September 28, 1985

LAV/HTLV-III, the agent causing AIDS, has been isolated from body

fluids (blood, semen, saliva, tears). Its isolation in saliva

prompted us to investigate the possibility of TRANSMISSION BY

SALIVA, and we have studied the sensitivity of LAV/HTLV-III at room

temperature.

The virus used for the infectivity assay was left at room

temperature for 0, 2, 4, or 7 days in a sealed tube or ALLOWED TO

DRY in a petri dish.

After the times indicated in the figure the virus was used to infect

stimulated T lymphocytes and viral production was determined in

cell-free supernatant by testing for the reverse transcriptase

activity twice a week.

[The data] shows the UNUSUAL STABILITY of HTLV-III at room

temperature. No significant difference was found between 0, 2, or 4

days. Only a slight decrease is noted with a delay in the virus

production indicating a loss of few infectious particles after 7

days at room temperature.

Two petri dishes containing 25,000 cpm equivalent reverse

transcriptase of dry virus were kept at room temperature for 4 or 7

days and then resuspended in .220 ml water and used to measure the

infectivity.

As [the data show], significant numbers of viral particles are then

inactivated, but some infectious virus is still present since

release of virus was seen on day 10. This result indicates that the

virus is RESISTANT AT ROOM TEMPERATURE, either in DRY form OR LIQUID

medium.

This resistance of LAV at room temperature MAY EXPLAIN THE

APPEARANCE OF SOME CASES of AIDS cases in NON-RISK GROUPS.

To prevent possible contamination by viral particles in dry or

liquid form hygiene should be increased in the general population.

Moreover, some more safety precautions should be taken in

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laboratories and in hospitals and by dentists who use a vacuum pump

for saliva aspiration. Indeed, these data strongly support the use

of disinfectants found to be effective against the AIDS agent.

[F. Barre-Sinoussi et al., Resistance of AIDS Virus at Room

Temperature, Lancet,

28 September 1985, pp. 721-722.]