R.S.V. Strains California Hospitals

The Covid-19 pandemic persists, we’re in the midst of flu season and now there’s a new threat to worry about: R.S.V.

Perhaps you’ve heard of the possibility of a “tripledemic,” an alarming sequel to last winter’s “twindemic” with the addition of respiratory syncytial virus, or R.S.V. It is by no means a new virus, but the number of children falling ill — and particularly the number becoming seriously ill — has climbed quickly this fall and remains significantly higher than usual across California and the U.S.

“R.S.V. has just surged: We keep thinking it’s peaked, but then it keeps on going up,” said Dr. Tami Hendriksz, a pediatrician and the dean of Touro University’s College of Osteopathic Medicine in Vallejo. “We still haven’t seen the top of this peak yet.”

Anyone can catch R.S.V., but it’s especially dangerous for infants, toddlers and older adults. In a typical year in the U.S., the virus kills about 14,000 adults 65 and older and up to 300 children under 5, as my colleague Emily Baumgaertner recently reported.

The virus clogs airways in the lungs, and the airways of young children are more easily blocked because they’re so small. In California, where rates of R.S.V. and hospitalizations are higher than they’ve been in years, at least two children have died from the virus since October, according to state data.

Unfortunately, this surge in California coincides with an uptick in coronavirus cases, as well as a large spike in flu cases. Only three states in the U.S. currently have more flu activity than California, according to data from the C.D.C.

On Nov. 14, California health officials reported the death of a child under 5 who was infected with both the flu and R.S.V. “This tragic event serves as a stark reminder that respiratory viruses can be deadly, especially in very young children and infants,” Dr. Tomás Aragón, the California Department of Public Health director, said in a statement.

Doctors suspect that children who ordinarily would have been exposed to R.S.V. over the last couple of years were not because of social distancing measures. “They’re all getting exposed for the very first time now, so we’re just seeing these frighteningly high levels of cases,” Hendriksz told me.

Hendriksz and other public health experts are encouraging parents to do whatever they can to protect their children’s health in other ways (like getting flu shots and Covid boosters) since there is no widely available vaccine for R.S.V.

In California, Orange County officials recently declared a health emergency because of record numbers of pediatric hospitalizations and emergency room visits, driven in part by growing numbers of R.S.V. cases. Officials in San Diego, Santa Clara, Los Angeles and several other counties have sounded similar alarms.

“Every children’s hospital that I’m aware of is absolutely swamped,” Dr. Coleen Cunningham, the pediatrician in chief at Children’s Hospital of Orange County, told Emily. The R.S.V. surge has been so severe for pediatricians, another doctor said, that “this is our March 2020.”

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What we’re eating

Creamy white bean and seaweed stew with Parmesan.

Where we’re traveling

Today’s tip comes from Ted Bosley, who recommends “the Eastern Sierra, from Lone Pine to Mammoth Lakes, especially about this time of year when tourism has thinned and the fall colors are brilliant.” Ted writes:

“Near Lone Pine is beautiful Whitney Portal at the foot of the highest peak in the lower 48 states; near Independence is the outstanding interpretation center at the Manzanar War Relocation site; the Ancient Bristlecone Pine Forest east of Big Pine and the Palisade glaciers west of town (see them while you can); relatively easy access to the High Sierra country from Bishop; and the high caldera surrounding Mammoth Mountain.”

Tell us about your favorite places to visit in California. Email your suggestions to CAtoday@nytimes.com. We’ll be sharing more in upcoming editions of the newsletter.

Tell us

Fall colors have made quite a showing in California this year, with gold and red leaves popping up in all parts of the state.

Send us your best fall foliage photos at CAToday@nytimes.com and we may share them in an upcoming newsletter. Please include your name and the city where you live.

And before you go, some good news

In case you missed it, three Californians squared off in the finals of the “Jeopardy!” tournament of champions last week.

Amy Schneider, a writer from Oakland, beat Andrew He, a software developer from San Francisco, and Sam Buttrey, an associate professor at the Naval Postgraduate School in Monterey.

“Any of the three of us really could have won if a very small number of things had gone differently,” Schneider told The Associated Press after her victory. Schneider’s 40-game winning streak remains the second longest in the game show’s history.