Viruses Can Jump Between Primates And Humans
Pastor Dale Morgan
Viruses Can Jump Between Primates And Humans*
Scientists believe that HIV, the virus that causes AIDS, started out as
simian immunodeficiency virus (or SIV), and jumped to humans decades ago
when African bush meat hunters became infected by the monkeys they were
hunting for food.
Seattle WA (SPX) Sep 04, 2006
Viruses that jump the species barrier between monkeys and humans can
harm both people and animals, and we should take steps to reduce the
risk of virus transmission. That's the message running through the
Sepember issue of the American Journal of Primatology, a special issue
on disease risk analysis edited by a primate expert at the University of
Washington.
The special issue covers a range of topics, including an estimate of the
viral transmission risk for visitors to a monkey temple in Indonesia,
and a study showing how methods to limit contact between monkeys and
humans can reduce the risk of transmission between the species. Other
researchers describe how human viruses infecting monkeys and apes can
wreak havoc on those animals' populations.
"Viruses are already jumping the species barrier and affecting both
people and animals, and there is the potential for much worse,"
explained Dr. Lisa Jones-Engel, a research scientist in the Division of
International Programs at the UW's Washington National Primate Research
Center and guest editor for the journal's special issue. "It's
especially cause for concern in Asia, where people and monkeys have so
much interaction, and there has been little research done on this topic."
Scientists believe that HIV, the virus that causes AIDS, started out as
simian immunodeficiency virus (or SIV), and jumped to humans decades ago
when African bush meat hunters became infected by the monkeys they were
hunting for food. Other viruses, like influenza, have also jumped
species barriers with frightening results.
In one article, researchers estimate that about six people out of every
thousand who visit a monkey temple in Bali, Indonesia, will be infected
with simian foamy virus (SFV) from a monkey bite. SFV is a primate
retrovirus that so far has not been shown to cause disease in humans.
Monkey temples are religious sites that have become gathering spots for
populations of wild macaque monkeys fleeing deforested areas.
"This study is basically the first step in quantifying the risk
associated with human-to-monkey viral transmission," said lead author
Dr. Gregory Engel, attending physician at Swedish/Providence Hospital in
Seattle, and clinical assistant professor of family medicine at the UW.
"We have a lot more work to do in determining the risk of viruses
jumping the species barrier in these different settings, but the risk is
obviously there."
In addition to bushmeat hunting, people are in close contact with
monkeys in many settings in Asia: religious temples, open-air markets,
street performances, nature preserves, zoos, and even homes, where
monkeys are kept as pets. Each of these settings could provide entry
points for monkey viruses like SFV to infect humans, or for human
viruses like measles to jump to monkeys. Either population can be at
risk from these transmissions: measles can devastate monkey populations,
while some monkey viruses can also harm people.
Though SFV and a similar primate virus called SRV are not yet known to
cause disease in humans, both are retroviruses, which are typically
slow-acting in their host. It could be many years before physicians know
the effects of those virus exposures. Other viruses carried by monkeys
can cause disease and death in humans.
Visitors to monkey temples shouldn't avoid monkeys at all costs, Engel
said, but they should use caution and common sense to keep themselves
and the animals safe. People should not feed the monkeys or encourage
the animals to climb on them. Such precautions can help reduce the risk
of exposure. In the event of a bite or scratch, proper wound care can
reduce the likelihood of infection, he said.
"Governments and non-governmental organizations can also take steps to
reduce the risk of virus transmission," said Jones-Engel. "Better
management of monkey populations, disease surveillance of human and
primate populations, and improved public sanitation can all cut down on
the risk of viral transmission within monkey populations, and between
animals and people."