Breathing room: Inhalers for every school

Last week, Governor Newsom announced that the state will supply free emergency albuterol inhalers to every public and charter school in California. That’s over 10,000 schools, from kindergarten through high school.

This program can help solve an important problem. Albuterol relaxes tight airways within minutes, and is a mainstay of asthma treatment. About 1 million kids statewide have asthma, and among those with active symptoms, 1 in 3 miss at least a week of school every year. Asthma is one of the leading drivers of school absenteeism in the state.

What was the policy before? The default has been to bring your own inhaler. A kid with diagnosed asthma could carry and self-administer their own inhaler if a parent filed the paperwork. But without a prescription, or if it was forgotten that day, the school often had nothing to give them. For school staff, options were to call parents to bring an inhaler, or call 911.

California’s standing order already made it legal for schools to stock albuterol for any student — but adoption was voluntary, and sourcing the drug, training staff, and managing supply fell on each district’s own budget. So access depended on which school a kid happened to attend. What CalRx changes it’s making this free and universal.

What is CalRx?

CalRx® uses the state’s purchasing power — as the world’s fifth-largest economy — to negotiate down the cost of essential medications. The focus has been on a short list of life saving medications. Since the Governor’s first executive order in 2019 CalRx has rolled out biosimilar insulin (around $55 for a five-pack of pens) and over-the-counter naloxone at $24 a twin-pack, which helped push generic naloxone prices down 22 percent statewide within a quarter. Albuterol is the third drug under this model.

The state is partnering with the California School Nurses Organization to provide asthma and albuterol trainings to school districts for free. If you’re a school administrator, you can request trainings and free albuterol here.

My take. As a dad with three kids with asthma, I know how painful it is to sit by while a child works to get air because they don’t have an inhaler on hand. Too often, that’s the position kids and school staff have been in. My kids used their inhalers at school regularly, usually after running around at recess. Other kids haven’t always had that kind of support, and end up sitting out activities, or left without a solution if their airways tighten. This is partly a matter of health equity.

This is a three-year commitment— after that, schools will have to start paying (at a discounted CalRx rate). Still, for a condition as serious and scary for a child as asthma, putting the right medication in every building — free, with no prescription required — is a public health win.

Covid-19 climbing state-wide

Covid-19 activity continues to rise in California, and we’re seeing impacts in emergency departments and hospitals. In the week ending August 15, each day 55 people on average were hospitalized with Covid-19 statewide. Hospitalization rates are steadily increasing.

Virus levels in California are moderate in the national wastewater surveillance system, and are more than double national levels. This past winter, our readings were less than half national levels—another winter-light, summer-heavy year for California.

Covid-19 wastewater levels: National, Regional, and California, 2026

All California regions are seeing increased virus activity, with the greatest rise in the central part of the state.

Covid-19 test positivity, by region

Test positivity rates have doubled in the past month, and are in the high or moderate level in all regions. Statewide, about one in ten tests for respiratory illness are now positive for Covid-19, up from about one in twenty tests a month ago.

Vaccinations. If you’re at elevated risk for a serious outcome if you’re infected, and its been more than 6 months since your last shot, I still recommend you get the vaccine now.

The California Department of Public Heath has recommended that all healthcare providers and pharmacies continue to administer the 2025-2026 Covid-19 vaccine through the summer, while awaiting arrival of the 2026-2027 vaccine later this year. We still don’t have exact timing. I’m hearing mid-September.

Covid-19 vaccines can be given during the same visit as other vaccines. Visiting MyTurn.ca.gov, or contacting your local pharmacy or health care provider. YLE National shared a Fall Vaccine Guide this week. It’s a great reference for planning your personal schedule.

West Nile virus update

West Nile virus (WNV) cases continue to rise quickly. Here’s how the numbers have changed since my last WNV update. Since August 13:

• Human cases: 18 → 46 (14 counties), including four deaths in Butte, Yolo, Kings, and Fresno counties.

• Dead birds: 330 → 437.

• Mosquito samples: 1,890 → 2644.

• Sentinel chickens: 16 → 64.

• Horses: 4→ 6.

Forty six human WNV cases is more than three times the number at this time last year. The national case count climbed from 181 (August 11) to 299 (August 25), the highest in 20 years.

West Nile virus human cases compared to previous years, California

Higher risk groups: Some people have a higher chance of getting sick, developing neurological complications, or even dying from WNV. Risk factors include being 60 or older; having diabetes, hypertension, or chronic kidney disease; or being on medication that suppresses your immune system.

It’s never clear if a rapid rise in cases spells a worse year overall. In any infectious disease, “velocity” of a surge doesn’t always predict the long-term pattern. Sometimes surges rise fast and drop just as quickly.

What you can do:

• Report dead birds. Call 1-877-WNV-BIRD (1-877-968-2473)—they’ll decide whether to send someone to retrieve and test the bird.

• Prevent bites. Dump standing water around your home at least weekly (flowerpots, pet bowls, old tires, anything that collects rain or hose runoff), make sure screens are intact, and use an EPA-registered repellent during dawn and dusk, when Culex mosquitoes—the species that carries WNV—are most active. There’s no vaccine and no treatment for WNV, so avoiding the bite is the best protection.

Bottom line

That’s it! Be well, and I’ll see you next week.

Love,

Matt

Dr. Matt Willis is the author of Your Local Epidemiologist in California. A California native, he’s served as a primary care physician, CDC epidemiologist, and public health officer for Marin County, where he guided the pandemic response. He lives in Marin with his family and their dogs, Teddy and Ramona.

For public health, the e-bike boom is a healthy trend. But the question of how to protect young riders is still up in the air, and is a matter of public debate. Here’s how I’m making sense of it all.

Are e-bike accidents increasing?

Yes—but with a ray of hope I’ll describe later. With increased e-bike use we’re seeing more e-bike related injuries. In 2018 California Highway Patrol logged just two e-bike crashes, compared to 1,506 in 2024. Hospitals across the state are seeing more e-bike injuries, including Rady Children’s Health in Orange County.

Policy scramble: Here’s the challenge. E-bikes really hit the market around the start of the pandemic, before regulation, safety standards, or basic data collection could keep up. The past four or so years have seen a rush to catch up on two fronts—measuring the problem, and legislating around it. I’ve had a front row seat to both of those issues.

An e-bike microcosm for the state. Marin County, where I was health officer, ended up in the middle of that scramble. Even by California standards, our community adopted e-bikes early, making us a canary in the e-bike coal mine.

In 2023, I remember the first signal came from our ED doctors, who were seeing people in bike crashes with injuries they’d expect from motorcycle accidents—pelvis and femur fractures, internal organ damage.

To really understand the local problem, Marin Public Health built a bicycle safety dashboard, pulling live ambulance data to track crashes by bike type, age, and outcome. We weren’t collecting data for long before a pattern emerged.

In fall 2024, after 50 days of tracking 911 responses, we found that school-aged kids aged 10-19 had a 5 times higher rate of e-bike accidents than any other age group. We were shocked, and issued a local public health alert. Youth e-bike safety became a county-wide priority.

Focus on youth

The extra risk young people face has defined the e-bike problem in California. The immediate response has understandably been a call for solutions. But, when we look more closely, the picture gets complicated. “E-bike” is a catch-all for several different vehicles—and it matters which we’re talking about when we consider policy.

Here are the classes of e-bikes sold in California, and their main features. From Class 1 to e-motos they get further from a regular pedal bike in look, function, and power.

Early e-bike policy results in California. Ultimately Marin became a “laboratory” to assess the impact of a policy solution, as a one-county pilot. In 2024 state Assembly Bill 1778 authorized Marin to limit e-bike use for riders under 16 to Class 1 e-bikes—the pedal style e-bikes most like an ordinary bicycle—and bar them from Class 2 throttle models. (Class 3 and e-motos were already illegal for people under age 16.) This was the state’s first law to place new age restrictions on e-bike use.

Results at one year. AB 1778 went into effect in July 2025, so we just got the first year’s results last week. Preliminary data are promising: the youth e-bike injury rate dropped from 16 to 12 per 10,000 county residents in the year after the ordinance took effect. It’s not proof of a sustained trend, but it’s a real signal. Helmet use among accident victims also increased from 77% to 90% during the same interval.

It’s hard to tease out the factors behind declining e-bike accidents in Marin but the Mineta Transportation Institute 2025 report offers some insights. They found that e-motos—illegal, over-powered devices—are a key driver of California’s e-bike safety problem.

A 2024 count of e-bikes parked at Marin and San Mateo County middle schools found that nearly 9 in 10 were illegal e-bikes or e-motos. Decreasing e-moto use under AB 1778 could help explain a reduction in 911-level e-bike accidents, because they are heavier, faster, and more risky.

What are e-motos, and are they the problem?

E-motos aren’t bikes at all. Most have no pedals and have top speeds of 30-50+ mph, putting them closer to a motorcycle than anything a kid should be riding to school. Legally, an e-moto rider needs to be 16 with a valid license, registration, and insurance. But almost none of that gets enforced, and e-motos are sold, gifted, and ridden as if they’re just a faster bike. They read as e-bikes, and are popular with middle schoolers.

Typical e-moto

Speed matters. Injuries that happen above 20 mph—the ceiling for Class 1 e-bikes—are far more severe than those below it: a study of 15,121 pediatric e-bike injury patients found that half of higher speed accidents involve head, neck, or facial trauma versus 29% for slower crashes, and internal organ injuries occur at more than double the rate. At 30 to 50+ mph, e-motos routinely travel way above the threshold where injury severity doubles. The same study found 79.7% of e-bike accidents involved a male rider.

Gaining focus. We’re seeing a picture emerge, a risk profile, for common e-bike accident scenarios in California. This lends focus to our policy direction. Limiting access to e-motos, encouraging Class 1 e-bikes, enforcing helmet laws, and providing education on rules of the road will go a long way. And making sure our boys are paying special attention.

Here are some tips for families considering an e-bike:

• Get informed. Parents and teens should take time to understand the different classes of e-bikes and the laws in their community. And remember e-motos are unsafe and illegal for anyone under age 16.

• Consider taking a class. Many law enforcement agencies in California now offer hands-on e-bike safety courses specifically for teens. The California Highway Patrol has a great on line training.

• Wear a helmet. A properly fitted and buckled helmet is one of the best ways to reduce the risk of head injury.

• Think about age. Most pediatric groups agree that children under 12 should not be riding e-bikes due to speed, size, and handling challenges.

• Do not modify e-bikes. Altering an e-bike can increase speed to unsafe levels and change how it is classified under the law.

• Choose your route. Stick to physically protected bike lanes when possible, especially for beginners. Painted lanes on busy streets require more experience, and sidewalks aren't a safer alternative.

Sidebar: It’s not just about the bike. A safe ride to school depends on more than being on the right bike— we need safe routes, drivers who can share the road, help at key intersections, and a community that’s supportive. That’s culture change, and it takes time.

As e-bike use grows, the state’s Climate Action Plan for Transportation Infrastructure directs more than $5 billion a year to climate and safety goals, with safe bicycle and pedestrian networks as a priority.

Grassroots efforts like Safe Routes to School gives parents, schools, and local law enforcement a place to come together, share what they’re seeing, and push for the changes their community needs.

Bottom line

The path toward safer e-bike use for young people in California is getting clearer as we learn more about what’s driving accidents, who’s most impacted, and which policy solutions might work. It’s been rewarding to be part of that learning. We still have along way to go.

If I have any concerns about framing e-bike injuries as a public health crisis, it’s the shadow it may cast on biking itself. Getting more of us on bikes is a major public health win.

None of this is an argument against e-bikes. They’re cheaper than a car, way better for a kid’s health than a back seat, fun, and better for the environment.

As we get back to school, the message is still to try to get on a bike— in the right class, on friendly streets, at the right age, with a helmet. At least make sure it’s not actually a motorcycle.

Love,

Matt

P.S. Here are some popular California e-bike routes for longer rides. Maybe I’ll see you out there!

• San Francisco Bay Trail: 500+ miles, Class 1 & 2 allowed on most sections.

• American River Bike Trail: 32 miles, commonly Class 1 only.

• The Strand (LA): 22-mile beach path, Class 1 & 2 (check specific city segments).

• San Diego Bayshore Bikeway: 24 miles, most sections allow all classes.

• Angels Camp/Arnold Trail: 12-mile rail-trail, local rules apply.

In case you missed it: Read my piece on wildfire smoke in this week’s YLE National.

Your Local Epidemiologist

When wildfire smoke hits home

Wildfires have been all over the news, not just in the U.S. but in Europe as well, where I (Katelyn) have been. For Matt Willis, the author of YLE California edition, it just became very personal. I’ll let him explain…

Read more

14 days ago · 469 likes · 43 comments · Matt Willis

Dr. Matt Willis is the author of Your Local Epidemiologist in California. A California native, he’s served as a primary care physician, CDC epidemiologist, and public health officer for Marin County, where he guided the pandemic response. He lives in Marin with his family and their dogs, Teddy and Ramona.

Covid-19 illnesses are ramping up

After watching Covid-19 activity rise in wastewater through July, we’re seeing impacts in emergency departments and hospitals. In the last week of July, an average of 33 people were hospitalized with Covid-19 per day statewide. Hospitalizations have been steadily increasing, and are projected to reach over 70 daily Covid-19 admissions by the end of the month.

Virus levels in California have been upgraded from low to moderate in the national wastewater surveillance system (NWSS).

Covid-19 wastewater levels: California, August 2025 to now

All California regions are seeing surges in virus activity, with the greatest rise in the central part of the state.

Where are the 2026-2027 fall Covid-19 vaccines? I’ve been looking for any sign of when the new vaccine will hit the market, and it’s been crickets.

This silence may be related to the uncertainty manufacturers feel this year. ACIP, the body that turns FDA approval into an actual recommendation, hasn’t met since December. ACIP was sued based on a lack of scientific basis for their changes to the childhood vaccine schedule, and won’t meet again until October 21–23.

The August 10 presidential executive order reinforced that the Covid-19 vaccine was dropped from the universal recommendation list for kids and pregnant women, and legal pushback is expected. So it’s kind of a mess at the federal level, and that has a chilling effect on vaccine roll outs. I expect we’ll know more by the end of the month.

Should you get vaccinated now? I recommend that if you’re at risk for more serious illness, go with the bird in hand and get the current vaccine. The likelihood of being exposed when you’re out and about is rising daily. You can find a shot near where you live in California at MyTurn.

Masks: We’re going to see more people using masks out there, and that’s a good thing. These days mask choices are about personal protection, and a well fitted N-95 type mask is highly protective against infection.

For anyone at higher risk for serious disease, or if you’re really focused on not getting Covid-19, its a good time to brush off the mask and consider wearing it in indoor public spaces when the virus is circulating at high levels. For me, we’re not there yet, but I’ll continue to provide updates on virus activity to guide your decisions.

West Nile virus update

West Nile virus numbers are rising fast, and California has now recorded its first deaths of the season.

Here’s how the numbers have changes since my last WNV post. Since July 26:

• Human cases: 5 → 18 (11 counties) — including two deaths, in King and Glenn counties. This was Glenn county’s first WNV death ever. New first cases for this season were reported in Glenn, Kern, Riverside, and San Joaquin counties.

• Dead birds: 251 → 330 (20 counties).

• Mosquito samples: 1,001 → 1,890 (27 counties)

• Sentinel chickens: 2 → 16 (6 counties), including a first detection in Colusa County.

• Horses: 1 → 4 (4 counties), including a first case in Merced County.

This map shows WNV activity in California, calling out the counties where first detections in humans or animals happened between July 26 and October 7.

18 WNV cases is more than twice the average for this time of year in California—peak season is still ahead of us. The national case count has climbed from 91 (July 21) to 181 (August 11), the highest in 20 years.

California is one of five states with elevated WNV activity.

Why is this a severe year for WNV? There’s no formula for predicting year to year variability in West Nile burden. But temperature plays a major role.

This past winter and spring in California were among the hottest on record. Normally, in colder winter months, a fraction of mosquito populations die off. This year more made it through the warmer winter—and into a record hot spring. Higher temperatures accelerate reproduction for both mosquitoes and West Nile virus. The warming climate contributes to the burden of West Nile virus in California.

Sentinel chickens. In the last two weeks, WNV detection in sentinel chickens jumped from 2 to 16. It’s worth describing what a sentinel chicken actually is. I see them as unsung surveillance heroes. They’re out there right now, stationed in coops strategically placed around the state, getting bitten by whatever mosquitoes happens by. They’re naturally immune to WNV, and build antibodies after being infected. Local vector control workers draw a bit of chicken blood every week or two to see what’s shown up. They’re an inexpensive, low tech and critical part of our infectious disease intelligence system.

What you can do:

• Report dead birds. Call 1-877-WNV-BIRD (1-877-968-2473)—they’ll decide whether to send someone to retrieve and test the bird.

• Prevent bites. Dump standing water around your home at least weekly (flowerpots, pet bowls, old tires, anything that collects rain or hose runoff), make sure screens are intact, and use an EPA-registered repellent during dawn and dusk, when Culex mosquitoes—the species that carries WNV—are most active. There’s no vaccine and no treatment for WNV, so avoiding the bite is the best protection.

California’s vaccine firewall

On Monday, President Trump signed an executive order that recommends immunizations for 11 diseases, down from the 18 the CDC recommended in 2024. Vaccines against RSV and hepatitis A and B would shift from universal recommendation to something offered only to higher-risk kids, and the order calls for the combined MMR shot to be split into three separate injections given at separate visits.

Does the presidential EO matter? I’d love to ignore it, because these presidential guest appearances into the world of science are predictably unscientific, designed to get attention, and carry less practical relevance for us in California (more on that later). And an executive order isn’t even the legal mechanism to impact vaccine policy in the U.S.—this one is already being challenged. But it’s not benign.

Once again, this roils the national vaccine waters and leaves people feeling confused about what it all means— just as we’re preparing to get our kids back to school. So here’s what to know about this week’s executive order.

First, this is not new rhetoric. The president is just putting more ink behind the changes RFK Jr announced months ago — disruptions that are intended to unravel the U.S. childhood vaccine schedule. Those changes were challenged by the American Academy of Pediatrics, and have not gone into effect as the lawsuit unfolds. The EO does not change that.

Second, the EO is not feasible, even if it were good science. (It isn’t.) The divided MMR vaccine doesn’t exist in the U.S.—it wasn’t manufactured and distributed in the U.S. because it makes too much sense, practically, economically, and scientifically to be protected against three terrible diseases with one shot.

Third, the EO does not change California’s immunization recommendations or school and child care vaccination requirements.

Last, and most important, California saw this coming and built protections.
Last year, when it became clear the federal science steering wheel was in reckless hands, California moved fast to get some distance.

In September the governor signed AB 144, a bill to insulate us from eroding federal health standards. AB 144 locks in, as a floor, the preventive-care and immunization recommendations that were in effect on January 1, 2025—before RFK Jr.’s vaccine overhaul.

Health plans in California must keep covering vaccines, without any new disruptions—no cost-sharing, and no extra paper work or permissions. That extends to Medi-Cal, which can cover childhood vaccines outside the federal Vaccines for Children program for lower income families.

Regional support. California also joined the West Coast Health Alliance, with Oregon, Washington, and Hawaii, to hold solid, science-based regional standards. Across the West Coast, instead of being stuck with federal recommendations, our vaccine access is tied to the guidance of the American Academy of Pediatrics, the American College of Obstetricians and Gynecologists, and the American Academy of Family Physicians. All of which reliably stick to the science, and focus on what’s best for their patients.

So what does a California family need to know before school starts?

Nothing has changed. The same vaccines, in the same formulations, on the same schedule, are still recommended for California kids. Access hasn’t budged—not through your pediatrician, not through your insurance, not through Medi-Cal. Because AB 144 already grounds us in a pre-RFK Jr. baseline, and in the professional societies’ evidence-based guidance.

We’re benefiting from state public health and elected leaders who read the moment a year ago. While the federal vaccine conversation lurches from lawsuit to lawsuit, California families can tune it out and get the shots they need.

Bottom line

That’s it for this week! Next week we’ll focus on getting kids safely back in school.

Love,

Matt

Dr. Matt Willis is the author of Your Local Epidemiologist in California. A California native, he’s served as a primary care physician, CDC epidemiologist, and public health officer for Marin County, where he guided the pandemic response. He lives in Marin with his family and their dogs Teddy and Ramona.

A special thanks to Emely Bonilla, Masters in Public Health candidate at UC Berkeley and summer intern at YLE, for her contributions to today’s edition.

Katelyn (Your Local Epidemiologist) and I decided to give it a year, and than ask two questions: is the newsletter valuable to you, and is it sustainable. We knew we’d learn a lot, and that it wouldn’t be easy to build a community and audience in this saturated information landscape.

Value: This question isn’t mine to answer, it yours. It’s been reassuring to watch the numbers rise week to week— we’ve grown to over 30,000 subscribers, and about 100,000 followers. We’re a Substack best seller.

But YLE is more about quality than quantity. Our goal is to build an engaged community-- and your messages, comments, and emails tell me we’re meeting a need for information you can use. Thats the kind of value we’re looking for. That’s way more important than the numbers. Those exchanges also taught me how I can better support you.

Four lessons I’ve learned from you

Jump in early. When a new public health problem is first emerging – think hantavirus, or cyclospora, another Covid-19 wave– things are usually uncertain, facts and rumors are entangled, and the media is usually taking the ball and running. It can be confusing and alarming. Sometimes I’m not sure when to enter those waters with a post, because it’s impossible to be first on the scene and be certain.

I tend to jump in early, and you’ve assured me you see that as valuable, and as a YLE CA sweet spot. To step back and take a breath, to see what we do and don’t know, what to keep an eye on, and what you can do to stay safe. All from the California angle. I have the freedom to do that, trusting you know we’re learning as we go, and that guidance may change.

Be brave: You’ve taught me to be a brutally honest scientist. For years I wrote policy documents— cautious, distant, slow, top-down— from inside government. There wasn’t much room for first-person, for opinion, for “I’m not sure yet.” YLE CA lets me bring my expertise in my own voice: to say what I think, to be transparent about where the evidence is thin, to write from curiosity, and bring you along.

Keep the mix. I’ve covered over 200 topics in 60 posts. I wasn’t sure if that was going to be too broad, but I’ve heard you appreciate the range. One way I pick topics is to think “What’s happening right now in California that can impact our health, and what information would be most helpful to the YLE community?” That explains why you find updates on outbreaks and wildfires next to healthcare access changes and breakthroughs in science. I also sprinkle in some good news, and celebrate those working on the front lines.

Place matters: You’ve been clear you value the state focus. I feel lucky to write for the state I know and love, and I see where we’re really our own health ecosystem. California has become a leader in the fight against federal attacks on public health and science. For every national story, from outbreaks to health policy changes, there’s a California version— and ours is often different in very good ways. Higher vaccination rates have meant fewer measles cases. State lawmakers sue to block federal funding cuts. New state laws break ties to faltering federal agencies.

Of course our state health system could be a lot better, within what our leaders have control over. I’m not afraid to call that out, and elevate opportunities for change. We have policymakers who actually read this stuff, and a public engaged enough to argue back. That’s made writing about public health here as exciting as it was to practice it.

Ask

We need your help. I wanted to use this anniversary to tell you what this year has taught me, to thank you for being a part of this community, and to ask you for your help. It’s still a leap of faith, but one that’s worth it. As a public health guy, I’m used to making decisions when things are uncertain. But in order to continue to do the work I love, YLE CA needs more financial certainty.

I’m never comfortable asking for financial support, but none of this works without it. The kind of independent, accountable science communication I do takes time to do well, and it’s gotten harder to sustain. This newsletter is funded by paid subscribers. While subscriptions are growing, we need more paid subscribers to keep the lights on at YLE CA. Please upgrade below.

Bottom line

This is different work than anything I’ve done before. After years as a physician, an epidemiologist, and a health officer, being a health communicator helps integrate those chapters. Bringing that history and perspective together has been incredibly rewarding.

One of the best surprises of this year was seeing that the kind of relationship I had with patients, and with my community as health officer, extended to YLE CA, with people I mostly can’t see. The connections are real, and have helped us through some dark days for public health and science.

In my first post I promised “science-based health guidance that you can use”. I’ve been learning from you what that looks like. As we start into year two, I’m renewing that promise. Thank you for spending a year with me, and I hope you can help make the next one possible.

Love,

Matt

Dr. Matt Willis is the author of Your Local Epidemiologist in California. A California native, he’s served as a primary care physician, CDC epidemiologist, and public health officer for Marin County, where he guided the pandemic response. He lives in Marin with his family and their dogs Teddy and Ramona.

This spring, we launched The Pulse, a weekly survey sent to people across the state to hear what health questions, concerns, and priorities are on your minds. We’ve been learning a lot.

In today’s edition, Hannah Totte, who runs the survey, recaps three important takeaways from summer. Take it away, Hannah!

Summer’s winding down, but all season long, we’ve gotten questions on sunscreen, bug spray, and protein. So we dug into the research and pulled together answers for you.

There’s still plenty of warm weather left to put this to use—and the takeaways carry well past Labor Day, too.

1. Sunscreen

Sunscreen had a big moment this summer when the FDA approved a new sunscreen ingredient for the first time in 25 years. Bemotrizinol, or BEMT, has been used in other countries across Asia and Europe since the late 1990s.

We asked YLE subscribers and The Pulse respondents about sunscreen in June. We heard questions about how ingredients compare and confusion about why U.S. products differ from those in other countries.

Let’s review how BEMT changes the landscape.

• Sunlight carries two main types of ultraviolet (UV) radiation that can damage our skin—UVA and UVB. Not all sunscreens cover both. BEMT absorbs UVA and UVB rays, like zinc oxide. Unlike zinc oxide, it does not leave a white cast on the skin, which might encourage people to apply enough of it. People frequently under-apply zinc sunscreens because of the white cast.

• Many sunscreen products combine ingredients to cover both UVA and UVB radiation. Avobenzone absorbs primarily UVA rays, octinoxate primarily UVB, and oxybenzone blocks UVB plus some UVA. Over a few hours of use, the compounds start to break down, and manufacturers often add a third ingredient to stabilize them to extend protection.

• While zinc oxide has the highest stability after sun exposure, BEMT is more stable than the other three common sunscreen chemicals. This means that, like zinc, BEMT can absorb UV rays at full strength for longer before degrading and losing efficacy when exposed to sunlight. But note: you still need to reapply it every two hours.

Will the FDA approve other sunscreen ingredients?

It’s possible due to a legislative change in November 2025. Sunscreen ingredients had been backlogged in the FDA approval process, which also required them to undergo the same rigorous clinical trials and pharmaceutical-style testing as any other drug. (By contrast, sunscreen ingredients are classified as cosmetics in Europe.)

In November 2025, the bipartisan SAFE Sunscreen Standards Act was passed. This law allows for real-world data review, which helped BEMT overcome hurdles to approval. There are other ingredients used in Europe and Asia that might make it to the U.S., such as bisoctrizole and drometrizole.

But sunscreen’s not all we’re putting on our skin this summer. Next up: bug spray.

2. Bug spray

We at YLE have written plenty about diseases that mosquitoes or ticks can carry, and most of it focuses on preventing bites. We’ve gotten good questions about bug spray.

We wrote about mosquito spraying as a way to prevent the spread of insect-borne diseases, like West Nile virus, in our environment. Bug spray is also recommended as a personal protective measure against mosquitoes. But in The Pulse, we learned that about a third of respondents use nothing at all to protect themselves against mosquito bites. 62% of respondents had heard general safety concerns about DEET, one of the most common and recommended bug repellents. These included concerns about hormone disruption, toxicity, and just general unease.

Back up. What exactly is bug spray, and how does it work?

Bug spray acts as a repellent by creating a barrier on the skin that prevents your scent from attracting mosquitoes (and other bugs). Picaridin and DEET actually act on the mosquito’s protein receptor that binds smells. Oil of eucalyptus masks your scent by offering another, more intense one. All basically interfere with the mosquito’s ability to detect you.

Are there any real safety concerns with DEET or other repellents?

DEET has been successfully used as an insect repellent for over 50 years by billions of people. Mosquitoes detect humans mostly through the CO2 and lactic acid we produce, and DEET is thought to work by interfering with their ability to detect it. Despite its extensive use, there isn’t any convincing evidence of toxicity in humans or animals when it is used as directed.

There have been reports that people with a rare enzyme deficiency (ornithine transcarbamylase deficiency) can develop high levels of ammonia in their body with DEET exposure, but this still requires significantly higher doses than are recommended. DEET can cause some discomfort if inhaled or sprayed into the eyes, but otherwise there are no significant safety risks with appropriate use. (Note: DEET has nothing to do with DDT, which was an unsafe insecticide banned in the U.S. in 1972.)

When deciding whether to use repellents like DEET, remember — especially as we see upward trends in West Nile virus and other mosquito-borne diseases — the risks of mosquito bites are preventable.

3. Protein

Protein—a summer picnic must-have. Beyond cold cuts and hot dogs, protein has been getting a lot of attention lately, as a macronutrients that we can’t seem to get enough of. The Pulse respondents asked some excellent questions that we relayed to Megan, our nutrition expert. Take it away, Megan!

Is this all marketing, or are we really not eating enough protein?

A little bit of both. Some of the protein hype is undoubtedly marketing, but some of it also reflects an evolving science. Most Americans already meet the current Recommended Dietary Allowance (RDA) for protein (0.8 g/kg/day, or ~55 grams per day for someone who weighs 150 pounds). However, the RDA was designed to prevent deficiency, not necessarily to optimize health.

A growing body of research shows that some groups—older adults, physically active people, and those trying to preserve muscle during weight loss—may benefit from higher protein intakes (1.2-1.6 g/kg/day) to support health, function, and healthy aging. For a 150-pound person, that may look more like ~80–110 grams per day. So, there is some validity to the shifting conversation from “How much is enough?” to “How much best supports health and quality of life?”

But more protein is not necessarily better. Once protein needs are met, any excess is used for energy or stored as fat. While higher-protein diets increase the amount of work the kidneys do, research suggests they don’t harm kidney function in most healthy people.

Is more protein absorbed with certain foods?

Yes. Protein quality varies by food source and is influenced by its amino acid composition and digestibility.

While food companies are increasingly adding protein to surprising products like pastries, chips, sodas, and even alcoholic beverages, I wouldn’t rely on those products to meet protein needs.

The bigger nutrition gap for most Americans isn’t protein quality… It’s overall diet quality. This means focusing on incorporating a variety of nutritious protein sources throughout the day, including plant-based options such as beans, lentils, tofu, nuts, or seeds.

Is some deli meat really classified as a carcinogen (a known cancer-causing agent)?

Yes. Most deli meats are considered processed meats, and processed meat is classified by the International Agency for Research on Cancer (IARC) as a Group 1 carcinogen, meaning there is “sufficient evidence” that it can cause cancer in humans, particularly colorectal cancer. The evidence comes from more than 800 epidemiological studies that IARC’s working group reviewed. Large studies tracked people’s diets and cancer outcomes over years, and consistently found that the more processed meat people eat, the higher their risk of colorectal cancer.

Importantly, “Group 1” status reflects the strength of the evidence, not the size of the risk. We don’t yet know exactly why processed meats increase cancer risk, but potential contributors include:

• Nitrites and nitrates

• Smoking and high-temperature processing methods

• Compounds such as heme iron in red meat

“Uncured” meats preserved with celery powder are not necessarily safer, as celery naturally contains nitrates that can form similar compounds.

If deli meat is an occasional convenience in an otherwise balanced diet, I wouldn’t panic. If it’s a daily staple or if you have a personal or family history of colorectal cancer, it may be worth rotating in options like sliced chicken or turkey, tuna, or hummus.

From a big-picture perspective, factors like overall diet quality, fiber intake, physical activity, alcohol and smoking, and disease screening have a much greater impact on long-term health than any single food.

Bottom line

Summer is in full swing, and so are questions about those beach bag essentials. We’re grateful to our Pulse respondents, who guide our messaging and ensure we’re answering the questions that matter most to you. We hope this helps you stay safe and informed through the remaining days of summer and beyond.

Love, Hannah

Hannah Totte, MPH, is an epidemiologist and YLE Community Manager. She lives in Los Angeles and runs The Pulse. Megan Maisano, MS, RDN, is a registered dietitian nutritionist. During the day, Megan works at National Dairy Council, a non-profit dairy nutrition research and education organization. (She does not write about the dairy industry for YLE.)

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