Ticks & Disease

When it comes to the worst disease transmitters, ticks rank right up there with mosquitoes.

According to the Centers for Disease Control and Prevention (CDC), disease cases from mosquito, tick and flea bites tripled in the U.S. from 2004 to 2016. In addition, nine new germs spread by mosquitoes and ticks have been discovered or introduced since 2004.

One of the most devastating and widespread illnesses is Lyme disease, which is transmitted by blacklegged ticks that carry the bacteria Borrelia burgdorferi and B. mayonii.

The number of reported cases of Lyme disease in the U.S. has tripled since the late 1990s, said the CDC. In 2018, a total of 33,666 confirmed and probable cases were reported to the agency. While this is 21 percent fewer cases than reported in 2017, the geographic distribution of areas with high incidences of Lyme disease appears to be expanding. Based on data reported to the National Notifiable Disease Surveillance System, the number of counties with an incidence of 10 or more confirmed cases per 100,000 persons increased from 324 in 2008 to 415 in 2018.

In addition to Lyme disease, cases of tick-transmitted anaplasmosis/ehrlichiosis, spotted fever rickettsiosis (including Rocky Mountain spotted fever), babesiosis, tularemia and Powassan virus disease all increased in previous years. In 2016 there were a total of 48,610 reported cases and in 2017 there were 59,349 reported cases. According to the CDC, reported cases capture only a fraction of the overall number of people with tickborne illnesses.

PUBLIC AWARENESS. According to the PCT 2020 State of the Tick Control Market survey, sponsored by Zoëcon Professional Products, 41 percent of PMPs said customers were concerned about the public health risks associated with ticks. The survey was conducted in March by Readex Research, a privately held research firm in Stillwater, Minn.

“They know how it’s transferred and how scary it can be,” said Mark Constantino, owner of Arkadia — Eco Pest Control, Randolph, N.J., of how customers view tick-borne illness. Awareness is likely higher among people living the Northeast, Mid-Atlantic and Great Lakes regions, where the incidence of Lyme disease is highest. In 2018, 11 states in these areas reported more than 1,000 confirmed and probable cases of the disease, reported the CDC.

In other locations, customer reactions can be mixed. “We have some people who don’t care at all and we have some people who know every disease that a tick can carry and are concerned about it,” said Cassi Magnus, co-owner of Phoenix Pest and Wildlife Control in Danville, Ind. “There’s really no in between. It seems like people really care or they really don’t,” she said.

Some customers are concerned about their pets. “More than humans are susceptible; so are our dogs and our cats,” explained Sherry Tallent, co-owner of A&A Pest Control in Cuba, Mo. She lost her cat to Cytauxzoonosis, a tick-transmitted protozoan parasite, also called Bobcat fever (after the parasite’s natural host).

Todd Leyse, president of Adam’s Pest Control in Medina, Minn., is surprised more people don’t call for tick control. “I’m surprised we don’t get more calls. There are more ticks and Lyme disease out there than many years ago when it was a media darling,” he said.

The PCT survey found 36 percent of PMPs believe the pest management industry has done an effective job of communicating the public health risks associated with ticks, while an almost equal number — 34 percent — are unsure about this.

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AN EXPANDING RANGE. According to the PCT survey, 49 percent of PMPs said the incidence of tick infestations increased in their markets over the past year (see chart).

That may be because the geographic range of some species is increasing. The lone star tick, which transmits pathogens that cause ehrlichiosis, tularemia and Heartland virus disease, has expanded from its original territory in the Southeast to northern and midwestern states, reported the CDC. And the number of counties with the blacklegged tick, which causes the most cases of Lyme disease, babesiosis and anaplasmosis in the U.S., has more than doubled over the past 20 years.

Mohammed El Damir, technical and training director at Adam’s Pest Control, is especially concerned about cases of tick-borne disease such as Rocky Mountain spotted fever that have been newly documented in the Midwest.

Ticks may cause more disorders than we realize. Scientists currently are studying how ticks may cause an allergy to mammalian meat, called alpha-gal allergy.

And a new invasive species, the Asian longhorned tick, also is being studied. While bites from this tick in other countries can make people and animals seriously ill, so far, no harmful germs have been found in specimens collected in the U.S., reported the CDC. This tick was reported for the first time in the U.S. in 2017 and now can be found in 12 states.

PMPs anticipate robust tick populations this year, mainly due to the mild winter. As such, they’re educating customers about how to reduce their exposure and modify backyard habitats conducive to ticks and the rodents and wildlife serving as hosts.

Tick management is an opportunity for the industry. According to the CDC, about 80 percent of municipal vector control organizations lack critical prevention and control capacities to control ticks and other vectors. This makes PMPs the front-line defense in combatting the pests, said Constantino. “The town’s not going to come and treat your property for ticks.”