Mosquito & Tick Diseases
Current Local Status
Page updated 9/24/26. MDPH currently lists Watertown at high for West Nile virus (WNV) and low for Eastern equine encephalitis (EEE).
Technicians annually apply a larval control product to storm drains in order to reduce the mosquito species that is the primary vector for West Nile virus.
They carry bacteria, viruses, and protozoa that can transfer to humans and cause diseases such as West Nile Virus, Eastern Equine Encephalitis (EEE) from mosquitos, and Lyme disease from ticks.
Prevention tips
- Be prepared: Know your risk- check this page regularly, repair screens, clean up to get rid of mosquito breeding sites, be aware of stagnant water on private property and consult with the local health department.
- Wear long sleeves and pants from dust to dawn when weather permits
- Use mosquito netting on baby carriages and playpens
- Wear mosquito repellant when outdoors, especially between dusk and dawn. https://www.mass.gov/doc/mosquito-repellents-factsheet-english/download *Chinese, Haitian Creole, Portuguese, Spanish, and Vietnamese translations of this fact sheet are available.
- Dump standing water twice weekly
- People over 50 or those who are immune compromised should adjust outdoor activity to avoid peak mosquito hours (from dusk to dawn).
To view risk level maps, visit Massachusetts arbovirus update | Mass.gov
Who needs Extra Protection?
Anyone can become infected with WNV or EEE. Some people have a greater risk of severe
illness:
- WNV: Risk increases with age. People with weakened immune systems or certain
health conditions may also have a greater risk of severe illness. - EEE: People younger than 15 and older than 50 are more likely to develop severe
illness. - People who work, exercise, or spend long periods outdoors are more likely to be exposed to mosquito bites and should take extra care to protect themselves.
Talk with a health care provider if you have questions about your personal risk.
Where Can I Get More Information?
The Massachusetts Department of Public Health (MDPH), Division of Epidemiology and Immunization at (617) 983-6800 or toll-free at (888) 658-2850, or on the MDPH Mosquito-borne Diseases website, or Watertown Public Health Department at 617-972-6446.
Health effects of pesticides, MDPH, Center for Environmental Health at (617) 624-5757
Information on repellents (such as choosing the right repellent, using repellents on children or pregnant women, or detailed toxicology information), National Pesticide Information Center (NPIC) toll free at (800) 858-7378 or online.
For additional general information, mosquito activity, and risk levels please check the Massachusetts Department of Public Health Website or the East Middlesex Mosquito Control Project Website.
Tick Removal Symptoms and Tick Prevention.
University of Rhode Island (URI) Tick Encounter
Massachusetts Department of Public Health Tick-Borne Disease Prevention Resources