Canadian Govt: Large Saskatchewan Chicken Farm - Highly pathogenic H7N3

[HenryN]

Re: Canadian Govt: Large Saskatchewan Chicken Farm - Highly pathogenic H7N3

Western Canada poultry farm quarantined <!-- END HEADLINE -->
<!-- BEGIN STORY BODY -->59 minutes ago


A poultry farm in Saskatchewan, in western Canada, was quarantined Thursday after avian flu was discovered on site, said the Canadian Food Inspection Agency.
"It may be difficult to identify the source of the virus, but the possibility of exposure to wild waterfowl -- which are the natural hosts for the virus -- cannot be discounted," the government agency said in a statement.
Tests showed chickens were infected with the H7N3 pathogen, which is not lethal to humans, on the farm about 100 kilometers (62 miles) north of Regina, the provincial capital.
This virus is not the same as the strain circulating in Asia, Africa and Europe, which has been associated with human illness.
"In this case, the affected birds were not destined for immediate slaughter and were not producing eggs for human consumption," the CFIA said.
Even so, all of the birds will be euthanized, the agency said, and to limit potential spreading of the virus a three-kilometer (1.9-mile) restricted zone has been set up around the farm.
In 2005, more than 60,000 ducks and other fowl were slaughtered in westernmost British Columbia province after another strain of avian flu was discovered on two local farms.
Previously, 17 million birds were slaughtered in the province in 2004 after an outbreak.

http://news.yahoo.com/s/afp/20070927/hl_afp/canadaanimalhealthbirdflu2_070927191835&printer=1;_ylt=AtPFgew55Q81dWMVT7wWmDWKOrgF

[HenryN]

Re: Canadian Govt: Large Saskatchewan Chicken Farm - Highly pathogenic H7N3

High-Pathogenic Bird Flu Found at Saskatchewan Farm (Update2)

By Jeff Wilson
<!-- WARNING: #foreach: $wnstory.ATTS: null at /bb/data/web/templates/webmacro_en/20670001.wm:105.2 --><!-- WARNING: #foreach: $wnstory.ATTS: null at /bb/data/web/templates/webmacro_en/20670001.wm:119.19 -->Sept. 27 (Bloomberg) -- A strain of bird flu that can be deadly to poultry, while posing little threat to humans, has been found at a chicken farm in Saskatchewan, the Canadian Food Inspection Agency said.
All 50,000 birds on the premises will be destroyed to prevent the infection from spreading, the agency said today in a statement. Officials stressed that the detected strain is different from the H5N1 virus that has killed at least 200 people and millions of birds in Asia, Africa and Europe.
``The most important thing to note at this time is that the domestic poultry industry is safe and free from the H5N1 which has been associated with human illness,'' Gerry Ritz, Canada's agriculture minister, said in a statement. The H7N3 strain that caused the Saskatchewan outbreak ``is unlikely to cause human sickness,'' he said.
Canada is trying to prevent an outbreak of bird flu like the one in British Columbia in 2004 that resulted in the destruction of 16 million chickens, turkeys, ducks and pigeons. Another outbreak of high-pathogenic avian influenza forced the slaughter of more than 60,000 ducks and other fowl in western British Columbia in 2005.
Quarantine
Measures imposed today include a 3-kilometer quarantine zone around the affected farm. The only poultry operation in a 10-kilometer (6-mile) radius will also be monitored for any signs of the illness, the CFIA said. The farm's birds were not destined for immediate slaughter and were not producing eggs for human consumption, it said.
The U.S. said it is barring all imports of live poultry and unprocessed poultry products from Saskatchewan. The action is in accord with an agreement between the two countries, John Clifford, the USDA's chief veterinarian, said in a statement. The U.S. has not imported poultry products from the province since 2005.
The source of the infection in Saskatchewan will be difficult to determine, officials said. The farm is in a rural area about 90 kilometers northwest of Regina. Wild waterfowl, which are natural hosts to the virus, are a possibility, the officials said.
Canada is expected to produce about 980,000 metric tons of chicken meat this year, or about 1.6 percent of world output, the USDA forecasts. In 2005, Saskatchewan accounted for about 3.3 percent of Canada's broiler meat production, according to data from the Agriculture and Agri-Food Canada Wet site.
To contact the reporter on this story: Jeff Wilson in Chicago at jwilson29@bloomberg.net .
Last Updated: September 27, 2007 16:02 EDT

http://www.bloomberg.com/apps/news?p...0&refer=canada#

[HenryN]

Re: Canadian Govt: Large Saskatchewan Chicken Farm - Highly pathogenic H7N3

Commentary at

http://www.recombinomics.com/News/09270701/H7N3_SK.html

[HenryN]

Re: Canadian Govt: Large Saskatchewan Chicken Farm - Highly pathogenic H7N3

Bird flu confirmed on Canadian chicken farm
27/09/2007 - 9:48:06 PM
A strain of bird flu that is not harmful to humans has been confirmed on a large chicken farm in Canada, officials said today.
The disease, found in Regina, Saskatchewan, is the H7N3 strain, the Canadian Food Inspection Agency said.
The same strain was behind a 2004 outbreak in British Columbia which saw 17 million chickens destroyed, but it is not dangerous to humans, said veterinarian Dr Sandra Stephens during a press conference in the city.
The farm in question, Pedigree Poultry at Regina Beach, breeds chickens which produce fertilised eggs for other farms. These eggs will be hatched at another facility, but Dr Stephens told reporters that the virus could not be carried by chicks born from those eggs.
None of the animals from the farm got into the food chain. Even if they had, the disease does not make the meat unsafe for humans, said Dr Stephens.
?It is important to remember that neither this nor any other AI (avian influenza) virus increases risk to food safety when properly handled.?

The chicken farm is about 40km (24 miles) north of Regina and has been quarantined since yesterday.
Dr Stephens emphasised that the CFIA is handling the outbreak in accordance with international standards.
All 50,000 birds on the farm will be destroyed using carbon dioxide gas and will be either composted or buried deep in the ground. Barns, tools, vehicles and equipment will be disinfected.
Dr Stephens said it is too early to pinpoint the source of the infection, although she suggested it may have been introduced by wild waterfowl such as ducks or geese.
Two people were infected in the 2004 outbreak, but they suffered only mild flu-like symptoms.
?We do recognise that there is potential with avian influenza viruses to have some capacity to produce illness in people,? Dr Stephens said. ?Normally those conditions would be very mild.?
Around the world, 200 people have died of bird flu since 2003, according to the World Health Organisation.

http://www.eecho.ie/news/bstory.asp?j=232809854&p=z3z8yx56x&n=232810614

[Laidback Al]

Re: Canadian Govt: Large Saskatchewan Chicken Farm - Highly pathogenic H7N3

. . . Two people were infected in the 2004 outbreak, but they suffered only mild flu-like symptoms.
?We do recognise that there is potential with avian influenza viruses to have some capacity to produce illness in people,? Dr Stephens said. ?Normally those conditions would be very mild.? . . .
http://www.eecho.ie/news/bstory.asp?...6x&n=232810614

Regarding the previous human cases from Canada in 2004.

Avian influenza A(H7) human infections in Canada
5 April 2004
The first human case of avian influenza A(H7) in British Columbia occurred in a person who was involved in culling of infected birds on 13-14 March. On 13 March, he may have been accidentally exposed in the eye. On 16 March, the individual reported conjunctivitis and nasal discharge. Treatment with oseltamavir, an antiviral drug active against influenza A viruses, began on 18 March. On 30 March, Health Canada concluded that this case was caused by avian influenza A(H7). Health Canada informed WHO of this case on 31 March. The patient's symptoms have fully resolved.
On 2 April, WHO was informed by Health Canada of a second poultry worker in British Columbia identified with avian influenza A(H7). This worker developed conjunctivitis in March 25 after close contact with infected birds. He was treated with oseltamivir on 25 March and his symptoms resolved.
Based on this epidemiological information provided by Health Canada, the World Health Organization today raised the global pandemic preparedness level from 0.1 to 0.2 for the Canadian outbreak.
Global pandemic preparedness levels are dictated by the epidemiological situation for each local event. Level 0.2 means that more than one human case caused by a new subtype of influenza virus has been identified in the local event.
In Asia, another avian influenza virus, A(H5N1), has been responsible for 34 reported human illnesses and 23 deaths. The existing global preparedness level of 0.2 for the avian influenza in Asia remains unchanged.
Preparedness levels have been organized into a matrix established by WHO in 1999(WHO Influenza Pandemic Preparedness plan). When a preparedness level is raised to 0.2, affected countries are advised to step up their surveillance in persons exposed to affected poultry, to organize special investigations to better understand the new virus, to advise persons at risk to wear protected clothing, and to consider the use of antivirals and normal human influenza vaccine.
WHO has been informed that Canada has taken all required actions in response to the current avian influenza A(H7) outbreak in British Columbia.
The new pandemic preparedness level for avian influenza A(H7) also means that WHO will begin a series of activities to obtain the virus, characterize it, and assess the needs for diagnostics and vaccine development.

http://www.who.int/csr/don/2004_04_05/en/

[HenryN]

Avian flu closes farm (H7N3)

Avian flu closes farm

Poultry operation north of Regina under quarantine


JOE FRIESEN
From Friday's Globe and Mail
September 28, 2007 at 6:04 AM EDT

<!-- dateline -->WINNIPEG<!-- /dateline --> ? A strain of avian influenza that led officials to order the killing of 17 million birds in British Columbia three years ago is tearing through a poultry farm in Saskatchewan.
The Canadian Food Inspection Agency said the chickens are infected with a highly pathogenic H7N3 form of the virus, which is deadly for poultry but unlikely to cause serious illness in humans.
The problem was first reported on Sunday, when an unusual number of chickens fell ill and died, but not publicly disclosed until yesterday when a laboratory was able to confirm the pathogen.
A three-kilometre perimeter has been established around the affected farm, located about 80 kilometres north of Regina, and any poultry operation within 10 kilometres will be closely monitored. All 50,000 chickens on the farm will be killed by carbon dioxide gas, the CFIA said, and the farm will remain under quarantine.
Sandra Stephens, a veterinarian with the CFIA, said at this point it's impossible to pinpoint the source of the outbreak, but said the virus may have been carried into the barn on clothes or equipment, or even by a wild bird.
The concern is that the virus may spread to other farms, as it did in B.C. in 2004, which would make a mass cull necessary. But the CFIA says that in Saskatchewan, unlike B.C., farms are quite distant from one another, making it harder for the virus to travel quickly.
The U.S. Department of Agriculture reacted yesterday by closing the border to poultry exports from Saskatchewan, not all of Canada, a move applauded by the Chicken Farmers of Canada.
The United States hasn't imported any poultry from Saskatchewan since 2005, and Chicken Farmers spokeswoman Lisa Bishop-Spencer said a regional ban is all that's warranted at this point. In any case, the Canadian poultry industry is geared primarily for domestic consumption, and exports make up only 7.5 per cent of sales, Ms. Bishop-Spencer said.
The affected farm is a broiler-breeder operation, which produces eggs that hatch broiler chicks, but Dr. Stephens said there's no chance of the virus entering the food chain because it kills any embryo it infects.
In British Columbia's Fraser Valley in 2004, two people developed conjunctivitis after coming in contact with infected birds, but their symptoms were not serious.
Todd Hatchette, director of virology at Queen Elizabeth II Health Sciences Centre in Halifax, said the H7 version of avian flu can infect humans but is much milder than the H5 version.
"This virus is really a problem for agriculture," Dr. Hatchette said.
The farm is expected to stay under a quarantine for at least 21 days after it has been cleaned and disinfected. Infected materials are then disposed of either through composting or by being buried.

http://www.theglobeandmail.com/servlet/story/RTGAM.20070928.wquarantine28/BNStory/National/home

[HenryN]

Re: Canadian Govt: Large Saskatchewan Chicken Farm - Highly pathogenic H7N3

Although official reports tend to make distinction between various H7 outbreaks (H7N3 in Canada H7N3 in 2004 and 2007, H7N3 and H7N2 UK in 2006 and 2007, H7N7 in the Netherlands in 2003), all resulted in human cases and all are H7,

[Gert van der Hoek]

Re: Canadian Govt: Large Saskatchewan Chicken Farm - Highly pathogenic H7N3

OIE report, outbreak started september 23:

http://www.oie.int/wahid-prod/public.php?page=single_report&pop=1&reportid=6260

Chicken broiler breeder flock. The operation consists of ten barns. There are 1100 roosters housed within two barns. In close proximity are three barns which house a total of 16,000, 10 week-old broiler breeder pullets.

Approximately 400 metres away are four laying barns which house a total of 16,000, 52 week-old broiler breeders and 16,000, 29 week-old broiler breeders. Approximately 540 roosters have died in one barn containing approximately 600 birds (approximately 90&#37; mortality). There are currently less than sixty birds remaining in this barn.

The 100 rooster had been moved from the affected barn into the 52 week-old breeder flock two weeks previously. Additionally, 160 rooster were moved to the 29 week-old breeder flock on September 17. No signs of illness have been noticed in any of the breeder barns; however, the 29 week-old breeder flock has not performed well; they did not peck as expected and production is not as good as anticipated.
On September 25, ancillary genetic results indicated the presence of an H7N3 virus in swab and tissue samples taken from the rooster barn. As of September 26, further test results indicate that birds in that barn were exposed to the virus several days prior to the findings as serology titers are demonstrated towards the virus.

H7N3 active infection was further demonstrated with the presence of live virus in tissues from dead birds and swabs. Initial virus molecular pathotyping indicate that the virus has a high pathogenic molecular pattern. All samples tested to date from birds located in the other barns on the same premise do not indicate the presence of avian influenza viruses.

Canadian Food Inspection Agency (CFIA) officials continue to proceed with the investigation according to the Notifiable Avian Influenza - Hazard Specific Plan (NAI-HSP).

CFIA will apply restrictions on the movement of poultry and poultry products
within three kilometres of the infected premises. As an additional safeguard, any poultry operations within ten kilometres of the infected premises will be closely and regularly monitored for signs of illness.

[HenryN]

Re: Avian flu closes farm (H7N3)

Information received on 28/09/2007 from Dr Brian Evans, Chief Veterinary Officer, 59 Camelot Drive, Room 146 W, Canadian Food Inspection Agency, OTTAWA, Canada
Summary
<TABLE class=rep_table cellPadding=0 width="100%" border=0 cellmargin="0"><TBODY><TR><TD class=rep_item width=200>Report type</TD><TD class=rep_data width=*>Immediate notification</TD></TR><TR><TD class=rep_item width=200>Start date</TD><TD class=rep_data width=*>23/09/2007</TD></TR><TR><TD class=rep_item width=200>Date of confirmation of event</TD><TD class=rep_data width=*>27/09/2007</TD></TR><TR><TD class=rep_item width=200>Report date</TD><TD class=rep_data width=*>28/09/2007</TD></TR><TR><TD class=rep_item width=200>Date submitted to OIE</TD><TD class=rep_data width=*>28/09/2007</TD></TR><TR><TD class=rep_item width=200>Reason for notification</TD><TD class=rep_data width=*>Reoccurrence of a listed disease</TD></TR><TR><TD class=rep_item width=200>Date of previous occurrence</TD><TD class=rep_data width=*>2004</TD></TR><TR><TD class=rep_item width=200>Manifestation of disease</TD><TD class=rep_data width=*>Clinical disease</TD></TR><TR><TD class=rep_item width=200>Causal agent</TD><TD class=rep_data width=*>Avian influenza virus</TD></TR><TR><TD class=rep_item width=200>Serotype</TD><TD class=rep_data width=*>H7N3</TD></TR><TR><TD class=rep_item width=200>Nature of diagnosis</TD><TD class=rep_data width=*>Clinical, Laboratory (basic), Laboratory (advanced)</TD></TR><TR><TD class=rep_item width=200>Report pertains to</TD><TD class=rep_data width=*>Entire country</TD></TR></TBODY></TABLE>

New outbreaks <TABLE class=rep_table width="100%" border=0><TBODY><TR><TD class=rep_item_ob width=200>Outbreak 1 (CAN-AI-2007-01)</TD><TD class=rep_data_ob width=*>Regina Beach, Regina, SASKATCHEWAN</TD></TR><TR><TD class=rep_item width=200>Date of start of outbreak</TD><TD class=rep_data width=*>23/09/2007</TD></TR><TR><TD class=rep_item width=200>Outbreak status</TD><TD class=rep_data width=*>Continuing (or date resolved not submitted)</TD></TR><TR><TD class=rep_item width=200>Epidemiological unit</TD><TD class=rep_data width=*>Farm</TD></TR><TR><TD class=rep_item width=200>Affected animals</TD><TD><TABLE class=rep_sub_table width="100%" border=0><TBODY><TR><TD class=rep_sub_item width="20%">Species</TD><TD class=rep_sub_item width="16%">Susceptible</TD><TD class=rep_sub_item width="16%">Cases</TD><TD class=rep_sub_item width="16%">Deaths</TD><TD class=rep_sub_item width="16%">Destroyed</TD><TD class=rep_sub_item width="16%">Slaughtered</TD></TR><TR vAlign=top><TD class=rep_sub_data>Birds</TD><TD class=rep_sub_data>49100</TD><TD class=rep_sub_data>560</TD><TD class=rep_sub_data>560</TD><TD class=rep_sub_data>0</TD><TD class=rep_sub_data>0</TD></TR></TBODY></TABLE></TD></TR><TR><TD class=rep_item width=200>Affected population</TD><TD class=rep_data width=*>Chicken broiler breeder flock. The operation consists of ten barns. There are 1100 roosters housed within two barns. In close proximity are three barns which house a total of 16,000, 10 week-old broiler breeder pullets. Approximately 400 metres away are four laying barns which house a total of 16,000, 52 week-old broiler breeders and 16,000, 29 week-old broiler breeders. Approximately 540 roosters have died in one barn containing approximately 600 birds (approximately 90% mortality). There are currently less than sixty birds remaining in this barn.</TD></TR><TR><TD class=rep_item_ob width=200>Summary of outbreaks</TD><TD class=rep_data_ob width=*>Total outbreaks: 1</TD></TR><TR><TD class=rep_item width=200>Outbreak statistics</TD><TD class=rep_data><TABLE class=rep_sub_table width="100%" border=0><TBODY><TR><TD class=rep_sub_item width="20%">Species</TD><TD class=rep_sub_item width="20%">Apparent morbidity rate</TD><TD class=rep_sub_item width="20%">Apparent mortality rate</TD><TD class=rep_sub_item width="20%">Apparent case fatality rate</TD><TD class=rep_sub_item width="20%">Proportion susceptible removed* </TD></TR><TR vAlign=top><TD class=rep_sub_data>Birds</TD><TD class=rep_sub_data>1.14%</TD><TD class=rep_sub_data>1.14%</TD><TD class=rep_sub_data>100.00%</TD><TD class=rep_sub_data>1.14%</TD></TR></TBODY></TABLE>* Removed from the susceptible population either through death, destruction or slaughter</TD></TR></TBODY></TABLE>
Epidemiology <TABLE class=rep_table width="100%" border=0><TBODY><TR><TD class=rep_item width=200>Source of infection</TD><TD class=rep_data width=*>

• <LI class=rep_list>Unknown or inconclusive
• Contact with wild species suspected but not confirmed

</TD></TR><TR><TD class=rep_item width=200>Epidemiological comments</TD><TD class=rep_data width=*>The 100 rooster had been moved from the affected barn into the 52 week-old breeder flock two weeks previously. Additionally, 160 rooster were moved to the 29 week-old breeder flock on September 17. No signs of illness have been noticed in any of the breeder barns; however, the 29 week-old breeder flock has not performed well; they did not peck as expected and production is not as good as anticipated.
On September 25, ancillary genetic results indicated the presence of an H7N3 virus in swab and tissue samples taken from the rooster barn. As of September 26, further test results indicate that birds in that barn were exposed to the virus several days prior to the findings as serology titers are demonstrated towards the virus. H7N3 active infection was further demonstrated with the presence of live virus in tissues from dead birds and swabs. Initial virus molecular pathotyping indicate that the virus has a high pathogenic molecular pattern. All samples tested to date from birds located in the other barns on the same premise do not indicate the presence of avian influenza viruses.
Canadian Food Inspection Agency (CFIA) officials continue to proceed with the investigation according to the Notifiable Avian Influenza - Hazard Specific Plan (NAI-HSP).
CFIA will apply restrictions on the movement of poultry and poultry products within three kilometres of the infected premises. As an additional safeguard, any poultry operations within ten kilometres of the infected premises will be closely and regularly monitored for signs of illness.</TD></TR></TBODY></TABLE>
Control measures <TABLE class=rep_table width="100%" border=0><TBODY><TR><TD class=rep_item width=200>Measures already applied</TD><TD class=rep_data width=*>

• <LI class=rep_list>Movement control inside the country <LI class=rep_list>Screening <LI class=rep_list>Quarantine <LI class=rep_list>Vaccination prohibited
• No treatment of affected animals

</TD></TR><TR><TD class=rep_item width=200>Measures to be applied</TD><TD class=rep_data width=*>

• <LI class=rep_list>Disinfection of infected premises/establishment(s)
• Stamping out

</TD></TR></TBODY></TABLE>
Diagnostic test results <TABLE class=rep_table width="100%" border=0><TBODY><TR><TD class=rep_item width=200>Laboratory name and type</TD><TD class=rep_data width=*>CFIA National Center Foreign Animal Disease, Winnipeg (National laboratory)</TD></TR><TR><TD class=rep_item width=200>Tests and results</TD><TD><TABLE class=rep_sub_table width="100%" border=0><TBODY><TR><TD class=rep_sub_item width="35%">Species</TD><TD class=rep_sub_item width="40%">Test</TD><TD class=rep_sub_item width="15%">Test date</TD><TD class=rep_sub_item width="10%">Result</TD></TR><TR vAlign=top><TD class=rep_sub_data>Birds</TD><TD class=rep_sub_data>competitive ELISA (c-ELISA)</TD><TD class=rep_sub_data>24/09/2007</TD><TD class=rep_sub_data>Positive</TD></TR><TR vAlign=top><TD class=rep_sub_data>Birds</TD><TD class=rep_sub_data>neuraminidase inhibition assay </TD><TD class=rep_sub_data>25/09/2007</TD><TD class=rep_sub_data>Positive</TD></TR><TR vAlign=top><TD class=rep_sub_data>Birds</TD><TD class=rep_sub_data>polymerase chain reaction (PCR)</TD><TD class=rep_sub_data>25/09/2007</TD><TD class=rep_sub_data>Positive</TD></TR><TR vAlign=top><TD class=rep_sub_data>Birds</TD><TD class=rep_sub_data>polymerase chain reaction (PCR)</TD><TD class=rep_sub_data>26/09/2007</TD><TD class=rep_sub_data>Positive</TD></TR></TBODY></TABLE></TD></TR><TR><TD class=rep_item width=200>Laboratory name and type</TD><TD class=rep_data width=*>CFIA NAtional Center Foreign Animal Disease, Winnipeg (National laboratory)</TD></TR><TR><TD class=rep_item width=200>Tests and results</TD><TD><TABLE class=rep_sub_table width="100%" border=0><TBODY><TR><TD class=rep_sub_item width="35%">Species</TD><TD class=rep_sub_item width="40%">Test</TD><TD class=rep_sub_item width="15%">Test date</TD><TD class=rep_sub_item width="10%">Result</TD></TR><TR vAlign=top><TD class=rep_sub_data>Birds</TD><TD class=rep_sub_data>haemagglutination inhibition test (HIT)</TD><TD class=rep_sub_data>26/09/2007</TD><TD class=rep_sub_data>Positive</TD></TR><TR vAlign=top><TD class=rep_sub_data>Birds</TD><TD class=rep_sub_data>virus isolation</TD><TD class=rep_sub_data>26/09/2007</TD><TD class=rep_sub_data>Positive</TD></TR><TR vAlign=top><TD class=rep_sub_data>Birds</TD><TD class=rep_sub_data>virus sequencing</TD><TD class=rep_sub_data>27/09/2007</TD><TD class=rep_sub_data>Positive</TD></TR></TBODY></TABLE></TD></TR></TBODY></TABLE>Map of outbreak locations

http://www.oie.int/wahid-prod/public.php?page=single_report&pop=1&reportid=6260

[Farmer]

Re: Avian flu closes farm (H7N3)

Post from ProMed today which indicates that eggs from the infected flock will be hatched out at another facility (see bolded section below). I am surprised, as I thought that the whole issue of vertical transmission had not been resolved. Most of the information I find states that virus HAS been isolated from eggs of infected birds, but that the virus is expected to 'most likely' kill the chicks before they hatch:


Date: Fri, 28 Sep 2007 10:07:30 -0400 (EDT)
From: ProMED-mail
Subject: PRO/AH/EDR> Avian influenza (163): Canada (SK), H7N3

AVIAN INFLUENZA (163): CANADA (SASKATCHEWAN), H7N3
**************************************************
A ProMED-mail post

ProMED-mail is a program of the
International Society for Infectious Diseases


Date: Thu 27 Sep 2007
Source: CBC News [edited]



Avian influenza has been confirmed at a large chicken farm near
Regina, officials with the Canadian Food Inspection Agency (CFIA)
said Thursday 27 Sep 2007].

The H7N3 strain of the virus found at Pedigree Poultry at Regina
Beach is fatal to birds, but is not dangerous to humans, the agency
said. All 50 000 birds at the farm will be destroyed with carbon
dioxide gas over the next few days.

"We could consider the entire premise to be infected," CFIA
veterinary specialist Sandra Stephens said. Speaking to reporters in
Regina, Stephens said the farm-produced eggs will be hatched at
another facility, but added that the virus couldn't be carried by
chicks born from those eggs.

Stephens said the H7H3 [this was from the original article and likely
a typo; it should be H7N3 - Mod.TG] subtype is not normally
associated with serious human illness. When asked whether any of the
people around the farm have been tested or were sick, Stephens said
that was a question for health officials.

Earlier in the day [27 Sep 2007], the road to the farm was blocked
off about a kilometer (0.6 mi) away, and an official in a car was
making sure nobody tried to get through. The official told a CBC
reporter anyone coming out would be disinfected.

Officials with the local rural municipality were issuing a warning to
the public. "I would advise people to just stay away from the area
because if there is a disease issue, we don't need to have any of
this spread about either in our area, or any other area," said Jim
Hipkins, reeve for the rural municipality of Lumsden.

Vehicles leaving the farm Wednesday [26 Sep 2007] were seen having
their tires washed. People walking in the area were also seen having
their footwear sprayed down.

Stephens said equipment and tools at the facility will be cleaned and
disinfected in the days ahead. A 3-km (2 mi) control zone has been
established around the farm, but the facility is the only one in the
zone with poultry, she said.

However, there is a Hutterite colony with a 65 000-bird chicken
operation about 8 kilometres (5 mi) away from the Pedigree Poultry
site. [Hutterites are a communal branch of Anabaptist Christians who
trace their roots to the Radical Reformation of the 16th century and
are now living in parts of Canada and the northwest United States. - CopyEd.MJ]

Nobody knows how the infection spread to the Regina Beach-area farm,
but the virus is commonly carried by migrating waterfowl, Stephens
said. Regina Beach is about 55 kilometres (34 mi) northwest of Regina.

Health authorities are concerned about avian flu because of the way
the virus can jump to other species, including humans. Some believe
avian flu could someday cause a worldwide pandemic.

Around the world, 200 people have died of avian flu since 2003,
according to the World Health Organization.

An outbreak of one strain of avian flu on a poultry operation in
British Columbia in 2004 saw 2 people infected, but they suffered
only mild flu-like symptoms.

However, the poultry industry took a major blow when the disease
forced the destruction of more than 17 million birds.

- --
Communicated by:
ProMED-mail Rapporteur Mary Marshall

[The outbreak of avian influenza in British Columbia in 2004 was
highly pathogenic strain H7N3. This article does not state if this is
a low or high pathogenic strain. Hopefully some testing is being done
on the strain even as they are depopulating the premises. - Mod.TG

Other articles have identified it as a highly pathogenic strain.- Mod.DK

The province of Saskatchewan can be located on the map at
.
- - CopyEd.MJ]

[see also:
2006
- ----
Avian Influenza (141) Canada (PE): not highly pathogenic 20060620.1706
Avian influenza (138) - Canada (PE) 20060616.1677
2005
- ----
Avian influenza - Canada (06) 20051211.3572
Avian influenza - Canada (05): comment 20051124.3409
Avian influenza - Canada (04): BC, MB 20051121.3379
Avian influenza, H5, poultry - Canada (BC) 20051120.3370
Avian influenza - Canada (02): survey wild ducks 20051102.3204
Avian influenza - Canada: survey wild ducks 20051031.3182
Avian influenza, imported pigeons - Australia (NSW) ex Canada 20051020.3062
Avian influenza, turkeys, H3 - Canada (BC) 20050601.1524
2004
- ----
Avian influenza - Canada (ON): susp 20040721.1992
Avian influenza, poultry - Canada (BC): H5 not 20040514.1311
Avian influenza, poultry - Canada (BC): H5 susp. 20040512.1281
Avian influenza - Canada (23): OIE 20040507.1248
Avian influenza, H7, poultry - Canada (BC) (22) 20040505.1233
Avian influenza, H7, poultry - Canada (BC) (21) 20040425.1144
Avian influenza, H7, poultry - Canada (BC) (20) 20040422.1116
Avian influenza, H7, poultry - Canada (BC) (19) 20040416.1052
Avian influenza, H7, poultry - Canada (BC) (18) 20040415.1029
Avian influenza, H7, poultry - Canada (BC) (17) 20040414.1014
Avian influenza, H7, poultry - Canada (BC) (16) 20040412.0994
Avian influenza, H7, poultry - Canada (BC) (15): OIE 20040410.0974
Avian influenza A (H7), human - Canada (BC) (04) 20040407.0948
Avian influenza, H7, poultry - Canada (BC) (14) 20040407.0946
Avian influenza A (H7) virus, human - Canada (BC) (03) 20040406.0935
Avian influenza, H7, poultry - Canada (BC) (13) 20040404.0925
Avian influenza A (H7N3) virus, human - Canada (BC) (02) 20040402.0908
Avian influenza, H7, poultry - Canada (BC) (12) 20040401.0893
Avian influenza, H7, poultry - Canada (BC) (11) 20040330.0870
Avian influenza, H7, poultry - Canada (BC) (10) 20040327.0843
Avian influenza A (H7N3) virus, human - Canada (BC) 20040327.0842
Avian influenza, H7, poultry - Canada (BC) (09) 20040324.0821
Avian influenza, H7, poultry - Canada (BC) (08) 20040323.0814
Avian influenza, H7, poultry - Canada (BC) (07): correction 20040315.0721
Avian influenza, H7, poultry - Canada (BC) (06) 20040313.0704
Avian influenza, H7, poultry - Canada (BC) (05): OIE 20040310.0675
Avian influenza, H7, poultry - Canada (BC) (04): RFI 20040310.0672
Avian influenza, H7, poultry - Canada (BC) (03): OIE 20040222.0562
Avian influenza, H7 serotype, poultry - Canada (BC) (02) 20040221.0557
Avian influenza, H7 serotype, poultry - Canada (BC) 20040220.0548]
...................................tg/mj/dk



Then I found this from the USDA's 'gray book' of foreign animal diseases (see paste below). Which makes me wonder why they would take the chance?

Any one else have anything more definitive information on vertical transmission of HPAI in poultry?

It is interesting that Lancet has just published an article documenting vertical transmission in an H5N1 infected human (http://www.thelancet.com/journals/la...5153/abstract).

AVIAN INFLUENZA (Fowl Plague)
C.W. Beard, D.V.M., USDA, ARS. Southeast Poultry Research Laboratory, Athens, GA.

http://www.vet.uga.edu/vpp/gray_book/FAD/avi.htm

Avian influenza has produced losses of variable severity, primarily in turkeys in the United States, since the mid-1960's. The disease outbreaks in turkeys in the United States have been caused by AI viruses with many of the HA designations. It was in the fall of 1983 that a highly virulent H5 virus produced severe clinical disease and high mortality in chickens, turkeys, and guinea fowl in Pennsylvania. This severe disease, clinically indistinguishable from classical fowl plague, occurred after a serologically identical but apparently mild virus had been circulating in poultry in the area for 6 months.


Outbreaks of less virulent AI have frequently been described in domestic ducks in many areas of the world. The AI viruses are often recovered from apparently healthy migratory waterfowl, shore birds, and sea birds worldwide. The epidemiologic significance of these isolations relative to outbreaks in domestic poultry has led to the generally accepted belief that waterfowl serve as the reservoir of influenza viruses.


Transmissions

There is a considerable body of circumstantial evidence to support the hypothesis that migratory waterfowl, sea birds, or shore birds are generally responsible for introducing the virus into poultry. Once introduced into a flock, the virus is spread from flock to flock by the usual methods involving the movement of infected birds, contaminated equipment, egg flats, feed trucks, and service crews, to mention a few. Preliminary trapping evidence indicates that garbage flies in the Pennsylvania outbreak were sources of virus on the premises of the diseased flocks. Virus may readily be isolated in large quantities from the feces and respiratory secretions of infected birds. It is logical to assume, therefore, that because virus is present in body secretions, transmission of the disease can take place through shared and contaminated drinking water. Airborne transmission may occur if birds are in close proximity and with appropriate air movement. Birds are readily infected via instillation of virus into the conjunctival sac, nares, or the trachea. Preliminary field and laboratory evidence indicates that virus can be recovered from the yolk and albumen of eggs laid by hens at the height of the disease. The possibility of vertical transmission is unresolved; however, it is unlikely infected embryos could survive and hatch. Attempts to hatch eggs in disease isolation cabinets from a broiler breeder flock at the height of disease failed to result in any AI-infected chickens. This does not mean that broken contaminated eggs could not be the source of virus to infect chicks after they hatch in the same incubator. The hatching of eggs from a diseased flock would likely be associated with considerable risk.

[HenryN]

Re: Avian flu closes farm (H7N3)

It would seem that vertical transmission of HPAI would be likely. The Lancet results were not surprising. HPAI AI has a polybasic cleavage site, which allows for virus replication in multiple tissue types because the polybasic cleavage site increases the number of proteases that can cleave HA. Consequently, the virus can spread to many tissue types outside of the respiratory tract.

Since the H7N3 in Canada is said to be high path based on sequence analysis, it would seem to have a polybasic cleavage site and therefore could spread vertically.

[Gert van der Hoek]

Re: Avian flu closes farm (H7N3)

@ Farmer:

Today I stumbled on a retrospective story about the bird flu outbreak in Bali. First confirmation of bird flu in Bali was in 2004, by a team of the University under supervision of Mahardika.

They did (in 2004) a test on 10 days old embryo in eggs; after injection of fluids of dead birds supposed to have H5N1, the embryo?s died in 20 hours:


In 2004 that then confirmation about the existence of the AI case in Bali happened.

The team of the researcher has from the Universitas Udayana School Of Veterinary Medicine isolated the virus of Avian Influenza (AI) to the nonpedigreed chicken in Bali.

The case that was found by the team of the expert this FKH Unud happened to the property nonpedigreed chicken of a breeder in the Kerobokan Village, Kota Madya Denpasar that on June 16 2004 that showed the sign did not want to eat and drink, the dull hair, weak, pale, inkoordinasi and the head bent xNP.

As for the team from FKH Unud was GNK Mahardika, M. Sibang, M. Suamba, KA Adnyana, NMS Dewi, KA Meidiyanti, and YES Paulus.

In the case that was reported the Veteriner FKH Universitas Udayana Journal, the carcass operation was found by the point bleeding or spread under skin, trakhea and the lungs, proventrikulus and wiped the tonsils.

Further, the material suspension of the lungs, wiped-tonsils, and silly the example diinjeksikan to space alantois the chicken egg sprouted the age 10 days.

Around 20 hours paska the injection all embryo died and experienced the bleeding of all the body as well as his membrane.

http://www.flutrackers.com/forum/showpost.php?p=102724&postcount=56

[Farmer]

Re: Avian flu closes farm (H7N3)

Thanks Dutchy. It makes sense that injecting live virus into developing eggs would kill them. My understanding is that this was one of the limiting factors to large scale H5N1 vaccine production, that the virus, even a modified live version, was so lethal to embryos.

It is unclear to me why the Canadian vet would OK a scheme to hatch out eggs from the farm. However, maybe I am reading too much into her comment. She actually is quoted as just saying that surviving chicks will not be carriers....

[Gert van der Hoek]

Re: Canadian Govt: Large Saskatchewan Chicken Farm - Highly pathogenic H7N3

2nd Saskatchewan farm under quarantine over avian flu worries

Last Updated: Saturday, September 29, 2007 |

The Canadian Food Inspection Agency (CFIA) has put another Saskatchewan chicken farm under quarantine, but says the move is only a precautionary measure.

The small farm affected by the decision on Friday is less than three kilometres away from Pedigree Poultry, a much larger operation just north of Regina, where officials confirmed on Thursday they had found a strain of avian influenza.

The CFIA said the quarantine measures are standard given the close proximity of the two farms. It said the 20 chickens tested on what the agency calls a "small backyard operation" have shown no signs of disease.

More than 50,000 chickens at the Pedigree Poultry operation near Regina Beach were to be killed and all equipment thoroughly sanitized.

The H7N3 strain of influenza is fatal to birds, but isn't a danger to human health, and it's not expected to have much of an economic impact, according to Lisa Bishop Spencer of the Chicken Farmers of Canada.

She says much has changed since Canada had its last case of avian flu three years ago in British Columbia, where the virus swept through a number of farms, and that industry and government have developed a system to respond quickly to any future outbreaks.

http://www.cbc.ca/canada/saskatchewan/story/2007/09/29/avian-flu.html

[HenryN]

Re: Canadian Govt: Large Saskatchewan Chicken Farm - Highly pathogenic H7N3

September 29, 2007

• The <ACRONYM title="Canadian Food Inspection Agency">CFIA</ACRONYM> began humane depopulation of birds on the affected farm on September 28.
• Medical staff and regional animal welfare representatives will be on site throughout the disease control operations.
• All birds will be disposed of in accordance with provincial environmental regulations and internationally accepted disease control and biocontainment guidelines.
• As a precaution, one backyard flock located in the three-kilometre region around the index farm has also been placed under quarantine measures. This is not a commercial operation. There have no signs of illness in the flock and test results from samples taken from this flock will determine next steps.
• Surveillance of premises within the three-kilometre and 10-kilometre regions around the index farm is underway.
• Although there has been limited movement on or off the index farm, the <ACRONYM title="Canadian Food Inspection Agency">CFIA</ACRONYM> is conducting a comprehensive trace-out investigation associated with all recent movement of birds, bird products, vehicles or equipment.
• Avian influenza viruses do not pose risks to food safety when poultry and poultry products are properly handled and cooked.
• The <ACRONYM title="Canadian Food Inspection Agency">CFIA</ACRONYM>'s actions are consistent with internationally recognized animal health guidelines and the CFIA?s established avian influenza response protocols.
• The <ACRONYM title="Canadian Food Inspection Agency">CFIA</ACRONYM> is collaborating with the Province of Saskatchewan, industry, local authorities, health officials and the producer in this response effort.

http://www.inspection.gc.ca/english/...tuatione.shtml