SARS epidemic continues
Two strains of the virus responsible for severe acute respiratory syndrome (SARS) have been sequenced. As health authorities work to halt the epidemic, researchers from Canada and the United States have discovered the sequences of TOR2 and Urbani.
The TOR2 strain is made up of 29 751 bases and, apart from 8 bases, is identical to Urbani's sequence. The two teams disagree as to which is correct. No conclusive clues have been found concerning the potential animal origin of the pathogen. This coronavirus cannot be classified in the three known groups of the family; researchers suggest that SARS CoV may be the first member of a fourth group.
On 14 May, Toronto was taken out from the list of areas with recent local transmissions and was removed from the list of places with strict recommendations for international travellers. This was based on the observation that more than 20 days have