Anaplasmosis Infections Climbing in New York at Alarming Rate

Ticks have always been an unpleasant part of summer in New York, but recent years have brought a notable surge in tick-borne illnesses throughout the state.

The New York State Department of Health reports that over the past three years, the state has averaged roughly 17,500 Lyme disease cases annually.

But Lyme is not the only threat. Anaplasmosis, another serious illness spread by ticks, is also becoming more common.

Anaplasmosis is caused by the bacterium Anaplasma phagocytophilum, transmitted through the bite of an infected tick. Unlike Lyme disease, it typically does not cause a rash, which can make it harder for patients and doctors to recognize early on. It is not spread from person to person.

Symptoms usually develop within one to two weeks of a tick bite and may include:

-Fever and chills

-Headaches and muscle aches

-Nausea, vomiting, and diarrhea

-Loss of appetite

Without timely treatment, the infection can lead to severe outcomes such as respiratory failure, bleeding issues, organ failure, or even death.

The Centers for Disease Control and Prevention advises treating suspected cases promptly with the antibiotic doxycycline.

Findings from the Upstate Tick Testing Lab reveal a striking increase in ticks carrying Anaplasma, jumping from just 2% in 2019 to 18% in 2025, a 9x rise.

Since 2015, New York has averaged about 1,300 anaplasmosis cases each year. Doctors have been noticing the trend firsthand. Dr. Kris Paolino, an infectious disease specialist at Upstate University Hospital, said he saw 19 cases in 2024 alone, compared to only two between 2016 and 2020.

“I’ve seen patients end up in the ICU,” Dr. Paolino told WSYR-TV. “Every year, you hear about one or two cases that end in an unfortunate death.”

The chance of encountering an infected tick depends both on the region and the stage of the tick’s life:

-Nymph ticks are tiny, easy to miss, and more likely to spread Lyme disease and anaplasmosis.

-Adult ticks are larger and easier to detect but can still transmit illnesses.

State health officials say nymph tick risk is highest in the Hudson Valley, while adult tick risk peaks in the Finger Lakes region.

To reduce the risk of tick bites, the Department of Health recommends:

-Wear long sleeves, long pants, and closed-toe shoes outdoors.

-Keep long hair tied back.

-Check yourself for ticks frequently when outside.

-Shower promptly after returning indoors.

-Place clothes in a dryer on high heat for 10 minutes to kill ticks.

-Inspect pets for ticks.

-Use EPA-registered insect repellents, and apply them after sunscreen.

Anaplasmosis Infections Climbing in New York at Alarming Rate