February 11 Flu UpdateA 20 year old woman died of bird flu in Indonesia. (reported yesterday). In addition, two of her neighbors are in the hospital.
ProMed on Indonesia.
The four cases in Turkey were negative...
as did the six potential cases in Egypt.
There could be criminal charges in the bird flu importation case in Britain.
There's another avian outbreak in South Korea.
Promed sweeps the world....nothing not already reported here.
Editorial in Southern Mississippi follows up on article series this week by comparing pandemic to something familiar---a hurricane.
USDA wants Chinese chicken imported again into the US.
ProMed on the story that we ran yesterday that wondered if people born before 1969 might not have some immunity to H5N1. Note the mod comment:
If an element of immunity to avian influenza A (H5N1) does exist in older populations, its possible association with geographically widespread (intercontinental) influenza A events before the late 1960s merits further investigation."
Finally, Revere weighs in on this story. What is the explanation for this phenomenon? He doesn't seem to be buying the immunity theory...this is a little dense, but it argues that H5N1 is less noticeable in older people, and therefore less likely to be reported. In other words, the age difference is not real....or as stark as it appears. Blog post is a must read. (My note: this story is one to watch. It could be used to generate a false comfort zone, or to discourage further prep.)
Yet another possibility (and one we favor) is that the unusualness of the disease is less obvious in older individuals for reasons unrelated to prior exposure but possibly related to different immunological or other biological responses to infection (e.g., cross reactivity with other infections). Serious and rapidly evolving respiratory disease in a young and healthy person attracts considerably more attention than in the elderly.This could result in reduced ascertainment of respiratory disease against a background of high prevalence from the usual circulating respiratory viruses in the older age groups. Diagnosis of H5N1 infection depends critically on index of suspicion, a threshold likely met in only a small proportion of influenza-like illnesses which might be H5N1 and less so among older patients than younger. If the disease in the over 40 age group is also somewhat less severe, this could impart an ascertainment bias and the question of whether the cases match the age structure of the population would again be something to consider.