MOSQUITO BORNE ILLNESSES

Mosquito Borne Illnesses: Information and Prevention

Zika Virus

Zika virus is primarily spread to people through mosquito bites. Approximately 80% of people infected with the virus do not become ill. For those who do develop symptoms, illness is generally mild and typically lasts a few days to a week. The most common symptoms of Zika virus disease are fever, rash, joint pain, and conjunctivitis (red eyes). Mosquitoes that spread Zika virus are aggressive daytime biters.

Zika virus is a new, emerging threat and the City’s response will be adapted to address the changing needs with guidance from Tarrant County Public Health, Texas Department of State Health Services, and Centers for Disease Control and Prevention.

West Nile Virus

West Nile Virus (WNV) is a mosquito borne virus that can infect humans, birds, horses and other mammals. You can reduce your risk of being infected with WNV by using insect repellent and wearing protective clothing to prevent mosquito bites. There are no medications to treat or vaccines to prevent WNV infection. Fortunately, most people infected with WNV will have no symptoms. About 1 in 5 people who are infected will develop a fever with other symptoms. Less than 1% of infected people develop a serious, sometimes fatal, neurologic illness.

What Are The Symptoms Of The West Nile Virus?

Most people who are infected with WNV either have no symptoms (80%) or experience a mild or moderate illness with symptoms such as fever, headache, fatigue, or body aches before fully recovering. It is estimated that 20% of people who become infected with WNV will develop West Nile Fever. Of these, 1/150 persons may develop the more serious neuroinvasive West Nile.

Some persons may also develop a rash or swollen lymph glands. In some individuals, particularly persons 50 years of age and older, WNV can cause serious brain and spinal tissue damage. Severe illness may include encephalitis (inflammation of the brain), meningitis (inflammation of the membrane around the brain and spinal cord), or acute flaccid paralysis (a polio-like syndrome in which muscles become very weak or paralyzed). Other severe symptoms may include headache, high fever, stiff neck, nausea and vomiting, confusion, coma, tremors, convulsions, muscle weakness and/or paralysis. At its most serious, WNV can cause permanent neurological damage and death. Among those people who need to be hospitalized for WNV, 10-15% die of their illness. People who do develop symptoms normally become ill 3-15 days following the bite of an infected mosquito.

How Is West Nile Virus Spread?

Infected Mosquitoes. Most often, WNV is spread by the bite of an infected mosquito. Mosquitoes become infected when they feed on infected birds. Infected mosquitoes can then spread WNV to humans and other animals when they bite.
Transfusions, Transplants, and Mother-to-Child. In a very small number of cases, WNV also has been spread through blood transfusions, organ transplants, breastfeeding and even during pregnancy from mother to baby.
Not through touching. WNV is not spread through casual contact such as touching or kissing a person with the virus.

^{Can you get West Nile Virus directly from birds?}

There is no evidence that a person can get the virus from handling live or dead infected birds. However, persons should avoid bare-handed contact when handling any dead animals and use gloves or double plastic bags to place the carcass in a garbage can.

How is West Nile Virus treated?

There is no specific treatment for WNV. Most people who become infected will get better on their own. In more severe cases, intensive supportive therapy is indicated, i.e., hospitalization, intravenous (IV) fluids and nutrition, airway management, ventilator support if needed, prevention of secondary infections and proper nursing care.

How long does it take to get sick if bitten by an infected mosquito?

Most people who are infected with WNV have no symptoms or experience only mild illness. If illness does occur, symptoms generally appear between 3 to 15 days of being bitten by an infected mosquito.

Chikungunya Virus

Chikungunya virus is transmitted to people by mosquitoes. The most common symptoms of Chikungunya virus infection are fever and joint pain. Other symptoms may include headache, muscle pain, joint swelling, or rash. In late 2013, Chikungunya virus was found for the first time in the Americas on islands in the Caribbean. There is a risk that the virus will be imported to new areas by infected travelers. There is no vaccine to prevent or medicine to treat Chikungunya virus infection. Travelers can protect themselves by preventing mosquito bites. When traveling to countries with Chikungunya virus, use insect repellent, wear long sleeves and pants, and stay in places with air conditioning or that use window and door screens. Mosquitoes that spread Chikungunya virus are aggressive daytime biters.

How can I reduce the chance of getting mosquito borne illnesses?

Avoid getting bitten by mosquitoes! No amount of mosquito control can completely prevent diseases associated with mosquitoes. Taking simple precautions makes a big difference in the likelihood of getting WNV or other mosquito transmitted diseases.Remember the 3 D’s:

Dress in long sleeves and pants when you’re outside. For extra protection, you may want to spray thin clothing with repellent.
DEET is an ingredient to look for in your insect repellent. Follow label instructions, and always wear repellent when outdoors.
Drain standing water in your yard and neighborhood where mosquitoes can breed. This includes old tires, flowerpots, clogged rain gutters, etc. Mosquitoes may develop in any water stagnant for more than three or four days. For shallow standing water that cannot be eliminated, check regularly for the presence of mosquito larvae and if seen, apply a biological larvicide often referred to as ”mosquito dunks”, available at local hardware stores.