UMass Medical School tapped to study West Nile virus


Center for Infectious Disease and Vaccine Research to investigate disease process


October 30, 2002


WORCESTER, Mass. ─ Researchers at the University of Massachusetts Medical School have been awarded a seven-year, $3.1 million subcontract to investigate the disease process of West Nile virus, seeking clues as to why the virus causes serious illness and death in some people, while in others it manifests itself with simple flu-like symptoms. The University’s findings may lead to targeted treatment and prevention of the disease.


The study is part of a National Institutes of Health initiative awarded to the New York Department of Public Health entitled, “U.S. Based Collaboration in Emerging Viral and Prion Diseases.”  UMMS faculty have long been interested in emerging and re-emerging viral pathogens, particularly flaviviruses such as dengue, yellow fever, Japanese encephalitis and now, West Nile, which is borne by mosquitoes and birds.  Under the leadership of Professor of Medicine Francis Ennis, MD, director of the UMMS Center for Infectious Disease and Vaccine Research, scientists will investigate the molecular mechanisms by which the virus causes infection and the immune system’s response to it.


Associate Professor of Medicine Sharone Green, MD, working with health agencies in regions struck by the disease, has begun to obtain blood samples from infected individuals in order to examine the role of West Nile virus-specific T lymphocytes, the cells responsible for orchestrating the immune system’s response to infected or malignant cells. In understanding the immune system’s interaction with the virus, she and her colleagues hope to uncover the reasons why some individuals are unable to combat the virus effectively. Although advanced age—and the attendant decrease in the effectiveness of the immune response—appears to be a risk factor for severe disease and mortality, the precise immune


and viral mechanisms that underlie the basic disease process are largely unknown. “We hypothesize that the level of T lymphocyte responses to West Nile virus is lower in individuals who experience severe disease,” said Dr. Green. “This decreased ability to fight the virus in the bloodstream may lead to virus invasion into the brain.”


The ultimate goal of the collaborative studies is to determine the role of the immune system in disease pathogenesis, and to elucidate how T lymphocytes can protect individuals. Investigators expect that the study of the natural history of T lymphocyte responses in humans will be invaluable in the development and testing of future West Nile virus vaccine candidates.


In conjunction with CIDVR’s work, researchers at the Wadsworth Center in Albany will lead an investigation of the ecology of West Nile virus, including the study of climactic factors, mosquito and bird infection rates and migration patterns.  Although first isolated in Uganda in 1937, West Nile virus was not seen in the United States until 1999, when 62 cases were identified in New York City. The disease gained widespread notoriety as crows infected with West Nile virus were found in New York and then New England, and in the last three years the disease has spread across the continent, causing outbreaks from New Hampshire to California. This year, more than 2,000 cases of illness due to West Nile virus infection have been identified.


The University of Massachusetts Medical School, one of the fastest growing academic health centers in the country, has built a reputation as a world-class research institution, consistently producing noteworthy advances in clinical and basic research.  The Medical School attracts more than $134 million in research funding annually, 80 percent of which comes from federal funding sources.  Research funding enables UMMS scientists to explore human disease from the molecular level to large-scale clinical trials.  Basic and clinical research leads to new approaches for diagnosis, treatment and prevention of disease.




Alison Duffy, 508-856-2000