The Canadian authorities have announced that a new strain of influenza A virus has been found in two pig farm workers in the Province of Saskatchewan but it is not a new strain of A(H1N1) pandemic swine flu.
In a press statement released yesterday, 7 July, the Public Health Agency of Canada (PHAC) said they were working closely with the health authority in the Province of Saskatchewan to “assess the public health risk from a new strain of influenza” that had been detected in two workers on a hog farm in the province.
An investigation by scientists at the National Microbiology Laboratory of the PHAC in Winnipeg, found that the new strain contains genes from human seasonal flu and swine flu viruses. However, it is not a new strain of the pandemic A(H1N1) flu virus that has killed more than 400 people worldwide and contains human, swine and avian flu genes.
Chief Public Health Officer of Canada, Dr David Butler, said:
“As required under the WHO’s International Health Regulations, Canada has notified the WHO about the detection of this novel influenza virus.”
Since the pandemic alert countries like Canada that have a large pig farming industry have increased animal and human flu surveillance.
The workers were only mildy ill and have since made a full recovery, while a third case is still being investigated, said the PHAC.
According to a Reuters news report, Dr Greg Douglas, chief veterinary officer for Saskatchewan, said that the new virus contained genes from a seasonal H1N1 human flu strain and a flu virus commonly found in pig herds called triple reassortant H3N2.
Health Minister Leona Aglukkaq told the press that the national authorities were working closely with the province of Saskatchewan to find out as much as possible about the new flu virus.
“Preliminary results indicate the risk to public health is low and that Canadians who have been vaccinated against the regular, seasonal flu should have some immunity to this new flu strain,” said the Health Minister.
Butler added that:
“The Government of Canada remains vigilant and we will continue to keep Canadians informed of any new developments.”
Government investigators have also tested some of the pigs on the farm where the infected workers worked, and found that some were infected with swine influenza A, which is not uncommon among pig herds on farms.
However, the PHAC said there was no evidence that the new strain found in the workers was present in the pigs.
Douglas added that the infected herd did not show unusually high signs of illness. He said pig herds often got the flu and it usually only affects them mildly.
He reminded the press that this was not a food safety issue but a human health issue and that “Saskatchewan pork continues to be safe”.
Investigations are continuing, with PHAC scientists working with Saskatchewan public heath officials to monitor workers on the affected farm and in the rest of the province’s pig industry.
The Canadian Food Inspection Agency (CFIA) is also advising on how best to keep an eye on the swine herds and carrying out diagnostic tests in support of the preliminary tests carried out at the national labs in Winnipeg.
Source: Public Health of Canada, Reuters.
Written by: Catharine Paddock, PhD