Effect of vaccines and antivirals during the major 2009 A(H1N1) pandemic wave in Norway--and the influence of vaccination timing.

To evaluate the impact of mass vaccination with adjuvanted vaccines (eventually 40% population coverage) and antivirals during the 2009 influenza pandemic in Norway, we fitted an age-structured SEIR model using data on vaccinations and sales of antivirals in 2009/10 in Norway to Norwegian ILI surveillance data from 5 October 2009 to 4 January 2010. We estimate a clinical attack rate of approximately 30% (28.7-29.8%), with highest disease rates among children 0-14 years (43-44%). Vaccination started in week 43 and came too late to have a strong influence on the pandemic in Norway. Our results indicate that the countermeasures prevented approximately 11-12% of potential cases relative to an unmitigated pandemic. Vaccination was found responsible for roughly 3 in 4 of the avoided infections. An estimated 50% reduction in the clinical attack rate would have resulted from vaccination alone, had the campaign started 6 weeks earlier. Had vaccination been prioritized for children first, the intervention should have commenced approximately 5 weeks earlier in order to achieve the same 50% reduction. In comparison, we estimate that a non-adjuvanted vaccination program should have started 8 weeks earlier to lower the clinical attack rate by 50%. In conclusion, vaccination timing was a critical factor in relation to the spread of the 2009 A(H1N1) influenza. Our results also corroborate the central role of children for the transmission of A(H1N1) pandemic influenza.

Cost-effectiveness analysis of human papillomavirus-vaccination programs to prevent cervical cancer in Austria.

OBJECTIVE: The study predicts long-term cervical cancer related population health and economic effects of introducing the HPV-vaccination for 12-year-old girls (and boys) in addition to current screening compared with screening only. METHOD: Health effects are predicted by a dynamic transmission model. Model results are used to calculate incremental cost-effectiveness ratios (ICER) in euro per life year gained (LYG) for a time-horizon between 2008 and 2060 from a public payer and a societal perspective. RESULTS: Vaccination of girls results a discounted ICER of euro 64,000/LYG and euro 50,000/LYG from a payer's and societal perspectives respectively. The additional vaccination of boys increases the ICER to euro 311,000 and euro 299,000/LYG respectively. Results were most sensitive to vaccination price, discount rate and time-horizon. CONCLUSION: HPV-vaccination for girls should be cost-effective when adopting a longer time-horizon and a societal perspective. Applying a shorter time frame and a payer's perspective or vaccinating boys may not be cost-effective without reducing the vaccine price.