West Nile virus confirmed in three Harris County locations

It's that time of year again: Mosquitoes carrying the West Nile virus have shown up in traps in three areas in Harris County. It won't be long until people start being infected. It's that time of year again: Mosquitoes carrying the West Nile virus have shown up in traps in three areas in Harris County. It won't be long until people start being infected. Photo: LUIS ROBAYO, AFP/Getty Images Photo: LUIS ROBAYO, AFP/Getty Images Image 1 of / 60 Caption Close West Nile virus confirmed in three Harris County locations 1 / 60 Back to Gallery

In what marks the start of the West Nile season, mosquitoes have tested positive for the virus in three locations in Harris County, public health officials reported Monday.

In the past two weeks, mosquito samples carrying the West Nile virus were confirmed in traps in the 77338 ZIP code in the northeast, the 77087 ZIP code in the southeast and the 77026 ZIP code around the Kashmere Gardens area northeast of downtown. Night-time spraying has begun in those areas.

The first of the confirmations was made May 25, the month West Nile often starts showing up in Harris County mosquito traps. Confirmation of mosquitoes infecting people typically follows around July.

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There were 15 human cases of West Nile in Houston and Harris County in 2017.

The West Nile virus first arrived in Texas in 2002. Most people infected have no symptoms, but it causes flu-like symptoms, including fever, headache, vomiting and rash in some people and has proved fatal in a small percentage of cases. A 2012 Baylor College of Medicine study found it also can cause chronic health problems.

To prevent infection, public health officials recommend people cover up outside and wear mosquito repellent containing DEET, eliminate standing water in the yard and ensure window screens are intact.

Todd Ackerman writes about medicine for the Houston Chronicle. He can be reached at todd.ackerman@chron.com or on Twitter@ChronMed.