Residents Urged to Empty Stagnant Water

‘Tis the season to drain water.

As a very wet rainy season draws to a close, stagnant water should be cleared to prevent mosquitos from breeding and spreading West Nile virus, public health officials warn.

Pools ought to be maintained with working pumps, standing water in flower pot trays emptied and yard vegetation trimmed to curb mosquito growth. Residents can secure window screening over barrels used for collecting rainwater to prevent the flying insects from laying eggs on the liquid surface.

“The water can still go in the barrel but the mosquitos can’t get in,” said Lamar Rush, Vector Control program supervisor for the Long Beach Department of Health and Human Services Bureau of Environmental Health.

Rush said mosquitos die down during the winter but emerge when spring starts. Rush said traps are placed throughout the city to see how many mosquitos are in an area.

“If there’s only five or six, then everything is fine,” he said. “If it jumps up to 100 or something, you have to find out where they are breeding at.”

Vector Control uses two primary methods for controlling mosquito populations, he said. Gambusia fish are released into ponds to eat mosquito larvae. The fish are small like guppies, he said.

And natural bacterium for killing mosquito larvae is used for stagnant water in other cases. The bacterium (Bti) only targets mosquito, blackfly and fungus gnat larvae and is harmless to other creatures, according to the EPA.

A third fogger method is rarely used.

“We’ve already started doing our surveillance work putting out traps,” Rush said. “We’ve already started treating drains with the bacteria in our breeding sites that we know exist, that actually breed mosquitos.”

A mosquito presence is confirmed before any eradication takes place.

“We don’t treat unless we know there are mosquitos there,” he said. “We always put traps out first. That’s the method.”

Captured mosquitos are sent to a state lab and analyzed for mosquito-borne diseases including West Nile and St. Louis encephalitis.

Chickens also are used to monitor West Nile, as they do not die from the virus.

Four chicken coops exist in the outskirts of the city, each with 10 sentinel chickens. A small amount of blood is drawn from them every two weeks to check for West Nile and other mosquito diseases. West Nile antibodies show up in the blood of an infected chicken, indicating a mosquito with West Nile bit it.

Rush said the chickens are checked on once a week to ensure they have enough food and water.

In addition, dead crows are used for West Nile surveillance. After a person calls-in a dead crow to Animal Control, the bird is then sent to the state lab to see if it died from West Nile, Rush said.

In the past five years Long Beach had a total of 77 West Nile cases in humans; two in 2012 with no deaths, seven in 2013 with one death, 53 in 2014 with three deaths, 11 in 2015 with no deaths, four last year with no deaths and none so far this year, reported Long Beach Director of Environmental Health, Nelson Kerr.

Regarding testing of mosquitos, chickens and birds for mosquito-borne diseases, Kerr said through email that Long Beach had one West Nile-positive mosquito sample last year, three positive chickens and zero positive birds.

For California, 30 counties were positive for West Nile last year with 442 human cases, 1,352 dead birds, 3,528 mosquito samples and 343 sentinel chickens, according to the state’s website westnile.ca.gov.

Los Angeles County had by far the most human cases last year at 151. Orange County was the second highest with 32.

Long Beach Health Officer Anissa Davis explained the symptoms of West Nile virus:

“Most people who become infected with WNV will not become sick, or will only have mild symptoms, including fever, headache, nausea, and rash. In very rare cases, people will develop severe disease, which can lead to paralysis or death. There is no treatment for WNV,” she said through email.

“If residents believe they are experiencing symptoms of West Nile virus, they should consult with a healthcare provider for evaluation and diagnosis,” she added.

Dr. Davis wrote, “With the concern of mosquito borne diseases such as WNV and Zika virus, it is important to protect yourself and your loved ones by using mosquito repellent such as DEET and removing standing water around your home. Mosquitos can breed in small amounts of water, so it is important to eliminate possible breeding grounds by dumping or draining anything capable of holding water for more than a few days, such as buckets, potted plants or fountains.”

kirt@beachcomber.news