Mosquitoes, the itching and biting pests of summer, want their next meal to be you. But there are ways to combat them, according to county health officials, master naturalists and the CDC.
Prevention is key in avoiding mosquitoes.
“A mosquito’s life-cycle has four stages: egg, larva, pupa and adult. All mosquitoes need water to breed and spend their larval and pupal stages in water,” the Texas state health services department says in its mosquito fact sheet.
That means after rain like this week’s or rain from a hurricane, empty or remove from homes, yards and patios anything with stagant water, said Martha Marquez, a public information officer for Harris County Public Health. That includes, but isn’t limited to, flower pots, birdbaths, water bowls for pets, empty tires and toys.
“The number of mosquitoes increases during the hurricane season because the hot, humid environment provides an ideal breeding ground,” Marquez said.
Mosquito borne illnesses
The greater Houston area and Harris County has up to 56 different species of mosquitoes, according to county data, though only a few species of mosquitoes carry serious diseases like West Nile virus and Zika.
The Culex mosquito is most active at dawn and dusk and can spread West Nile, Marquez said.
Tips for avoiding, combatting mosquitoes
Use bug repellant when outdoors
Wear long pants and sleeves if possible
Install or repair screens and windows
Report dead birds to authorities because they might be a sign of West Nile Virus
Empty standing water
Mow tall grass and weeds
Cut back vines and shrubs
Change out stagnant water in bird baths and dog dishes
Dusk and dawn are the most active mosquito times, so stay indoors when possible.
For more information: https://www.dps.texas.gov/dem/Preparedness/tips/westNile.htm
Sources: Centers for Disease Control and Prevention, Texas A&M Agrilife Extension, Texas Master Naturalists
So far this season, mosquito samples carrying the West Nile virus were confirmed in traps in nine areas of the city, she said. Night-time spraying has begun in those areas, health officials said last week. And after Hurricane Harvey last year, the Texas Department of State Health Services sprayed areas because of the increased number of mosquitoes.
According to the Centers for Disease Control and Prevention, only 1 out of every 5 people infected with West Nile virus display symptoms which include headache, body ache, joint pain, vomiting, diarrhea, and a rash.
Another potentially dangerous vector is the Aedes mosquito species which can spread the Zika Virus, Yellow Fever, Chikungunya, and Dengue.
Common symptoms of Zika are fever, rash, and joint pain that last anywhere from a few days to a couple of weeks. Zika is especially dangerous for expectant mothers who may pass the infection on to their fetus. Chikungunya virus is originally from the Caribbean and generally not fatal, but causes fever, rash, joint pain, headaches, muscleaches, within three to seven days of being infected. Dengue is the leading cause of death in the tropics and sub-tropics. Its symptoms include high fever, headache, rash, muscle pain, and mild bleeding.
What to do
When going outdoors, Marquez and others suggest people use insect repellent which is registered by the Environmental Protection Agency and recommended by the Centers for Disease Control and Prevention. The repellent should contain ingredients like DEET, picaridin, or oil of lemon eucalyptus, which have proven to be highly effective when the repellent is applied correctly.
Some people swear by citronella candles, others hold fast to their Avon Skin So Soft bath oil. But there are some specific steps to take to prevent mosquitoes from breeding and then biting.
According to the Texas Master Naturalists, “yellow ‘bug’ lights,” nesting barn swallows, and certain insects can help reduce the number of mosquitoes. Additionally, the master naturalists recommend BTi, a bacterium found in soil, to treat standing water that cannot be drained, according to a naturalist blog post by Mary Anne Melton.
John Bell, an entomologist at TruGreen, said that the Aedes species can be identified by its zebra-like, black-and-white striped pattern. However, he advises that people focus on general protective measures because different species of mosquitoes can be difficult to identify.
It’s also helpful, Bell said, to reduce the number of harboring areas, places where mosquitoes lie in wait, around homes. After a storm, he suggests that people clean up debris and shrubbery because they can create spaces where mosquitoes hide.
This is especially true, the Texas mosquito fact sheet says, because flood-water mosquitoes “lay eggs above the waterline in ditches, ponds, tanks and other places where water collects. The eggs can remain in dry conditions for several months. After floods or heavy rains when the water level rises, the eggs hatch and in a few days produce swarms of aggressive and hungry mosquitoes. Another wave of mosquitoes occurs later, typically 10 to 14 days after the rains stop. These mosquitoes are a big nuisance.”
According to Marquez, this year the Mosquito and Vector Control Unit in Harris County had four samplings of mosquitoes in the area that tested positive for West Nile Virus. She said that the first positive test usually appears around May and the number of positives increase throughout the summer, even though the area where the positive test occurs is sprayed.
Currently, there are nine regions where mosquitoes have tested positive for West Nile Virus in the greater Houston area with a total of 10 positive tests as of Tuesday.