Around the World: Mosquito-borne Illnesses

In recent months, it has been difficult to go even a day without hearing about the mosquito-borne Zika virus in the news. The media has focused much of its attention on the risk of potential birth defects that may result if a pregnant woman becomes infected. Though Zika virus may be the only mosquito-borne disease currently in the spotlight, it is certainly not the only one that can cause concern.

While many may consider mosquitoes to be no more than annoying pests, they have the potential to be dangerous. In fact, illnesses spread through mosquitoes account for millions of deaths each year. In addition to Zika virus, mosquitoes can spread these viruses:

• West Nile — About 20 of every 100 people infected with West Nile may develop symptoms of severe disease, including high fever, neck stiffness, disorientation and stupor, coma, tremors, convulsions, muscle weakness and paralysis. Infections occur on five continents.
• Malaria — This disease is actually transmitted by a parasite that is found in mosquitoes. Severe disease is almost always fatal without treatment. Symptoms can include fever, headache, chills and vomiting. Vaccines and medications to prevent malaria are available, but unfortunately, each year cases of malaria occur in about 95 countries throughout the world.
• Dengue — Flu-like symptoms can develop into severe infection with symptoms including drop in body temperature, severe abdominal pain, persistent vomiting and fatigue. There is no treatment for dengue, which makes early detection and medical care critical to survival. Dengue is a leading cause of severe illness and death among children in some Asian and South American countries.
• Yellow fever — Symptoms include fever, muscle pain, headache, shivers, nausea and vomiting, but about 15 of 100 people infected experience a second, more toxic phase. This phase includes high fever, jaundice, bleeding from mouth, nose, eyes and stomach, and decreased kidney function. About half of these patients die within 10 – 14 days. An effective yellow fever vaccine exists, but is not routinely recommended in the U.S. However, in some countries, travelers are required to show proof of vaccination before they can enter the country.
• Chikungunya — Symptoms include fever and severe joint and muscle pain, but are often mild. The infection may be undiagnosed or misdiagnosed in areas where dengue is also prevalent. Serious complications are not common, but can include arthritic pains and death in older people. Chikungunya occurs in more than 60 countries in Asia, Africa, Europe and the Americas.

Generally, transmission of mosquito-borne illness occurs when a mosquito sucks blood from an infected host and injects it into a new host. In some cases, infected people can also transmit the infection to other humans, such as Zika virus, which has also been found to be transmitted by sexual contact.

The best way to protect yourself against any of these infections is to prevent mosquito bites. Recommendations include:

• Using insect repellents with one of the following active ingredients:
  • DEET
  • Picaridin (also known as KBR 3023, Bayrepel® and icaridin)
  • Oil of lemon eucalyptus (OLE)
  • Para-menthane-diol (PMD)
  • IR3535
• Wearing clothing that covers the skin
• Using nets when sleeping or resting

The World Health Organization recently produced an interactive, tile board related to mosquito-borne illnesses. Check it out today to learn more about these illnesses.

Additional resources

• CDC — Preventing mosquito bites
• EPA — Insect repellents
• EPA — Using repellent products to protect against mosquito-borne illnesses
• CHOP Health Tip of the Week — Zika Update: Situation in Florida, Protecting Yourself