Indonesia finds H5N1 infected but healthy chickens

Reuters Asia ^ | 05 Oct 2005 11:36:28 GMT | staff

[Perdogg]

HONG KONG, Oct 5 (Reuters) - Indonesian health authorities have found chickens which tested positive for the H5N1 bird flu virus but which appear to be healthy, a sign that the bug may become harder to detect, officials in Hong Kong and Jakarta said.

Some species of waterfowl, like ducks and geese, are natural hosts of the H5N1 and do not fall ill from it. But the virus has always been known to be virulent in chickens, which fall sick quickly and die within 24 hours of contracting it.

Hong Kong's Health Minister York Chow said authorities in Indonesia had found infected chickens which were asymptomatic of the virus.

"As the virus may have spread so widely (in Indonesia), chickens have now become hosts," Chow told reporters in Hong Kong on Wednesday. He did not give other details.

"We are worried that if there are infected chickens which don't show any symptoms, then if we are in close contact with them, the chances of humans getting infected will be higher."

Mathur Riady, director general of the poultry department at Indonesia's agriculture ministry, confirmed the report.

"... we have also learned that in the case of the virus in birds they can be affected but they won't die," he told Reuters in Jakarta. "They even show no clinical symptoms."

Leo Poon, a microbiologist at the Chinese University in Hong Kong, said the discovery of the H5N1 infected, but asymptomatic, chickens was bad news, but more information was needed.

There are many different strains of the H5N1. Many have low pathogenicity and are relatively harmless, and only some have proven to be deadly for birds and humans.

"We don't have all the information and they could have just found a low pathogenic strain of H5N1 in the chickens. Or this could be a highly pathogenic strain but which has adapted itself in chickens or turned less virulent," Poon said.

"But the more chickens are infected, the higher the chance of the virus spilling over to humans," he said.

Bird flu has killed more than 60 people in four Asian nations since late 2003 and has been found in birds in Russia and Europe.

Experts' greatest fear is that the H5N1, which has a documented mortality rate of about 50 percent, could set off a pandemic if it gains the ability to be passed easily among people.

In Indonesia, officials have said five people are believed to have died from the H5N1. The World Health Organisation puts the number of dead at three, based on Hong Kong tests, and says there is a fourth case of a boy who has the disease but is alive and in stable condition. (Additional reporting by Yoga Rusmana in JAKARTA)

[mmercier]

>> Some species of waterfowl, like ducks and geese, are natural hosts of the H5N1 and do not fall ill from it. But the virus has always been known to be virulent in chickens, which fall sick quickly and die within 24 hours of contracting it.

It sounds like HN51 is a highly mutative strain of a rather nasty virus.

If it continues to mutate this rapidly into an airborne disease that can be passed as quickly as influenza we are in for some tough years ahead.

[goodnesswins]

"Many have low pathogenicity and are relatively harmless, and only some have proven to be deadly for birds and humans."

Wouldn't the state of the hosts IMMUNE system have something to do with how much harm the virus does?

[TheLion]

"Wouldn't the state of the hosts IMMUNE system have something to do with how much harm the virus does?"No....the 1918 Swine Flu, which killed almost 20 million worldwide took old and young alike. This one has some similar characteristics.

[billorites]

Infected, but healthy...

[meanie monster]

this is scary

[mmercier]

Just found this via Drudge: http://news.ft.com/cms/s/74ebe9d6-35cd-11da-903d-00000e2511c8.html