Mosquito-Borne Diseases and the Elderly

As the summer season rolls around once again, officials in southern New England are beginning to test for Eastern Equine Encephalitis (EEE) and West Nile Virus (WNV). Thus far, testing has turned up no mosquitos carrying EEE or WNV in Rhode Island, Massachusetts, or Connecticut. But it is early in the season and officials report that most cases occur from late July through October.

"Mosquitos, small as they are, are responsible for between 800,000 and a million deaths annually worldwide, according to the World Health Organization," said certified elder law Attorney RJ Connelly III. "Mosquitos cause more death and suffering than any other organism on earth."

"Here in New England, the most recent outbreak of EEE occurred in 2019, according to the CDC," stated Attorney Connelly. "There were thirty-two known cases that killed twelve of those infected. This disease has a 30 percent fatality rate, similar to Ebola or smallpox. Of those who do survive, nearly half will have long-term neurological complications."

"So, we wanted to provide some information on the diseases mosquitoes are responsible for including those that affect us right here in southern New England," said Attorney Connelly. "We also wanted to provide links to the CDC site that continually monitors mosquito activity in your area so you can make a safe decision about travel and vacationing. Save this link and use it during mosquito season."

Diseases Spread by Mosquitoes

Eastern Equine Encephalitis

Massachusetts is ground zero for this infection. EEE was first found in horses in Massachusetts in 1831 and in 1938, the first confirmed human cases were found here in New England. Today, EEE is present in North, Central, and South America where it is known as “sleeping sickness”.

Massachusetts is ground zero for EEE

The mosquito that carries EEE prefers to bite animals but will also dine on humans. However other mosquitoes, who do feed on both humans and animals, can carry the disease between the species. These mosquitoes include the Aedes, whom we are most familiar with.

The risk of contracting the EEE virus is highest during the summer months and those who live and work near wetland and swamp areas are at higher risk of infection. And as we stated earlier, EEE is only spread to humans via mosquito bites and not through infected animals.

"...the elderly (ages fifty and over) and the young (ages fifteen and under) are at greatest risk of developing encephalitis from EEE."

Of those who contract the EEE virus, the elderly (ages fifty and older) and the young (ages fifteen and younger) are at the greatest risk of developing encephalitis. EEE can lead to a fever, headaches, vomiting, diarrhea, irritability, drowsiness, lack of appetite, seizures, falling into a coma, and potentially death. So dangerous is this disease that one in three people who contract it do not survive. According to the CDC, death can be rapid, just 2 to 10 days after symptoms appear. Of those who do survive, nearly half are left with lingering mental and physical impairments, such as difficulty thinking, personality disorders, seizures, paralysis, and several types of nervous system dysfunction.

West Nile Virus

This year marks the twenty-second anniversary of the detection of the West Nile virus in this country. Last year, there were over 2690 cases of West Nile virus in the United States, a slight uptick from the case counts reported in the previous five summers. The last time the US saw more cases was in 2012 when there were 5674 cases reported. According to the CDC, the West Nile virus is now the leading cause of mosquito-borne disease in the continental United States. As of June 28, 2022, a total of 10 cases of West Nile virus disease in people have been reported to CDC. Of these, 7 (70%) were classified as neuroinvasive diseases (such as meningitis or encephalitis) and 3 (30%) were classified as non-neuroinvasive diseases.

Twenty two years since West Nile appeared here

This virus was first isolated in Africa in 1937 and quickly spread throughout the region. Then in 1999, a strain of the virus that was active in Israel and Tunisia was imported into New York and resulted in a huge outbreak that spread throughout the continental United States. Today, the virus has firmly established itself in this country.

The virus is transmitted by the Culex mosquito, which acquires the virus by feeding on infected birds. The strain that is active in the United States is extremely deadly for crows, so the sight of dead birds may indicate the presence of this virus in the area.

"...people older than fifty and especially those over sixty-five have the highest risk of developing encephalitis from the West Nile Virus."

About 80 percent of those who are bitten by infected mosquitoes do not develop any symptoms, but in the 20 percent who do, they develop fevers, aches, and nausea -- and about 1 in 150 of this group will develop encephalitis, a much more serious disease, which could result in death.

Unfortunately, people older than fifty and especially those over sixty-five, have the highest risk of developing encephalitis. There is no vaccine for West Nile and treatment consists of addressing the symptoms such as fever and dehydration. In severe cases, hospitalization may become necessary.

We Live in a Smaller World

"We discussed the two viruses we are most concerned with here in Southern New England, but the reality is that today’s seniors are much more mobile and are on the move around our country and the world, putting them at risk for other infections carried by these insects," Attorney Connelly points out. "Still others, who may have immigrated to this country, return home to visit family members and encounter various diseases and viruses not seen here. This includes those traveling to the Caribbean, Asia, and parts of Africa."

People are traveling again after the pandemic

“It’s great that our seniors are traveling and visiting other countries," said Attorney Connelly. “But with this travel come concerns that seniors must be aware of. This includes the infections carried by mosquitoes in parts of the world that don’t have the same standards of hygiene as we do here or have the immunity that those living there may have. Traveling does come with risks. And knowing these risks and the precautions to take may keep them safe.”

Among these risks include some of the major infections carried by mosquitoes not commonly seen in Southern New England like Zika, Chikungunya, Yellow Fever, Rift Valley Fever, Malaria, and Dengue. Let's briefly look at them.


Just a few years ago, the Zika virus made headlines about its rapid spread across the globe. Although the Zika hysteria has subsided, it doesn’t mean it has disappeared. in fact, one could argue that Zika may pose more of a risk to people than EEE and WNV because of how it can be transmitted.

Babies born with microcephaly due to Zika

Those who contract this virus usually experience no symptoms or only a mild disease that may involve fever, rash, and joint pain in most people who become infected. However, the disease can cause severe neurological defects in the developing fetuses of pregnant women who are infected with the Zika virus. A substantial number of the