Your Local Epidemiologist
@ylepidemiologist
👩🏻🔬 Simplifying public health with data-driven insights 💡 Helping you make informed health decisions 🎓 MPH, PhD 👇🏻 Get weekly science-backed updates
8/ Finally, something I’ve been thinking about after a recent panel. Pastor Floyd Thompkins, from Marin City, and I were invited to describe how we—as a pastor in a mainly African American community, and as the local public health officer—navigated hard conversations through the Covid-19 pandemic.
7/ Now, Covid-19. After months of “very low” wastewater levels, California has moved into the “low” category. Summer activity is rising, and we’re at our highest levels since last fall. It’s too early to know how large this wave will be. Hospitalizations will tell us more in the coming weeks.
4/ In LA County, mosquito pools positive for West Nile are 10x higher than this time last year: 67 positive mosquito pools in 2026 vs. 6 in 2025. Statewide, 205 West Nile-positive dead birds have been reported, compared with 51 at this point last year.
2/ First, West Nile virus. California has the highest burden of West Nile in the country: more than 8,000 cases and 400+ deaths since 2003. Most infections cause no symptoms, but about 1 in 100 become neuroinvasive disease (meningitis, encephalitis, paralysis). Risk increases sharply after age 55.
9/ The iceberg lettuce recall remains active across 27 states as investigators work through complex food supply chains. If you’re in an affected state, avoid shredded iceberg lettuce.
1/ Right on cue, Covid-19 is starting to stir. Every summer, we see a bump in cases around mid-July, and this year appears to be following the same pattern. Levels of spread and infection are still very low, but they’re beginning to climb.
8/ ❓If the source is very likely Taylor farms lettuce, do we still need to avoid other produce? If you’re in one of the 27 states below, avoid all shredded iceberg lettuce.
13/ In the meantime, the practical advice is straightforward. If you live in one of the 27 states included in the recall, avoid shredded iceberg lettuce. If you're pregnant, 65+, or immunocompromised, I'd also be extra cautious around produce with lots of crevices until investigators know more.
10/ On the infectious disease front, things remain reassuring. Covid, flu, and RSV activity remain low. West Nile Virus has been detected in mosquitoes in Queens and Staten Island (which is expected for this time of year) but no human cases have been reported yet.
5/ A few other reminders: 🔹Stay hydrated and keep pets cool. 🔹Be careful around hot playground equipment and pavement. 🔹Confusion, dizziness, hot dry skin, or unconsciousness are signs of heat stroke—call 911. 🔹Check on your neighbors, relatives, or friends who may not have or use AC.
2/ First, let's take a look at the heat. A prolonged heat wave is expected to last through the Fourth of July weekend, with some calling it the hottest stretch we've seen since 2012. Heat is the deadliest weather hazard in the U.S., and unfortunately, it's becoming deadlier in New York.
10/ 6️⃣ Know the difference between heat exhaustion and heat stroke Heat exhaustion can often be treated by cooling down and rehydrating, but heat stroke is a medical emergency. If someone becomes confused, loses consciousness, or has a very high body temperature, call 911 immediately.
6/ 3️⃣ Heat risk isn't the same for everyone. Older adults, pregnant women, people with heart disease, children with asthma, outdoor workers, and people without reliable air conditioning face much higher risks. These are the people to check on first during extreme heat.
2/ 1️⃣ Don't focus on temperature alone. Humidity can make moderate temperatures far more dangerous because sweat can't evaporate as easily (your sweat evaporating is what cools your body). That's why 90°F in a humid city can pose a greater health risk than a much hotter day in a dry climate.
7/ After some digging, it looks like 2 viruses may explain some of those illnesses. Parainfluenza, which normally peaks this time of year, is circulating. Wastewater surveillance is also showing a sharp rise in parechovirus, a virus that isn't routinely tested for, so it often flies under the radar.
3/ But we're starting to see small increases in Southern states, along with a slight uptick in Covid-related emergency department visits. Historically, this is where a summer wave begins. We'll be watching closely to see whether this stays a small regional bump or grows into a broader summer wave.
8/ Finally, we're ending on one of the stranger public health stories this month, which involved a Central Park carriage horse named Deniz. According to Cornell Veterinary Hospital, the horse died after eating a lethal amount of Japanese yew, a common landscaping shrub planted throughout the U.S.
5/ Mosquito season is also getting started. With more mosquitos, expect more news of mosquito-borne illnesses, like West Nile Virus. Before anyone gets too concerned: most mosquitoes don't carry disease, and human West Nile cases remain relatively uncommon.
3/ Many of us living in NYC aren't used to doing tick checks after a picnic, walking the dog, or spending an afternoon in the park. With what we're seeing, now may be the time to start. Ticks found in the city can still carry Lyme disease, babesiosis, and anaplasmosis.
2/ First up: ticks. We're in peak tick season across the Northeast right now, and unlike last year, activity has stayed elevated for weeks. What's different this year is that ticks aren't just an "upstate hiking" problem anymore. We're seeing increasing reports of ticks in city parks and urban areas
10/ This is also bigger than this one incident. Since 2004, more than 3,900 industrial chemical releases have been reported to the EPA, including thousands that caused documented harm. Often, nearby communities bear the risks while receiving the fewest answers or protections.
3/ To put that in perspective: spending a full day outdoors in "very unhealthy" air can be comparable to smoking about half a pack of cigarettes. Thankfully, N95 masks work well against smoke particles. Air filters in your home AC units, and home air purifiers also filter out smoke particles.
2/ Here's what we know: People closest to the fire, and those downwind of the smoke, face the greatest health risks. The primary concern right now is PM2.5—tiny smoke particles that can travel deep into the lungs. Air quality readings in the area reached "very unhealthy" levels for much of the week.
2/ San Diego County just issued an advisory after detecting 14 rabies-positive bats this year. Since January 2024, bats have accounted for 642 of California's 705 confirmed animal rabies cases. Believe it or not, skunks are actually the next most common carrier in California.
1/ Rabies remains one of the deadliest infections on earth. Yet in California, almost every human case is preventable. With summer wildlife activity increasing and bats accounting for more than 90% of our animal rabies cases, here's what you need to know along with a few other public health updates👇
9/ Finally, bird flu. After months of relative quiet, the USDA reports a sharp jump in infected dairy herds: in the past 30 days, 45 tested positive in Idaho, 2 in Utah, and 1 in Texas. We’re not at 2024 levels, but this is more than we’ve seen in a while.
7/ I'm also still monitoring the Ebola outbreak in Africa, where cases have now climbed to 808. The outbreak has already surpassed what the two largest previous Ebola outbreaks recorded at the same point in their first 100 days, signaling the outbreak could become very large.
4/ Are there any specific diseases you should be concerned about? The main mosquito-borne disease in the U.S. is West Nile virus, but it remains rare. So far this year, only 13 cases have been reported nationwide.
1/ It's peak outdoor season, which means it's also peak bug season. We're in the heart of tick season across much of the U.S. Activity started earlier than usual this year but is now tracking close to previous seasons. Fortunately, we may see activity begin tapering in the coming weeks.
9/ Finally, what are fans worried about? According to YLE's weekly World Cup survey, very few people are hearing health rumors right now, which is a good sign. The biggest concerns from attendees are traffic and transportation accidents, navigating large crowds, and ICE-related concerns.