An emerging infection carried by the same ticks that transmit Lyme disease has sickened a record number of Mainers this year, according to the Maine Center for Disease Control and Prevention. While rarely fatal, the disease can cause serious illness if left untreated.
So far in 2014, Maine has confirmed 103 cases of the bacterial infection anaplasmosis, already exceeding the 94 cases recorded in all of 2013. While lesser-known than the far more prevalent Lyme disease, anaplasmosis can lead to similar long-term effects without a proper diagnosis, including neurological and joint problems and kidney failure.
Rarely, it causes brain swelling and meningitis. Anaplasmosis results in death in fewer than 1 percent of cases, according to the U.S. CDC.
Both anaplasmosis and Lyme are transmitted by the eight-legged deer tick, which also carries the less-common infections babesiosis and Powassan virus. This year Maine has recorded 20 cases of babesiosis, a parasitic infection that can especially sicken those with weak immune systems and people who have had their spleen removed, according to Maine CDC. The state had 36 cases in 2013.
No confirmed cases of Powassan have yet surfaced in 2014, but the infection claimed the life of a Rockland-area artist last December. Powassan is also carried by the woodchuck tick.
Maine experienced a record year for Lyme in 2013, with 1,376 cases. This year, the Lyme count has reached 552, though Maine CDC Director Dr. Sheila Pinette expects that figure to rise dramatically, as Lyme disease cases often take months to diagnose and classify.
A single deer tick can harbor and transmit several of the infections at once.
Maine CDC issued a health alert on Aug. 7 to remind providers about the risks and prevalence of the diseases.
While doctors treat anaplasmosis with the same antibiotic prescribed for Lyme disease, the infection doesn’t result in Lyme’s hallmark bull’s-eye rash. It’s caused by a different organism called Anaplasma phagocytophilum that causes severe flulike symptoms, such as body aches, fever, chills and headache.
Anaplasma lives in white blood cells, causing all-over discomfort as the cells circulate through the body. Symptoms typically appear within one to two weeks of a tick bite.
“Anaplasmosis can be missed unless you think about it because its symptoms are not specific,” said Dr. Robert Smith, an infectious-disease physician at Intermed in Portland.
Maine’s case count is based on positive lab tests, which must be reported to public health officials. But the federal CDC didn’t require such reporting until 1999. Since then, awareness and education about anaplasmosis among health providers and the public has grown, said Pinette.
“I think it’s probably been there all along, it’s just that it wasn’t being tested for, and now providers know to test,” she said.
A DNA test during the first week or two of infection, which detects the anaplasma organism, provides the most accurate diagnosis, Smith said. Another test for antibodies the body produces in response to the infection may lead to positive results for months or even years after a tick bite, he said.
Most hospital labs don’t offer the DNA test in house, but can send out blood for testing offsite, Smith said.
Much like Lyme, the sooner those infected with anaplasmosis get treatment, the better.
Low blood platelets, anemia, electrolyte dysfunction and elevated liver function are all early signs of anaplasmosis doctors should take seriously, Pinette said.
Dick Atlee, 69, of Southwest Harbor contracted the disease in the spring of 2009, spending a week at Eastern Maine Medical Center in Bangor with a worrisome fever. His plummeting platelet count led doctors to first suspect he had leukemia.
But infectious disease physician Dr. Imad Durra tested Atlee for anaplasma on a hunch, even though it remained early in the season for tick-borne diseases and anaplasma was nearly unheard of in Maine at the time, Atlee said.
When the test results came back, his perplexed oncologist was deeply relieved, he said. A round of antibiotics rid him of the infection.
Atlee had never heard of anaplasmosis.
He also never recalled getting a tick bite. He takes precautions, including wearing long sleeves and tucking his pants into his socks when he spends time outside.
“It just always stuns me, walking around here, the utter disregard for ticks,” Atlee said. “People just walking around with shorts and halter tops. You wonder what are they thinking.”
While health providers have grown more aware of anaplasmosis, Smith suspects Mainers are also increasingly exposed to the infection. The deer tick has spread across Maine over the past two decades, and tick populations have become more dense in some areas, said Smith, also principal investigator at Maine Medical Center’s Vector-Borne Disease Laboratory.
Rates of anaplasmosis are higher along the coast, especially in heavily wooded areas where deer ticks congregate.
“It tends to follow the same pattern that you see with Lyme disease,” Pinette said.
Nationally, 90 percent of all reported anaplasmosis cases have occurred in six states: New Jersey, Connecticut, New York, Rhode Island, Minnesota and Wisconsin.
If you’ve removed a feeding tick from your body a week or two before developing a summer flulike illness, see your physician, Smith recommended.
The elderly and people with immune deficiencies are more susceptible to developing serious symptoms.
The risk of encountering an infected tick is highest from May through July, but remains in August, he said.
Smith said the emergence of tick-borne diseases doesn’t prevent him from enjoying the outdoors. But he urged Mainers to take steps to prevent a tick bite.
“It doesn’t change my interest in outdoor activities and being active,” he said. “Fortunately these diseases, if recognized, generally respond very well to antibiotics.”
Public health experts’ awareness of the number of infections deer ticks can carry in their tiny bodies continues to grow with each passing year. Along with Lyme, anaplasmosis, babesiosis, and Powassan, the MMC Research Institute is also studying two other agents, Smith said.
Deer tick virus can cause severe illness but has affected only a small number of individuals nationally, including one in Maine last year, he said. Another bacterial infection researchers know less about can also result, in rare instances, from deer tick bites, Smith said.
“We actually have five different microbial agents to be aware of from exposure to deer ticks,” he said.