Another mass shooter strikes, RSV surges, Ebola persists. Plus, what to know about waning flu vaccines.

Another mass shooter strikes, RSV surges, Ebola persists. Plus, what to know about waning flu vaccines.

The Dose (October 20)

Katelyn Jetelina

Oct 20

I’m back from a trip to the East Coast, and the leaves are just starting to turn. There’s just something about red and gold and bright yellow that makes everything in this world feel a little better and cozier.

This beauty, sadly, does nothing to stop the fall viruses that are stirring this week, nor a devastating public health problem: mass shootings. As a mom to two elementary school students (and epidemiologist, and human), this guts me every. single. time.

I also check in on the Ebola outbreak that quietly jumped to Kenya, share good news about scientists taking a stand, and answer your burning question: if you get your flu shot now, will it last until spring?

Here’s your “dose” of health information for the week.

Health “weather” report

All three major fall viruses are starting to stir

Nationally, the number of people feeling crummy is low but rising. But who’s sick with what depends a lot on where you live.

The West Coast is the hot spot right now, with the most tests coming back positive for both the flu and Covid-19. But the direction of those waves is opposite: flu is climbing while Covid-19 is falling. Moving eastward, levels of both viruses decline, as shown in the figure below. In the Northeast and Mid-Atlantic, Covid-19 is still the biggest contributor to viral illness, while flu is just starting to creep up.

RSV levels are extremely low but starting to stir. On the one hand, hospitalizations from RSV are still rare, though they’re starting to increase in the South. On the other hand, emergency department visits for RSV are increasing in almost every state.

Seasonal viruses tend to take turns rather than surge together. One leading theory is “viral interference”. This means that, on an individual level, fighting off one virus keeps your immune defenses on high alert for a while, making it harder for the next one to take hold. This results in population-level patterns of different peaks.

Another mass shooting at a school

A tragedy in Bend, Oregon, resulted in three children and a teacher being killed and another child and teacher seriously injured. This latest mass shooting marked another heartbreaking milestone: a 5-year-old became the youngest person killed in a school shooting since Education Week began tracking them in 2018.

As I’ve written at length before, gun violence is a public health issue: it’s predictable, and thus it’s preventable. There have been 380 mass shootings (four or more people shot, not counting the shooter) in the U.S. so far this year. That’s fewer than at the peak in 2021, but still more than one a day.

Guns remain the number one cause of death for children and teens ages 1 to 17 in the U.S., a terrible record we’ve now held for five years in a row. As devastating and shocking as mass shootings are, most of the recorded gun deaths are homicides and suicides.

There are some important nuances to keep in mind with mass shootings. I remind myself of them often as a mom trying to keep my kids safe:

1. It’s really hard to explain evil. While mental illness may play a role in some cases, it is not the cause of most gun violence. In fact, people with mental illness are more likely to be a victim. (Read more in a YLE deep dive here.)

2. This is a uniquely American problem. Other wealthy countries have mental illness, video games, and bullying, but not our access to guns. Our child and teen gun death rate is more than 9.5 times that of Canada, which has the second-highest rate among peer nations.

3. There’s a lot we can do. For parents, it’s the lowest-hanging fruit: lock up guns at home, ask about guns before playdates, and report warning signs (see something, say something). Most attackers signal their plans beforehand. (Read more in a YLE deep dive here.)

Global spotlight: Ebola outbreak marches on

While the headlines have faded, the Ebola outbreak in Central Africa has not, and last week brought a concerning update that got drowned out in the news.

Current situation: The outbreak of Bundibugyo, a particularly virulent strain of Ebola, remains concentrated in the Democratic Republic of Congo (DRC), which has recorded more than 9,000 cases and more than 4,400 deaths since the illness was officially detected in May. In fact, Ebola has just spread to an eighth province. As the graph below shows, this outbreak may well surpass the massive, record-breaking outbreak in West Africa between 2014 and 2016. This situation is the result of a perfect storm:

1. A strain of Ebola with no approved treatments or vaccines

2. The dismantling of USAID, which funded disease surveillance, outbreak training, and supplies in eastern DRC.

3. Armed conflict and deep mistrust, including attacks on burial teams and destruction of Ebola treatment centers.

Two other things stand out:

1. The death rate is clocking in at 48%. Bundibugyo has historically been less deadly than other Ebola species. That’s striking, and it shows what happens when there are no proven treatments and health care is stretched thin.

2. Ebola reached Kenya and spread there. Kenya now has eight confirmed cases, for the first time ever, all linked to one man returning from the DRC. He was sick for a month, crossed two borders, and boarded a flight to Nairobi undetected. Once there, the virus spread inside a hospital, infecting three health workers. And Nairobi’s airport is East Africa’s busiest hub. The good news: no community transmission yet, and contact tracing seems to be working. But this shows how easily the outbreak can jump.

The good news: We do have an Ebola vaccine, Ervebo, though it was designed for a different strain (Zaire), and we don’t know whether it works against Bundibugyo. But encouraging data, including lab and animal studies, suggest some cross-protection, and in the DRC, all nine people who caught Bundibugyo after receiving Ervebo survived.

So, two things are happening in the DRC. Health workers are getting Ervebo because some protection is better than none on the front line. And second, a major trial is expected to launch this week to see whether it actually works against Bundibugyo (and to what extent). Researchers will use “ring vaccination,” offering the vaccine to contacts of confirmed cases and their contacts.

Good news

• Courage in standing against the politicization of science. On Friday, the board overseeing the NIH research hospital voted unanimously to back its chair’s statement accusing Health Secretary Robert F. Kennedy Jr. of undermining trust in science and politicizing the hospital’s work after he launched a vaccine injury clinic. Studying rare side effects is necessary, but the research only helps if it doesn't confirm a preset conclusion. I deeply appreciate the scientists and leaders on the inside still protecting the integrity of science for all. (Source: NYT)

• Guidance for menopause. For the first time since 2014, the American College of Obstetricians and Gynecologists updated its guidelines for treating menopause symptoms. It now recommends working closely with your physician on hormone therapy for hot flashes, night sweats, and the sleep problems they cause, ideally started before age 60 or within 10 years of the start of natural menopause. For women who can’t or don’t want to use hormones, the guidelines also highlight non-hormonal options.

Question grab bag

In the YLE “preparing for sick season” series, we keep getting these questions: Doesn’t the flu vaccine wane? If I get it early this season, will it last until spring?

Flu vaccine protection does fade over time, but for most people, it shouldn’t change your plans.

A recent review from Canada pooled data from more than 49 studies and found that vaccine effectiveness does decline over the season, especially in people over 65. This is because our immune systems respond less strongly to vaccines as we age. But importantly, protection doesn’t disappear.

To show what this looks like by age, I made some graphs using another study (below). The first graph shows kids’ protection during the 2023–2024 season barely changing. This contrasts with adults over 65 (third graph), whose protection dropped noticeably.

The goal is to have the strongest protection when the flu is at its worst, which is usually in fall. With flu activity starting to rise now, this is a great time to get vaccinated.

Bottom line

Like the leaves, the season is changing. Viruses are rising, so get vaccinated. Gun violence remains preventable, so lock it up and speak up. And Ebola is a reminder that global health is our health.

Love, YLE

A big thanks to Dr. Craig Spencer, global health epidemiologist, physician, and Ebola survivor, for reviewing the Ebola section to ensure you have the most up-to-date information!

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