The World Health Organisation said Thursday that the swine flu pandemic virus would threaten again next winter in the northern hemisphere and recommended its inclusion in the regular influenza vaccine.
Protection for two other seasonal strains should be incorporated along with the A(H1N1) pandemic strain that swept across the world last year, the UN health agency said after the biannual meeting of flu vaccine experts.
"It is expected that A(H1N1) pandemic 2009, A(H3N2) and B viruses will co- circulate in the northern hemisphere 2010-2011 with the likelihood that the pandemic A(H1N1) 2009 viruses will predominate, the WHO said in a report.
The UN health agency had already made a similar recommendation last September for the southern hemisphere seasonal flu vaccine for 2010.
Experts establish the cocktail for seasonal flu vaccines twice a year for the northern and southern hemispheres, about eight months ahead of the onset of their cold seasons.
Health authorities and pharmaceutical companies rushed through a separate vaccine for A(H1N1) after the new swine flu strain was uncovered in Mexico and the United States last April, prompting the WHO to declare a pandemic as the virus spread swiftly into more than 200 countries.
Although more than 15,000 people have died worldwide, the new virus turned out to be less dangerous than at first thought.
Several countries have been seeking to offload costly and unused emergency stocks of dozens of millions of doses of dedicated swine flu vaccine.