We’re seeing movement on multiple infectious disease fronts in New York this week. The Legionnaires’ disease outbreak in Harlem has more than doubled. Rabies is elevated in some counties. And across the state, West Nile Virus is rising with mosquito activity. This week’s post will cover what these mean for your health, and how to reduce your risk. Let’s dive in.

Legionnaires’ outbreak grows

The cluster of Legionnaires’ disease in Harlem we reported on last week continues to grow. As of Wednesday, August 7, there are 67 cases, including 3 deaths. Affected zip codes are: 10027, 10030, 10035, 10037, and 10039. The risk to most is low, but if you live or work around these zip codes and have flu-like symptoms, it’s important to see a health care provider immediately for possible antibiotic treatment. If you do not have a health care provider, visit NYC Health + Hospitals.

Legionnaires’ disease symptoms include:

• Cough
• Fever
• Chills
• Muscle aches
• Shortness of breath

Most people exposed to Legionella bacteria won’t show symptoms, but the bacteria is particularly risky for people who are over 50, people who smoke or who have chronic lung disease, and those with weakened immune systems.

The most recent NYC Legionnaires’ report showed that among people infected in 2019-2022, more than 90% had at least one chronic medical condition and more than 50% were previous or current smokers. The most commonly cited medical conditions were diabetes and lung disease.

For outbreaks like this in NYC, the culprit is most likely a cooling tower. These usually sit on roofs and use water evaporation to cool the building. When bacteria-containing mist from a contaminated cooling tower drifts down, people can breathe it in and get infected. This means that residents in these zip codes can continue to drink tap water, bathe, shower, cook, and use their air conditioners.

Chelsea Cipriano shared this awesome image of why tap water is okay to drink and use. Cooling towers and drinking water tanks are different systems—it’s not the same water.

Graphic by Chelsea Cipriano.

We’ve had several Legionella outbreaks here linked to cooling towers previously. Every year, there are hundreds of cases detected in NYC.

Figure from NYC Department of Health and Mental Hygiene.

During the pandemic, cases actually declined compared to the previous couple of years. Masking and less movement around the city probably reduced exposure to mist from cooling towers, where Legionella can grow.

In 2015, one of the biggest outbreaks of Legionnaire’s disease in the U.S. was linked to a single cooling tower in the Bronx. That tower was responsible for 135 cases and 16 deaths.

In NYC, Legionnaires’ disease tends to be more common in Northern Manhattan and the Bronx. The reasons aren’t totally understood, but it’s likely due to a mix of factors, including lower maintenance of building systems like cooling towers (often tied to income and infrastructure disparities) and higher rates of chronic health conditions like diabetes, which can increase risk of severe infection.

Figure from NYC Department of Health and Mental Hygiene.

So, how can we prevent outbreaks?

In New York, the best way to prevent outbreaks is to test and treat cooling towers. Legionella bacteria is actually quite common in the environment, and a positive test doesn’t always mean there will be an outbreak. Still, New York has a system. Under state law, all cooling towers must be:

• Registered with the state
• Tested for bacteria
• Cleaned and disinfected after testing
• Maintained under a long term management plan

These requirements apply to all cleaning towers, including residential buildings, schools, office buildings, and businesses. When Legionella is detected, the tower must be cleaned and retested until it meets safety standards.

What does this mean for me?

While Legionella is common in the environment, most people exposed won’t get sick. But when conditions are right, and there are vulnerable groups living or working close to sources, exposure can lead to serious illness. If you live or work in one of the affected zip codes and have or develop flu symptoms, seek medical care as soon as possible. Early detection, proper maintenance, and rapid public health investigation are key.

Rabies in Nassau

Rabies is increasing in some New York communities. Nassau County just declared rabies an “imminent threat” in the county because of the increase in recent detections. Over the past year, 25 wild animals, including raccoons and feral cats, have tested positive for the virus in Nassau County—a sharp increase since it was declared eradicated in the county in 2016. In March, Suffolk County also noted an increase in rabies in raccoons.

In 2024, Westchester and Erie counties had the highest rabies detections of New York counties. Figure from New York Health Data.

Rabies, nearly 100% fatal for humans, circulates in the wild animals around us. 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 a monkey bit me while I was traveling—and I’m thankful I got the shots.

Question grab bag: A reader asks, “What’s the risk of rabies from a dog bite? Do we treat bites from wild and domestic animals differently?”

Great question. When we talk about rabies in the U.S., most of the risk surrounds wild animals, especially bats, raccoons, skunks, and foxes. Domestic dogs and cats can carry rabies, but it’s actually extremely rare in the U.S. In New York, because vaccination is mandatory, rabies in domestic cats and dogs is nearly unheard of.

With that said, when a person is bitten by an animal, there are multiple factors that go into determining the best course of action for rabies treatment, including:

• Vaccination status of the animal (if known)
• Type of animal (wild vs. domestic)
• Location of the bite: bites to the head or neck or deeper bites can increase risk because they are closer to the central nervous system
• If the animal can be quarantined and observed for illness
• Local rabies levels and alerts (some areas have more local circulation)

The bottom line is that whenever someone is bitten by an animal, they need to contact a medical provider and public health as soon as possible to discuss the best course of action.

WNV increasing in Long Island and rest of state

West Nile Virus continues to heat up this summer with more mosquito detections across the state and in New York City.

West Nile Virus detections. Figure from the New York State Department of Health. Annotations by YLE.

Now is the time to be wearing mosquito repellant at dawn and dusk, or consider wearing long sleeves if it’s not too hot. Annoyingly, I had a mosquito fly into my loose pants last week and bite me on the shins, so I’m switching to repellant. Also, dump standing water around your home—it’s the perfect breeding habitat for these pests.

Bottom line

You’re all caught up! See you next week. 🙂

Love,

Your New York 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.

It’s August, which means school is starting and fall is just around the corner. Normally, I’d be putting together a one-pager with everything you need to know about this year’s flu, Covid-19, and RSV vaccines: what’s available, who should get them, and when.

But this year is different: we don’t know these answers yet, which is highly unusual and could cause massive disruptions to your access in a few weeks.

Still, more than 60% of you said you wanted a deep dive into this topic. So here’s my best attempt to offer clarity amid the chaos: where things stand, what’s broken, and what you can do now, even as the system recalibrates or reinvents itself.

Buckle up.

What usually happens?

Think of our annual respiratory vaccine rollout as a giant domino setup. When the first domino falls—usually in February—the rest follow in a smooth, synchronized sequence, ending with shots in arms by early fall.

The fall respiratory vaccine process. Figure by Your Local Epidemiologist.

This system is designed for consistency and predictability, as there are many players who rely on the previous step to continue forward:

• February: Fall vaccine formulas are selected by FDA advisors.
• Spring: Expert advisory groups recommend which versions to use based on strain.
• Summer: Manufacturers scale up production; CDC defines eligibility.
• August: FDA finalizes labeling; insurers confirm coverage.
• Fall: Providers stock shelves. Patients show up. Shots go in arms (or butts, for babies).

This carefully timed cascade has been fine-tuned for more than half a century. Most years, it runs so smoothly that you never even hear about it.

What’s different in 2025?

Dominoes are missing, wobbling, and/or stalled. And now, the rest of the chain is backed up, driving confusion and potentially leading to changes in access. There are three main reasons for this:

1. Federal leadership is ideologically opposed to the system itself.

For the first time in modern history, the federal leadership overseeing vaccines doesn’t fully support their broad public health value.

HHS Secretary Robert F. Kennedy Jr.—a longtime vaccine critic—is now in charge of coordinating this entire system, and this has brought immense change:

• Experts are being sidelined. The CDC has just removed key professional organizations, such as the American Academy of Pediatrics, from advisory roles. In June, the 17 expert members of ACIP were dismissed and replaced.
• Federal agencies are no longer aligned. The CDC, FDA, and HHS are issuing conflicting signals on who will be eligible for COVID-19 vaccines, undermining confidence and paralyzing planning.
• Major decisions are being made in non-transparent ways. In May, RFK Jr. announced a new COVID-19 vaccine policy by video that reversed longstanding recommendations for healthy children and pregnant people without a clear scientific rationale.

2. Flu and RSV vaccines have yet to be signed off on.

Flu and RSV vaccines have been relatively smooth this year, as they were reviewed and recommended by ACIP (CDC’s external advisory committee) in June. But the final sign-off for these typically straightforward vaccines still hasn’t happened. RFK Jr. did revoke authorization for flu shots with thimerosal (based on disproven claims) but has yet to sign off on other flu formulations or the new RSV monoclonal antibody for infants. That delay is highly unusual and potentially troubling, as it could signal plans to restrict access. It could be due to the CDC leadership vacuum (CDC just got a CDC Director last week), but it’s unclear why RFK Jr. would sign off on one thing but not the others.

3. Covid-19 has the biggest policy vacuum.

This is where the dominoes have completely stopped:

• There is no national recommendation on who should get the updated Covid-19 vaccine this fall. This typically happens in June, but ACIP—the committee of external advisors that RFK Jr. replaced—chose not to vote on it. This is a big deal because the ACIP recommendation is linked not only to insurance coverage requirements but also to the number of doses health systems order in July (to be at clinics by the end of August). It is also linked to standing orders for pharmacists and other state-based authorities to administer the Covid-19 vaccine this fall.
• FDA is expected to narrow eligibility to “high-risk” groups only. That’s a shift from previous years, which encouraged widespread uptake to reduce community spread and increase ease of use.
• The revised label likely won’t be finalized until mid-to-late August, leaving insurers, providers, and the public in the dark.

This is a problem because insurers don’t know who to cover. Doctors are unsure who to prioritize. Pharmacies are uncertain about the number of doses to order and whether their staff can administer them. Vaccine campaigns are stalled.

What’s next?

A lot will unfold in the next few weeks:

• An outside group of experts (called the Vaccine Integrity Project) is meeting in August to review evidence of fall vaccines.
• In August, several professional medical societies will issue their own fall vaccine recommendations, regardless of what the federal government says. The American Academy of Pediatrics has already issued its flu recommendations, and the Society for Maternal Fetal Medicine has issued its fall vaccination recommendations for pregnancy.
• We will likely see an FDA label change for Covid-19 vaccines by end of August.
• Insurers will need to inform members about coverage for vaccines.
• Some states and insurers may fill the gaps to help maintain broader access.

The outcome of this effort will be consequential because it’s ultimately a test run for what’s to come next. RFK Jr. has signaled interest in reevaluating other routine vaccines like HPV, Hepatitis B, and measles.

The fall vaccine process changes in 2025 (indicated by red). Figure by Your Local Epidemiologist.

Naturally, this leads to more questions.

1. Will I be able to get a Covid-19 shot this fall, and if so, when?

Probably, but it may be hard. The FDA will likely change the Covid-19 vaccine label to restrict use to individuals 65+ years and who are at high risk. We don’t know what constitutes “high risk,” yet. If this happens, only people in that category would be officially eligible, and others would need to get the vaccine “off label.”

2. Can I get it off-label?

Technically, yes, but it’s complicated. Off-label prescribing is legal and common for many drugs, but vaccines are different because:

• Pharmacies often won’t—or can’t—administer vaccines off-label, based on corporate policies and state laws governing scope of practice. More than 90% of fall vaccines come from pharmacies.
• Insurers may not cover off-label use as this type of coverage currently varies widely by insurer, even when deemed medically appropriate by a physician.
• Although physicians should be able to prescribe and administer off-label, many won’t because of perceived liability challenges and confusion.
• Many electronic systems (like immunization registries) may block documentation or reimbursement.

So while a provider could prescribe it off-label, in practice, it’s likely that most people won’t be able to access it that way.

3. Will insurance cover it if I’m not “high-risk”?

Unclear, which is a significant concern. If the FDA updates the label to include only those with “high risk” conditions, insurers may only choose to cover the vaccine for those defined as high-risk. If you fall outside that group, you could face barriers to access—or end up paying out-of-pocket.

In June, AHIP and ACHP reaffirmed their commitment to access to affordable vaccines. Members of Congress have sent letters to major insurers urging continued access and coverage without cost-sharing, and 80 medical societies have called for the same. Still, much remains uncertain until we see confirmatory public statements and/or finalized policies from the payers.

4. Will pharmacies and doctors even have enough supply?

Manufacturers have been preparing for a fall rollout, and the vaccine supply itself is not expected to be a bottleneck. But pharmacies and providers are hesitant to place orders or schedule appointments without knowing who is eligible, what insurers will cover, or whether regulations will change at the last minute.

What should you do?

You can’t tip all the dominoes yourself, but you can help advocate to reset the missing and shaky pieces.

Most importantly, you can be a vaccine champion for yourself, your colleagues, your family, and your friends:

• Ask your health care providers and your pharmacy about their plans to stock and administer vaccines for all three viruses.
• Ask your insurance company about their coverage for these vaccines. If you’re insured through your employer, talk to them about what your plan will cover this season.
• When the time is right, get your fall vaccines and encourage people in your networks to do the same.
• Tell us what you need: what kind of information, talking points, or data points would help with these conversations?

If you’re a provider or public health professional:

• Start outreach to high-risk groups, like older adults for Covid-19 and infants for RSV.
• Secure inventory for fall vaccinations.
• Coordinate with local pharmacies if you don’t stock them yourself. Have a plan in place to direct people to where they can get a vaccine.
• Co-administer vaccines where possible to save time and increase uptake.
• Work with state medical societies and hospital associations to ensure there is clarity around professional liability, standing order impact, and “off-label” use.

Bottom line

What vaccines will be available this fall, who will be eligible, and where can you get them? We still don’t have clear answers. The usual chain of decisions—from recommendations to insurance coverage to provider readiness—has been disrupted.

But with clarity, coordination, and trusted messengers, the system can still protect millions if there’s a united front. It won’t be business as usual, but we can rebuild the line—one domino at a time.

Love, YLE