Times Reporters Answer Your Vaccine Questions

The vaccine situation in the United States has become chaotic, and it can be hard to keep up. An advisory committee voted last week to limit access to Covid vaccines and combination shots for measles, mumps, rubella and chickenpox. President Trump and Health Secretary Robert F. Kennedy Jr. say that vaccines may be linked to autism, a claim that has been discredited by decades of scientific studies.

We know you have questions about vaccines. The Times asked what readers wanted to know — and received hundreds of queries about efficacy, safety, cost and access. Today’s newsletter brings you answers, courtesy of health and science reporters: Maggie Astor, Dani Blum, Teddy Rosenbluth, Apoorva Mandavilli, Reed Abelson and Emily Baumgaertner Nunn. See more answers about flu shots and the childhood vaccine schedule.

Are Covid shots available?

Largely, yes. On paper, anyone 6 months and older should be able to get the updated shots (which target more recent variants of the coronavirus).

In practice, though, some people may face challenges. Pharmacies in some states have been requiring prescriptions, even for those in high-risk groups; while that is likely to change if the C.D.C. adopts recent recommendations, a new provision that urges people to consult a medical professional before getting vaccinated may create barriers. Many pharmacies and doctors aren’t stocking pediatric doses. And although the C.D.C. recognizes pregnancy as a high-risk condition, it has stopped recommending vaccination during pregnancy.

What happened to the M.M.R.V. vaccine?

Parents have had two options for protecting their children against measles, mumps, rubella and chickenpox. Option No. 1: Children get two shots — one for chickenpox, and another that covers the rest.

Option No. 2: Children get one combined shot, called the M.M.R.V. That one slightly increases the risk of fever-induced seizures in young children, which can alarm parents but do not cause lasting harm. Parents may choose this option to reduce the number of injections or clinic visits.

An advisory panel now says that the C.D.C. should eliminate the choice and recommend only the separate shots.

Will insurance pay?

Probably. Under the Affordable Care Act, almost all insurers must fully cover vaccines recommended by the C.D.C. They don’t have to cover other shots, but they can choose to — and many say they plan to disregard recent changes. For instance, a trade association for health insurers said this month that through at least the end of 2026, its members would cover all vaccines that the C.D.C. recommended as of Sept. 1.

If you don’t have insurance, out-of-pocket costs vary. The C.D.C. maintains a list of private-sector prices. But this list reflects only how much providers pay. They are likely to charge you more — potentially more than $200 for Covid shots at a pharmacy, and around $290 for M.M.R.V.

How do we know they’re safe?

New shots are rigorously evaluated to ensure that their benefits outweigh their risks.

Testing begins in lab animals, like mice or primates. If the vaccine appears to be safe and promising, it advances to its first clinical trial. This trial often includes fewer than 100 people. After that, researchers monitor side effects in a larger trial, which includes more participants of different ages and backgrounds. Finally, the vaccine is tested in thousands — sometimes as many as tens of thousands — of participants, which lets the researchers detect rare side effects.

The process can take up to a decade, after which the F.D.A. reviews the data and decides whether to approve the shot. And officials continue to collect data about vaccine side effects even after its approval. Health agencies may update recommendations or add warning labels if they find a link between a serious side effect and a vaccine.

Can vaccines be dangerous?

Significant side effects are rare. Shots may produce fatigue, fever and pain at the injection site. But health officials withdraw immunizations that cause bigger problems. For example, in 1999, the C.D.C. withdrew its recommendation for a rotavirus vaccine that was associated with intestinal blockages in children, and the manufacturer voluntarily ceased production.

A fraction of a percent of young people — especially young men between 12 and 24 — who receive their first two doses of Moderna’s and Pfizer’s Covid shots may experience myocarditis, or heart inflammation. In all age groups, myocarditis is more common after contracting Covid than after getting a Covid vaccine. Myocarditis is treatable, and most people who experience it recover fully.

Flu shots are also very safe. Guillain-Barré syndrome — in which the immune system attacks nerves — occurs in one or two recipients in a million, and flu infections are much more likely than vaccines to cause it.

THE LATEST NEWS

ICE Office Shooting

• A gunman perched on a rooftop in Dallas opened fire on an Immigration and Customs Enforcement detention center. He killed one detainee and critically injured two others. No officers were injured.

• Americans were searching online for information about the gunman, who was 29 and killed himself. Officials said he left behind ammunition with an anti-ICE message, though his extensive online footprint did not include much about politics.

• This was the third shooting at a federal immigration facility in Texas recently. The other two were in July. In one, a police officer was shot and 10 people were charged. In the other, three people were injured, two of them officers, and the gunman was killed.

Climate Change

• China promised to reduce greenhouse gas emissions by at least 7 percent over the next decade.

• At a Times conference, speakers discussed Trump’s climate policy. Gavin Newsom, California’s governor, called the president’s derisive comments about climate change at the U.N. an “abomination.” The U.S. energy secretary, Chris Wright, urged other countries to leave the Paris Agreement.

United Nations

• Ahmed al-Shara became the first Syrian leader to address the U.N. General Assembly in 58 years. He told The Times that his jihadist past had prepared him to do what no one else could: topple the Assad regime.

• Volodymyr Zelensky told fellow leaders they were living through “the most destructive arms race in human history,” citing the cheap, deadly drones built to fight in Ukraine.

War in Gaza

• Our colleague Ismaeel Naar flew with injured Gazans being taken to the U.A.E. “Starvation is a medical condition we thought the world had stopped needing to treat,” an Emirati health official said.

• An Israeli airstrike killed nearly two dozen Palestinians in Gaza City, the rescue service there said. Israel said it had hit two Hamas figures.

More International News

SPORTS

M.L.B.: The top two American League M.V.P. candidates had huge nights. The Yankees’ Aaron Judge became the fourth player to hit 50 home runs in four seasons. Seattle’s Cal Raleigh became the seventh player ever to hit 60 in a season.

N.F.L.: Tom Brady defended himself over concerns about a conflict of interest between his roles as a Fox analyst and a Las Vegas Raiders minority owner.

A LONG LIFE

“Please study me.” That was the last request of Maria Branyas Morera, the world’s oldest living woman, before she died last year. She was 117.

So Dr. Manel Esteller, the head geneticist at the University of Barcelona’s medical school, and his team examined her cells. They found that her genes contained variants that seem to protect against factors like dementia, heart disease and cancer — a genetic lottery win. She also had an abundance of healthy bacteria, Dr. Esteller noted, possibly thanks to the three yogurts she ate every day.

Scientists caution that good genes and yogurt won’t keep you alive on their own. Dr. Esteller’s study found that Branyas’s longevity came in large part from her lifestyle: She followed a Mediterranean diet, didn’t smoke or drink and had a close circle of family and friends.

“She lived a healthy life,” Dr. Esteller said.

More on culture

• London Fashion Week showed that tulle, suits and pink are in style.

• A statue of Trump and Jeffrey Epstein holding hands was removed from the National Mall.

• A museum curator fled Thailand after China objected to parts of a show criticizing authoritarian regimes.

• “You can’t believe they gave me my job back?” Kimmel said in his monologue, addressing Trump. “I can’t believe we gave you your job back.” Read more from the late night shows.

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