Media Release

For: Immediate Release
Date: October 15, 2003
Contact: Robert J. Marshall Jr., Ph.D. 401-222-1017n Case of West Nile Virus

HEALTH Reports Two Human Cases of West Nile Virus 
Rhode Islanders Urged to Avoid Mosquito Bites

Today, the Rhode Island Department of Health (HEALTH) announced confirmation of two additional human cases of West Nile Virus (WNV) for 2003. The cases of viral meningitis, caused by WNV, occurred in two senior adults, one male and one female, both from Providence County. Both patients are receiving active medical treatment. Exposure to WNV-infected mosquitoes occurred sometime in late September with a 3 to 15 day period between exposure and the onset of illness in these two cases on October 2 and 5. Neither patient traveled out of state during this time. Due to patient confidentiality, officials declined to release additional information about these cases.

This report brings to five the number of human WNV cases reported in RI during 2003. The previous three cases occurred among adults living in Providence (2 cases) and Newport counties (1 case). HEALTH received laboratory confirmation of the most recent West Nile Virus cases from the Department of Health Virology Laboratory on October 15, 2003. Confirmation of the disease as WNV does not materially affect the type of treatment a patient receives.

"We are getting close to the end of the mosquito-biting season," said Patricia A. Nolan, MD, MPH, Director of the RI Department of Health. "Until that happens, everyone, particularly the elderly who are most likely to become seriously ill, needs to take WNV prevention measures extra seriously".

The Department of Environmental Management (DEM) and HEALTH are cautioning that residents and visitors statewide step up personal protection from mosquito bites and restrict or curtail outdoor activities during those increasingly infrequent conditions when biting activity is high. These are typically around dawn and dusk at temperatures above 50 degrees.

Mosquito numbers are clearly down, as is mosquito-biting activity. However, there are still infected mosquitoes in the environment and biting activity will increase on warm days. DEM and Health officials suggest that public officials across the state monitor weather conditions and consider rescheduling outdoor public assemblies when temperatures are expected to remain above 50 degrees at dusk.

Biting activity depends on several conditions. It is generally greatest at dawn and dusk. During the day it decreases at lower temperatures and increases at higher temperatures. Biting activity also generally increases with humidity and shade and decreases with the wind.

Protection includes using mosquito repellent, covering up when in the woods or when mosquito-biting activity is greatest, placing mosquito netting over playpens and carriages outside, and being sure that screens are in good repair.

As of October 14, 2003, the National Centers for Disease Control and Prevention (CDC) reported that 6807 human cases of WNV with 145 deaths occurred nationwide during 2003. Onset of illness generally ranges from early July to the end of season, usually in late October or when the first hard frost occurs. For general information about WNV in Rhode Island, the public may call the Family Health Information Line at 1-800-942-7434 or go to the HEALTH website at www.HEALTH.ri.gov