DATE: Friday, November 21, 1997             TAG: 9711210624

SECTION: LOCAL                   PAGE: B12  EDITION: FINAL 

SOURCE: ASSOCIATED PRESS 

DATELINE: RICHMOND                          LENGTH:   49 lines

OFFICIALS STUDY MICROBE THAT GAVE FISH SORES, TEST FOR HUMAN DANGER SCIENTISTS HUNT FOR THE ACANTHAMOEBA STRAIN THAT SICKENED JAMES RIVER FISH.

Scientists are studying a microbe found in dozens of sick fish in the James River to determine whether it can kill people, a Virginia Commonwealth University researcher said Thursday.

Greg C. Garman, a VCU fish biologist, said the one-cell microbe Acanthamoeba caused large sores on the fish. He said there are about 10 species of Acanthamoeba, but only about half have been identified with human health problems and just a couple have killed people.

Human deaths from the microbe are rare. Only 200 fatalities worldwide in the past 20 years have been attributed to Acanthamoeba. None of those deaths occurred in Virginia.

Garman said it could take researchers anywhere from two days to several weeks to determine which species of the microbe affected the fish, which were collected from the river near Richmond in May and September.

Dr. Suzanne Jenkins, acting state epidemiologist, said Acanthamoeba is one of many amoebas routinely found in water and moist soil, and the threat to human health probably is negligible.

The discovery of the sickened fish raised fears of an attack by pfiesteria, a microbe that has killed millions of fish in North Carolina and Maryland. Pfiesteria is suspected of causing memory loss in humans but is not considered deadly.

Garman said this is the first known Acanthamoeba infection of fish since 1977, when the microbe killed thousands of fish in Florida and Alabama. None of the fish taken in Virginia was dead.

Acanthamoeba can cause a form of encephalitis, a deadly brain inflammation, in humans. Jenkins said it reaches the brain through the bloodstream, perhaps after being absorbed through the skin.

She said people with impaired immune systems are most in danger of contracting encephalitis.

Garman said cooking and eating a fish infected with Acanthamoeba would not make a person ill, but handling a fish with open sores might.

The microbe also can cause keratitis, an eye disease that can lead to blindness. People with unclean contact lenses can get the eye infection.

Naegleria, another microbe that is similar to Acanthamoeba, killed 16 people in Virginia between 1937 and 1969, Jenkins said. She said Naegleria can afflict people when water is forced into their nose, usually when diving or swimming.

Garman said researchers will investigate whether high levels of fecal bacteria cause high concentrations of Acanthamoeba.

Send Suggestions or Comments to webmaster@scholar.lib.vt.edu