The Government confirmed a new H3N2 variant of influenza virus is endemic in Hong Kong

[Pathfinder]

The Government confirmed a new H3N2 variant of influenza virus is endemic in Hong Kong

Category: Mainland Medical

Nws Rank: 3

(Central News Agency Xinhua Wang Manna 29, Hong Kong)

The Hong Kong Government today confirmed that, in addition to a new outbreak of H1N1 influenza community-acquired infections, the new H3N2 pandemic influenza virus is in Hong Kong, and the constant mutation of the virus genome, so that Hong Kong faces two kinds of difficult at the same time the threat of influenza virus.

Hong Kong Department of Health Center for Health Protection Controller Dr Thomas Tsang, said at a press conference here today, H3N2 influenza virus originated from Brisbane virus emerged in Hong Kong this summer, in July began to grow between the infection and continued viral gene variant, Hong Kong is the seasonal influenza cases, 43% are H3N2 influenza virus, 49% belong to a new influenza virus H1N1, indicating that two kinds of tricky Hong Kong influenza virus has become the mainstream.

Dr Tsang said, H3N2 influenza virus variation of the common, not be ruled out because of ongoing viral gene mutations lead to more infected people in Hong Kong H3N2, he estimated that the peak period of infection is more likely to be extended in September to October this year, the authorities will be closely monitored.

University of Hong Kong Center for Infectious Diseases, director of infection and Ho Pak-leung said today that the production of influenza vaccine due to time-consuming, so the vaccine may be enough time to cope with the rate of mutation of the virus, although the new H1N1 variant of influenza vaccine for the H3N2 virus, produced only 30-40% lower disease effective role, but vaccination remains the most effective in preventing H3N2 method.

In addition, the Hong Kong Department of Health confirmed today that a further 189 new influenza H1N1 cases, patients involved 104 men and 85 women, aged between 7 months to 68 years old, which makes 3270 the total number of confirmed H1N1.


http://www.cna.com.tw/SearchNews/doDetail.aspx?id=200907290303

 

[AlaskaDenise]

Re: The Government confirmed a new H3N2 variant of influenza virus is endemic in Hong Kong

Does this match H3N2 A/Brisbane/10 in the 2009-2010 vaccine?

I'm not clear about what they're saying.

Mismatch H3N2 vaccine thread here:
http://www.flutrackers.com/forum/showthread.php?t=117451

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[Vibrant62]

Re: The Government confirmed a new H3N2 variant of influenza virus is endemic in Hong Kong

Is there a published gene sequence for the H3N2 variant? How big a genetic divergence are we talking about here?

The ferret co-infection study published yesterday suggested that pandemic H1N1 had selective advantage over seasonal H3N2. This data would suggest otherwise with this mutated strain as it is an almost equal split in prevalence - if the H3N2 variant is as infectious as pandemic H1N1 we are in for an interesting time.

 

[AlaskaDenise]

Re: The Government confirmed a new H3N2 variant of influenza virus is endemic in Hong Kong

The A/H3N2/HA Brisbane/10/2007 (vaccine source) is here:

ACI26318 566 Human HA H3N2 Australia 2007/02/06 Influenza A virus (A/Brisbane/10/2007(H3N2))
ABW23422 548 Human HA H3N2 Australia 2007/02/06 Influenza A virus (A/Brisbane/10/2007(H3N2))
ACD62305 333 Human HA H3N2 Australia 2007/02/06 Influenza A virus (A/Brisbane/10/2007(H3N2)) 1 F
ABW23424 550 Human HA H3N2 Australia 2007/02/06 Influenza A virus (A/Brisbane/10/2007(H3N2))
ABW23353 566 Human HA H3N2 Australia 2007/02/06 Influenza A virus (A/Brisbane/10/2007(H3N2))
ACD62335 336 Human HA H3N2 Australia 2007/08/11 Influenza A virus (A/Brisbane/602/2007(H3N2))

However, I'd assume the vaccine HA might have some virulence-reducing modifications.

But I don't see any new (2009) H3N2 Hong Kong H3N2 sequences. I'm looking at the NCBI database - maybe it's elsewhere.

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[AlaskaDenise]

Re: The Government confirmed a new H3N2 variant of influenza virus is endemic in Hong Kong

I did find 2 2009 Asian H3N2/HAs - 1 from Phillipines and another from Singapore. If that was Hong Kong has, they are clearly different than the Brisbane/10.

Looking at Singapore/39/2009/H3N2 HA, compared to Brisbane/10/2007/H3N2, I see (S=Singapore, P=Phillipines):

E78K - S+P

L86I - S

N160K - S+P

K174N - S+P

K189Q - S+P

N205K - S+P

I276M - S

R277Q - S

I377R - S+P

The above positions are the simple numbers in the NCBI database. I don't know about the offsets, so the position numbers may need adjusting. But the differences are there.

To summarize, in the HA - Singapore/39/2009 has 9/566 positions than differ from Brisbane/10/2007 concensus. I believe a small number of changes is normal, but at what number they become a problem, I'm not sure.

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[AlaskaDenise]

Re: The Government confirmed a new H3N2 variant of influenza virus is endemic in Hong Kong

The 2 2009 Asian H3N2/HA that I used are:

ACS71644 566 Human HA H3N2 Philippines 2009/03/05 Influenza A virus (A/Philippines/16/2009(H3N2))
ACS71648 566 Human HA H3N2 Singapore 2009/03/27 Influenza A virus (A/Singapore/39/2009(H3N2))

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[AlaskaDenise]

Re: The Government confirmed a new H3N2 variant of influenza virus is endemic in Hong Kong

Does anyone know if the changes listed in #5 are sufficient to say that the HK H3N2 has "escaped" the vaccine?

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