# 2754
It is a bit of a conundrum.
China has reported 8 human cases of H5N1 infection over the past month -and they attribute these infections to close contact with infected birds - but at the same time they deny any outbreaks of the virus among poultry.
Additionally, a small number of infected bird carcasses have washed up on the beaches of Lantau Island, near Hong Kong over the past week. Local officials suspect these birds were tossed into the Pearl River, which flows from Guangdong Province.
All of which is pretty strong evidence that the H5N1 virus is circulating, presumably in the domesticated bird population, in mainland China.
But according to China, they aren't seeing any sick or dying chickens.
If those reports are correct, it would suggest that some poultry may be carrying (and shedding) the H5N1 virus while remaining asymptomatic.
Whether due to a change in the virus, or perhaps partial immunity from a a failing vaccine, the prospect of so-called `silent' infections among domesticated poultry is not a particularly happy one.
HPAI (Highly Pathogenic Avian Influenza's) calling card, the way we spot it quickly, is by it's rapid onset of symptoms and high mortality rate in poultry.
Take that away, and farmers have no reason to suspect that any of their birds may be infected, and therefore take no steps to contain or eradicate it.
Of course, the only way to prove this is happening would be to test healthy looking birds for the virus.
Apparently that is being done, at least in some areas.
In December 2008, the H5N1 virus was supposedly detected in Jiangsu Province through routine testing, and 377,000 birds destroyed - yet according to state run media - no bird deaths or illness were attributed to the virus.
The ministry said it received information about H5N1 infection among hens in Dongtai and Hai'an on Monday. It was discovered during routine checks; no birds were reported sick.
This single instance (assuming the reporting is accuate) doesn't prove that the same situation is ongoing in other provinces, but it certainly suggests the possibility.
Whatever the explanation, all of this indicates that the bird flu situation in China, and likely in other countries as well, is becoming more complicated.
This report from China Daily.
No outbreak among poultry reported, says ministry
(China Daily)
Updated: 2009-02-06 07:33
There have been no reports of bird flu outbreak among poultry since January in the provinces where eight human infections were found, the Ministry of Agriculture (MOA) said Thursday.
"There is no epidemic outbreak of the H5N1 strain of avian influenza in the seven provinces where the human bird flu cases were identified," it said in a statement to China Daily.
The conclusion was arrived at based on research of the overall epidemiological situation and investigations conducted last month, the ministry said.
The statement was made in response to remarks by the UN's Food and Agriculture Organization (FAO) on possible bird flu outbreaks among poultry in China.
Eight human bird flu cases have been reported in the country in January, the most in a single month since 2003 when the lethal virus was first detected in humans, according to the World Health Organization (WHO). Five people have died.
"The human cases show the virus must be circulating among birds," Vincent Martin, a senior technical advisor on avian flu for the FAO, told Bloomberg.
He said the FAO had received no reports of bird flu cases among poultry from MOA since December.
"There must be some cases which have not been reported," Martin said. "It's not normal that we don't receive any confirmation or any reports of outbreaks in poultry."
Dr Hans Troedsson, WHO Representative in China, also expressed concern.
"The fact that this is the highest number (of human infections) for a single month in China reminds us that the virus is entrenched and circulating in the environment," he said.
The MOA said it has kept international organizations including the World Organization for Animal Health and the FAO updated about the bird flu situation in China.
Experts from the ministry said the existence of the bird flu virus does not necessarily mean an outbreak among poultry.
Of the 37 human cases reported in China since 2005, only 4 were linked to poultry outbreaks, the MOA said.
"It is quite common that not all human cases are interlinked with animal cases," the statement said.
The ministry also denied any bird flu cases in Guangdong province.
Three of 12 dead birds found on Hong Kong's Lantau Island tested positive for the strain, stoking concerns the virus is circulating widely among birds in southern Guangdong, which borders Hong Kong.
Shu Yuelong, director of the Chinese National Influenza Centre with the Ministry of Health, said human bird flu cases will continue to rise.
