Editor’s note: This is the first in a three-part series about tick identification, disease and encounter prevention.  

Deer ticks can be carriers of the bacteria that causes Lyme disease. Griffin Dill photo

REGION — Ticks: tiny arachnids that depend on the blood of hosts to survive. Their M.O. is to attach to their host and then gorge on its blood. As they do this, they can pass along a variety of diseases. Some of which are deadly, all are unpleasant.

Between 2013 and 2018, confirmed and probable cases of Lyme reported to Maine Center for Disease Control and Prevention increased from 1384 to 1404, or 1.42%. The number of confirmed cases peaked in 2017 at 1,855.

Babesiosis increased from 36 in 2013  to 101 in 2018, or 64%. The most alarming increase is with reports of Anaplasmosis, which rose from 94 cases in 2013 to 476 cases in 2018, an increase of 406%.

According to Maine CDC Tracking Network, there have been 284 cases of Lyme Disease, 402 cases of Anaplasmosis, and 54 cases of Babesiosis reported statewide between Jan. 1 and Aug. 1.

On Wednesday, July 24, Maine CDC announced in a press release a case of Powassan virus infection, a potentially deadly tick-borne illness, had been confirmed in a Maine resident. It is the first confirmed case in the state since 2017. According to the release, Maine has identified 11 Powassan virus cases since 2000.

Each of these diseases comes with its own roster of symptoms ranging from fever and chills to death, according to Maine CDC.

While ticks are to blame, how can one be sure what species, and ultimately what potential diseases, they might have been in contact with?

According to UMaine Extension, 15 different species of ticks have been identified in Maine, although not all are permanent residents. Some species, like the Gulf Coast tick, may arrive on wildlife hosts such as migratory birds and do not establish viable populations, said Entomologist Griffin Dill, who operates the UMaine Extension “Tick Lab” at the University of Maine in Orono.

An adult male dog tick found during a tick surveillance sweep. Dee Menear/Advertiser Democrat

The most commonly encountered species in Maine – and the most problematic –are the deer or black-legged tick, American dog tick and woodchuck tick.

According to the UMaine Extension website, deer ticks are responsible for several serious tick-borne diseases including Lyme disease, Anaplasmosis, Babesiosis, and Powassan virus. Woodchuck ticks are generally considered a nuisance and do not transmit Lyme disease. They can, however, transmit Powassan virus.

Information obtained from Maine Center for Disease Control and Prevention Tracking Network. The data does not include the number of out-of-state residents who acquired the diseases in Maine. Maine CDC counts cases by where the patient lives, not the location of exposure.

American dog ticks, also known as wood ticks, can transmit Rocky Mountain spotted fever. There have been no confirmed Maine-acquired cases of Rocky Mountain spotted fever, as of yet. Although American dog ticks can contain the bacteria that causes Lyme disease, they seem to be unable to transmit the bacteria to humans or other hosts.

If a tick is found and its species can not be determined, it can be sent to the tick lab for free identification.

“So far this year, we have received about 1,600 tick samples,” Dill said on Wednesday, July 24. “Of those, roughly 62% were identified as deer ticks, 34% as wood ticks and 2% as woodchuck ticks.”

The remaining 2% are less prominent species or, in some cases, not even a tick.

The lab can also perform DNA tests on deer ticks for the presence of the pathogens that cause Lyme disease, Anaplasmosis and Babesiosis, he added. About 900 deer tick DNA samples have been tested so far this year.

“Roughly 40% tested positive for the pathogen that causes Lyme disease,” he said. “Anaplasmosis pathogens were found in about 8% of the samples and Babesiosis in about 6%. Some samples are co-infected with two or more pathogens.”

The DNA testing costs $15. It typically takes three business days for results to be available.

The lab does not currently test for Powassan virus, he said.

As a disclaimer, Dill said if you’ve been bitten by a tick, do not wait until testing results are available to consult a doctor if there are concerns. Just because a tick is infected, it does not necessarily mean its host is, he added.

A University of Maine Cooperative Extension tick testing report reveals the results of a deer tick submitted for testing. Submitted photo

“The testing of tick samples is intended to provide information on ticks in Maine,” he said. “It is not intended to be interpreted as a medical diagnosis.”

To submit a tick for identification or testing, visit the tick lab website at extension.umaine.edu/ticks.

UMass Amherst tick testing program, found at tickreport.com, offers more comprehensive DNA testing. Of the 571 Maine ticks tested by the program in the last year, 211 tested positive for the pathogen that cause Lyme disease. The pathogen that cause Anaplasmosis was present in 52 samples. Babesiosis pathogens were found in 51 ticks. None of the ticks tested carried the Powassan virus.

In addition to tick identification and testing, UMaine Extension website resources include information on the biology and management of 14 tick species in Maine, tick submission instructions, tick removal guidelines, a tick photo gallery, and links to information on tick-borne diseases transmitted in Maine.


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