MONTREAL -- How long should you or your child stay at home after coming down with swine flu?

Quebec researchers attending the American Microbiology Association conference in San Francisco Tuesday unveiled results of a preliminary study looking at the contagious reach of influenza A H1N1, the so-called swine flu virus.

It appears that the virus remains “live” -- or transmissible -- for at least eight days in up to 15 per cent of the population infected with the virus.

“Once your fever disappears, you are still likely to be contagious three days after,” said medical epidemiologist and study co-ordinator Gaston De Serre of the Quebec Institute of Public Health.

Researchers took mouth and nose swabs from 65 families from May to July to see whether patients with H1N1 infections still harbour the virus a week after symptoms strike.

The study was presented at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.