More info sought on Mainland avian flu cases

[HenryN]

<TABLE cellSpacing=0 cellPadding=0 width=430 align=left border=0><TBODY><TR><TD class=theme_news_header>More info sought on Mainland avian flu cases </TD></TR><TR><TD>

</TD></TR><TR><TD class=theme_text vAlign=top align=left>Secretary for Food & Health Dr York Chow says the Government is concerned about the three recent human cases of H5N1 on the Mainland and has asked authorities for epidemiological study results when they are ready.

Speaking to reporters today Dr Chow said there are two main areas he is concerned about.

"One is if there is no avian flu outbreak in poultry and yet there are human cases, whether there is a change in the virus. Secondly, whether there are more so called 'silently infected chickens' that actually have the potential of carrying the virus and transmitting the disease and yet do not show any symptoms of illness or do not actually die from those illnesses.

"Because of that we have decided we will not increase the number of imported chickens from the Mainland this year so we will not change the pattern of trading and transport during this period."

Noting public concern about the rise in chicken prices Dr Chow said the decision not to increase live chicken imports during the festive period is appropriate.

He said the Government will be vigilant in combating smuggling, adding the public should be careful when they are approached by anyone selling chickens of unknown source.

http://www.news.gov.hk/en/category/healthandcommunity/090119/html/090119en05003.htm

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[mixin]

Re: More info sought on Mainland avian flu cases

Secondly, whether there are more so called 'silently infected chickens' that actually have the potential of carrying the virus and transmitting the disease and yet do not show any symptoms of illness or do not actually die from those illnesses.

I've often seen OIE reports showing only part of a flock as being infected, even thought there appears to be enough time to have passed for the entire flock to be infected. I've wondered if they're immune or asymptomatic and what would happen if they were not culled.

 

[HenryN]

Re: More info sought on Mainland avian flu cases

I've often seen OIE reports showing only part of a flock as being infected, even thought there appears to be enough time to have passed for the entire flock to be infected. I've wondered if they're immune or asymptomatic and what would happen if they were not culled.

They will shed virus and infected non-immunized hosts, like humans.

 

[mixin]

Re: More info sought on Mainland avian flu cases

So you think the ones appearing healthy are also carrying the virus. I wonder if the free roaming chickens tend stay away from the sick ones.

Do they often/sometimes/never test the live chickens?

 

[HenryN]

Re: More info sought on Mainland avian flu cases

So you think the ones appearing healthy are also carrying the virus. I wonder if the free roaming chickens tend stay away from the sick ones.

Do they often/sometimes/never test the live chickens?

Uusally live chickens are initially positive for antibodies (which is followed by detection of virus, which is usually at low levels).

 

[HenryN]

Re: More info sought on Mainland avian flu cases

China moves to prevent bird flu pandemic

The Chinese authorities are scrambling to prevent an outbreak of bird flu after three reported cases in the last two weeks.



By Malcolm Moore in Shanghai
Last Updated: 12:08PM GMT 19 Jan 2009

There is a potentially greater risk of exposure to sick birds as people shop in markets and handle poultry for teh New Year celebrations Photo: AP


Hundreds of millions of Chinese are preparing to travel home during Chinese New Year this weekend, and the authorities are concerned that the world's biggest human migration could help spread the disease further.
After not reporting a single human death from bird flu since 2003, the last two weeks have seen three cases in three separate provinces. The Agriculture Ministry said it was moving quickly to quarantine anyone who came into contact with the victims.
"As the Spring Festival approaches, there are frequent movements of poultry products and the risk rises of virus outbreaks and transmission," the ministry said in a statement. "We have already asked the relevant provinces to strengthen their bird flu prevention work," it added.
The first victim was a 19-year-old woman, Huang Yanqing, who lived in Beijing. She became ill with the H2N1 virus in December after eating a contaminated duck that was traced to Jinxian County in Tianjin, in North China.
After Miss Huang died on January 5 the Chinese authorities quarantined 200 people who had come into contact with her. They were all subsequently cleared.
Beijing's health authorities also said it had monitored all migrant workers and high-risk groups involved in poultry farming for possible signs of contamination.
Over the weekend, reports on Xinhua, the state news agency, confirmed that a 27-year-old woman from Jinan in Shandong Province died from the H5N1 virus on January 17. The woman was only named as Ms Zhang.
In addition, a two-year-old girl, named only as Miss Peng, fell ill on January 7 in Hunan province and is being treated in hospital. The local health authority did not explain how she had contracted the disease.
More than 180 million Chinese will travel home on the rail network for Chinese New Year, with several million more flying. Dishes prepared from freshly slaughtered chicken and duck feature prominently in celebration feasts. This means a potentially greater risk of exposure to sick birds as people shop in markets and handle poultry or when the birds are transported to be sold, the World Health Organisation said.
Health Ministry spokesman Mao Qun'an said last week that the public should minimise contact with poultry, especially sick or dead ones, and that medical institutions should step up surveillance of flu cases.
Since the H5N1 virus resurfaced in Asia in 2003, it has infected 391 people, killing 247 of them, according to WHO figures released in mid-December.
China has reported a total of 33 human bird flu cases, of whom 22 have died.
Thailand's Public Health ministry has also warned that 14 of the country's 76 provinces are at risk of bird flu while Nepal has also started testing flocks after discovering bird flu has entered the country.

http://www.telegraph.co.uk/news/wor...China-moves-to-prevent-bird-flu-pandemic.html

 

[mixin]

Re: More info sought on Mainland avian flu cases

These probably seem like very basic questions; but I've never given much thought to the difference in being immune or being asymptomatic.

Usually live chickens are initially positive for antibodies (which is followed by detection of virus, which is usually at low levels).

So after this point,
1. either the virus would be killed and the chickens would be immune and unable to further infect others. OR
2. the virus will co-exist with their immune system and they will be able to re-infect for how long? Months? Lifetimes?

Do the low levels at detction mean low levels of excretion and/or less ability to infect?

 

[HenryN]

Re: More info sought on Mainland avian flu cases

These probably seem like very basic questions; but I've never given much thought to the difference in being immune or being asymptomatic.



So after this point,
1. either the virus would be killed and the chickens would be immune and unable to further infect others. OR
2. the virus will co-exist with their immune system and they will be able to re-infect for how long? Months? Lifetimes?

Do the low levels at detction mean low levels of excretion and/or less ability to infect?

Level varies based on immunity in host and changes in virus.