The Massachusetts Department of Public Health (MDPH) has reported the fourth human case of West Nile Virus (WNV) in a resident of Norfolk County. Additionally, MDPH has identified 163 WNV-positive mosquito samples across various counties in the state, including Barnstable, Berkshire, Bristol, Essex, Hampden, Hampshire, Middlesex, Norfolk, Plymouth, Suffolk, and Worcester.
Furthermore, there have been 27 mosquito samples that have tested positive for Eastern Equine Encephalitis (EEE) in Barnstable, Bristol, Hampden, and Worcester Counties. Due to increased EEE activity, MDPH has raised risk levels in affected regions and is conducting intensified surveillance activities.
The MDPH advises residents to stay vigilant and check their risk levels throughout the season by visiting the provided interactive site. The risk of mosquito-borne diseases, including WNV and EEE, remains until a statewide hard frost occurs. To reduce the risk of mosquito bites, individuals are encouraged to use EPA-approved repellents, wear appropriate clothing, and avoid outdoor activities during peak mosquito activity hours, which are typically between dusk and dawn. Additionally, people should take steps to eliminate standing water by emptying containers and removing tarps, as standing water provides breeding sites for mosquitoes.
WNV and EEE Virus Surveillance Summary Results contained in this report reflect data up to and inclusive of MMWR Week 40 (Sunday, 10/01/2023-Saturday, 10/07/2023) |
Mosquito Surveillance |
Number of Mosquito Samples Tested | 10534 |
Number of WNV Positive Samples | 163 |
Number of EEE Positive Samples | 27 |
Equine/Mammal Surveillance |
Number of Mammal Specimens Tested | 2 |
Number of WNV Positive Horses | 0 |
Number of EEE Positive Horses | 0 |
Number of other WNV Positive Mammals | 0 |
Human Surveillance |
Number of Human Specimens Tested | 206 |
Number of Human WNV Cases | 4 |
Number of Human EEE Cases | 0 |