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"Pfizer has begun testing its COVID-19 vaccine in children under 12,” writes Apoorva Mandavilli at The New York Times (Pfizer’s vaccine is already authorized in the U.S. for children ages 16-18). And Moderna also is starting its COVID-19 vaccine studies in children under 12, the story states. “Both companies have been testing their vaccines in children 12 and older, and expect those results in the next few weeks,” Mandavilli reports. With children under 18 making up nearly a quarter of the U.S. population, vaccinating them may prove crucial to generating enough immunity to the entire nation’s population to prevent the spread of SARS-CoV-2 (aka herd immunity), according to a U.S. National Institutes of Health infectious diseases physician quoted in the 3/25/21 story.

At STAT, Matthew Herper’s coverage of the Pfizer studies of its COVID-19 vaccine in children as young as 6 months old suggests a scenario in which children ages 12 to 15 could be vaccinated against COVID-19 by this fall, when school resumes after summer vacation in the U.S. It will depend on how study data turn out as well as if and when the U.S. Food and Drug Administration authorizes a COVID-19 vaccine for emergency use in this age group. For younger children, any authorization probably would not come until early next year, the story states. In the Pfizer tests with children ages 6 months to 12 years old, the researchers might focus on antibody levels as an indicator of protection rather than on disease symptoms, Herper reports (3/25/21).

A study of 100 patients with “long COVID” in 21 U.S. states has revealed that 85 percent of these people experienced four or more neurological issues months after their initial infections, reports Pam Belluck at The New York Times (3/23/21). Reported symptoms include headaches (68 percent), tingling (60 percent), muscle pain (55 percent), troubles with the sense of smell (55 percent), brain fog (81 percent), dizziness, blurred vision, and ringing ears, according to the story and the study, published 3/23/21 in The Annals of Clinical and Translational Neurology. None of the study participants was ever sick enough from COVID-19 to be hospitalized, the story states (this is typical of most people infected with SARS-CoV-2, the study states). The findings underscore “the emerging understanding that for many people, long Covid can be worse than their initial bouts with the infection,” writes Belluck. In another study posted online this month but not yet evaluated by outside experts, a third of people with long Covid symptoms felt fine in the first 10 days after testing positive for SARS-CoV-2, the story states. A physician at the University of Texas Southwestern Medical Center says the symptoms could be caused by an inflammatory reaction to the virus that can affect the brain and the body.

It is possible for a COVID-19 vaccinated person to be infected with SARS-CoV-2 even after the two or so weeks it takes for strong protection to kick in, Katherine J. Wu writes at the Atlantic (3/19/21), but these cases are a “vanishingly small percentage” of all people who have been vaccinated. As she explains, “the goal of vaccination isn’t eradication, but a détente in which humans and viruses coexist, with the risk of disease at a tolerable low.” Each individual’s immune response to vaccination can differ somewhat in its strength. Think of your COVID-19 vaccination as a “layer of protection, like an umbrella, that might guard better in some situations than others,” Wu writes, drawing on the insights of a virologist at the Icahn School of Medicine at Mount Sinai, in New York. In many situations, “vaccines are still best paired with safeguards such as masks and distancing — just as rain boots and jackets would help buffer someone in a storm,” the story states.

In the first two months of COVID-19 vaccine roll-outs, SARS-CoV-2 infections fell rapidly among U.S. nursing home workers and nursing home residents, as well as among workers at some hospitals in England and Israel, according to data and research covered by Melissa Bailey and Shoshana Dubnow at Kaiser Health News (3/15/21). That said, COVID-19 vaccines are not mandatory in most U.S. nursing homes, Bailey and Dubnow report. And some nursing home workers don’t yet trust the vaccines, the story suggests. A combination of vaccines and “effective infection prevention and control programs/practices” have led to the drop in infections at such U.S. facilities, according to a U.S. Centers for Disease Control spokesperson quoted in the piece. A Johns Hopkins University infectious diseases specialist who advises nursing homes on COVID-19 responses emphasizes the role of hard-won immunity among SARS-CoV-2-infection survivors in long-term care facilities, as well as the role of vaccines. “Having even one or two vaccinated people in a building can slow transmission,” the specialist is described as stating.

On 3/10/21, the U.S. Centers for Medicare & Medicaid Services issued guidelines for nursing-home visitors allowing indoor visits regardless of vaccination status, with some exceptions.

Some useful double-masking tips can be found in this 3/17/21 guide by Tara Parker-Pope and Dani Blum at The New York Times, specifically: 1) Wear a cloth mask over a surgical mask rather than wearing two surgical masks to minimize side-gaps; and 2) there’s no need to double-mask if you’re wearing an N95 or KN95.

James Hamblin’s latest piece for The Atlantic (3/11/21) focuses on the uncertainties that remain regarding the future of the COVID-19 pandemic. He writes: “Today, the experts I trust most are those who seem to have grown less certain over the course of the pandemic, and have learned the humility it should force upon us all.” Marc Lipsitch, a Harvard School of Public Health epidemiologist who accurately forecast last year that SARS-CoV-2 would infect 40 to 70 percent of the U.S. (we’re currently around 40 percent the story states), said last July that he is “out of the business” of prediction, writes Hamblin, an MD and lecturers at the Yale School of Public Health. The pandemic will end with a whimper, not a roar, the piece suggests.

You might enjoy this 3/22/21 “Late Night with Seth Myers” sketch.