A 46-year-old woman from Suffolk County, Massachusetts, is the first human case of West Nile Virus in the state this year, reports the Department of Public Health. The woman developed symptoms on August 18th and was sent to hospital two days later. Doctors say she has improved and will be able to go home soon.

There was also a case of Eastern Equine Encephalitis (EEE). A 43-year-old man from Pymouth Country developed symptoms on August 21st and was hospitalized two days later. He is still in hospital, health authorities inform. He was exposed to an EEE infected mosquito in the southeastern section of Massachusetts; an area identified as having a higher risk for mosquito-borne illness. Aerial spraying has been carried out in Plymouth country.

There have been 10 cases of reported West Nile Virus human infections in Massachusetts over the last five years.

West Nile Virus, also known as WNV, is a virus of the family Flaviviridae which is spread by the bite of infected mosquitoes. The Flaviviridae virus family also includes Japanese encephalitis, yellow fever and dengue fever.

West Nile Virus mainly affects birds – but can also infect other animals, including horses, dogs, cats, bats, skunks, squirrels, chipmunks and domestic rabbits. Humans may also be infected.

Most infected humans either experience no signs or symptoms, or just a skin rash and headache. A small percentage of infected individuals, however, may develop a life-threatening illness which may include encephalitis (inflammation of the brain), myelitis (inflammation of the spinal cord), or meningitis (inflammation of tissues surrounding the brain and spinal cord). Experts say approximately 1% of infected humans develop these serious complications. Those at highest risk for serious illness are the elderly and those with lowered immune systems.

Eastern Equine Encephalitis, also known as EEE, is a mosquito-borne viral disease. The virus thrives in freshwater swamp birds and non-human-biting mosquitoes. The mosquitoes can sometimes infect other mosquitoes that do bite humans and other animals, such as horses. According to the Centers for Disease Control and Prevention, risk of infection is highest from the middle towards the end of summer. Initial symptoms include a high temperature (fever), stiff neck and headache. Encephalitis (swelling of the brain) may follow. The disease may worsen rapidly, and some patients may go into coma. If there are complications the patient may die.

In 2009 there were no reported cases of human EEE infection. From 2004 through 2006 there were 13 cases, of which 6 died. Department of Public Health State Epidemiologist Dr. Alfred DeMaria, said:

Every year, we always hope that there won’t be any cases of either of these mosquito-borne illnesses. But when they occur they serve to remind us of how important it is to take steps to protect ourselves and our families. We always recommend that people use mosquito repellant and cover up when outdoors, no matter where they are.

Source: Commonwealth of Massachusetts

Written by Christian Nordqvist