KTLA

L.A. County could see more mosquitoes with hotter, longer summers

While many people might think mosquitoes are not a big deal in Southern California, where it’s not so humid, they should think again.

Public health officials say that the number of mosquito bites in the Los Angeles area has risen in recent years. And the hotter summers of the past few years may foreshadow conditions that boost the numbers of these small, blood-sucking pests.


That raises concerns about West Nile Virus, an incurable and potentially deadly mosquito-borne illness that can be transmitted to humans and animals.

L.A. County health officials on Monday reported this year’s first death linked to West Nile virus in the county. In 2020, there were 93 West Nile virus cases and seven deaths, according to public health data.

Officials with the Greater Los Angeles County Vector Control District say that there are six new areas that are seeing mosquitoes that have tested positive for the West Nile virus. Those areas include Santa Fe Springs, La Mirada, Long Beach, Paramount, Canoga Park and Winnetka.

However, Vector Control officials say that, overall, they’re seeing a relatively lower number of West Nile virus cases this year.

“I would say, relatively, this is a lower year, but it is still very important for our residents to take care,” said Anais Medina Diaz, a Vector Control District spokesperson. “West Nile virus is endemic to L.A. County.”

The virus is transmitted to people and animals through the bite of an infected mosquito. 

Most people don’t experience severe symptoms when infected, and those over 60 are at greater risk, according to the U.S. Centers for Disease Control and Prevention. Symptoms of severe illness include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis. 

While the number of West Nile virus cases has been relatively low this year, Vector Control official Susanne Kluh said that there’s been an increase in the number of daytime-biting mosquitoes capable of transmitting debilitating viruses.

The Aedes aegypti species, which are distinguished by their black and white stripes, can transmit dengue, chikungunya and yellow fever — viruses that can cause painful symptoms including headache and high fever, officials said.

“The good news is that currently, we have not seen any evidence that these invasive mosquitoes are spreading any disease,” Kluh said.

However, Kluh said the Aedes aegypti species is hard to control and they’ve become “such a big nuisance.”

“This has had a bigger impact on people’s lifestyle. It’s not just these few hours between dawn and dusk, where you have to deal with a few mosquito bites,” said Kluh. “While the common household mosquitoes do cause diseases, they should be taken seriously. But they just don’t have the same number of bites that are associated with these invasive mosquitoes.”

To help control the population of these pesky biters, Kluh said residents should try to minimize the amount of standing water sources in their yards.

“These invasive Aedes species lay individual eggs and they attach them to the containers such as little flower pots, buckets, water bottle caps, you name it, or whatever people have in their yard,” Kluh said.

To reduce mosquito populations in communities, officials advise residents to get rid of standing water in places like clogged rain gutters, rain barrels, buckets, watering troughs, and make sure swimming pools, spas, and ponds are properly maintained. Water in pet dishes, birdbaths and other small containers should be changed weekly.