Hong Kong has found a new variant of the H3N2 seasonal influenza virus, the spokesman for the Centre for Health Protection (CHP) said on Wednesday, urging high-risk groups to get influenza vaccinations.
The new variant is direct descendent of the Brisbane strain which has been the prevalent circulating strain of H3N2 in the past year in Hong Kong,
CHP Controller Dr Thomas Tsang said.
However, it has some genetic changes distinguishing it from the old Brisbane strain.
Overseas health authorities, including those in Canada, Britain and Australia, have also found the new variant.
There is no evidence showing that the H3 variant circulating in Hong Kong is more severe and resistant to oseltamivir (Tamiflu).
No flu vaccine with the variant virus component has been manufactured in the world, Tsang said.
Although vaccines provided for the northern hemisphere may not be a direct match for the new variant, CHP still urge them to get flu jabs before the arrival of the peak of seasonal flu, especially for the high-risk groups of elderly and children.
Tsang said the vaccines may give some protection against the virus.
The vaccines will be widely available in Hong Kong in a month, according Tsang.
Tsang said they will be monitoring this virus very closely in Hong Kong to see if there is any abnormal pattern during the summer peak and beyond.
H3N2 accounts for 43% of flu viruses circulating in Hong Kong while H1N1 accounts for 49%, CHP said.
H3N2, first detected in Hong Kong, caused roughly 34,000 deaths in the United States during the 1968-69 season. H3N2 viruses still circulate today and those over the age of 65 were most likely to die.