Mosquitoes, the tiny pests that Houston residents are more than accustomed to buzzing around and being micro-sized nuisances, are packing a heavier punch this summer season.
According to Harris County Public Health, West Nile — a virus transmitted by Culex mosquitoes — is rising. There have been 74 confirmed cases of the arbovirus detected in Harris County, two dozen more cases this year than the total number of cases reported in 2023.
Dr. Peter Hotez, co-director of the Texas Children’s Hospital Center for Vaccine Development and dean of the National School of Tropical Medicine at Baylor College of Medicine, said mosquito-borne illnesses may not be the only threat to those wanting to enjoy the outdoors this summer.
Hotez noted that other arboviruses — infections caused by certain arthropods — such as tick-borne illnesses, could also increase in number over the summer months because of environmental conditions.
Hotez is also closely monitoring the potential rise of other mosquito-borne illnesses, such as Zika, Chikungunya and Dengue. All of these are transmitted by Aedes mosquitoes, which are different from the mosquitoes carrying West Nile.
“With the much warmer summers that we’ve been having and all the rainfall, I’m kind of holding my breath,” Hotez said.
“We seem to be better prepared to do mosquito control for [West Nile] as opposed to the Aedes mosquitoes where you have to go into individual homes and turn over containers containing water,” Hotez added. “It’s much more intrusive and not as well received. So, it tends to be more problematic using conventional control methods.
Culex mosquitoes—West Nile carriers—can be effectively managed by trucks that spray insecticide in the evening hours. This practice occurs in most cities and counties where the virus is detected.
As Hotez mentioned, Aedes mosquitoes are more difficult to ward off. However, he noted that there are new technologies, such as using genetically modified mosquitoes or Wolbachia technology — a type of bacteria that lives in a mosquito and is a biological control agent that reduces a mosquito’s fitness for transmitting viruses.
Hotez said Houston is a hotbed for arboviruses, and the factors that drive these illnesses to spread include warming temperatures, increased rainfall patterns, urbanization and poverty.
He advised residents to use bug spray with DEET, a common ingredient in insect repellent, and avoid going outdoors for prolonged periods in the evening.
Protection against these viruses is important as West Nile can produce severe encephalitis — inflammation of the brain — in adults and children, chronic renal illness and symptoms akin to long COVID in terms of depression and long-term neurocognitive symptoms.
Unfortunately, Hotez noted that with the increasingly higher temperatures, the spread of West Nile and potentially other arboviruses is expected to get worse in July and August before it gets better.
This article appears in Jan 1 – Dec 31, 2024.
