China is close to approving homegrown swine flu vaccines that manufacturers said that they can protect people with a single dose, an encouraging development for health officials racing to prepare for an expected spike in cases this winter, according to AP. Experts said China's versions could boost global efforts to fight the virus if claims they work with just one dose are proven. Many health authorities have assumed two doses would be needed to offer complete protection against the new H1N1 virus, so a single-dose vaccine means producers could distribute supplies to more people more quickly. The World Health Organization said it was encouraged after reviewing details of trials of one of the two Chinese vaccines. However, experts said more test results were needed from other vaccine makers around the world to determine if one dose would be potent enough. «Everybody is desperately hoping that one will do because then that's much easier to administer,» said Jodie McVernon, a vaccine expert at the University of Melbourne who is involved in Australian trials of swine flu vaccines for young children. She said she had not seen the Chinese trial results. China's State Food and Drug Administration said at least two vaccines are near approval after completing clinical trials last month and passing reviews by panels of about 40 experts this week. Another four vaccines are being reviewed, according to the agency. The vaccine makers, Sinovac Biotech Ltd. and Hualan Biological Engineering Inc., said the clinical trials show they are effective in single doses when used on people aged 3 to 60 years. International health experts say swine flu has not been as severe as initially feared. At least 2,185 people have died, but most other cases are mild and require no treatment. Worries remain that a rash of new infections could overwhelm hospitals and health authorities, particularly in poorer countries. In about two weeks, the U.S. expects to announce initial trial results from its vaccine, which is the same type as China's Sinovac version, said Dr. Anthony Fauci of the National Institutes of Health, who is overseeing American swine-flu vaccine tests. «From what I've seen and heard of the data, it looks encouraging,» Fauci said of Sinovac's clinical trials. «This is very good news. Let's hope the material that we're using has similar results.» WHO said information provided by Sinovac shows that in trials, the vaccines were tested in three formulations of 15 microgram doses, and all gave antibody responses that satisfied regulatory criteria. «We have no reason to doubt what Sinovac is reporting,» said Melinda Henry, a WHO spokeswoman in Geneva. «Certainly if one dose proves sufficient to produce the desired immune response, this would be very encouraging in terms of augmenting the global supply of vaccine in the near future.» China aims to have enough swine flu vaccines for 5 percent of its population by the end of the year, Health Minister Chen Zhu said at a recent flu symposium in Beijing.
