New Value
Study shows 70% drop in flu deaths
Thursday, February 7, 2008
Dr Sue Huang, ESR’s senior influenza scientist and head of the World Health Organisation (WHO) Influenza Centre, said ESR looked at national influenza surveillance data collected from 1997 to 2006. The data included community disease burden, circulating virus strains, hospitalisations, mortality and immunisation coverage. This was compared with the previous ten-year period.
"We found that influenza-related death has reduced by over 70% since 1997 when the vaccination policy changed, resulting in a steady increase of vaccine uptake. There was a decrease of influenza mortality in the over 65 year age groups which correlated well with a substantial increase of influenza vaccine uptake.
However, this group still has the highest mortality rates compared to other age groups (0-64 years). Therefore, vaccine uptake still needs to be increased in this age group, she said.
Dr Huang said the increasing trend of influenza hospitalisations required further analysis to understand whether it was due to improvements in coding, improvements in sensitivity of diagnostic tests, possible access problems to primary health care, changes in hospital admission criteria, demographics, or a true rise in influenza like illness.
“Hospital surveillance indicates that children and young people 0-19 have had a significant increase of average hospitalisation rates compared to the previous ten years. High rates of hospital admissions among young children have also been reported in the USA.
“We need to explore new measures to prevent influenza related hospitalisation among young people,” she said.
• Influenza A(H3N2) predominated for six seasons - (1998,99,2002,03,04,06) The A/Wisconsin/67/2005 (H3N2) like strain predominated in 2006 with the highest recorded hospitalisations.
• Influenza A(H1N1) predominated in 2000 and 2001
• Influenza B predominated in 1997 and 2005. 200 5 also saw the third highest recorded hospitalistions, particularly in children aged 5-19 when the B/Hong Kong/330/2001 like strain was around.
