[ad_1]
A deadly virus transmitted by a mosquito, responsible for Eastern Equine Encephalitis (EEE), infected an eighth person in Massachusetts, a state particularly affected by the disease, Ministry of Public Health announced on September 13.
On average, only seven cases of EEE are reported in the United States each year, according to the Center for Disease Control and Prevention (CDC). This year, the virus killed three people, including a woman from Massachusetts. So why is Massachusetts taking the weight of the virus?
The state of New England has one of the highest concentrations of red maple swamps and white cedar trees on the east coast. "These swamps are the engines of EEE activity," said Dr. Catherine Brown, an epidemiologist in the state of Massachusetts.
Here's why: EEE-infected birds migrate every year from Florida, where the EEE is also a problem, to New England. These birds prefer to live in swamps of red maple and white cedar, just like a particular species of mosquito that feeds primarily on birds. When establishing near these marshes, the birds turn into blood for mosquitoes, which then contract the virus.
Related, connected, related: 27 devastating infectious diseases
Other species of mosquitoes that feed mainly on mammals sometimes also feed on birds, thus becoming the gateway for the virus to pass from birds to mammals, such as horses and humans. Humans and horses are "accidental" and "dead-end" hosts, and the virus has nowhere to go, Brown said.
The virus does not kill birds, and after two or three years they acquire immunity against the EEE. Once this happens, the virus does not spread efficiently among birds and does not travel much, so the state is experiencing a period of lull.
But then, the proportion of immunized birds begins to reverse, with immunized birds dying of old age and young children becoming vulnerable. In addition, migratory birds occasionally bring in a slightly different strain of EEE, to which no bird is immune. Taken together, these factors cause epidemics in Massachusetts every 10 to 20 years and can last for several years.
In humans, the virus invades the central nervous system and causes inflammation in the brain. About 30% of people who contract EEE die and many who survive have persistent neurological problems, according to the report. CDC.
"At present, no specific drug is known to treat IAS," Brown said. Nevertheless, this disease is very rare. each year, there are generally only an average of seven cases identified throughout the United States. Other viruses are also threatened by the virus at the origin of the EEE – the other two deaths occurred in Michigan (two people suspected of being infected) – and Rhode Island, the only confirmed human case of the state since 2010.
The mosquito season in New England is coming to an end and normally EEE infections have also almost dropped until mid-September. However, "I think everyone is nervous about this year" because it's especially prevalent, Brown said. The state sprays pesticides to get rid of mosquitoes in high-risk areas.
The best prevention for EEE is to avoid mosquito bites, Brown said. She recommends the use of anti-mosquito products, clothing covering the body on the outside and evacuate any stagnant water conducive to mosquito larvae. in the higher risk areas from Massachusetts, she recommends people avoid outdoor activities from dusk to dawn.
Originally published on Science live.
[ad_2]
Source link