentially life-threatening medical emergency that vaccine providers need to be prepared to treat.

In the United States, human papillomavirus vaccination was routinely recommended for adolescent females in 2006 and provisionally recommended for adolescent males in 2009. We evaluated the hypothesis that gender-specific human papillomavirus vaccination recommendations would impact gender-specific uptake of other vaccines using National Immunization Survey-Teen public use data sets (2008-2012). Female adolescents had higher coverage than males of at least 1 other adolescent vaccine in 2008 (3.0% higher) and 2009 (4.3% higher). Gender differences abated in 2010, 2011, and 2012 (0.2%, 0.9%, and 0.4%, respectively). To evaluate unintended consequences of gender-based recommendations, countries with female-only human papillomavirus vaccination recommendations should evaluate gender-specific uptake of other adolescent vaccines.

Background: Kindergarten-entry vaccination requirements have played an important role in controlling vaccine-preventable diseases in the United States. Forty-eight states and the District of Colombia offer nonmedical exemptions to vaccines, ranging in stringency. Methods: We analyzed state-level exemption data from 2011 to 2012 through 2015 to 2016 school years. States were categorized by exemption ease and type of exemption allowed. We calculated nonmedical exemption rates for each year in the sample and stratified by exemption ease, type, and 2 trend categories: 2011-12 through 2012-13 and 2013-14 through 2015-16 school years. Using generalized estimating equations, we created regression models estimating (1) the average annual change in nonmedical exemption rates and (2) relative differences in rates by state classification. Results: The nonmedical exemption rate was higher during the 2013-2014 through 2015-2016 period (2.25%) compared to 2011-2012 through 2012-2013 (1.75%); more importantly, the average annual change in the latter period plateaued. The nonmedical exemption rate in states allowing philosophical and religious exemptions was 2.41 times as high as in states allowing only religious exemptions (incidence rate ratio = 2.41; 95% confidence interval, 1.71-3.41). Conclusions: There was an increase in nonmedical exemption rates through the 2012-2013 school year; however, rates stabilized through the 2015-2016 school year, showing an important shift in trend.

Objective To document Georgian physician’s knowledge, attitudes, and practices concerning HPV, Pap smear testing, and HPV vaccination, and to assess whether physician practice might change with additional education and training. Methods A cross-sectional study was conducted using a self-administered written survey of 288 physicians practicing in 7 healthcare institutions in Tbilisi, Rustavi, and Batumi, Georgia. Data were collected on demographics, conduct of and perceived barriers to Pap smear testing, knowledge about HPV and HPV vaccination, and willingness to receive education and training about HPV and cervical cancer. Univariate counts and proportions were calculated. Pap smear testing and barriers were compared across demographics using bivariate and Poisson regression with robust error variance methods. Results Overall, 54% of physicians never performed Pap smears; most reported testing was not their responsibility. Most (88%) obstetricians/gynecologists performed Pap smears. Younger physicians were more likely to perform Pap smears. Approximately 48% of physicians actively offered the HPV vaccine. Most physicians were receptive to increased education and training about HPV and cervical cancer. Conclusion Age-related differences in the conduct of and attitudes toward Pap smear testing exist among Georgian physicians. There is an opportunity to increase Pap smear testing and provide evidence-based HPV vaccine counseling in Georgia.

Vaccination is a safe and effective way to prevent Human Papillomavirus (HPV) infection and related cancers; however, HPV vaccine uptake remains low in the US. After the 2011 Advisory Committee on Immunization Practices (ACIP) recommendation for routine HPV vaccination of adolescent males, several studies have examined predictors for initiating the vaccine series in this population of interest, particularly with regard to provider recommendations. This study examined racial and ethnic differences for HPV vaccine initiation and provider recommendation in male adolescents. Based on prior HPV vaccine uptake estimates and healthcare utilization data, we hypothesized that minority adolescents would be more likely to initiate HPV vaccines, but less likely to receive a provider recommendation compared to white counterparts. We analyzed the 2014 National Immunization Survey-Teen (NIS-Teen), which included 10,753 male adolescents with provider-verified vaccination data in 50 US states, using multivariate logistic regression models to evaluate racial/ethnic differences in HPV vaccine initiation and provider recommendation. The odds of HPV vaccine initiation were 76 percent higher for Hispanic adolescents and 43 percent higher for non-Hispanic Other or Multiple race adolescents compared to white adolescents. Approximately half of parents reported receiving a provider recommendation for vaccination, with no significant difference in the odds of receiving a provider recommendation across racial/ethnic groups. Despite similar frequency of recommendations across racial and ethnic groups, male adolescents who are racial/ethnic minorities are more likely to initiate vaccination. Future research should focus on developing tailored interventions to increase HPV vaccine receipt among males of all racial/ethnic groups.

Background and objectives: Vaccination with Human Papillomavirus (HPV) vaccine is recommended for 11–12 years-old, but uptake is suboptimal. Current messaging focuses on HPV infection transmission and prevention. Parents and providers are often uncomfortable discussing sexual practices of adolescents, contributing to the delay/refusal of vaccine. We created a cervical cancer-salient message encouraging HPV vaccination, emphasizing disease salience and disease threat, while promoting self-efficacy. We hypothesized this message would have greater effects on vaccine confidence and intent to vaccinate compared to Centers for Disease Control and Prevention (CDC) and non-vaccine control messages. Methods: A 3-arm randomized trial was conducted. Parents of girls aged 9–17 were eligible for the study. We measured participants’ vaccine confidence and intent to vaccinate at baseline and post intervention message. Recruitment and surveys were administered online through Amazon Mechanical Turk. Results: 762 participants completed both surveys. We saw modest increases in vaccine confidence when comparing cervical cancer arm and control arm, and CDC arm and control arm; estimates were not statistically significant. The odds of reporting intent to vaccinate among the cervical cancer message arm were 1.13 times the odds of reporting intent to vaccinate in the control arm (95% CI: 0.30. 4.29). Intent to vaccinate was also not statistically significantly different between CDC message arm and control arm (OR = 1.25, 95%CI: 0.66, 2.37). Conclusion: Neither message had effect on intent to vaccinate, highlighting need for research to identify successful messaging strategies for HPV. Exploratory analyses suggest among parents with ‘Low’ vaccine confidence at baseline, the cervical cancer framed message may be more effective in changing intention than the CDC message or non-vaccine control. Future work should target groups with ‘Low’ or ‘Medium’ vaccine confidence at baseline - they may be more amenable to change, and more receptive to disease-salient messaging.