What you need to know about Zika

For those new to the mosquito control game, the question you’re most likely to get this summer is, “Should I be worried about Zika?”

The Zika virus is here. Don’t panic.

That’s the message the National Pest Management Association (NPMA) shared at a webinar in May called “Zika: What you should know.”

“In certain areas of the country, it simply will not be an issue,” says Cindy Mannes, vice president of public affairs for NPMA. “So, our message is to not use fear tactics and to try not to scare people.”

The last day of May brought the first reported U.S. case of a child with Zika-caused microcephaly, a birth defect linked to the virus. In another high-profile case, Francisco Rodriguez, a pitcher for the Detroit Tigers, announced June 1 that he’d battled Zika for eight months while spending the offseason at his home in Venezuela. The illness affected part of his offseason training.

In fact, Zika has been here for months. As of June 8, the Centers for Disease Control & Prevention (CDC) said 691 travel-associated cases had been reported in the U.S. The only states that haven’t had a case are Idaho, Wyoming, North Dakota and South Dakota. In U.S. territories, there had been four travel-associated cases reported and 1,301 locally acquired cases. The majority of those cases come from Puerto Rico.

The good news is the U.S. has not seen any locally acquired cases yet, meaning there is still time to control the disease in the states. The bad news is peak mosquito season is hitting now.

As mosquito control is a rising trend in the landscape industry, contractors new to the offering might not have experience fielding questions about potential outbreaks.
Here are a few questions you might be asked about the recent uptick in the Zika virus, covered during the NPMA webinar presented by researchers and professors of entomology, a member of the CDC’s Zika task force and a panel of pest management company owners.

What is Zika?

Zika is a viral disease spread primarily through the bite of an Aedes species mosquito—such as the yellow fever mosquito and the Asian tiger mosquito—that is infected with the Zika virus.

Aedes mosquitoes are the perfect contractors of diseases like Zika, says Laura Harrington, Ph.D., professor in the Department of Entomology at Cornell University.

“They have a preference for humans and are stealthy biters,” she says. “Their habitats (also) are typically in close association and contact with humans.”

By “stealthy biters,” she means the bites often aren’t felt or anticipated until after the bite. Additionally, people typically associate mosquitoes with evenings and nights, but these guys are daytime feeders.

The virus can be transmitted other, less likely ways, such as sexually and through blood transfusions. Pregnant women or women planning to become pregnant should be most concerned, says Joe Laco from the CDC’s Zika Response Team.

“Zika virus can pass from a pregnant woman to her fetus during pregnancy or around the time of birth,” he says, noting the infection in pregnancy can cause microcephaly and other brain defects. Microcephaly is a birth defect in which a baby’s head is smaller than expected when compared to babies of the same sex and age. Health officials say the virus is also likely a trigger for Guillain-Barré Syndrome (GBS), which affects a small portion of the infected. GBS is a rare illness in the nervous system in which the immune system damages the nerve cells, causing muscle weakness and other issues.

How do I know if I have it?

Zika symptoms are similar to flu symptoms. They include fever, rash, joint pain, conjunctivitis (red eyes), muscle pain and headache. Still, one in five people with the disease won’t show symptoms, the CDC says, though it’s in the blood stream for up to a week. Cases are often diagnosed through blood tests.

“Many people infected with Zika virus won’t even know they have the disease because they won’t have symptoms,” says Laco. “For those who do have symptoms, they are (typically) mild and last for several days to a week.”

Right now, there is no medicine or vaccine that treats the Zika virus. The CDC suggests infected people treat the symptoms with rest, acetaminophen to reduce fever and pain, and fluids to prevent dehydration. The NPMA reminds lawn and pest professionals they may be an authority on mosquito biology and control, but they are not doctors.

“We’re mosquito experts; we’re not disease experts,” Mannes says. “So it’s really important to talk about mosquito control, not the disease itself. For the disease itself, (clients) really need to talk to the CDC or the departments of health. That’s their expertise.”

What does a pest management professional do to prevent it?

Unfortunately, pest management professionals cannot eliminate the spread of a disease like Zika—but they can help prevent it. The first and most important step is managing that expectation with the client.

“When a client hires a firm, the initial expectation is that they will have no more mosquitoes, no more bites, and that’s really difficult to do because when we’re dealing with mosquito control it’s in an outdoor environment,” says Jim Fredricks, Ph.D., vice president of technical and regulatory affairs for NPMA. “Mosquitoes are mobile and can certainly fly into a yard and bite your client.”

He advises pest management professionals to discuss their ability to reduce mosquito populations and reduce the number of bites they receive on their properties.

On the job site, it’s the pest control professional’s job to inspect the property, says Dennis Jenkins, president of ABC Home & Commercial Services in Lewisville, Texas. The biggest thing to look for is standing water, in which Aedes larvae breed. Up to a ½ inch of water—which can be found inside tires, tree holes, pails, plastic jugs, clogged gutters, birdbaths, catch basins, children’s toys, abandoned pools and flowerpots— can be incubators for Aedes in someone’s yard.

When a potential breeding site is located, check the site to see if larvae are present. Aedes will often rest near the top of the water. If it’s tough to tell if larvae are present in stagnant water, extracting samples of the water with a dropper can help improve the view.

Next come the pesticides. Standing water that cannot be eliminated can be treated with an appropriately labeled larvacide, such as Methoprene or Bacillus thuringiensis, says Fredricks. Check with your state for licensing requirements to apply these products.

“Aedes mosquitoes live near their preferred food source—us,” Jenkins says. “They have adapted to live in our environment, so treatment must focus on the areas where they live and rest.” His company uses “an adulticide with a good residual.”

Fredricks agrees with that choice and suggests applications be done with a backpack blower, which produces large droplets of 150 millimeters to 200 millimeters. These droplets treat the interior of the plant architecture and deliver product to the locations where the mosquitoes are resting, according to Fredricks.

What can homeowners do to prevent it?

This question and the previous one go hand in hand because mosquito control is a team effort, Jenkins says.

“Customer cooperation is vital to the success of the program,” says Jenkins. “Without cooperation, unreasonable expectations will not only cause customer dissatisfaction, it will increase the liability for you and increase the likelihood that diseases will be vectored in the customer’s environment.”

Like the professional, the first thing the homeowner can do is eliminate breeding grounds around his or her property. It’s not “one and done,” as Jenkins says. Both parties must constantly monitor potential breeding grounds. Unseen breeding grounds are also less likely to form if the homeowner runs a fan outdoors to keep air moving.

The customer’s biggest responsibility is to try not to get bitten. Aedes mosquitoes typically only travel 100 meters or less, so control is hyperlocal.

Jenkins, who supplies clients with a document outlining control suggestions, says to consider wearing long-sleeve shirts, long pants and socks with shoes. Clothing also can be treated with preventive products, such as permethrin spray, which often lasts up to 10 washes. Even DEET mosquito repellents—which are also suggested by the EPA and CDC for reducing mosquito bites—go a long way in the fight to prevent Zika and other mosquito-borne illnesses.

Photos: Mosquito Joe, National Pest Management Association