I’m back on the New York health beat after taking a vacation to visit family in Hawaii! I’m a little more tan, definitely more relaxed, and still finding sand in and around my apartment.
Thanks for your patience with last week’s break—rest is public health too. 🙂
And we are now in the full swing of summer, and the health issues that come with it. This week we’ve got updates on ticks, mosquitoes, rabies, and what to know about the toxic yew plant in Central Park.
Understanding the risks and how to manage them will help with enjoying all that summer has to offer.
We are in peak tick season in the Northeast right now. The Northeast has seen high tick activity for the last three weeks, not a single peak like last year.
What’s especially important for New Yorkers to know is that ticks are now not just something to think about after a weekend upstate, hiking, or camping. We are seeing increasing reports of ticks in city parks and urban areas in the Northeast—the New York Times covered it last week.
It’s important to start spreading the word about this because those of us who live in the city, myself included, may not be used to seeing ticks around city parks or doing tick checks after going on picnics or walking our dogs. But now may be the time to start, especially if you have dogs or outdoor cats.
Ticks in the city can still carry disease. Lyme disease is the most common tick-borne disease among New Yorkers (more than 9,000 cases annually), followed by babesiosis and anaplasmosis.
Tick surveillance and testing by the NYC Health Department.
For the rest of New York state outside of NYC and Long Island, tick risk is a combination of low and moderate, but the message is that tick risk is present everywhere across the state.
No matter where you are in New York, protecting yourself and family means avoiding ticks:
- Use repellent that contains 20% or more DEET, picaridin, or IR3535 on exposed skin.
- Treat clothing and gear with products containing 0.5% permethrin.
- Walk in the center of trails and avoid brushing against tall plants.
- Do tick checks after spending time outdoors, including time in city parks. For kids, especially check under arms, in and around ears, in the belly button, and in their hair.
- Toss your clothes in a hot dryer for 10 minutes to kill any hidden hitchhikers (though I know this is difficult or impossible if you don’t have a washer/dryer in your building).
- Treat dogs for ticks. Dogs are very susceptible to tick bites and may also bring ticks into your home.
- If you find a tick attached to your skin, remove it promptly with tweezers and monitor for symptoms. Early treatment is key to preventing severe illness.
The mosquito season is just starting in New York. With more mosquitos, expect more news of mosquito-borne illnesses, like West Nile Virus (WNV). Last year, WNV was detected in mosquitoes as early as July 1. We can expect these pests to hang around until about November when temperatures start to drop.
Most mosquitoes do not carry pathogens that can hurt us. Among those that do, the most common is WNV, and even that is relatively rare. In 2025, 59 human WNV cases were reported across New York state, including in New York City. While most people who get WNV won’t show symptoms, the virus can be dangerous for those who are over 60 years old or have immunocompromising conditions.
Last year, 16 counties in New York detected WNV, and in NYC, it was detected in every borough.
West Nile Virus found in mosquitoes across New York state counties. Figure from New York state.
NYC and New York haven’t started publishing their weekly mosquito reports yet, which will have up-to-date detection maps. This should start soon.
But now is the time to start preventing bites from these annoying bugs:
- Wear EPA-approved mosquito repellent outside, especially during peak mosquito activity time: dawn and dusk. If you are using sunscreen, apply sunscreen first and insect repellent second.
- Avoid being outside when mosquitoes are most active (the morning and evening)—but this can be really hard.
- If it’s not too hot, long sleeves and long pants can protect against bites.
- Dump standing water (think flower/plant saucers, buckets, fountains, toys that have been sitting outside, etc.) to eliminate mosquito habitats.
New Yorkers should be aware of rabies this summer as we spend more time outside, and potentially in contact with wildlife.
Rabies, nearly 100% fatal for humans, circulates in the wild animals around us. In New York, rabies is most commonly seen in raccoons, skunks, bats, foxes, and free roaming cats. However, any mammal can be infected, including household pets, like dogs and cats, and other domestic animals such as horses and livestock.
Rabies is detected across New York state, with some pockets of really high activity.
Last year, I covered large increases in rabies in raccoons seen in Nassau County. And while increases in rabies may sound scary, there are practical steps we can implement that make risk to humans pretty low.
What you can do:
- Ensure that your pets are up to date on rabies vaccines—in New York, state law requires it. All New York counties offer free rabies vaccination clinics. For more information, contact your local health department.
- Do not touch or get close to wild animals, including feral cats. If you are bitten, immediately wash the wound with soap and water and contact your medical provider. Advise children to immediately tell an adult if they are bitten or scratched by an animal.
- If you see a wild animal that doesn’t look well or you encounter a dead animal, contact your local health department or 311 if you are in New York City. Rabies symptoms in animals include tiredness, confusion, difficulty moving, aggression, drooling, and chewing objects like wood, soil, or stones.
Getting vaccinated is crucial if a wild animal bites you. I learned that firsthand in college when I was traveling and was bit by a wild monkey. I’m so thankful I got the shots.
Earlier this month, a carriage horse named Deniz died in Central Park after eating a lethal amount of Japanese yew, according to necropsy details from Cornell Veterinary Hospital. There’s now a debate over who’s responsible, but the public health takeaway is simpler: plants in parks, yards, planters, and landscaping can be dangerous, and it’s important to pay attention to what pets and kids might get into.
Japanese yew is a common ornamental shrub in the United States, where it is used in landscaping and Christmas wreaths. However, it contains taxine alkaloids, which can disrupt the heart’s electrical system and cause rapid collapse or sudden death in people and animals. ASPCA and Cornell list yew as toxic to dogs, cats, horses, and livestock. Shakespeare actually used yew as the poison in Macbeth.
Despite it being poisonous, Japanese yew is planted in Central Park, and it sounds like the horse took a big bite of the plant without the carriage driver noticing (thought the park notes that horses are forbidden from eating park plants).
This doesn’t mean we need to panic every time we pass a shrub, but it does mean we should be aware. Here are some tips:
- Don’t let pets, horses, or kids chew on unknown plants or berries.
- If you trim yew or other toxic shrubs, clean up clippings carefully and don’t toss them where animals can reach them. I also read some accounts of people feeling sick after using yew wood in outdoor fires.
- If a pet may have eaten something toxic, call your veterinarian or ASPCA Animal Poison Control.
- For human exposure, call Poison Help at 1-800-222-1222.
Summer brings specific health issues, including infectious diseases transmitted by ticks, mosquitoes, and animals. But a little prevention and awareness go a long way in keeping us and our pets healthy to fully enjoy summer. 🙂
Love,
Your NY Epi
Dr. Marisa Donnelly, PhD, is an epidemiologist, science communicator, and public health expert. This newsletter exists to translate complex public health data into actionable insights, empowering New Yorkers to make informed and evidence-based health decisions.
