First case of chikungunya virus in Fresno County reported

Fresno County health officials warned Friday to be extra alert to mosquito bites as the first case of chikungunya virus has been diagnosed in a woman who was bitten by a mosquito while on vacation in another country.

The woman, who was not identified, was not hospitalized.

Health officials are concerned about the spread of the virus in the Valley because Aedes aegypti, a type of mosquito that can transmit the virus, has been found in Clovis, parts of Fresno, Madera, Exeter and Arvin.

In addition to being able to transmit chikungunya, the mosquito also can infect people with dengue and yellow fever. The tropical diseases have symptoms that include fever, severe headaches and body aches.

The day-biting mosquito was first found in Clovis and Madera in 2013 and has now been captured in southeast Fresno, Exeter and in Arvin in Kern County. Worldwide, the A. aegypti mosquito population has exploded in the Western hemisphere, said Steve Mulligan, manager of the Consolidated Mosquito Abatement District, which serves Clovis and parts of Fresno.

“At the end of 2013, it came into the Caribbean area and in 2014, we’ve had 1 million cases in the Western hemisphere,” he said.

Mexico is having an epidemic of chikungunya virus, Mulligan said. “We’re going to have more people coming back with disease, and there’s a potential, if they come back and are bitten by this type of mosquito, then that mosquito could be infected and could infect others,” he said.

Valley doctors need to inquire about recent travel history for patients who have flu-like symptoms and severe joint pain, said Dr. David Bird, health officer for the Fresno County Department of Public Health. The virus got its name, chikungunya, from an African term that means to bend over, “because you’re so contorted in pain,” Bird said. Joint pain from the infection typically lasts for a week to 10 days, but lesser pain can linger for months, he said.

To prevent the spread of the virus, it’s important for anyone infected with chikungunya to protect from further mosquito bites for 21 days after symptoms of the virus first appear, said David Luchini, assistant director of the health department.

Besides the concern of mosquito bites causing chikungunya virus, other mosquitoes in the Valley can transmit West Nile virus, which can cause mild flu-like symptoms to severe neurological disease. Last year, 29 Californians died of neurological complications from West Nile virus and 798 were infected. The Valley had no deaths, but 53 people in Fresno County were infected and 21 were infected in Tulare County. Kings County had five infections and Madera County had one.

Bottom line, people need to protect themselves from mosquito bites. The A. aegypti bites during day hours and the West Nile carrying mosquitoes bite more at dawn and dusk.

Water sources in backyards, such as pet watering bowls, should be emptied, rinsed out and refilled twice weekly, Mulligan said. Neglected swimming pools should be reported to mosquito control agencies.

Bird had this advice: Wear long sleeves or pants when mosquitoes are present or use insect repellants that contain DEET, picaridin, oil of lemon eucalyptus or IR 3535, according to label instructions.

And the doctor said, “Check windows and screen doors for any possible mosquito entry and repair those.”

This story was originally published June 26, 2015 at 3:12 PM with the headline "First case of chikungunya virus in Fresno County reported."