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Audio and power point presentation can be found here... http://www.emergency.cdc.gov/coca/callinfo.asp
Here are some of what I thought were highlights from this audio conference...
seasonal influenza - approximately 36,000 deaths annually in US with greater than 90% over the age of 64, approximately 200,000 hospitalizations with children under 2 being equally involved as adults over 64
even at peak of influenza season, only 25-35% of specimens from people with symptoms of acute respiratory infection test positive for influenza - this is partly because of the non-specificity of the symptoms and partly because of less than optimal sensitivity of the rapid tests
vaccine effectiveness is difficult to evaluate for multiple reasons....
one is whether the definition being used is influenza like illness (fever, cough, sore throat) (this would measure lower vaccine effectiveness as some of these cases would not be influenza however this is a more easily measured factor than viral culture and is commonly used)
also vaccines may not prevent disease altogether but may limit severe outcomes by partial protection
By looking at the antigenic deteminants in the lab, last years vaccine was 69% effective against H1N1, 21% effective against H3N2 and 3% effective against type B.
However this does not perfectly translate into clinical effectiveness as there may be some cross reactivity..
An interim study of this years vaccine effectiveness showed a 44% overall effectiveness including 58% for H3N2 and 0% for B. This was done on Medically Attended Acute Respiratory Illnesses (MAARI) that were lab confirmed as influenza by RT-PCR.
New vaccine strategy for next year is to recommend vaccination of all children and young adults 6 months to 18 years.
This is thought to be useful for several reasons. -there is a high rate of infection among this age group including 71 deaths this season (53 had co-infections with bacteria including 23 cases of Staph aureus, 12 of which were methicillin resistant) - this may curtail the rate of community spread of the disease - approximately half of this population should already be being vaccinated due to a risk factor such as asthma or contact with a person at risk such as an elderly family member or sibling with chronic illness etc...
Here are some of what I thought were highlights from this audio conference...
seasonal influenza - approximately 36,000 deaths annually in US with greater than 90% over the age of 64, approximately 200,000 hospitalizations with children under 2 being equally involved as adults over 64
even at peak of influenza season, only 25-35% of specimens from people with symptoms of acute respiratory infection test positive for influenza - this is partly because of the non-specificity of the symptoms and partly because of less than optimal sensitivity of the rapid tests
vaccine effectiveness is difficult to evaluate for multiple reasons....
one is whether the definition being used is influenza like illness (fever, cough, sore throat) (this would measure lower vaccine effectiveness as some of these cases would not be influenza however this is a more easily measured factor than viral culture and is commonly used)
also vaccines may not prevent disease altogether but may limit severe outcomes by partial protection
By looking at the antigenic deteminants in the lab, last years vaccine was 69% effective against H1N1, 21% effective against H3N2 and 3% effective against type B.
However this does not perfectly translate into clinical effectiveness as there may be some cross reactivity..
An interim study of this years vaccine effectiveness showed a 44% overall effectiveness including 58% for H3N2 and 0% for B. This was done on Medically Attended Acute Respiratory Illnesses (MAARI) that were lab confirmed as influenza by RT-PCR.
New vaccine strategy for next year is to recommend vaccination of all children and young adults 6 months to 18 years.
This is thought to be useful for several reasons. -there is a high rate of infection among this age group including 71 deaths this season (53 had co-infections with bacteria including 23 cases of Staph aureus, 12 of which were methicillin resistant) - this may curtail the rate of community spread of the disease - approximately half of this population should already be being vaccinated due to a risk factor such as asthma or contact with a person at risk such as an elderly family member or sibling with chronic illness etc...
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