No H3N2 flu vaccine available until April as Hong Kong death toll jumps to 81
As death toll climbs to 81, manufacturers say correct jab will only be available in April
PUBLISHED : Friday, 30 January, 2015, 11:50am
UPDATED : Saturday, 31 January, 2015, 9:42am
Emily Tsang and Elizabeth Cheung
Patients reporting fevers wait to be seen at a Hong Kong hospital.
A vaccine to protect against a deadly influenza strain which has now claimed 81 lives in Hong Kong will not be available until April - after the winter flu peak is expected to have died down.
It is likely to arrive too late to have any effect, according to an expert in the city, where the existing vaccine has failed to prove a match for this winter's dominant virus strain - a mutated variant of the H3N2 virus known as a Switzerland strain.
The news came as seven more flu patients died yesterday. On Thursday, 10 patients died, the highest daily death toll of this season's epidemic so far. The death toll of 81 from just this month compares to the 149 flu deaths from all of last year.
Between January 2 and yesterday, 143 people, including children, had been admitted to intensive care units with severe flu. All the deaths were adults.
Food and Health Secretary Dr Ko Wing-man said artificial lungs were being used to help the most seriously ill to breathe. "The Hospital Authority has 12 artificial lungs in five hospitals; two are in use. I will closely monitor the situation," he said.
French vaccine maker Sanofi Pasteur said the company was completing its vaccines for the southern hemisphere's upcoming flu season, which typically starts in May, and jabs for Hong Kong doctors would not be ready for another three months.
"By then, most people in the community are expected to carry antibodies against the flu strain," said Dr Leung Chi-chiu, a member of the Centre for Health Protection's scientific committee on infection control.
With the vaccine requiring a further two weeks to take effect after being injected, he believed the vaccine would be too late to be of much help.
A poster about flu vaccines is displayed at Queen Elizabeth Hospital in Jordan. Photo: David Wong
The start of the winter flu peak at the beginning of the month came about three weeks earlier than in previous years - and has hit harder than usual. The peak usually runs for 14 to 16 weeks so is likely to last into March.
Leung said the summer flu season was usually less severe and of a smaller magnitude than the winter peak, as the virus tended to be less active in hot weather.
"It is hard to predict whether there will be a flu season at all in the coming summer, let alone to foresee whether the same flu strain will still be active," Leung said.
The epidemic this winter has been fuelled by the World Health Organisation's incorrect prediction that a so-called Texas variant of influenza A subtype H3N2, along with a few more strains, would be dominant this northern hemisphere winter. Instead, the Switzerland variant turned out to be prevalent - meaning this year's vaccine had limited effect.
It took six months for manufacturers to produce a vaccine matching the WHO forecast - and by the time other virus strains began to emerge as the dominant variants, it was already too late to include them in the jab, Leung added.
"It is always difficult to make a perfect prediction on the pattern of viruses," he said.
"The experts can only observe the rising trend of these viruses in the regions and make a guess on whether or not they will become prevalent."
Meanwhile, a three-year-old boy with influenza A was admitted to the paediatric intensive care unit at Princess Margaret Hospital, Kwai Chung, on Thursday after showing severe flu symptoms. The boy was diagnosed with pneumonia and his condition was yesterday described as stable.
