Phoenix Area Sees Spike In Number Of West Nile-Infected Mosquitoes

While the mosquitoes remain due to a wet winter and cool spring, they seem to be carrying more diseases this year, like West Nile virus.

“Some people will only have flu-like symptoms, and may not even know they have West Nile virus or St. Louis encephalitis. But what we’re really concerned with is those who come down with the neuroinvasive, so they’ll have encephalitis or meningitis or neurological issues and possibly even fatal,” said Steve Young, a Maricopa County Environmental Services Department vector lab technologist.

Each day, Young and his team collect mosquitoes from traps around the Valley and tests them for diseases.


At this time, a record number of mosquitoes are testing positive.

“A lot higher, like a lot lot higher,” said Young.

So far this year, they’ve discovered nearly 220 mosquitoes carrying West Nile, and 102 more with St. Louis encephalitis.

It’s almost the same level as all of 2018 and it’s only June.

“And if the trend keeps going all the way into the monsoons, that’s a pretty scary idea too. So if we’re starting this far ahead of schedule and it’s not even monsoon time yet, that’s potentially a powder keg,” said Young.

The County vector lab thinks we will see the highest number of infected mosquitoes in the last 10 years.

“It does indicate that there’s probably a higher risk of being exposed to the virus,” said Young.

Two people have already been diagnosed with West Nile in Maricopa County.

The County has been fogging problem neighborhoods in an attempt to fight it. And they say it’s more important than ever to drain any standing water and wear protective clothes and bug spray while you’re outside.

“It only takes one mosquito bite and then you’re exposed to virus,” said Young.

Taking extra precautions such as wearing clothes that cover skin and using bug spray is recommended.