The late summer-early fall heatwave baking the region could translate to an increase in West Nile virus cases.
As a result, officials at the San Joaquin County Mosquito and Vector Control District are asking residents to remain vigilant in protecting themselves against mosquitoes and reporting dead birds they find, which could be infected with the disease.
Also, a few weeks ago, the District’s mosquito-borne disease surveillance program discovered St. Louis Encephalitis virus (SLE) in a group of collected mosquitoes found in a rural area of the county. Two different mosquitoes in two traps tested positive, with the traps located south of Lockeford and east of Lodi.
“This is the first find of St. Louis Encephalitis in San Joaquin County since a human case identified in 1973,” said Aaron Devencenzi, Public Information Officer of the District.
The SLE virus is in the same family of flavivirus as West Nile virus. Over recent years SLE has been detected in several areas of California.
“With this finding, it is important that people remove standing water around homes and protect themselves from mosquito bites. Mosquito prevention is everyone’s responsibility,” said Devencenzi.
Also, the District still offers mosquitofish, free of charge, and will deliver them to local residents for use in neglected or abandoned pools, animal water troughs, ornamental ponds and more.
“Our front office remains closed to the public due to COVID-19 so we will deliver them,” Devencenzi said.
Residents who want mosquitofish for use on their property can contact the District at 209-982-4675. Ground and aerial spraying continues in the area as well, with multiple reports of WNV-positive mosquitoes so far this season.
“At this time we would hopefully be trending downward but with this heatwave, it will cause a heightened alert,” Devencenzi explained. “It’s real likely that we’ll see West Nile virus continue to be fairly strong.”
The District will also continue monitoring and testing mosquitoes for SLE, officials added. Similar to West Nile virus (WNV), birds are the reservoir host once exposed to a mosquito with SLE. Humans are a dead-end host, unable to infect other humans through casual contact. Symptoms are also similar to WNV. Additional information on symptoms and mortality rates associated with SLE are found at the California Department of Public Health or the Center for Diseases Control websites. Currently, WNV is very active in the mosquito population throughout San Joaquin County.
With the recent high temperatures, the mosquito life cycle speeds up, and so does the replication of the virus within their bodies. Therefore, people must protect themselves from mosquito bites. Take these precautions to reduce the risk of WNV infection and other mosquito-transmitted diseases:
Eliminate all sources of standing water on your property.
According to label instructions, when outdoors, apply insect repellent containing EPA-registered active ingredients, including DEET, Picaridin, oil of lemon eucalyptus, or IR3535. Repellents keep mosquitoes from biting people.
Avoid spending time outside when mosquitoes are most active, at dawn and dusk, and especially for the first two hours after sunset.
When outdoors in cooler weather, wear long pants, loose-fitting long-sleeved shirts, and other protective clothing.
Exclude mosquitoes from your home with tight-fitting screens on doors and windows.
Contact your veterinarian for information on vaccinating equine against WNV.
Report daytime biting mosquitoes or significant mosquito infestations to San Joaquin County Mosquito & Vector Control District at www.sjmosquito.org, (209) 982-4675, 1-800-300-4675.
Report dead birds to 1-877-WNV-BIRD (1-877-968-2473) or www.westnile.ca.gov.
For additional information, request service, or to sign up for the District’s spray notification system, go to www.sjmosquito.org or call (209) 982-4675. Follow them on Facebook @SJmosquitoandvector for tips and informative posts.
Escalon resident Gary Haskin currently serves as vice president of the District’s Board of Trustees.