keesan@bbncc5.UUCP (Morris M. Keesan) (10/17/85)
From the October 5, 1985 issue of SCIENCE NEWS, The Weekly Newsmagazine of
Science: reproduced without permission
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AIDS: Casual contact exonerated
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Research findings on AIDS at the Interscience Conference on Antimicrobial
Agents and Chemotherapy (ICAAC) in Minneapolis this week covered the gamut from
good to bad to surprising. The good news: The syndrome is apparently not
transmitted through casual household contact and hence not among school
children; health care workers who handle AIDS patients, even workers who have
accidentally stuck themselves with needles, have little if any chance of
becoming infected, according to researchers.
The bad news: Heterosexual transmission, at least in Haiti and Africa, is
becoming increasingly prevalent. And the surprising news: The virus
associated with the disease may have been around as long ago as 1962.
A Centers for Disease Control (CDC) study of 101 members of households that
included an AIDS sufferer shows transfer of infection only in one instance, in
a baby born to an infected mother. "From this study," says Martha F. Rogers of
the CDC in Atlanta, who headed the study, "our best estimate of the risk of
household transmission is zero." The belief that AIDS victims in schools can
transmit the disease, she says, has no scientific basis in the data collected
thus far.
Three studies presented at the meeting show little if any risk to health
care workers involved with AIDS patients. In a CDC study of 802 workers
nationwide who had been exposed to AIDS blood or body fluids, only one person
with no other risk factors was infected with the virus; of 527 health care
workers in two prospective studies, only 1 of 95 workers who had accidentally
stuck themselves with a needle, showd evidence of exposure. The incidence
might be so low because it takes repeated exposures or an overworked immune
system to allow the virus to establish itself, researchers suggested.
Heterosexual transmission is establishing itself as a mode of infection in
Haiti and Africa. In Haiti, 14 percent of AIDS victims in a 1980-1982 survey
were women; thus far in 1985, 36 percent are women, reports Warren D. Johnson
Jr., of Cornell Medical College in New York City. When the researchers
questioned AIDS patients about recent deaths of spouses, they found 5 percent
had spouses who died of confirmed AIDS and another 15 percent had died of what
seemed to be AIDS.
A study in Kenya, which has not reported a high AIDS incidence, shows the
virus is establishing itself among prostitutes at an alarming rate. Of 64
women who served a "lower class" clientele, 42 had AIDS antibodies, while 8 of
26 with a "higher class" clientele had antibodies; no overt disease has yet
been seen.
Where the virus comes from remains to be solved, but a report at the
meeting may add 10 years to its age. J.A. Epstein and colleagues at the Food
and Drug Administration reported finding AIDS-specific antibodies in two of 544
blood samples collected in Upper Volta in 1963--10 years earlier than
previously reported Ugandan samples (SN:3/16/86,p.173). Whether this means the
AIDS virus itself was present, or just a similar virus, remains to be seen,
Epstein says. --J. Silberner
--
Morris M. Keesan
keesan@bbn-unix.ARPA
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