Friday, May 18, 2012

Hong Kong Swine Flu Virus Surveillance

 


 

# 6333

 

 

Every few months we get an update from Hong Kong’s swine surveillance program conducted by the University of Hong Kong. Twice a month they sample pigs arriving at Sheung Shui slaughterhouse for influenza viruses.

 

Several influenza viruses commonly circulate in swine (primarily H1N1, H1N2, H3N2), but what these researchers are looking for are signs of new, or novel strains.

 

Of 1,100 samples tested between February and April of this year, 8 were found to be reassortments of swine flu viruses with genetic material from the 2009 H1N1 virus.

 

This is a lower number than the last report (see Hong Kong Swine Influenza Surveillance) which detected a total of 27 reassortant viruses out of 1,500 samples.

 

Reassortment happens when two different influenza viruses co-infect the same host, swap genetic material, and produce a hybrid virus. 

 

image

 

This report today is from the Hong Kong Government.

 

FEHD releases results of regular influenza virus surveillance in pigs from February to April

Friday, May 18, 2012

The Centre for Food Safety (CFS) of the Food and Environmental Hygiene Department today (May 18) announced results of the regular influenza virus surveillance programme on pigs at the Sheung Shui Slaughterhouse conducted by the University of Hong Kong (HKU) for February to April this year.

 

Among some 1,100 samples tested, no human swine influenza virus (pandemic H1N1) was detected.

 

A total of eight samples were found to contain viruses that were essentially swine influenza viruses but had picked up some genes of the human swine influenza virus.

 

According to Professor J S M Peiris, the HKU expert in charge of the surveillance programme, such viruses are unlikely to pose any major human health risks or cause problems in food safety.

 

Under the programme, the CFS has been helping HKU researchers to collect blood and tracheal and nasal swabs from pigs at the Sheung Shui Slaughterhouse twice a month to monitor influenza virus activity in pigs.

 

"Starting from the next cycle (covering results for May to July), regular reports and relevant data of the surveillance programme will be uploaded to the CFS website (www.cfs.gov.hk) on a quarterly basis for public information. Results of the surveillance programme will be announced immediately if findings have significant impact on food safety and public health," a spokesman for the CFS said.

 

(Continue . . . )

 

 

While neither particularly alarming or surprising, these virus detections are ongoing evidence of the evolution of influenza viruses in swine populations.

 

Here in the United States we’ve been watching our own emergent swine flu virus - the H3N2v – which has infected at least 13 people across 6 states since late last summer. My most recent blog on that virus may be read at Eurosurveillance: Cross Reactive Antibodies to H3N2v In Norway.

 

 

For more on the potential threat posed by reassortant swine viruses, I would invite you revisit my 2010 essay called:

 

The (Swine) Influenza Reassortment Puzzle