ANDREW J SPANO County Executive Joshua Lipsman, M.D., M.P.H. Commissioner, Department of Health

ATTENTION Public Health Update

The Westchester County Department of Health provides public health updates to members of the medical community on important issues affecting public health in Westchester

19 September 2003

West Nile Virus Update

· The first human case of West Nile Virus in Westchester County this year has been identified in a 74 year old female from Yonkers. No spraying for mosquitoes is planned for Westchester County at this time.

· Please report immediately by telephone to the Westchester County Department of Health (813-5000) any adult or pediatric patient with suspected viral encephalitis.

· A total of 25 human cases of West Nile viral disease have been diagnosed as of 9/18/03 among residents of the New York City metropolitan area (New York and New Jersey), including three fatal cases.

· Physicians are reminded to educate patients about taking personal protective measures against mosquito bites and eliminating standing water around their homes, particularly following the recent rainfalls. Please refer to the Physician’s Corner and West Nile Virus pages on the WCDH website (www.westchestergov.com/health) for additional information, including materials for patient education.

Please distribute to staff in the Departments of Internal Medicine, Pediatrics, Family Medicine, Neurology, Infectious Diseases, Emergency Medicine, Critical Care and Laboratory Medicine

Dear Colleagues,

The Westchester County Department of Health (WCDH) was notified by the New York City Department of Health that a 74 year old woman from Yonkers has tested positive for West Nile virus (WNV). She is currently in an intensive care unit in a New York City hospital. This is the first identified human case of WNV in Westchester County this year. The patient had the onset of symptoms and was hospitalized with fever, mental status changes, muscle weakness, and CSF pleocytosis on 9/12/03 in a New York City hospital, where laboratory tests were performed. Neurological consultation and a lumbar puncture with CSF with increased protein and WBC, with a predominantly lymphocytic differential, confirmed meningo-encephalitis and proximal muscle weakness. The patient’s serum tested positive for IgM antibody to WNV; testing of CSF for WNV is still in progress. The patient does not have a history of recent travel outside of Westchester County and spends the vast majority of time at her home. She also has no history of recent transfusions or organ transplantation. At this time, the Westchester County Department of Health is continuing to investigate the case.

Regional and Westchester WNV Update

Twenty-nine human cases of WNV disease have been confirmed in New York State, 23 of which are residents of the NYC metropolitan area and 6 are upstate. In addition to the one case in Westchester County, these cases have been identified in New York City (14 cases, one death), Nassau County (five cases), and Suffolk County (three cases, one death). Six cases have been identified in New Jersey, two of which are in the NYC metropolitan area, and four cases have been identified in Connecticut but not in direct proximity to Westchester County. Information on national surveillance can be found at the Centers for Disease Control and Prevention site: http://www.cdc.gov/ncidod/dvbid/westnile/index.htm

West Nile virus activity has also been detected in birds and mosquitoes throughout Westchester County (see Table 1). In response to the human case and these findings, the Westchester County Department of Health will be conducting additional local environmental assessment including monitoring in the area of the woman's home for potential mosquito breeding grounds, assessing the need for additional larviciding in and around Yonkers, and conducting additional mosquito trapping in the area. The Westchester County Department of Health continues to review ongoing mosquito, bird and human surveillance data. No spraying for mosquitoes is planned for Westchester County at this time.

During 2002, the possibility of WNV transmission via blood products and organ donations occurred. The Westchester County case does not appear to be linked to the receipt of organs or blood products. At present, organs and blood products are being screened for WNV before being released for use.

For further information on WN virus and transfusions, please see the CDC (http://www.cdc.gov/ncidod/dvbid/westnile/qa/transfusion.htm) and FDA (http://www.fda.gov/oc/opacom/hottopics/westnile.html) websites.

This is currently the time of greatest risk for acquiring WNV infection. WCDH continues to request that physicians remain alert for potential cases of WN viral disease for the remainder of the adult mosquito season (which ends after the first sustained frost).

To ensure the rapid identification of human WN virus infection, we are requesting that providers report immediately by telephone to the Westchester County Department of Health any adult or pediatric patient with suspected viral encephalitis as defined below:

a. Fever ³ 38°C or 100°F, and

b. Altered mental status (altered level of consciousness, agitation, lethargy) and/or other evidence of cortical involvement (e.g., focal neurologic findings, seizures), and

c. CSF pleocytosis with predominant lymphocytes and/or elevated protein and a negative gram stain and culture, with or without

d. Muscle weakness (especially flaccid paralysis) confirmed by neurologic exam or EMG.

WCDH also is reminding physicians of the importance of educating their patients, particularly those over the age of 50 who are at higher risk of developing more severe disease if infected with WNV, to take precautions against mosquito bites. All patients/residents should be urged to eliminate standing water around their homes. Further information and fact sheets for patients are available at WCDH website (www.westchestergov.com/health).

TO REPORT A SUSPECT CASE AND ARRANGE FOR TESTING, CALL THE WESTCHESTER COUNTY DEPARTMENT OF HEALTH AT:

(914) 813-5159 Mon-Fri 8:30 AM - 4:30 PM

(914) 813-5000 24 hours/day; 7 days/week

Table 1: Summary of West Nile Virus Findings in Westchester County to Date

West Nile Positive Results 2003 YTD
Birds	1
Mosquito Batches	14
Humans	1

The Westchester County Health Department thanks the medical and laboratory communities for their continued collaboration in the investigation of communicable diseases.

Sincerely,

Bill Terry, MPH, Epidemiologist

Belinda Ostrowsky, MD, MPH, Director of Communicable Diseases and STD

Ada Huang, MD, Deputy Commissioner

Division of Disease Control