107-AP-00

FOR IMMEDIATE RELEASE

ANTIVIRAL DRUG FOUND EFFECTIVE AGAINST VIRUS THAT CAUSED NEW YORK ENCEPHALITIS OUTBREAK

Treatment Now Used Against Viruses in Children May Be Effective in Elderly, Others Susceptible to West Nile Infection

Irvine, Calif., July 20, 2000 -- A drug currently used to fight other viral diseases also may be effective against the West Nile virus that caused the outbreak of encephalitis in New York last summer, a UC Irvine research team has found.

The findings from a study conducted on human central nervous system cells suggest that the antiviral drug ribavirin may be an effective treatment for the elderly and others who are more susceptible to the encephalitis-causing virus, which killed seven people in the New York City area last summer and recently was found in mosquitoes caught in the area. The researchers' findings will appear in an upcoming issue of the Journal of Infectious Diseases.

Dr. Ian Lipkin, the Louise Turner Arnold Chair in the Neurosciences, and his team from UCI and ICN Pharmaceuticals in Costa Mesa, Calif., found that high doses of ribavirin resulted in significantly lower levels of the genetic material of the West Nile virus in infected cells and reduced damage due to West Nile virus infection. In cells that were not infected with the West Nile virus, doses of the drug did not appear to cause any cellular damage, indicating that treatment may produce few side effects in the central nervous system.

"To our knowledge this is the first drug to have specific activity against the West Nile virus," Lipkin said. "The results are encouraging and suggest that it may be possible to prevent deaths and illness from West Nile virus encephalitis."

Ribavirin is manufactured by ICN Pharmaceuticals and used mainly for treating severe childhood viral infections. It also has been used occasionally to treat severe viral infections in adults, including Lassa Fever, yellow fever, Japanese encephalitis and hepatitis C. Lipkin cautioned, however, that because ribavirin never has been used on West Nile infections and has been known to produce some side effects, any treatments with the drug should be monitored very closely by a physician.

"The drug can cause temporary anemia in high doses and doctors should monitor its use carefully, and further animal testing is necessary to determine its exact functions against this virus," said Lipkin. "But it may be useful in helping prevent deaths in people who are more vulnerable. While we are excited by our results with ribavirin, we hope our findings will aid in the development of other drugs that have more specific activity against the West Nile virus."

Lipkin and his team, along with the Centers for Disease Control in Fort Collins, Colo., discovered the West Nile virus as the agent responsible for causing last August's encephalitis outbreak. Lipkin's researchers also have developed a quick, accurate diagnostic technique that a hospital laboratory can use to determine the existence of West Nile infection.

The West Nile virus, which was never seen in the United States until last August, is an example of the spread of infectious agents over the earth, causing what is known as "emerging infectious disease." Due to mutations and other changes in disease-causing viruses, bacteria and other organisms and the increasing ease of travel around the globe, health professionals are finding increasing incidences of these once-exotic diseases.

Lipkin's colleagues included Ingo Jordan, Thomas Briese and Nicole Fischer at UCI, and Johnson Lau at ICN Pharmaceuticals.

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Contact: Andrew Porterfield
(949) 824-3969
[email protected]

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