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The post-monsoon squadrons of mosquitoes attacking your ankles are just extremely annoying, not deadly. You'll have to wait a bit longer for that.

The current swarms of highly-aggressive mosquitoes - often referred to as "ankle-biters" - are "incompetent vector mosquitoes," says Patti Woodcock, spokeswoman for the Pima County Health Department. They don't carry West Nile Virus, at least not here.

Woodcock said that while the ankle-biters are shooting blanks in Southern Arizona, they sometimes carry deadly diseases elsewhere. She doesn't know why.

But while we ponder that bit of good luck, Woodcock and other mosquito program officials and experts expect that the two Culex mosquito varieties that do carry West Nile Virus may be breeding like fiends.

Typically, local and state officials say, West Nile doesn't start to show up until late August or into September.

Last year there were three deaths and 46 confirmed cases of West Nile Virus in Pima County, but only one human case was confirmed by this date. Statewide there were 143 confirmed cases.

To date, Woodcock said, Pima County has only had one dead bird - a thrush found near Prince and County Club roads - test positive for West Nile Virus, and no humans.

It may take the West Nile Virus carrying mosquitoes longer to build up a population, said University of Arizona entomologist Elizabeth Willott.

She said the ankle biters can go from egg to pupal stage in six days, but the Culex variety take a week or more.

"That might be all it takes," said Willott, "but that's just speculation."

Then again, she wonders if the delay in their emergence might be due to the streaks of high temperatures, which may make the breeding water too hot to survive.

The message in all the uncertainty, Woodcock said, is that we're far from over the hump.

Not everyone has been lucky. Craig Levy, an epidemiologist with the Arizona Department of Health Services said there have been 18 people in Maricopa County and one person in Pinal County who have tested positive for West Nile Virus.

"When it does show up," Levy said, "it sometimes shows up with a vengeance."

But Levy isn't jumping to conclusions. He, too, says there are many things that aren't understood about mosquitoes and how they spread disease.

And some of what is known, Levy said, is counterintuitive.

For instance, he said heavy rains can actually slow the mosquito population growth.

"Rains flush out storm drains, (but) then they start breeding successfully again," Levy said.

And while positive cases popped up earlier than usual, at least in other parts of the state, Levy said reports have been tapering off.

"This year we don't know what to expect," Levy said.

City and county crews are aggressively treating standing water, Woodcock said, and public education efforts are going strong.

One of the education efforts is the Midtown Mosquito Pilot Project, being run out of the Tucson Botanical Garden, on North Alvernon near East Grant Road.

University of Arizona entomologists are monitoring mosquito traps there and project workers have gone through the adjacent neighborhood knocking on doors and passing out information.

"There's a real misconception in the public that plants are breeding mosquitoes," said Nancy Laney, the gardens' executive director.

Aside from saucers that may collect overflow from flower pots, Laney said plants are not a problem. "Plants can often help with mosquito problems because they help water infiltrate (into the ground). It's not producing mosquitoes."

Laney said she became aware of the misconception while listening to an audience members at a public meeting.

"Someone said, ‘I've completely bladed my whole yard, and I'm still having (mosquito) problems,' " Laney said.

"We don't want people to think they've got to have a bare yard to get rid of mosquitoes."

The most common problem program workers have seen while visiting the gardens' neighbors is from plastic kiddy pools and toys left in backyards collecting water - particularly those left behind walls where they are out of sight and forgotten, Laney said.

Meanwhile, at the University of Arizona, a College of Agriculture entomologist is evaluating treatments for standing water.

There are products that work to varying degrees to inhibit growth of mosquitoes in standing water, said UA entomologist Tim Dennehy.

"Mosquito dunks work marvelously," Dennehy said, but only to inhibit mosquitoes before their later stages.

He said the testing results are just preliminary and won't be published until next year.

So far, he said, vegetable oils advertised for treating standing water don't seem to work.

But some petroleum-based oils are effective.

Bleach was not found to be effective.

Common rumored fixes, such as apple cider vinegar and hydrogen peroxide, don't seem to work.

But he said one "folk" cure that does work surprisingly well is dish washing soap - at least the two brands they tested: Sunlight Ultra Lemon Citrus Burst and Trader Joe's Seventh Generation brand.

However, Dennehy said they had not yet worked out the concentrations required and that it had to be a balance between too little and enough to create "a bubble bath."