Vaccination coverage for seasonal influenza among residents and health care workers in Norwegian nursing homes during the 2012/13 season, a cross-sectional study.

BACKGROUND: WHO has set a goal of 75% vaccination coverage (VC) for seasonal influenza for residents and also recommends immunization for all healthcare workers (HCWs) in nursing homes (NHs). We conducted a cross-sectional study to estimate the VC for seasonal influenza vaccination in Norwegian NHs in 2012/2013 since the VC in NHs and HCWs is unknown. METHODS: We gathered information from NHs concerning VC for residents and HCWs, and vaccination costs for HCWs, using a web-based questionnaire. We calculated VC among NH residents by dividing the number of residents vaccinated by the total number of residents for each NH. VC among HCWs was similarly calculated by dividing the number of HCWs vaccinated by the total number of HCWs for each NH. The association between VC and possible demographic variables were explored. RESULTS: Of 910 NHs, 354 (38.9%) responded. Median VC per NH was 71.7% (range 0-100) among residents and 0% (range 0-100) among HCWs, with 214 (60%) NHs reporting that none of their HCWs was vaccinated. Median VC for HCWs in NHs with an annual vaccination campaign was 0% (range 0-53), compared to when they did not have an annual vaccination campaign 0% (range 0-12); the distributions in the two groups differed significantly (Mann-Whitney U, P = 0.006 two tailed). CONCLUSION: Median influenza VC in Norwegian NHs was marginally lower than recommended among residents and exceptionally low among HCWs. The VC in HCWs was significantly higher when NHs had an annual vaccination campaign. We recommend that NHs implement measures to increase VC among residents and HCWs, including vaccination campaigns and studies to identify potential barriers to vaccination.

Indirect effect of conjugate pneumococcal vaccination in a 2+1 dose schedule.

In 2006, the heptavalent pneumococcal conjugate vaccine (PCV7) was introduced in the Norwegian Childhood Vaccination Programme in a 2+1 dose schedule; immunisations are administered at 3, 5 and 12 months. Changes in invasive pneumococcal disease in all ages from the baseline years 2004-2005 to 2008 were assessed, focusing on the indirect effect in the unvaccinated population. Following the introduction of PCV7, incidence rates of IPD caused by vaccine serotypes declined across all age groups, the decline being statistically significant for the age groups <5 years, 5-19 years, 40-64 years and > or = 65 years. In the unvaccinated population aged > or = 5 years the incidence rate of IPD caused by PCV7 serotypes declined by 48% from 12.34 cases/100,000 population to 6.44 cases/100,000 population, accounting for 74% of prevented cases of IPD in 2008. Among the adults aged > or = 65 years the incidence rate of IPD caused by serotypes not included in PCV7 increased. No vaccine failure was identified, indicating a very high effectiveness of the 2+1 dose schedule vaccination programme.

Effectiveness of a 2+1 dose schedule pneumococcal conjugate vaccination programme on invasive pneumococcal disease among children in Norway.

The 7-valent pneumococcal conjugate vaccine (PCV-7) was licensed in Norway in 2001. In July 2006, PCV-7 was introduced in the Norwegian Childhood Vaccination Programme in a 2+1 dose schedule, with immunizations administered at 3, 5 and 12 months of age. PCV-7 was offered through the vaccination programme to all children born from January 2006, i.e. a catch-up for children aged 3-6 months. Prior to 2006 the use of PCV-7 was negligible. The effectiveness of the PCV-7 vaccination programme was assessed using data on invasive pneumococcal disease (IPD) incidence obtained from the Norwegian Surveillance System for Communicable Diseases, serotype distribution from the National Reference Laboratory for Pneumococci, and vaccine coverage and vaccination status from the Norwegian National Vaccination Register. Vaccine coverage quickly reached high levels; 95% of children >3 months born from January 2006 had received at least one immunization with PCV-7. The incidence rate of IPD among children <2 years rapidly declined; the rate of vaccine serotype IPD in this age group fell from an average of 47.1 cases/100,000 population in the 2 years prior to PCV-7 introduction to 13.7 cases/100,000 population in 2007. The incidence rate of nonvaccine serotype IPD remained stable. The vaccine programme effectiveness was estimated to be 74% (95% CI 57-85%). No vaccine failure was seen after complete primary immunization with two vaccine doses. Our findings indicate that PCV-7 provides highly effective protection against vaccine serotype IPD when administered in a 2+1 dose schedule.