China expected to receive seed viruses of A(H1N1) influenza from the World Health Organization (WHO) within this week and will start producing vaccines in mid June, said the State Food and Drug Administration (SFDA) on Wednesday.

If the transport of seed viruses and production of vaccines go smoothly, the country will have its first batch of A(H1N1) influenza vaccines as early as in late July, said Yin Hongzhang, head of the SFDA biology production office.

"We are still waiting for the WHO to make the decision on whether A(H1N1) flu should be categorized as seasonal or pandemic," Yin said.

China has 11 flu vaccines manufacturers, but only one of them is qualified to produce pandemic vaccines.

If it is a seasonal flu vaccine, the first batch will be 3 million doses and annual production 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, he said.

WHO Assistant Director-general Dr. Keiji Fukuda said on 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.

"Provided that WHO has not issued the guidance, we have decided to prepare for pandemic vaccine production first," Yin said.

The SFDA asked the qualified drug company to stand by and the rest companies should also be ready to help, he said.

The Chinese mainland reported 51 cases of A(H1N1) influenza as of Wednesday evening.

(Xinhua News Agency June 4, 2009)