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

Well, July just flew by. August is here—bringing peak mosquito season, back-to-school bustle with lower vaccination rates, and,

unfortunately, Covid-19 and hand, foot, and mouth. Here’s what may impact your health, some communication tips

in our recent NEJM article, and, as always, some good news to start your week!

Let’s dive in.

Disease “weather” report

Covid-19

The summer Covid-19 wave is growing—especially in the South and West—but national levels remain relatively low compared to this time

last year. Infants under 6 months old are the most impacted right now, accounting for the highest rate of emergency room visits

for Covid-19.

How high will this wave get? No one knows for sure, but I wouldn’t be surprised if it passes last winter’s peak.

That season was mild, and many people haven’t been infected in a while, leaving them more susceptible to infections.

Sources: CDC Covid Data Tracker (top), PopHIVE Respiratory Diseases (bottom), annotated by YLE

If you squint, overall hospitalizations are starting to increase, which makes sense given they still lag the early indicators like wastewater.

But each year we are getting fewer severe diseases in a step-like fashion. I expect this year to be no different.

Covid-19 hospitalizations, United States. Source: CDC; Annotated by Your Local Epidemiologist

Hand, foot, and mouth disease

Pediatricians and parents are anecdotally reporting more cases of hand, foot, and mouth disease than usual for this time of year.

It’s hard to confirm in the data, as this disease isn’t a “nationally reportable disease” (i.e., clinician and public health department

reporting not required). But among the few states that do track, like Maryland, New Jersey, and Virginia, reports are above normal.

People are also searching for it on Google more than usual.

Google Trends data for “Hand, Foot, and Mouth” disease by Your Local Epidemiologist on August 3, 2025.

• Who it affects: Most common in children under 5, but anyone can get it.
• Symptoms: Low-grade fever and red rashes on the hands, feet, and mouth, which can turn into painful sores.
• How it spreads: It’s very contagious for 7-10 days through saliva, mucus, sneezing, and stool.
• What to do:
  • Wash hands frequently
  • Disinfect shared surfaces
  • Keep sick kids home
  • Watch for dehydration, especially if sores make drinking water painful

Peak mosquito season is here

August marks the height of mosquito season—and with it, an uptick in local news about city/county spraying and human cases of

West Nile virus.

West Nile Human Cases last year (2024), Source: CDC West Nile Virus Historic Data

This is prime time for mosquito-borne diseases because mosquitos are cold-blooded and transmission is a bit like a chemistry experiment.

If it’s too cold (below ~16°C, or ~60°F), the mosquito life cycle slows down too much to spread disease.

Closer to the “magic temperature” of ~25°C (77°F), mosquitoes are happier—and diseases spread a little more easily mosquito to human.

What’s being done: Public health departments around the country are randomly testing mosquitos by collecting them in traps to give a good view of risk. If there are consistent positives, vector control units will then go to these areas and spray mosquito repellent in mass.

Is climate change making mosquito-borne illnesses worse? It depends. Diseases like Dengue are rising with climate change. But West Nile remains fairly stable. For more, check out our deep dive:

YLE Other Infectious Diseases

Don’t let mosquitos drain the last of summer fun

Katelyn Jetelina and Unbiased Science · August 29, 2024

There is a lot of news about mosquitos and diseases right now:

Read full story

How to protect yourself: Risk of disease is low, but that doesn’t make mosquitos any less annoying.

While mosquito spraying is safe for humans and pets, it can exacerbate symptoms of asthma or other respiratory conditions.

It’s a good idea to try to stay inside during the spraying time. Also, in general, cover up with protective clothing (permethrin-treated is ideal), apply EPA-registered repellents (search tool here), and use screens on windows and doors. Turn on the AC, if you have it.

Vaccine Injury Compensation Program at risk. Let’s remember why we have it in the first place.

Last week, RFK Jr. announced his plans to “change” the Vaccine Injury Compensation Program (VICP).

No medical intervention is without risk, and vaccines—while overwhelmingly safe—can rarely cause serious adverse reactions.

If that happens, you can’t sue a pharmaceutical company directly. Instead, you must file a claim through the VICP,

which was established by the National Childhood Vaccine Injury Act (NCVIA) of 1986. Since its creation, the program has paid over $5.4 billion in awards, which turns out to be ~1 individual compensated for every 1 million doses.

The VICP has long been a target for vaccine skeptics, who argue that pharmaceutical companies should be held more accountable for alleged harms and that the program should compensate claims even when there’s no clear evidence that a vaccine caused the injury.

So, what’s the problem? Eliminating this program could backfire. In the 1980s, a wave of lawsuits from parents who believed their children had been harmed by vaccines drove up legal costs and pushed many manufacturers to abandon vaccine production altogether because it didn’t make sense for their bottom line. To ensure vaccines remained available while still providing a path to compensation, Congress created this no-fault system funded by a small excise tax on each vaccine dose.

The system isn’t perfect, but it strikes a delicate balance: compensating those who are harmed while ensuring continued access to lifesaving vaccines.

Can it be improved? Absolutely. Bipartisan proposals over the years have included:

• Hiring more reviewers and improving efficiency
• Raising the maximum compensation amount (unchanged for decades)
• Automatically applying the program’s excise tax to new vaccines without requiring congressional approval

RFK Jr.’s proposals, however, remain vague, and based on his recent actions in the vaccine world, it’s likely he’s looking to dismantle the system altogether.

What does this mean for you? Nothing yet. But if the VICP were eliminated, the future availability of vaccines could be at risk. We’re watching closely.

Vaccination rates in the past year have decreased in 20 states.

CDC just released kindergarten data from last year. There’s good and bad news.

Good news: On a national level, the number of kindergartners vaccinated against diseases, like measles, is still very high: 92.5%. This is slightly lower than last year (92.7%), but I don’t think it warrants the dramatic headlines I’ve seen.

Bad news: National vaccination rates don’t tell the whole story as outbreaks tend to occur at the hyperlocal level, where local vaccination coverage determines vulnerability.

State-level trends show wide variation in coverage, with 20 states seeing declines in the past year. Idaho, for example—which has the lowest MMR rate in the country—has dropped to 78.5% (from 79.6%). (For context: the herd immunity threshold is 95% for measles and 80% for polio.)

Source: CDC; Annotated by Your Local Epidemiologist

Multiple factors drive declining vaccination rates, but one is the rise in non-medical exemptions—parents opting out for religious or philosophical reasons. While still relatively low nationally (4.4%), in some states, these exemptions are increasing at an alarming pace with no signs of that trend slowing down. In Idaho, it’s up to 15.4% of parents opting out.

Share of kindergartners with a nonmedical vaccine exemption. Source: New York Times.

What does this mean for you? Expect more outbreaks of vaccine-preventable diseases leading to school disruptions, and heightened concern for immunocompromised individuals and parents of children who are too young to be vaccinated. If you’re up to date on your vaccines, you’re well protected. But with public health infrastructure increasingly under strain, response efforts may be slower and less effective.

Training health communicators: need for a new approach

In a not-so-shameless plug: Kristen Panthagani (YLE contributor), Katelyn Jetelina (YLE) and our co-authors Ted Melnick and Megan Ranney’s perspective piece on training the next generation of health communicators was published in the New England Journal of Medicine.

The top-down model of health communication is broken—people increasingly turn to informal sources like social media and (ahem) newsletters for their health questions.

Yet scientists, doctors, and public health professionals receive little to no training on how to communicate with the masses.

We dove into this world at the beginning of the pandemic out of necessity, but largely had to figure it out on our own—with very little support (and zero training) from academic institutions.

We need more credible voices in informal spaces and that means we need to train them in how to do it. (Katelyn is teaching a course at Yale in Spring 2025!) But in short, training needs to include:

• Distinguishing information dissemination from communication.
• Communicating scientific uncertainty and managing expectations.
• Using empathetic and engaging communication strategies.
• Leveraging interactive media for effective listening.

Read the full piece here, and tune in tomorrow for a chat with lead author Kristen Panthagani on Substack Live.

Good news!

• Big reprieve: In a bipartisan win (26-3 vote), the Senate Appropriations Committee rejected the Executive Branch’s proposed massive cuts to NIH and CDC for the FY2026. Instead, it supported a $400M increase for NIH. (Note: This isn’t finalized; it still has to go through the House and be passed by October, but it’s a huge positive sign for scientific discovery and infrastructure.)
• Exercise saves lives after colon cancer: In randomized trials across 55 research centers, post-chemo exercise programs for colon cancer patients improved survival by 37% compared to health education alone.
• Medicaid ruling: A federal judge blocked cuts to Medicaid funding for Planned Parenthood. The ruling ensures that 600 health centers in 48 states, serving over 2 million patients, can continue providing care.

Trivia

It’s peak summer, and we are all sweating. I just returned from Houston (who goes to Houston in August?) and it was… hot.

Scroll down for the answer.

Bottom line

You’re all set for this week! Have a healthy, beautiful summer day.

Love, YLE

Your Local Epidemiologist (YLE) is founded and operated by Dr. Katelyn Jetelina, MPH PhD—an epidemiologist, wife. YLE is a public health newsletter that reaches over 375,000 people in more than 132 countries, with one goal: to translate the ever-evolving public health science so that people are well-equipped to make evidence-based decisions. This newsletter is free to everyone, thanks to the generous support of fellow YLE community members. To support the effort, subscribe or upgrade below: