Photo Credit – FAO
# 7152
Although infected poultry remains the number one suspect as the primary vector of the H7N9 virus in China, testing of birds has so far only turned up a small number of positive samples.
Adding to the mystery, overnight two media outlets (Reuters & Forbes) are both reporting that at least 40% of the human cases have `no clear history of poultry exposure’.
Two reports. First from Russell Flannery, senior editor and the Shanghai bureau chief of Forbes magazine:
40% Of Chinese Sick With H7N9 Bird Flu Had No Contact With Poultry – Report
Forty percent of China’s H7N9 bird flu cases involve individuals that have had no clear-cut contact with poultry, the Beijing News newspaper reported today.
Similarly, Reuters is reporting that Zeng Guang, chief epidemiologist at China’s Disease Prevention and Control Centre (CDPCC), is the source of the `40%’ quote.
He is also quoted as saying, “How did these people get infected? It’s a mystery.”
The Reuters report goes on to say:
According to a Reuters analysis of the infections, based on state media reports, only 10 out of the 77 victims as of Tuesday have had contact with poultry.
The CDPCC declined to comment when asked by Reuters.
You can read the entire Reuters report at:
China's bird flu death toll rises to 16, government warns of spread
BEIJING | Wed Apr 17, 2013 3:03am EDT
In this follow-up report, again from Reuters, WHO spokesperson Gregory Härtl is quoted as confirming that, "there are people who have no history of contact with poultry”.
WHO says no poultry contact in some China bird flu cases
GENEVA/BEIJING (Reuters) - The World Health Organization said on Wednesday that a number of people who have tested positive for a new strain of bird flu in China have had no history of contact with poultry, adding to the mystery about the virus that has killed 16 people to date.
As far as what to make of all of this - based on some `mammalian changes’ to the virus - there’s been speculation that another `intermediate host’ might be spreading the virus.
But credible evidence of such a host/vector has yet to be produced.
As far as the `no clear history of poultry exposure’ qualifier is concerned, it raises serious questions.
But as anyone who has taken a lot of medical histories can tell you - getting details like that accurately – particularly from sick patients or their distressed friends & relatives, can be challenging.
Trying to glean accurate epidemiological data from sparse media reports, even more so.
At this point – the primary source of infection remains infected poultry (with perhaps some limited human-to-human transmission among close family contacts).
But the possibility of another route of infection cannot be ignored, particularly at this early stage in the investigation.
All of which makes broader surveillance and testing of potential hosts a high priority.
An international team of experts, including members from the CDC and the World Health Organization, will soon be on the ground in China (see China: MOH Invites Outside Experts On H7N9).
Hopefully they’ll be able to provide a clearer picture of how this virus is transmitting in the days ahead.
