Effect of increased influenza and pneumococcal vaccine coverage on the burden of influenza among elderly people in Hong Kong versus Brisbane: abridged secondary publication

1. Influenza and pneumococcal vaccine uptake in older adults of Hong Kong has dramatically increased since the SARS outbreak in 2003. This enables estimation of the effect of increased vaccine coverage by comparing the relative change in influenza disease burden with Brisbane, where vaccine coverage remained stable before and after 2003. 2. Compared with the low vaccination period (preSARS), during the first 6 years of high vaccination (post-SARS), influenza-associated excess rates of cardio-respiratory disease, stroke, and ischaemic heart diseases mortality decreased more in Hong Kong than in Brisbane. 3. After the 2009 H1N1 pandemic, excess rates of all-causes mortality increased in Hong Kong but to a lesser extent than in Brisbane. 4. This study provides limited evidence that markedly increased vaccination rates have reduced influenza disease burden in elderly people of Hong Kong.