H1N1
LONDON — The World Health Organization is recommending that swine flu be added to regular flu vaccines next season, The Associated Press reported Feb. 18.
The swine flu pandemic virus, or H1N1, emerged too late last year to be added to the regular flu vaccine, and a separate vaccine was needed.
For this year’s northern hemisphere flu season, however, the two vaccines should be combined, said Keiji Fukuda, the WHO’s flu expert.
The composition, announced after a four-day meeting of experts, means the H1N1 flu vaccine still held by drug-makers in bulk form may be used for part of the seasonal flu vaccine mix for 2010-11, Fukuda said.
"If they have the vaccine strain which is already made up and can be used, then they’re ahead of the game," Fukuda told Reuters after a public WHO session attended by drug companies.
But including protection against H1N1 in the usual vaccine doesn’t mean the pandemic has ended. The WHO expects it will remain a significant threat.
"The recommendation to put the [H1N1 flu] virus into the vaccine for the fall and winter is really a separate issue from whether the pandemic is over," Fukuda said.
Other experts agreed.
"I wouldn’t write the obituary for H1N1 just yet," said Michael Osterholm, a flu expert at the University of Minnesota. He said pandemic viruses in the past have caused waves of disease up to three years after the first outbreak.
In September, the WHO recommended the swine flu vaccine be included in the southern hemisphere’s next flu vaccine.
National health authorities would have to decide whether to combine the three strains into a single "trivalent" shot, offer three separate vaccines, or use a separate H1N1 shot and combine the other two in one shot," Fukuda said.
"For many countries, I think the answer is that a trivalent vaccine would make sense," he said.
The other recommended vaccine strains are H3N2 — which like H1N1 is a type of influenza A — and influenza B.
The WHO will convene a meeting of experts Feb. 23 to discuss whether the pandemic has peaked, Fukuda said. Such an announcement, however, would have little practical effect; countries such as the United States and Britain have already scaled back their swine flu response and cases have dropped sharply.
Osterholm said flu experts simply haven’t figured out how to define when a pandemic ends.
"If H1N1 comes back in a couple of months, is it a wave or is it just normal flu?" he asked. "There’s no scoreboard for us to check that."