Health officials reported another new case of human West Nile Virus in San Joaquin County this past week – neighboring Stanislaus reported five – and officials are reminding residents to continue to take precautions against mosquitoes that can carry the illness.
“This year we have seen an overall higher population of mosquitoes than last year and also a higher population than the five-year average throughout the entire county,” noted San Joaquin County Mosquito and Vector Control District spokesman Aaron Devencenzi.
Both the Escalon and Farmington areas have had mosquito samples test positive for WNV in the past week and the region has had both ground and aerial spraying in an effort to contain the population.
And even as the weather starts to cool, Devencenzi said the fluctuation in temperatures – into the 90s one day, dropping to the 70s the next – can lead to more mosquitoes.
“People still need to take precautions,” he said, noting that prevention with insect repellent, limiting standing water on your property and wearing long sleeves can help residents protect themselves.
The mosquito ‘season,’ he added, typically runs through November in San Joaquin County.
Some are pasture mosquitoes that are more of a nuisance but don’t carry the disease, others are those that have West Nile and can pass it on to humans.
“Each year West Nile Virus tends to be more prevalent in some areas than others, that changes year to year,” he added, noting that Escalon and Farmington have had multiple samples test positive over the last couple of months.
“This is something we are continuing to monitor, continuing to treat,” he said.
Officials have also reported one horse being diagnosed with West Nile.
The horse survived, said Devencenzi, and there have also been confirmed cases of 16 birds testing positive for WNV this year.
“Fortunately this year we have had less human cases than last year,” he added.
Traps to collect mosquitoes are put out on Mondays, with testing of the samples done on Tuesdays, with a decision then made on Wednesdays whether to do spraying if positive samples are found.
Across the state, noted San Joaquin County Public Health Department spokeswoman Krista Dommer, there were 44 new human cases of West Nile reported last week. The highest number, 12, was in Los Angeles County. Fresno County (3) and Ventura County (1) reported their first cases of the year.