Your Local Epidemiologist

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10/ Finally, this month is YLE California's 6 month anniversary. This community has meant more to me than you know. If you have 3–5 minutes, I’d love your feedback so I can keep doing this better. surveymonkey.com/r/yleca

Love,
Matt
Your Local Epidemiologist in California

9/ If you're curious why Covid is currently so quiet, last summer’s severe surge left many of us with lingering immunity. We saw a similar pattern last year with a rough summer, followed by a milder winter.

8/ Finally, let's quickly check in on the other infectious diseases. ED visits & hospitalizations remain elevated for flu, but it may be plateauing. RSV is up, especially in the Bay Area, but may be nearing its peak. Covid is still very low in California—lower than we’ve ever seen this time of year

7/ What you can do:
🔹Check your child’s MMR status
🔹Get caught up if needed. It’s never too late!
🔹Travel safely. Babies 6 months and older can get their first dose early if international travel is planned.
🔹Find free or low-cost vaccines at MyTurn.ca.gov

6/ But that protection is fragile. Three converging risks worry me:
🔹A small but real decline in coverage
🔹Pockets of very low vaccination rates (in 5 CA counties, fewer than 90% of kindergarteners are vaccinated)
🔹Rising measles activity nationally, which means more travel-related cases

5/ So far, I'm happy to report that our defenses are holding.

Last year, all 25 California measles cases were travel-related and none sparked a local outbreak because most California communities maintain ~95% measles vaccination coverage.

4/ Turning to infectious diseases: California's protection against measles outbreaks is being tested. Three cases have already been reported this year. Napa County confirmed its first case since 2012 in an unvaccinated child who had traveled out of state.

3/ One thing public health teaches us is that despair shrinks when we connect and act. I’ve been grounding myself by showing up locally and channeling concern into something tangible.

If you’re looking for ideas:
🔹californiavolunteers.ca.gov/join-californiansforall/
🔹standwithminnesota.com

2/ What’s unfolding nationally—especially the violence and instability in Minnesota—is affecting our collective mental and social health.

For me, it’s a persistent backdrop to daily life. When I sit with it, I feel fear, anger, and sometimes despair.

1/ This week’s edition looks at a few infectious diseases in California, but I want to start with a pause.

The WHO defines health as complete physical, mental, and social well-being. By that definition, many of us are not okay right now. 👇

Your Local Epidemiologist | Katelyn Jetelina | Substack Providing a direct line of "translated" public health science to you, so you can take action for your community's health. Click to read Your Local Epidemiologist, a Substack publication with hundreds ...

9/ This week’s infectious disease report was a social media exclusive (you're in the club!), but normally we release a report in our weekly newsletter. If you'd like to receive updates like this straight to your inbox, click here 👉 yourlocalepidemiologist.substack.com

8/ Even with these declines, a lot of viruses are still circulating. It's still important to take precautions to keep yourself and others healthy, such as staying home when sick and masking in crowded indoor spaces. And if you haven’t yet, it’s not too late to get your flu or Covid vaccine!

7/ Finally, it looks like Covid-19 has peaked across all regions. Fortunately, it’s been a relatively mild season compared to the past two winters, which has been a relief amidst the record-breaking flu season we’re experiencing.

6/ Flu is still elevated across all regions, but has now decreased for three weeks straight. Trends differ across age groups, though. We’re seeing a rebound among school-aged kids with pediatric emergency department visits increasing.

5/ What does it mean to you? 96% of cases are unvaccinated. You can check the vaccination rates in your county here: abcotvdata.github.io/us-vaccination-map/

If you have a child under 12 months, a first dose of the MMR vaccine at 6 months could be an option. Talk to your pediatrician.

4/ The Pan American Health Organization will re-examine U.S. measles elimination status in April, which is lost if a strain circulates for a year. We’re on track to lose it, with ongoing outbreaks as scientists investigate whether recent Texas and South Carolina cases are linked.

3/ In the past week:
🔹South Carolina reported 89 more cases since Friday, totaling 789 cases
🔹Utah reported 9 more cases
🔹Arizona reported 23 more cases, 11 of which were associated with the current outbreak

2/ Starting with measles, the South Carolina outbreak has now surpassed last year’s West Texas outbreak. As of Tuesday, there have been 789 cases in South Carolina. West Texas totaled 762 cases. The Utah-Arizona outbreaks also continue to grow.

1/ Time for a quick infectious disease “weather report.” We're giving you a quick look at what we’re seeing right now across measles, flu-like illness, and Covid. 🧵

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Supporting families through the trauma of deportation Watch now | Guides for those providing care during immigration enforcement

9/ To help, I’ve created practical, trauma-informed guides for:
🔹Caregivers
🔹Educators
🔹Clinicians

Please print, share, post or use them however your community needs.👇

yourlocalepidemiologistny.substack.com/p/supporting-families-through-the-trauma

Love,
Your NY Epi 💙

8/ Educators, caregivers, and clinicians are often the first line of support. How schools protect student information, how clinicians handle confidentiality, and how caregivers respond to trauma can make a meaningful difference in children’s health and safety.

7/ Traumatic events like watching a parent or classmate get arrested and deported can have lasting effects on children, such as toxic stress. This prolonged stress disrupts brain development in children and increases lifelong risks for physical and mental health conditions.

6/ And unfortunately, children are especially vulnerable.

Many kids live in "mixed-status" families, and may lose access to school, meals, health care, or mental health services because families often act based on the least protected person in the household.

5/ There's also the mental health effects of all this. After a large ICE raid in Iowa, researchers found more low-birth-weight babies born to Hispanic mothers statewide in the months that followed, linked to stress. Birth weights in babies born to white mothers remained stable.

4/ Ultimately, delayed care affects everyone. In LA, patients who feared immigration authorities were about 3x more likely to delay tuberculosis care. Untreated TB is contagious and dangerous, so when care is delayed, risks spread across the whole community.

3/ To be clear, this isn't just anecdotal reports, we’ve seen this in the data. After Florida required hospitals to ask about immigration status, 66% of noncitizens reported hesitation to seek care. After a similar law in Alabama, visits to public health clinics among Latino adults dropped 25%.

2/ Everything happening right now is causing so much fear. And fear changes behavior. When people worry about immigration enforcement, they delay or avoid care, even in emergencies. That means fewer ER visits, missed treatments, and worse outcomes for conditions that are treatable when caught early.

1/ Immigration enforcement is impacting people’s health. It’s a public health issue.

ICE raids and deportations don’t only affect the people directly targeted. The health impacts ripple through families, schools, clinics, and entire communities.

Supporting families through the trauma of deportation Watch now | Guides for those providing care during immigration enforcement

9/ To help, I’ve created practical, trauma-informed guides for:
🔹Caregivers
🔹Educators
🔹Clinicians

Please print, share, post or use them however your community needs.👇

yourlocalepidemiologistny.substack.com/p/supporting-families-through-the-trauma

Love,
Your NY Epi 💙