Mosquitoes are among the most important insect pests affecting the health of people. They are not just annoying; they can also transmit many diseases. A rainy spring proceded by a mild winter, can lead to an active mosquito season.
Mosquitoes are present in Central Texas year-round, but the population is largest and most active from May through November. During this period, Austin Public Health monitors the population and tests for mosquito-borne viruses. Those that carry West Nile Virus (WNV) are of particular concern.
- The Austin/Travis County Arbovirus Surveillance Map (PDF) highlights Austin/Travis County zip codes where one or more mosquito traps test positive for West Nile Virus.
Incidence of West Nile
West Nile Virus is the most common mosquito-borne disease in the US. In 2012, there was a large outbreak of WNV with 5,674 human cases reported nationwide. In Travis County, 153 cases were reported that year, with 1,868 cases reported in Texas. A majority (62%) of the cases in Travis County were males; the age range was 11 to 91 years; and most (58%) were 50 years of age or older. Six people in Travis County died that year of WNV, all 60 years of age or older.
- In 2019, there were no positive mosquito pools or human cases of WNW in Travis County. There were 119 positive pools reported across Texas, with 30 human cases.
- In 2020, there have been 36 positive mosquito pools and 5 probable human cases of WNV in Travis County. There were 1,389 positive pools reported across Texas, with 69 human cases.
Most people who are infected with the West Nile Virus will not get sick. However, it is estimated that 20% of people who become infected will develop West Nile fever with mild flu-like symptoms, including fever, headache and body aches, a skin rash on the trunk of the body, and swollen lymph glands.
About one in 150 people infected with WNV will develop severe illness. Those older than 50 are at higher risk for severe disease. The severe symptoms can include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness, and paralysis.
Symptoms can last for as short as a few days, or may last several weeks, and neurological effects may be permanent. Read more about symptoms from the Centers for Disease Control and Prevention (CDC).
The most important way to prevent WNV is to reduce the number of mosquitos where people work and play. Mosquitoes can only breed in standing water, and it can be in as little as one teaspoon. By draining all sources of standing water in and around your property, you reduce the number of places mosquitoes can lay their eggs and breed.
Using insect repellents and wearing protective clothing is the best way to prevent getting bitten by mosquitoes.
Fight the Bite Day and Night with the Four Ds:
- Dusk through dawn Although different species of mosquitos are active at different times of day, the species that spread West Nile Virus are most active between dusk and dawn.
- Dress: Wear pants and long sleeves when you are outside. Wear light-colored, loose-fitting clothing; mosquito repellent clothing is also available
- DEET: Apply insect repellent that contains DEET. Read and follow label instructions. Spray both exposed skin and clothing with repellent.
- Drain: Get rid of standing water in your yard and neighborhood. Old tires, flowerpots, clogged rain gutters, birdbaths and wading pools can be breeding sites for mosquitos.
Ways to eliminate mosquito breeding sites:
- Reduce standing water around your home and neighborhood (including plant saucers, toys, buckets, and clogged gutters)
- Replace water at least once a week in pet dishes and birdbaths
- Repair leaky faucets and pipes
- Keep window and door screens in good repair
- Carefully screen rainwater harvesting cisterns to exclude mosquitos
- Use “mosquito dunks” (Bacillus thuringiensis israeliensis) to reduce mosquitos in rain barrels and permanent bodies of water. These products slowly release a biological larvicide that kills the pest
- Austin Public Health Environmental Vector (Mosquito) Control Program
- Earth Wise Guide to Mosquitos
- West Nile Virus: What you need to know, (Center for Disease Control and Prevention)
- West Nile Virus in Texas (Texas Department of State Health Services)
- Mosquitos and the Diseases They Transmit (Texas Cooperative Extension Service)
- To report a mosquito problem, call 3-1-1 or complete a Service Request online.