Coronavirus Briefing: What Happened Today

• The W.H.O. warned that a variant in India could be highly contagious.

• A C.D.C. advisory panel recommended Pfizer’s vaccine be made available to 12- to 15-year-olds.

• The leaders of Emergent, whose factory spoiled vaccine doses, will testify before a U.S. House panel next week.

• Get the latest updates here, as well as maps and a vaccine tracker.

A closer look at unvaccinated Americans

The recent drop in vaccinations in the U.S. has been attributed to “vaccine hesitancy” — a mishmash of misinformation and mistrust. But there’s another group of unvaccinated Americans who are amenable to getting a dose but haven’t yet, and their reasons are complex.

They number around 30 million, according to census estimates. They’re not opposed to the vaccine, or even skeptical. In interviews, their stated reasons for not getting vaccines are disparate — not wanting to miss work because of side effects, barriers to access and social isolation.

Acy Grayson III, who runs a home improvement outift in the suburbs of Cleveland, told The Times that he found it hard to commit to a time and place because of his job.

“I know you’re trying to find out the reason people aren’t doing it,” Mr. Grayson said. “I’m going to tell you. People are trying to take care of their household. You don’t have much time in the day.”

For the most part, these folks are among America’s working class and are busy balancing jobs and family obligations that make it difficult for them to find time to travel to get a dose, let alone two. About half live in households with incomes of less than $50,000 a year, according to an analysis of the census data by Justin Feldman, a social epidemiologist at Harvard.

Eighty-one percent do not have a college degree. Some have health issues or disabilities or face language barriers that can make getting inoculated against Covid seem daunting. Many live in counties that rank high in a C.D.C. index of social vulnerability — high poverty rates, crowded housing and poor transportation access.

Vaccine historians say there is no playbook for inoculating so many adults with a day job. And as public health departments close down mass vaccination clinics because of low turnout, they are seeking new ways to reach people, including pop-up clinics in grocery store parking lots or at churches.

Reaching these populations is critical for everyone. If the country doesn’t reach high levels of vaccination, experts say, the virus is likely to continue circulating in pockets, causing unnecessary hospitalizations and deaths. A recent data analysis conducted by Lauren Ancel Meyers at the University of Texas at Austin suggests that vaccinating more residents early on in Austin’s hardest-hit Covid areas would have prevented hospitalizations and deaths across the whole city.

“Putting more resources into protecting high-risk populations can be life saving and beneficial to us all,” Meyers said.

China faces questions over vaccine

China expected its Sinopharm vaccine to be the linchpin of its vaccine diplomacy program. The vaccine is easy to transport, making it a logical option across China and the developing world. In a bid to win good will, China donated 13.3 million Sinopharm doses to other countries.

But instead of praise, the company, which has made two varieties of coronavirus vaccine, is facing mounting questions about the inoculations. First, there was the lack of transparency with Sinopharm’s late-stage trial data. Now, Seychelles, the world’s most vaccinated nation, has had a surge in cases and had to reimpose a lockdown, despite much of its population being inoculated with Sinopharm.

Among those in Seychelles who have received two doses, 57 percent were given Sinopharm, while 43 percent were given AstraZeneca. Among new cases, 37 percent are people who are fully vaccinated, according to the health ministry, although it did not say how many had the Sinopharm shot.

Dr. Kim Mulholland, a pediatrician at the Murdoch Children’s Research Institute in Melbourne, Australia, said the initial reports from Seychelles correlated to a 50 percent efficacy rate for the vaccine, instead of the 78.1 percent rate that the company had touted. By contrast, a study has shown that the Pfizer vaccine used in Israel — the country with the second-highest vaccination coverage — is 94 percent effective.

The news is a huge setback not just for Seychelles, but also the 56 other countries counting on the Sinopharm shot. It may also deepen the vaccine access gap between rich and poor nations. If developing nations choose the Chinese vaccines, they could end up lagging behind countries that select more effective doses, which could allow the pandemic to continue in countries that have the fewest resources to fight it.

Vaccine rollout

• Many parents in the U.S. are hesitant about giving their children the Covid shot, even if they’re not anti-vaccine.

• Ontario will no longer administer AstraZeneca’s vaccine to new patients because of the risk of rare blood clots, CBC reports.

• Cuba deployed unproven homegrown vaccines, hoping to slow an exploding virus outbreak.

• Some states have already started vaccinating 12- to 15- year-olds against Covid, Kaiser Health News reports.

See how the vaccine rollout is going in your county and state.

What else we’re following

• To prevent the next pandemic, experts presenting to the W.H.O. recommended swift mask mandates, travel restrictions, an international treaty and the creation of new bureaucracies.

• Scientists told a House panel that coronavirus variants will pose a continuing threat to the U.S., with the potential to spread quickly and blunt the effectiveness of vaccines.

• Goa, a popular vacation destination in India, is facing a devastating surge of infections.

• South Carolina’s governor lifted the mask mandate for children in schools.

• More than 99 percent of patients hospitalized with Covid at the Cleveland Clinic between Jan. 1 and April 13 were not fully vaccinated, Axios reports.

• Here’s a look at how 723 epidemiologists in the U.S. are negotiating the current climate, as vaccination rates rise but Covid is still a threat.

• In Nepal, oxygen cylinders from Mount Everest could soon be used by Covid patients.

What you’re doing

I really wish there was a way to send a reply to some of the amazing people who have written into the newsletter. I am often moved to tears or just want to say: “Good for you!” Recently there was an entry about someone going to visit their dad after so long but thought he had gone too far downhill during the isolation and he would no longer remember them. “Go!” I want say. “You may be the very thing that brings him back around.” I am a single gay man turning 70 next week and have spent the last 16 months alone, broken and scared. The folks writing in have me feeling less alone, give me hope, and I thank you.

— Brian J. Moriarity, Chicago

Let us know how you’re dealing with the pandemic. Send us a response here, and we may feature it in an upcoming newsletter.

Correction: Yesterday’s newsletter misspelled the name of the ride-sharing company Lyft.

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