Getty ImagesA vaccine is to be trialled on thousands of people to find out if it could protect against norovirus – a stomach bug that causes vomiting and diarrhoea.

The C.D.C. said that nearly 50 people had become ill and one person had died from the deadly bacteria, which the agency tied to an ingredient in one of the fast food chain’s burger items.One person has died and 49 people have become ill from an E. coli outbreak linked to McDonald’s Quarter Pounder hamburgers, the Centers for Disease Control and Prevention said on Tuesday.McDonald’s has now stopped selling Quarter Pounders from locations in several states, mostly in the Mountain West, the C.D.C. said, and has also discontinued the use of slivered onions in all sandwiches in those states as health investigators try to determine which ingredient may be contaminated with the deadly bacteria.The public health agency called the situation “a fast-moving outbreak investigation” in its news release.The same strain of bacteria has sickened 49 dozens of people in 10 states, although the C.D.C. said most people were from Colorado and Nebraska. One Colorado resident has died. Ten people were hospitalized, including a child who the health agency said has a complicating illness.All of those interviewed said they had eaten at McDonald’s recently, and most said they had consumed Quarter Pounders. The fast-food chain told investigators it mainly uses fresh onion slivers on that item.Food and health investigators are also trying to determine whether any contaminated beef has been sold to other retailers or grocery stores.This is a developing story.

Patient advocates hope Dr. Michelle Tarver will lead the agency to focus more on safety and less on rapid approvals.The Food and Drug Administration on Tuesday announced that Dr. Michelle Tarver, an agency veteran, will be the new director of the medical device division.Dr. Tarver will face a slate of pressing tasks, that include addressing calls to strengthen standards to protect the public from issues like racial bias in artificial intelligence software and hastily authorized and faulty cardiac devices, like external defibrillators.She will also confront the challenge of restoring credibility to a division clouded by ethical lapses of Dr. Jeffrey Shuren, her predecessor, and of navigating her way in an agency with close ties to the industry.In addition, Dr. Tarver is assuming the position at a time of stunning technological advancement, overseeing research and potential approvals of devices meant to tap into brain signals to restore speech and movement.The division reviews thousands of medical products that are central to medical diagnosis and surgery, like DNA tests and surgical staplers. Other devices are implanted in the body for decades, including pacemakers and hip prostheses. The division has a budget of about $790 million and a staff of about 2,500.A 15-year veteran of the agency, Dr. Tarver is viewed by those inside the F.D.A. as a candidate who would sharpen the division’s focus on safety and quality. She is an ophthalmologist who continues to treat patients on the weekends, and she is also trained as an epidemiologist and has developed ways to measure patient preference in medical care.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

In a first, the guidelines link poor pregnancy outcomes to stroke and call on doctors to exercise greater vigilance.New guidelines for preventing strokes spell out for the first time the risks faced by women, noting that pre-term births and conditions like endometriosis and early menopause can raise the risk.“Prior guidelines tended to be sex-agnostic,” said Dr. Brian Snelling, director of the stroke program at Baptist Health South Florida’s Marcus Neuroscience Institute, who was not involved in writing the guidelines.“Now we have more data about sex-specific subgroups, so you’re able to more appropriately screen those patients.”The focus of the recommendations by the American Stroke Association, published on Monday in the journal Stroke, is primary prevention — the effort to prevent strokes in individuals who have never had one. It represents the first such update in a decade, and it’s the playbook by which millions of Americans will be cared for.A stroke is a sudden blockage of blood flow to the brain, or sudden bleeding in the brain. It is a leading cause of the death in the United States, and the incidence has been rising even among adults 49 and younger, stoked by increases in obesity, high cholesterol, diabetes and — perhaps most significantly — high blood pressure.Nearly 800,000 strokes occur each year, leading to severe disability and more than 160,000 deaths. Some 57 percent occur in women. At least 60 percent are preventable.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

The Federal Aviation Administration did away with a rule that had required an off switch for the sign even though smoking on U.S. flights ended years ago.The days of airplane cabins hazy with cigarette smoke are long gone, but a reminder of that era is still visible inside commercial jets.Smoking has been banned on commercial flights in the United States for decades, but the Federal Aviation Administration is only just updating an outdated rule to reflect that reality. Starting on Tuesday, the illuminated overhead “No Smoking” sign no longer requires an off switch.That obsolete requirement had become “time-consuming and burdensome” for airlines and airplane manufacturers to comply with, the F.A.A. said in a rule enacting the change. In February, for example, United Airlines was briefly unable to use a handful of new Airbus planes because the “No Smoking” signs on board couldn’t be shut off, causing the airline to delay a few flights. The issue was resolved after the F.A.A. granted United an exemption.Dozens of such exemptions have allowed that requirement to live on while the agency focused on more pressing matters. But the long life of the mandate also reflects how entangled smoking once was with commercial flights, which began in the 1910s.“The rise of aviation literally parallels the rise of the cigarette,” said Alan Blum, the director of the University of Alabama’s Center for the Study of Tobacco and Society.Pipes, cigars and chewing tobacco were once more popular than cigarettes, but that began to change in the early 20th century, according to Dr. Blum. During World War I, cigarettes were added to rations for American soldiers fighting abroad.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

News presenter Andrea Byrne has said she feared her husband would be “better off” without her during the couple’s seven-year experience of infertility.

Artificial intelligence (AI) has the potential to reduce the number of fractures and broken bones missed when doctors analyse X-rays, according to the National Institute for Health and Care Excellence (NICE).

The Ames Test offered a fast and inexpensive way to identify carcinogens, leading to the banning of chemicals linked to cancer and birth defects.Bruce Nathan Ames, a biochemist who discovered a revolutionary method of detecting potential carcinogens, paving the way for the banning of many commonly used chemicals, died on Oct. 5 in Berkeley, Calif. He was 95.His wife, Giovanna Ferro-Luzzi Ames, said his death, in a hospital, was from complications after a fall.The so-called Ames Test, developed in the 1970s, is still used by drug manufacturers and pesticide companies to check the safety of their products. It involves exposing chemicals to a mutant strain of salmonella bacteria that Dr. Ames created; how the bacteria responds to a chemical makes it possible to determine whether that chemical caused DNA damage and therefore might lead to cancer in humans.In an America increasingly concerned about the effects of pollution and industrial chemicals, the test offered a quick, inexpensive alternative to animal testing, which was so prohibitively expensive that regulators were able to test only a fraction of chemicals on the market.“It changed the regulatory sphere,” said Angela Creager, a science historian at Princeton University who is writing a book about the Ames Test. “It showed that it was actually possible to get toxicity information on every chemical if we wanted to.”After capturing the attention of the national press, Dr. Ames remained in the spotlight as he used the Ames Test to expose the toxicity of a number of commonplace chemicals.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

Some members of the public have not taken Health Secretary Wes Streeting’s call for new ideas to improve the health service as seriously as he might have hoped.

After 44 days, Kendric Cromer, 12, left the hospital. While his family feels fortunate that he was the first to receive a treatment, their difficult experiences hint at what others will be up against.Kendric Cromer, 12, left Children’s National Hospital in a wheelchair on Wednesday, wearing a T-shirt and cap printed with designs from the anime series “Naruto” and a black face mask. Staff lined the hallway, cheering and waving noisemakers. He had just become the first patient to receive a gene therapy for sickle cell since it was approved — a therapy that is expected to free him from the ravages of the disease.After 44 days in the hospital, he was a bit dazed.“I thought I would have sickle cell for the rest of my life,” he said. The disease had deprived him of his childhood, making everyday activities, like playing basketball or riding a bike, impossible because they could bring on searing pain, often resulting in hospitalizations.But despite the celebratory atmosphere, Kendric and his parents are still shuddering over what they endured during his hospital stay.Nothing, absolutely nothing — not all the discussions with doctors, not all of their reading and highlighting of texts, not the 13-page consent form that included organ damage and even death as possible outcomes — prepared them for what he would go through.About 100,000 people in the United States have sickle cell disease. For the 20,000 or so with the most severe disease, gene therapy may be their only hope of living a normal life. The disease is caused by a mutation in hemoglobin genes that leads to crescent-shaped red blood cells, which tend to get stuck in blood vessels, causing episodes of excruciating pain. The blockages can damage organs, cause strokes and shorten lives.Until recently, most saw no way out.Then, last December, the Food and Drug Administration approved a $3.1 million sickle cell gene therapy by Bluebird Bio of Somerville, Mass., and a $2.2 million treatment by Vertex Pharmaceuticals of Boston. That potentially gives patients like Kendric, if their insurance will pay for the therapy, a path to a life that is not shadowed by the ravages of the disease.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.