00:49 Long, Hot Summer Could be Causing Outbreak of Mosquito-Borne Disease Scientists say mosquito-borne illnesses like EEE are becoming more common in a warming world.

At a Glance At least eight people have died this year from eastern equine encephalitis.

Many who recover are left with brain damage.

Scientists have warned that climate change could lead to a surge in mosquito-borne diseases. Parts of the U.S. are seeing higher than normal cases of infection and death from mosquito-borne eastern equine encephalitis, a disease that kills one-third of patients and leaves many survivors with mild to severe brain damage.

An unusually long, warm summer exacerbated by climate change may be spurring the spread of the disease, experts say.

"It’s difficult, if not impossible, to say it is cause and effect ," Theodore Andreadis, head of the Connecticut Agricultural Experiment Station’s mosquito monitoring and research program, told the Hartford Courant. "But it’s all consistent with [climate change]."

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An average of seven cases of EEE are reported each year in the U.S., and 30 percent of people with the disease usually die, according to the Centers for Disease Control. This year, there's already been at least eight deaths, according to the Associated Press.

At least 28 people have been infected with the disease so far in 2019, ABC News reported. That's more than any year since the CDC started keeping track and tops the previous record of 21 cases in 2005.

Deaths have occurred in Michigan, Massachusetts, Connecticut and Rhode Island.

The outbreak is prompting warnings about being outside at dusk and dawn, and causing outdoor activities like high school and college football games to be scheduled during the daytime hours.

In Michigan, officials planned to conduct aerial anti-mosquito spraying in four counties to combat the spread of EEE. It's the first time such action has been taken in the state since 1980, according to the AP.

The disease is carried by birds commonly found in people's backyards. Mosquitoes who bite the birds can transmit EEE to humans and other animals.

There is no cure for EEE, and many patients who recover are left with brain damage. Symptoms include chills, fever and tiredness. The disease can progress rapidly and involve swelling of the brain and convulsions, leaving patients comatose.

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Patricia "Pat" Shaw, of East Lyme, Connecticut, succumbed to EEE on Sept. 19.

"All of a sudden, she just got extreme weakness and her temperature went up to 102.7 degrees. She was very, very tired and had to lie down and went to bed early ," her husband, Gerald Shaw, told USA Today. "The next morning when she got up, she was showing some confusion."

Tests at a local hospital ruled out a stroke. Then her blood pressure spiked, and she started to have what appeared to be seizures. Further testing revealed two weeks later that she was infected with EEE, despite an earlier test that was negative.

"That gave us the bad news that ... there wasn't much hope for recovery," Gerald Shaw said.

While outbreaks of EEE tend to be cyclical, scientists have predicted that climate change could lead to a surge in mosquito-borne diseases. Changes in weather patterns help mosquitos spread to other areas, and to breed in larger numbers.

"Eastern equine encephalitis is typically a very rare disease here in the United States," Emily Shuman, an infectious disease specialist at the University of Michigan, told WBUR. "And we're seeing quite a few cases here recently in the eastern part of the country, as well as the Midwest. And it's fairly late in the season to be seeing mosquito-borne diseases. We're already well into the fall here, and these are typically more summertime diseases. So I do think this is a concerning trend."

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