MDPH Arbovirus Surveillance Weekly Reports 2021

7/7/21 Report

7/12/21 Report

7/19/21 Report Note: there were positive samples of West Nile Virus (WNV) in traps located in Middlesex County.

7/26/21 Report

8/2/21 Report

8/9/21 REPORT Note: 30 WNV positive mosquito samples collected in Barnstable, Bristol, Essex, Hampden, Middlesex, Norfolk, Plymouth and Suffolk Counties. The populations of mosquito vectors that transmits WNV and EEE are above average and increasing due to intense regional precipitation events and continued warm weather. Recommendations include: avoid mosquito bites by using EPA approved repellents, appropriate clothing and avoiding peak mosquito activity between dusk and dawn and remove standing water by emptying containers and tarps.

8/16/21 Report  Note: MDPH has identified 40 West Nile virus positive mosquito samples collected in Barnstable, Bristol, Essex, Hampden, Hampshire, Middlesex, Norfolk, Plymouth and Suffolk Counties. This is up from 30 in the prior week surveillance report. The populations of mosquito vectors that transmits WNV and EEE are above average and increasing due to intense regional precipitation events and continued warm weather. Avoid mosquito bites by using EPA approved repellents, wear appropriate clothing and avoiding peak mosquito activity between dusk and dawn.  Remove standing water by emptying containers and tarps.

8/21/21 Report  Note: MDPH has identified 57 West Nile virus positive mosquito samples collected in Barnstable, Bristol, Essex, Franklin, Hampden, Hampshire, Middlesex, Norfolk, Plymouth and Suffolk Counties. This is up from 40 WNV positive samples from last week. (42.5% increase from last week). The populations of mosquito vectors that transmits WNV and EEE are elevated due to intense regional precipitation events and average temperatures. Avoid mosquito bites by using EPA approved repellents, appropriate clothing and avoiding peak mosquito activity between dusk and dawn. Remove standing water by emptying containers and tarps.

8/28/21 Report Note: MDPH has identified 66 West Nile virus positive mosquito samples (up from 57 last week) collected in Barnstable, Bristol, Essex, Franklin, Hampden, Hampshire, Middlesex, Norfolk, Plymouth and Suffolk Counties. The populations of mosquito vectors that transmits WNV and EEE are elevated due to intense regional precipitation events and average temperatures. Avoid mosquito bites by using EPA approved repellents, appropriate clothing and avoiding peak mosquito activity between dusk and dawn. Remove standing water by emptying containers and tarps.

9/3/21 Report Note: MDPH has identified four WNV human cases in Middlesex County and 98 (up from 66) West Nile virus positive mosquito samples collected in Barnstable, Bristol, Essex, Franklin, Hampden, Hampshire, Middlesex, Norfolk, Plymouth and Suffolk Counties. The populations of mosquito vectors that transmits WNV and EEE are elevated due to intense regional precipitation events and average temperatures. Avoid mosquito bites by using EPA approved repellents, appropriate clothing and avoiding peak mosquito activity between dusk and dawn. Remove standing water by emptying containers and tarps.

9/10/21 Report Note: Risk Level Changes after first animal tests positive for WNV in Middlesex County. Read more here.

9/13/21 Report

9/28/21 Report