School-Level Variation in Coverage of Co-Administered dTpa and HPV Dose 1 in Three Australian States.

BACKGROUND: Australian adolescents are routinely offered HPV and dTpa (diphtheria, tetanus, pertussis) vaccines simultaneously in the secondary school vaccination program. We identified schools where HPV initiation was lower than dTpa coverage and associated school-level factors across three states. METHODS: HPV vaccination initiation rates and dTpa vaccination coverage in 2016 were calculated using vaccine databases and school enrolment data. A multivariate analysis assessed sociodemographic and school-level factors associated with HPV initiation being >5% absolute lower than dTpa coverage. RESULTS: Of 1280 schools included, the median school-level HPV initiation rate was 85% (interquartile range (IQR):75-90%) and the median dTpa coverage was 86% (IQR:75-92%). Nearly a quarter (24%) of all schools had HPV vaccination initiation >5% lower than dTpa coverage and 11 % had >10% difference. School-level factors independently associated with >5% difference were remote schools (aOR:3.5, 95% CI = 1.7-7.2) and schools in major cities (aOR:1.8, 95% CI = 1.0-3.0), small schools (aOR:3.3, 95% CI = 2.3-5.7), higher socioeconomic advantage (aOR:1.7, 95% CI = 1.1-2.6), and lower proportions of Language-background-other-than-English (aOR:1.9, 95% CI = 1.2-3.0). CONCLUSION: The results identified a quarter of schools had lower HPV than dTpa initiation coverage, which may indicate HPV vaccine hesitancy, and the difference was more likely in socioeconomically advantaged schools. As hesitancy is context specific, it is important to understand the potential drivers of hesitancy and future research needs to understand the reasons driving differential uptake.

Risk of newly detected infections and cervical abnormalities in adult women seropositive or seronegative for naturally acquired HPV-16/18 antibodies.

BACKGROUND: Infections with human papillomavirus (HPV) types 16 and 18 account for ~70% of invasive cervical cancers but the degree of protection from naturally acquired anti-HPV antibodies is uncertain. We examined the risk of HPV infections as defined by HPV DNA detection and cervical abnormalities among women >25 years in the Human Papilloma VIrus Vaccine Immunogenicity ANd Efficacy trial's (VIVIANE, NCT00294047) control arm. METHODS: Serum anti-HPV-16/18 antibodies were determined at baseline and every 12 months in baseline DNA-negative women (N = 2687 for HPV-16 and 2705 for HPV-18) by enzyme-linked immunosorbent assay (ELISA) from blood samples. HPV infections were identified by polymerase chain reaction (PCR) every 6-months, and cervical abnormalities were confirmed by cytology every 12 months. Data were collected over a 7-year period. The association between the risk of type-specific infection and cervical abnormalities and serostatus was assessed using Cox proportional hazard models. RESULTS: Risk of newly detected HPV-16-associated 6-month persistent infections (PI) (hazard ratio [HR] = 0.56 [95%CI:0.32; 0.99]) and atypical squamous cells of undetermined significance (ASC-US+) (HR = 0.28 [0.12; 0.67]) were significantly lower in baseline seropositive vs baseline seronegative women. HPV-16-associated incident infections (HR = 0.81 [0.56; 1.16]) and 12-month PI (HR = 0.53 [0.24; 1.16]) showed the same trend. A similar trend of lower risk was observed in HPV-18-seropositive vs -seronegative women (HR = 0.95 [0.59; 1.51] for IIs, HR = 0.43 [0.16; 1.13] for 6-month PIs, HR = 0.31 [0.07; 1.36] for 12-month PIs, and HR = 0.61 [0.23; 1.61] for ASC-US+). CONCLUSIONS: Naturally acquired anti-HPV-16 antibodies were associated with a decreased risk of subsequent infection and cervical abnormalities in women >25 years. This possible protection was lower than that previously reported in 15- to 25-year-old women.

Pertussis vaccination coverage among Australian women prior to childbirth in the cocooning era: a two-hospital, cross-sectional survey, 2010 to 2013.

BACKGROUND: Recent pertussis epidemics have triggered implementation of cocooning, involving caregiver vaccination to indirectly protecting susceptible infants. AIM: To determine patient, provider and setting factors associated with maternal pertussis booster vaccination (dTpa) within 5-10 years before childbirth. MATERIALS AND METHODS: Cross-sectional survey using Health Belief Model constructs among postpartum women in a tertiary referral centre and a private hospital in Sydney, Australia. RESULTS: Pertussis vaccination was current among 33.7% of the 2483 new mothers (0.5% vaccinated during pregnancy). Women were more likely to be vaccinated if they had heard of 'whooping cough' from a health professional (OR: 2.59, P < 0.001, 95% CI: 1.70-3.95), were recommended the vaccine (OR: 2.48, P < 0.00, 95% CI: 1.55-4.00), perceived pertussis as 'severe' for adults (OR: 1.21, p0.009, 95% CI: 1.05-1.39) and 'common' within their community (OR: 1.38, P < 0.001, 95% CI: 1.18-1.61). They more often agreed that it was their parental responsibility to be vaccinated (OR: 1.61, P = 0.002, 95% CI: 1.19-2.18), and this would help prevent their baby from contracting pertussis (OR: 1.22, P = 0.046, 95% CI: 1.00-1.47). Vaccinated women were less likely to report vaccination barriers: time constraints (OR: 0.75, P < 0.001, 95% CI: 0.66-0.85) and having safety concerns (OR: 0.80, P < 0.001, 95% CI: 0.69-0.92). Additionally, their partners reported three times higher uptake (76% vs 49%; P < 0.001; 95% CI: 2.66-3.85). CONCLUSIONS: Current pertussis vaccination in only one in every three postpartum participants may indicate insufficient coverage to protect newborns. Practitioners are instrumental in raising awareness and addressing vaccine concerns. Integrating vaccination into routine obstetric care, whether antenatally or postnatally, may minimise barriers.