Antigen specific vaccine hesitancy in pregnancy.

BACKGROUND: Vaccinations in pregnancy are recommended for the potential benefits of preventing severe pertussis disease in newborns and for preventing the impact of influenza on the pregnant woman, her foetus in utero and, the newborn in the first six months of life. Published data in Australia suggested that coverage rates were sub-optimal so the reasons for this were reviewed. METHODS: A cross-sectional survey of 1014 postnatal women, aged 18 years and older, who had given birth in the previous six months was undertaken on the Gold Coast in Queensland, Australia. Participants completed a brief questionnaire on provided smart tablets at public vaccination clinics or with a researcher by phone or via an on-line link. RESULTS: Just over 85% of survey respondents received a pertussis booster with many of those not receiving vaccine having had it in a recent pregnancy. Only 36.7% of respondents had an influenza vaccine in pregnancy with key barriers being belief in influenza vaccine, seasonality of parturition and a lack of recommendation from the attending obstetric carers. DISCUSSION: While maternal pertussis vaccine programs are a success, work needs to be done to improve the public perception of the risk benefit equation surrounding influenza vaccine in general, and particularly its use in pregnancy. Research is required into approaches to altering practitioner attitudes as well as how to alter public perceptions.

The comparative effectiveness of adjuvanted and unadjuvanted trivalent inactivated influenza vaccine (TIV) in the elderly.

BACKGROUND: Influenza is associated with a high mortality and morbidity in older adults. Vaccination remains the most effective method of preventing influenza and its consequences, however, vaccine effectiveness decreases with increasing age and increasing immunosenescence. In older adults, immunogenicity studies suggest an MF59 adjuvanted influenza vaccine (ATIV, Fluad(®)) may help. METHODS: We evaluated the comparative effectiveness of ATIV, and unadjuvanted trivalent influenza vaccine (TIV) in reducing laboratory confirmed influenza in the elderly. Elderly in three health authorities during winter 2011-12 were included in a community based case control study design. Cases tested positive and controls tested negative for influenza. Subjects with known immunosuppression were excluded. Logistic regression was used to calculate the odds ratio of vaccination (vs. no vaccination) in cases and controls. ATIV and TIV effectiveness was described. RESULTS: A total of 282 eligible participants were enrolled (84 cases). Almost half (136) were in a long term care facility and were 85 years of age or older (132) vaccine effectiveness decreased with increasing age. In a variety of multivariate analyses, ATIV was significantly protective at around 60% (p=0.02), with only residence in long term care and health authority also significant. Vaccine effectiveness increased in non-long term care residents. In multivariate analyses TIV was ineffective. CONCLUSION: An MF59 adjuvanted vaccine provided significantly improved protection against influenza in the elderly.

Protective effect of single-dose adjuvanted pandemic influenza vaccine in children.

BACKGROUND: During the first wave of A/California/7/2009(H1N1) influenza, high rates of hospitalization in children under 5 years were seen in many countries. Subsequent policies for vaccinating children varied in both type of vaccine and number of doses. In Canada, children 36 months to <10 years received a single dose of 0.25 ml of the GSK adjuvanted vaccine (Arepanrix) equivalent to 1.9 microg HA. Children 6 months to 35 months received two doses as did those 36-119 months with chronic medical conditions. METHOD: We conducted a community-based case-control vaccine effectiveness (VE) review of children under 10 years with influenza like illness who were tested for H1N1 infection at the central provincial laboratory. Laboratory-confirmed influenza was the primary outcome, and vaccination status the primary exposure to assess VE after a single 0.25-ml dose. RESULTS: If vaccination was designated to be effective after 14 days, no vaccinated child had laboratory-confirmed influenza compared to 38% of controls. The VE of 100% was statistically significant for children <10 years of age and <5 years considered separately. If vaccination was considered effective after 10 days, VE dropped to 96% overall but was statistically significant and over 90% in all age subgroups, including those under 36 months. CONCLUSIONS: A single 0.25-ml dose of the GSK adjuvanted vaccine (Arepanrix) protects children against laboratory-confirmed pandemic influenza potentially avoiding any increased reactogenicity associated with second doses. Adjuvanted vaccines offer hope for improved seasonal vaccines in the future.