The outbreak may be the first ever documented in marine mammals.For the last three years, scientists in South Africa have been trying to unravel a grim marine mystery: What was happening to the Cape fur seals?The boisterous marine mammals, which are common along the nation’s shores, began washing up dead in enormous numbers. Pregnant females delivered dead premature pups. And some seals began displaying unusually aggressive behavior, attacking humans, dogs and each other.Some scientists suspected that a neurotoxin produced by algae might be to blame. In recent weeks, however, another specter has come into focus: rabies.So far, 17 seals have tested positive for the virus, said Tess Gridley, a founding director of Sea Search Research and Conservation, who has been investigating the seal deaths. The cases, which date back to at least August 2022 and span hundreds of miles of coastline, may be the first sustained rabies outbreak ever documented in marine mammals.“What I’m doing here is sitting here and putting together all the reports of aggressive interactions between seals and dogs and seals and people in the past few years,” Dr. Gridley said. “And it’s telling quite a scary story.”Rabies, which is nearly always fatal once symptoms occur, spreads through the saliva of infected animals. So far, no human cases have been reported, but, according to Dr. Gridley’s tally, at least 72 people in South Africa have been bitten or scratched by Cape fur seals since 2021; eight have been bitten by seals since confirmed to have rabies.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.

Wildfire smoke from the Western United States and Canada is blowing across the Northeast, lowering air quality and endangering vulnerable populations.Wildfire smoke from hundreds of fires burning in the West reached New England on Thursday afternoon. A long tendril of haze could lower air quality in cities along the coast, including in Delaware, New Jersey, Cape Cod, New Hampshire, New York City and even parts of Maine.Last summer, Canada’s record wildfires at times blanketed smoke across the United States as far south as Florida, and the current fires have raised fears that this year could see a similar intensity.Where are most of the fires?Wildfires are burning across Western Canada and the Western United States, where 89 active wildfires had burned more than 1.6 million acres as of Thursday morning, with the most extreme fires concentrated in Oregon and Washington.In Canada’s westernmost provinces of Alberta and British Columbia, more than 600 wildfires were actively burning and tens of thousands of people had been evacuated from their homes, including in Jasper, a popular tourist destination.Officials in both British Columbia, and Calgary, Alberta’s largest city, warned of deteriorating air quality levels this week. Some forecasts were so low that Mike Flannigan, a professor of wildland fire at Thompson Rivers University in British Columbia, called them “horrific.”“A warmer world means more fire,” Dr. Flannigan said. “These fires are consistent with what we expect with climate change.”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.

A large study showed that for most patients, having both breasts removed after cancer was detected in one made no difference.For the more than 310,000 women diagnosed with breast cancer every year, no matter how well the treatment goes, there is always a lingering fear. Could the disease come back, even years later? And what if it comes back in the other breast? Could they protect themselves today by having a double mastectomy?A study has concluded that there is no survival advantage to having the other breast removed. Women who had a lumpectomy or a mastectomy and kept their other breast did just as well as women who had a double mastectomy, Dr. Steven Narod of Women’s College Hospital in Toronto and his colleagues reported, using U.S. data from more than 661,000 women with breast cancer on one side.In the study, published in JAMA Oncology on Thursday, the researchers added that most women did very well — the chance of cancer in the other breast was about 7 percent over 20 years.But the study’s results may not apply to women who have a gene variant, BRCA1 or BRCA2, which greatly increases their cancer risk. For the 1 in 500 American women with this variant, cancer researchers agree that it’s worth considering a double mastectomy.The finding that a double mastectomy is not protective against death for many breast cancers seems counterintuitive, Dr. Narod admitted. An accompanying editorial, by Dr. Seema Ahsan Khan, a breast cancer surgeon at Northwestern University, and Masha Kocherginsky, a biostatistician also at Northwestern, called it a conundrum.Previous smaller studies have come to the same conclusion. But, Dr. Narod said, some doctors have questioned the methods in earlier research. 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.

Being vaccinated against shingles may also help delay getting a dementia diagnosis – a study in the journal

Getty ImagesThe NHS is appealing for people with O-type blood to urgently come forward and donate, after blood stocks dropped to “unprecedently low” levels in England.

BBCIt would take more than eight years for the NHS to see all adult patients waiting for ADHD assessments in many parts of the UK, a BBC investigation has found.

A new study paints a complex picture of the outbreak, suggesting that the virus could be spreading in multiple ways and that it is not always mild in cows.As the bird flu outbreak in dairy cows has ballooned, officials have provided repeated reassurances: The virus typically causes mild illness in cows, they have said, and because it spreads primarily through milk, it can be curbed by taking extra precautions when moving cows and equipment.A new study, published in Nature on Tuesday, presents a more complex picture.Some farms have reported a significant spike in cow deaths, according to the paper, which investigated outbreaks on nine farms in four states. The virus, known as H5N1, was also present in more than 20 percent of nasal swabs collected from cows. And it spread widely to other species, infecting cats, raccoons and wild birds, which may have transported the virus to new locations.“There’s probably multiple pathways of spread and dissemination of this virus,” said Diego Diel, a virologist at Cornell University and an author of the study. “I think it will be really difficult to control it at this point.”The outbreak, which officials first announced in March, has spread to at least 170 dairy farms in 13 states, according to the Department of Agriculture. It has also jumped into poultry farms and infected at least 10 farmworkers exposed to infected cows or poultry.The exact origins of the outbreak remain unknown, but scientists believe that the version of H5N1 that is now circulating in dairy herds probably jumped into cows just once, most likely in late 2023 in the Texas Panhandle.In the new study, the scientists focused on nine farms — five in Texas, two in New Mexico and one each in Kansas and Ohio — that reported outbreaks between Feb. 11 and March 19. When they analyzed samples of the virus taken from affected farms, they found that those samples were closely related to one collected from an infected wild skunk in New Mexico in February.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.

Science Photo LibraryA woman had to be tested for HIV after being given a vaginal examination with a swab already used on another patient, the health ombudsman has said.

Progress in the quest to help progeria patients suggests that gene editing techniques may help treat other ultrarare conditions.A cure for an ultrarare disease, progeria, could be on the horizon. The disease speeds up aging in children and dramatically shortens their lives. But, until recently, there was no path toward a highly effective treatment.Now, a small group of academics and government scientists, including Dr. Francis Collins, the former director of the National Institutes of Health, is working with no expectation of financial gain to halt progeria in its tracks with an innovative gene editing technique.If gene editing is effective in slowing or halting progeria, researchers say, the method may also help to treat other rare genetic diseases that have no treatments or cures and, like progeria, have aroused little interest from drug companies.After a quarter-century of research, the group is approaching manufacturers and planning to seek approval from regulators for a clinical trial on progeria gene editing.The project “has merit, but also risk,” said Dr. Kiran Musunuru, a gene editing researcher at the University of Pennsylvania, who also advises a gene editing company. He cautioned that although the editing worked well in mice, there is no guarantee that it will work in human patients.Dr. Collins first became interested in progeria while he was training in medical genetics at Yale University in 1982, almost three decades before he was appointed to lead the N.I.H. One day, he saw a new patient, Meg Casey. She was less than four feet tall, hairless under her wig and wrinkled like an older woman. She was only in her 20s.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.

Getty ImagesWeight-loss treatment Wegovy has been approved by the UK’s medicines regulator, for reducing the risk of serious heart problems in overweight and obese people.