Can rats make you sick without biting you?

Yes. Most rat-borne illness in NYC spreads without a bite. Leptospirosis is contracted through contact with rat urine or urine-contaminated water, soil or food, and salmonella spreads when droppings or urine contaminate food and surfaces. According to the NYC Health Department, contact with rat urine is the main route for leptospirosis.

What is the most common disease from rats in NYC?

Leptospirosis is the rat-borne disease NYC public-health officials track most closely. The NYC Health Department reported a record 24 human cases in 2023, with locally acquired cases averaging about 15 per year from 2021 to 2023 versus roughly 3 per year from 2001 to 2020. Rats are the most common source, and the Bronx has seen the most cases.

Are mice dangerous, or just rats?

Mice carry real health risks too. House mice shed allergens in their urine, droppings and dander that are a major indoor asthma trigger for NYC children — in one inner-city study, about 42% of asthmatic NYC kids were sensitized to mouse allergen. Deer mice (more rural than urban) can also carry hantavirus, a rare but potentially fatal lung disease per the CDC.

Can you get sick from cleaning up rat or mouse droppings?

Yes — and cleanup is exactly when risk spikes. The CDC warns that sweeping or vacuuming dry rodent droppings can aerosolize particles you then breathe in, which is the main hantavirus exposure route. Ventilate the area, wet droppings with disinfectant before wiping, wear gloves and a mask, and never dry-sweep a heavy infestation.

What are the symptoms of leptospirosis?

Per the NYC Health Department, leptospirosis symptoms include fever, headache, chills, muscle aches, vomiting, diarrhea, jaundice and red eyes. Untreated, it can progress to kidney failure, liver damage, meningitis and respiratory distress. It is treatable with antibiotics such as doxycycline or penicillin, so see a doctor early if you've had rat exposure.

What is rat-bite fever?

Rat-bite fever is a bacterial infection (Streptobacillus moniliformis in North America, per the CDC) spread through bites, scratches, handling rats, or ingesting food or water contaminated with rat droppings. Symptoms — fever, chills, muscle aches and often joint pain or rash — usually appear 3 to 10 days after exposure. It is treatable with antibiotics but can be serious if ignored.

Why does NYC treat rats as a health issue and not just a nuisance?

Because rodents directly threaten health and food safety. The NYC Health Department inspects for rats, cites rodent evidence in housing and restaurants, and runs Rat Mitigation Zones in high-complaint neighborhoods. The 2023 spike in leptospirosis cases is a direct example of rat density translating into human illness.

How do I lower the health risk from rodents in my apartment?

Eliminate the rodents and seal them out. Remove food and water sources, store food in hard containers, clean droppings safely (wet, don't sweep), and seal entry points so new rodents can't enter. Because NYC infestations are usually building-wide, professional rodent control that combines knockdown with exclusion is the most reliable way to reduce exposure.

Rat-Borne Diseases & Health Risks in NYC: What Rats and Mice Can Actually Make You Sick With

Health information, not medical advice. This explains the documented health risks rats and mice pose in New York City, drawing on the CDC and the NYC Health Department. If you think you’ve been exposed or are unwell, see a doctor.

The short answer

Rats and mice in NYC are a public-health problem, not just an unpleasant one. They can transmit leptospirosis — the rodent disease NYC tracks most closely — through their urine; rat-bite fever and salmonella through bites, droppings and contaminated food; and, in the case of house mice, they shed the allergens that are one of the biggest indoor asthma triggers for city kids. Deer mice can also carry hantavirus. That’s why the NYC Health Department treats rodent evidence as a hazard in homes and restaurants — and why a rat problem is something to deal with promptly, not live with. If you’re past the “is this dangerous?” stage and ready to act, see how to get rid of rats in NYC and our rat & mouse control service.

Leptospirosis: NYC’s signature rat disease

Leptospirosis is the rat-borne illness New York City watches most. It’s a bacterial infection spread through the urine of infected animals, and in NYC the rat is the most common source (NYC Health Department). People get it through contact with rat urine — or with water, soil or food contaminated by it — usually through broken skin, the eyes, nose or mouth.

The numbers tell the story. The NYC Health Department reported a record 24 human cases in 2023, and locally acquired cases averaged about 15 per year from 2021–2023, versus roughly 3 per year from 2001–2020 — a roughly five-fold jump. Most reported cases have been adult males, most frequently in the Bronx (NYC DOH Health Alert, 2024). Symptoms include fever, headache, chills, muscle aches, vomiting, diarrhea, jaundice and red eyes; untreated, leptospirosis can cause kidney failure, liver damage, meningitis and respiratory distress. It is treatable with antibiotics such as doxycycline or penicillin when caught early.

This is the disease that makes NYC’s basements, alleys, trash corrals and damp cellar floors a real concern — anywhere rats are active and their urine pools or seeps. Building superintendents, sanitation and construction workers, and anyone clearing a rat-infested basement face the most exposure.

Rat-bite fever and salmonella

Rat-bite fever (RBF) is caused, in North America, by the bacterium Streptobacillus moniliformis (CDC). Despite the name, you don’t need to be bitten — it spreads through bites, scratches, handling rodents, or ingesting food or water contaminated with rat droppings (when foodborne, it’s known as Haverhill fever). Symptoms — fever, chills, muscle aches, and often a rash or joint pain — typically appear 3 to 10 days after exposure, and roughly half of patients develop polyarthritis (CDC). RBF is rare but treatable with antibiotics; left untreated it can become serious.

Salmonellosis is the everyday food-safety risk. Rats and mice carry Salmonella and shed it in their droppings and urine, contaminating food, prep surfaces and storage as they travel. This is precisely why rodent evidence is a serious violation in NYC restaurants and bodegas: a few droppings in a dry-goods shelf or behind a prep line means potential contamination of everything around it. For the kitchen side of this, see our restaurant pest control approach.

Mice, allergens and childhood asthma

Mice are easy to dismiss as harmless, but in New York City they’re a documented asthma driver. House mice constantly shed proteins in their urine, droppings and dander that become airborne indoor allergens — and NYC’s dense, attached housing concentrates that exposure.

Research on inner-city children is striking. In studies of NYC kids with asthma, mouse allergen was found at high levels in their homes, and New York had among the highest pest-allergen sensitization rates measured — about 42% of asthmatic NYC children sensitized to mouse allergen and 56% to cockroach (National Cooperative Inner-City Asthma Study; Columbia University research). For a child with asthma, a mouse infestation isn’t a nuisance — it’s a trigger living in the walls. Clearing the mice and cleaning up the contamination is part of managing the asthma. If mice are your issue specifically, start with how to get rid of mice in a NYC apartment.

Hantavirus: rare in the city, but worth knowing

Hantavirus pulmonary syndrome (HPS) is the most severe rodent disease — and the one most tied to cleanup. In the U.S. it’s spread mainly by the deer mouse carrying Sin Nombre virus (CDC). People get it by breathing in particles when disturbing droppings, urine or nesting material — which is why dry-sweeping or vacuuming a rodent-infested space is the dangerous move. Symptoms (fever, muscle aches, then cough and shortness of breath) appear 1 to 6 weeks after exposure, and HPS can be fatal.

The reassuring part: hantavirus is far more a rural and suburban risk than an inner-city one, because the deer mouse — not the house mouse — is the reservoir. But the cleanup lesson applies to every NYC mouse and rat job: ventilate first, wet droppings and nests with disinfectant before wiping, wear gloves and a mask, and never dry-sweep. This is one reason professional rodent work includes safe sanitation guidance, not just trapping.

Bites, contamination and the everyday risks

Beyond named diseases, rodents create routine hazards in a NYC home or business:

Bites and scratches, especially toward small children or sleeping infants in heavily infested units, which can transmit infection.
Food and surface contamination from droppings and urine across pantries, counters and restaurant storage.
Parasites — rats and mice carry fleas and mites that can move onto pets and people.
Fire and structural risk from gnawed wiring, which is a safety issue layered on top of the health one.

Why prompt rodent control is a health decision

Here’s the NYC-specific point: rodent pressure in this city is relentless and shared. Attached brownstones, connected basements, trash corrals, subway-adjacent blocks and aging plumbing chases mean a rat or mouse problem is rarely contained to one unit — and the health exposure compounds the longer it runs. The NYC Health Department’s own posture reflects this: it inspects for rats, cites rodent evidence as a violation, and operates Rat Mitigation Zones in the highest-complaint neighborhoods, while the city’s containerization rules (sealed trash bins) are explicitly aimed at cutting the food supply that drives rat density. Citywide 311 rat-sighting reports have actually declined recently (about 20,000 reported in the year to late 2025, down from roughly 25,000 the prior year, per DSNY) — progress, but rats are still everywhere there’s food and shelter.

For your home or business, the takeaway is simple: the disease risk drops when the rodents are gone and stay gone. That means combining knockdown (trapping and tamper-resistant baiting) with exclusion — sealing the entry points so the next wave can’t move in — plus safe cleanup of contaminated areas. Knockdown alone doesn’t lower exposure for long in NYC, because the building or block re-seeds within weeks.

If you’ve got active rodents, droppings in multiple areas, or an at-risk household member (a child with asthma, an infant, anyone immunocompromised), don’t wait it out. Our rat & mouse control finds and seals the entry points DIY misses, knocks down the population safely around children and pets, and advises on the sanitation that actually removes the health risk. For cost expectations, see our rat exterminator cost guide for NYC.

Sources

NYC Health Department — Leptospirosis health topic and 2024 Health Alert (record 2023 cases; transmission via rat urine; symptoms and treatment).
U.S. Centers for Disease Control and Prevention (CDC) — Rat-Bite Fever clinical overview; Hantavirus (HPS) clinical and prevention guidance; rodent-control and cleanup guidance.
National Cooperative Inner-City Asthma Study; Columbia University research on cockroach and mouse allergen and NYC childhood asthma.
NYC Department of Sanitation (DSNY) / NYC 311 — rat-sighting complaint data and Rat Mitigation Zones.