Dengue, EEE, West Nile Virus Among Mosquito-Borne Diseases on the Rise, as Weather Prolongs Breeding Season

Dengue, a blood-borne disease spread by mosquitoes, has hit Pakistan hard with 20,000 cases and 34 confirmed deaths, according to Radio Free Europe. Rana Muhammad Safdar of the National Institute of Health says the epidemic has strained hospitals across the country.

The World Health Organization says dengue, also called dengue fever, is a virus that presents with severe flu-like symptoms, the main one being a high fever. If left unchecked, the disease can turn into severe dengue, which can lead to plasma leakage, severe bleeding or organ impairment among other symptoms.

The Aedes aegypti mosquito is the prime carrier of dengue, which spreads to humans via bites from infected females. The mosquitoes are prevalent around standing water, and the prolonged monsoon season hasn't helped matters.

Diseases spread by mosquitoes are a problem worldwide. The U.S. is currently facing an outbreak of Eastern Equine Encephalitis (EEE), particularly in the northeastern region of the country. So far, 11 people in the U.S. have died this year of EEE.

People infected with EEE may experience fever, headache, and chills. But if the virus makes its way to the central nervous system, it can cause encephalitis, a swelling of the brain. There is no cure for EEE.

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Disease carrying mosquitoes are responsible for an increase in humans contracting potentially deadly infections. Getty

One of the reasons for the sudden upswing in mosquito-borne illnesses could be climate change. State epidemiologist Catherine Brown of the Massachusetts Department of Public Health says, "One of the reasons we're seeing outbreak cycles more frequently is probably related to the fact that the mosquito breeding season is longer now."

The American Mosquito Control Association says EEE can be transmitted to humans and horses via the bite of an infected mosquito, but humans cannot transmit it to each other. A vaccine for the disease is available for horse, but none exists for humans.

Wider spread is West Nile virus. Mosquitoes infected with West Nile virus have been found in 46 states and the District of Columbia, according to the Centers for Disease Prevention and Control (CDC).

While most people show no sign of the disease after their initial infection, approximately one out of five people develop a fever, headache and body aches, among other symptoms. While many people with that level of infection recover completely, fatigue can last for weeks.

About one in 150 develop a more serious malady such as encephalitis or meningitis, an inflammation of the membranes around the spinal cord or brain. While recovery is possible, it may take weeks or months. Damage to the central nervous system may be permanent.

Authorities around the world are using aerial spraying in areas found to have infected mosquitos in an attempt to halt the spread of the diseases, but that is only part of a wider solution.

The CDC recommends getting rid of potential mosquito habitats, staying inside air-conditioned or screened-in areas and wearing protective clothing and using insect repellents approved by the Environmental Protection Agency to reduce the risk of being bitten.