Wednesday, April 20, 2005

Better than even is bad

In a move that belies some optimistic rhetoric from Vietnam, the ban on poultry farming previously covering Ho Chi Minh City (formerly Saigon) is now being extended to 15 cities and provinces (including Hanoi), in an effort to stem the stubborn tide of avian influenza (via The Australian). Small live poultry markets will be replaced by large slaughterhouses with a complete ban on free-range breeding of waterfowl. Beginning in August the government will pay for compulsory vaccination of poultry in high risk areas. Despite strict regulations, enforcement is inconsistent and spotty, with reports of live poultry roaming freely in areas of Ho Chi Minh City despite the ban (Bloomberg).

While Vietnam now claims all but one of the 35 afflicted provinces and cities (of 64 total) are clear of the disease, human cases continue to occur. The recent announcement of three more cases, including a double infection of H5N1 and HIV, underscored the problem (via CIDRAP). The explanation would thus seem to be either that the reports of eradication among poultry are incorrect (which is almost certainly the case) or that the disease has another reservoir, possibly human. Moreover experts on the scene are now intimating that the situation is changing:
Peter Horby, the WHO medical epidemiologist in Hanoi, said that while the mortality rate from H5N1 infections was falling, the virus appeared to be adapting to human hosts, which was taken to be an indication that transmission between humans would become easier.

"The fact that it's been around for a year and we haven't seen a pandemic is no reason to be complacent," he said.

"I'm more concerned than I was a year ago." He estimated the probability of a pandemic at "more than 50 per cent".

Dr Klaus Stohr, the WHO global influenza programme chief, reported an increase in the number of cluster cases reported recently, with the biggest a family of five cases.

There have been seven cluster cases in Vietnam, all within single families, most recently in the northern province of Haiphong.

No relative has been proved to have passed the disease to another, but Dr Horby said: "The onset dates could be consistent with human to human transmission." (The Telegraph [UK; my emphasis])
"More than 50%." That's better than even. And that's bad.

Addendum: Reuters (via is reporting that a 20 year old Cambodian woman has been rushed to a hospital in Vietnam with suspected bird flu. The victim is from Kampot province, bordering Vietnam, where three other confirmed cases and one unconfirmed case have previously been reported. Relatives say chickens near her home had died of unknown causes but there is no other information on exposure. Thus bird flu continues to smolder in southeast Asia.

Update (4/20/05, 7:38 am EDST): icWales and other sources now report the young woman has died. Prior to this the unofficial tally (CIDRAP) in the latest outbreak (since mid-December 2004) at 19 deaths out of 44 cases. Whether this latest death will be entered in the tally will depend upon the outcome of tests for H5N1. It sounds as if this is the likely diagnosis, however.