The swift response from virologists and geneticists to last year's epidemic of severe acute respiratory syndrome (SARS) should now give way, say some experts, to a go-slow approach on testing vaccines.

This article reports that although several vaccines are now in hand, many researchers feel they have still not found a suitable animal for testing. This has not deterred the Beijing-based Sinovac Biotech, which plans trials of an inactivated form of the SARS virus in humans this month.

At a recent World Health Organisation meeting, several SARS researchers said this is too soon. They pointed out that vaccines can make the disease worse, as happened with a feline vaccine against another similar virus. While recommending animal testing, the meeting eventually concluded that China's vulnerability to a new outbreak justifies its going ahead with human trials. 

Link to full article in Science

Reference: Science 303, 944 (2004)