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**LMonty** · April 26, 2006, 05:43 PM

Re: UK: Chickens test for bird flu-strain (H7 or H5N1)

Even if it is H7, I'm wondering about the recombination possibilities. I wonder where it came from? Potentially, migratory birds? What other reservoir is there?

If so, I'm guessing htis goes to show that factory farms can and will probably get H5, and further shows the poultry industry refrain that they are safe is mostly wishful thinking...

hopefully Dr Niman will evaluate the news and share some info on what might happen if H5 and H7 get together.

**HenryN** · April 27, 2006, 01:02 AM

Re: UK: Chickens test for bird flu-strain (H7 or H5N1)

Commentary at

http://www.recombinomics.com/News/04270601/Bird_Flu_Great_Britain.html

**AlaskaDenise** · April 27, 2006, 01:52 AM

Re: UK: Chickens test for bird flu-strain (H7 or H5N1)

There's some very important information in here:
-------------------------------------------------
Bird Flu Detected on Great Britain Farm

Recombinomics Commentary
April 27, 2006

Chickens at a farm near Dereham in Norfolk are to be slaughtered after dead birds tested positive for a strain of bird flu.

Officials said preliminary test results indicated it was likely to be the H7 strain not the deadly H5N1 variation.

Last month a swan in Cellardyke, Fife, tested positive for the H5N1 strain

The above comments describe a bird flu outbreak in Great Britain. Although the infectious agent may be H7, co-circulation of H7 and the Qinghai strain of H5N1 is cause for concern.

Great Britain has reported one positive H5N1 case. However, results from test on over 7000 samples raise serious questions about the sensitivity of the surveillance testing. Bird flu is common in wild birds. Canada tested young ducks in August of 2005 and found H5 low pathogenic infections in many birds. 24% of the birds tested in British Columbia were H5 positive. The frequency of positives will vary by species, age and season, but over an extend time period 5-10% of birds tested should be positive for some form of bird flu. Testing in England only identified a few positive samples although over 7000 samples were tested. This low detection rate may be related to collection procedures which include storing collected swabs a 4 C, where they could dry out and reduce the detection or isolation of avian influenza.

The surveillance detected only one H5N1 positive bird and no birds positive for H7. The H7 or H5 infection of domestic poultry further suggests that the surveillance in England in particular, and Europe in general is inadequate. The only country to detect H5N1 in live wild birds has been Russia. H5N1 has been detected in dead birds in many European countries.

Co-circulation of H5 and H7 is cause for concern. In 2003 the Netherlands had an H7N7 outbreak, This strain was readily transmitted from birds to human and human to human. Over 80 cullers tested positive for H7 antibodies. However, a follow-up study found H7 antibodies in contacts of the cullers, indicating efficient human to human transmission. Most cases were mild with either no symptoms or mild flu symptoms. Most of the cullers also had conjunctivitis.

However a veterinarian developed pneumonia and died. The case is the only reported bird flu fatality by a serotype other than H5N1. The H7N7 isolated from the veterinarian had a number of unique polymorphisms, including PB2 E627K. E627K is universally found in H1, H2, and H3 isolates from humans. Prior to Qinghai Lake, all H5N1 isolates with E627K were from mammals. Many were from humans infected in Hong Kong in 1997 or Vietnam or Thailand in 2004. Most of these cases were fatal. E627K was also linked to virulence in experimental mice and increased polymerase activity at lower temperatures.

All 16 H5N1 isolates at Qinghai Lake had E627K. All reported PB2 sequences for Qinghai H5N1 isolates have also had E627K, including the buzzard isolate from Denmark this year. Dual infections involving H7 and H5N1 could allow the acquisition of E627K by H7. The acquisition could be driven by reassortment or recombination. H7 with E627K could be more virulent in humans and be easily transmitted between humans. The increased efficiency of human infections could also be acquired by H5N1 via recombination with the receptor binding domain on H7.

The H7 infection on a large poultry farm in England highlights the poor surveillance in England as well as the rest of Europe.

Countries reporting large numbers of negatives have serious surveillance issues, which are hazardous to the world?s health.
.

**AlaskaDenise** · April 27, 2006, 02:17 AM

Re: UK: Chickens test for bird flu-strain (H7 or H5N1)

To explain H7 well-honed RBS capability, see this referenced report.

Efficient Human to Human Transmission of H7N7 Bird Flu

Recombinomics Commentary
January 6, 2005

>>As at least 50 percent of the people exposed to infected poultry had H7 antibodies detectable with the modified assay, it was estimated that avian influenza A/H7N7 virus infection occurred in at least 1000, and perhaps as many as 2000 people. The seroprevalence of H7 antibodies in people without contact with infected poultry, but with close household contact to an infected poultry worker, was 59 percent. This suggests that the population at risk for avian influenza was not limited to those with direct contact to infected poultry, and that person-to-person transmission may have occurred on a large scale.<<

The report quote above indicates human to human transmission of H7N7 was quite efficient, with 59% of at risk individual testing positive for H7 antibodies, which were not detected in any of the control population, as reported earlier. Many of these contacts of infected poultry workers had mild or no symptoms.

These antibodies were detected in a modified assay that used equine red blood cells as targets instead of turkey red blood cells. The more efficient binding to the equine RBC is probably related to the observation that H7N7 virus has been isolated for infected horses since 1956, A/equine/Prague/1/56 (H7N7).

Thus, the ability for H7N7 to be efficiently passed from human to human may not be surprising. The vast majority of the patients in the Netherlands had conjunctivitis as a major symptom and there was only one reported death. Similarly, the two H7N3 infected poultry workers in Fraser Valley, British Columbia, or the two H7N2 infected cases in New York or Virginia also serological evidence of H7N2 infections.

The above instances of H7 infections would suggest that those with the most easily detected antibodies had mild cases (frequently with conjunctivitis) and only one fatality was reported, while those with lower levels (detected only with the modified test) were frequently asymptomatic.

Evidence for a similar population of people in Thailand or Vietnam infected with H5N1 but exhibiting mild or no symptoms is lacking. The recent study of patients in Thailand with respiratory disease failed to identify H5N1 positive patients with milder symptoms and a low case fatality rate. The group that had evidence of H5N1 infections had a case fatality rate of 67%, similar to the rate in officially confirmed cases on Thailand or Vietnam.

---------------------------------------------

Whoever thinks that influenza doesn't mutate to become more efficient in a host, needs to read how ever since 1956, H7 has been improving its mammalian adaptations.

**Mingus** · April 27, 2006, 07:48 AM

Re: UK: Chickens test for bird flu-strain (H7 or H5N1)

H7 cocirculate with H5N1 in other place too,

Do a rapid check of this old tread dating back from april 2.

H7 in Lebanon - FluTrackers News and Information

http://www.flutrackers.com/forum/showthread.php?t=3607&highlight=Lebanon

**Mingus** · April 27, 2006, 12:27 PM

Re: UK: Chickens test for bird flu-strain (H7 or H5N1)

Number of chicken culled...

http://uk.news.yahoo.com/27042006/325/chicken-cull-ordered-discovery-bird-flu-strain.html

Chicken cull ordered after discovery of bird flu strain Thursday April 27, 10:07 AM

LONDON (Reuters) - 35,000 chickens will be slaughtered after bird flu was found among dead birds on a farm in one of the country's biggest poultry farming areas, the government said on Wednesday.

A Department for Environment, Food and Rural Affairs (DEFRA) spokesman said the cull of all the birds on the farm in eastern England would take place as a precautionary measure.

"The preliminary test

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results show that it is likely to be the H7 strain of avian influenza and not H5N1," DEFRA said in a statement. The feared H5N1 strain has killed more than 100 people since late 2003, most of them in Asia.
The outbreak is on a farm near the market town of Dereham, in the eastern county of Norfolk, an agricultural centre which is home to some of Europe's biggest poultry farms.

An outbreak of the H7N7 bird flu strain in the Netherlands in 2003 led to the culling of 30 million birds, about a third of all Dutch poultry at a cost of hundreds of millions of euros.

A veterinarian working on an infected Dutch farm caught the disease and later died of pneumonia. It infected more than 80 people in total.

"Further tests are being carried out to determine the strain of the virus and more will be known tomorrow (Thursday)," the government said in a statement. "As a precautionary measure, birds on the premises will be slaughtered."

Earlier this month, the government confirmed its first case of H5N1 bird flu in a wild bird when a dead swan was found in eastern Scotland.

The swan was the only wild bird so far found in Britain to have the H5N1 virus, which has led to the death and culling of 200 million birds since around the world since late 2003.

Scientists fear bird flu could become highly dangerous to humans if the virus mutates into a form easily passed on from one person to another.

Both highly pathogenic and low pathogenic avian influenzas can infect humans but rarely do so. H5N1 is the bird flu strain which poses the biggest threat to public health, although cases of human infection remain relatively infrequent.

**LMonty** · April 27, 2006, 05:18 PM

Re: UK: Chickens test for bird flu-strain (H7 or H5N1)

Thank you Henry, for the comentary and link; and everyone else for your postings.

This almost sounds like an old theme- bad primers, no positives- for H7 it was wrong assays, no antibodies.

Could it be possible that our current H5 assays the wrong assays to determine mild infections?

**AlaskaDenise** · April 27, 2006, 05:22 PM

Re: UK: Chickens test for bird flu-strain (H7 or H5N1)

Monty:

I've been wondering the same thing about the primers. How can they keep up with the changes? Then throw in bad testing procedures - no wonder we see so many negatives.

.

**LMonty** · April 27, 2006, 05:30 PM

Re: UK: Chickens test for bird flu-strain (H7 or H5N1)

How can they keep up with the changes?

I admit total ignorance to how the primers are produced. But, if they require a strain close to that circulating, for manufacture; doesnt the practice of hiding sequences prior to publication mean that the primers are going to be less effective? If so, its not just general knowledge that the practice affects- it may actually be contributing to development of a pandemic by preventing effective seroprevalence studies.

Note I'm saying lots of "ifs" here, as I said, I'm ignorant of the process. I may be making a leap that isnt warranted. I'm just sharing a thought I had and wondering if someone more knowledgeable than I can shed light on it.

**AlaskaDenise** · April 27, 2006, 05:38 PM

Re: UK: Chickens test for bird flu-strain (H7 or H5N1)

Originally posted by LMonty

.........doesnt the practice of hiding sequences prior to publication mean that the primers are going to be less effective? If so, its not just general knowledge that the practice affects- it may actually be contributing to development of a pandemic by preventing effective seroprevalence studies............

VERY IMPORTANT POINT!!!

I don't know either - need to investigate, or perhaps our distinguished experts can fill in the gaps here.

.

**AlaskaDenise** · April 27, 2006, 08:17 PM

Re: UK: Chickens test for bird flu-strain (H7 or H5N1)

http://thescotsman.scotsman.com/uk.cfm?id=634412006

Fri 28 Apr 2006
Doctors check poultry farm staff in latest bird flu crisis

CAROL-ANN MACKENZIE
WORKERS at a poultry farm were being monitored by doctors last night as experts tried to trace the source of the latest bird flu outbreak to hit the UK.

Medics said there was no sign that anyone had become ill as a result of the virus in chickens at the farm in Norfolk.

But 35,000 chickens at Witford Lodge Farm, Hockering, were being slaughtered and incinerated as the Department for Environment, Food and Rural Affairs (DEFRA) tried to ensure the virus did not spread.
Vets said the virus at the farm, owned by Banham Poultry, was believed to be the H7 strain - not the H5N1 that has killed scores of people in Asia.

But Health Protection Agency officials said H7 could make people ill and had killed a vet in Holland three years ago. All precautions were being taken. The outbreak emerged only weeks after a wild swan, found dead in Cellardyke, Fife, tested positive for H5N1. The swan remains the only known UK case of H5N1.

Dr Sue Ibbotson, East Anglian director of the Health Protection Agency, said a dozen workers at the farm - plus staff involved in destroying the birds - were being monitored and offered anti-viral drugs.

"There is no need for panic," she said. "People living in the area should carry on with their lives as normal. They can still walk in the countryside. They can still eat poultry, providing it is properly cooked.

"There is a risk to the human population amongst those who are in very close contact with infected birds. The people most at risk in this case are poultry workers and people involved in the destruction of the birds.

"The people working at the farm are being monitored and have been offered anti-viral drugs. We are not aware of any reported illnesses."
Dr Ibbotson said people who became infected could suffer flu-like symptoms or eye irritations. Anyone living nearby who had been in contact with chickens from the site and was concerned should contact a doctor, she added.

Heather Peck, DEFRA's regional operations manager, said scientists were continuing to analyse samples taken from the birds. But she said all evidence pointed to the strain being H7 and there were no indications of it being H5N1.

DEFRA officials said the birds were being gassed or electrocuted and incinerated away from the farm.

Anthony Greenleaves, chief veterinary manager of the State Veterinary Service (SVS) in East Anglia, said birds at the farm had shown signs of illness a week ago and scores had died.

Daily death rates had then risen from around 15 to 80 and a vet had been called in. Tests then revealed avian flu and SVS officials had moved on to the farm on Wednesday.

He said Banham Poultry staff had acted properly and followed proper procedures. There was no reason to believe the virus would spread in the way the cattle disease foot and mouth might.

He hoped slaughtering the flock and disinfecting the site would prevent the virus from spreading.

DEFRA said compensation would be available to Banham Poultry.