Increased Cases of West Nile Virus in Massachusetts

The Massachusetts Department of Public Health recently announced they’ve seen four new human cases of West Nile virus in the state this year, after five human cases were reported all of last year, indicating a significant increase of virus activity is occurring in mosquitoes.

This year, 29 other states also reported increases in West Nile Virus according to data from the Centers for Disease Control and Prevention.

West Nile Virus can be transmitted from the bite of an infected mosquito to humans and animals like birds, horses, and pets.

While a majority of people infected, four out of five, will experience no symptoms, approximately 20% of people affected will experience flu-like symptoms, such as fever and muscle pain.

The virus can also be ’neuroinvasive’ in around one in 150 people who may develop serious illness, as the virus can impact the central nervous system and cause inflammation of the brain, or membranes that surround the brain and spinal cord. 

The Massachusetts Department of Public Health said the increases in cases are likely due to the summer weather which is favorable for mosquito activity, and that there will be continued risk of contracting the West Nile virus until the first hard frost of winter. 

Although there is no vaccine available for the virus, the department recommends preventative measures such applying an EPA-registered repellent called DEET, which uses an oil of lemon eucalyptus, before going outdoors.

The department also recommends wearing long sleeves or pants and socks to keep mosquitos away from skin, and to be aware of peak biting mosquito hours from dusk to dawn. 

To mosquito-proof a home from invasion, the department recommends draining standing water like emptying rain gutters, unused flowerpots, wading pools, and installing or repairing screens around windows. 

In other states, like Utah, there has been an increase in human cases of West Nile Virus and concerns about increases of positive West Nile Virus mosquito pools.

The latest numbers from the Utah Department of Health show that 506 pools of mosquitoes tested positive for West Nile this year, and there have been six human cases recorded.