A Chinese drug firm has received seed viruses of A/H1N1 influenza from the World Health Organization (WHO), the State Food and Drug Administration (SFDA) confirmed?Thursday.

Hualan Biological Engineering Inc., the only firm qualified to produce pandemic vaccines, received seed viruses from a WHO lab on Wednesday night, said Yin Hongzhang, head of the SFDA biology production office, in an interview with Xinhua.

"Among the rest of the 10 flu vaccines manufacturers, which are qualified to produce seasonal flu vaccines, some also applied to WHO for seed viruses," Yin said. "They will also receive the seed viruses soon."

Hualan has started producing undiluted vaccine solution last night, Fan Bei, Hualan's deputy general manager, told Xinhua. "We will continue studying which form and dose the vaccines should be. We will arrange the production according to the guidance of the SFDA and WHO."

Yin expected the first batch of vaccines will be produced as early as in late July.

But the country was still waiting for the WHO to make the decision on whether A/H1N1 flu should be categorized as seasonal or pandemic.

If it is a seasonal flu vaccine, the first batch will be 3 million doses and the annual output can reach 360 million. But, for a pandemic vaccine, the first batch will only be 250,000 doses and annual production will be 27 million, Yin said.

WHO Assistant Director-general Dr. Keiji Fukuda said Tuesday in Geneva that WHO is getting closer to declaring a full pandemic of A/H1N1 flu.

Seasonal flu occurs annually in predictable patterns, allowing people to develop resistance, while pandemic flu is rare, meaning that it's hard for people to develop resistance. In the latter case, vaccine doses need to be higher to be effective.

The Chinese mainland reported 59 cases of A/H1N1 influenza and one suspected case as of Thursday afternoon.

(Xinhua News Agency June 4, 2009)