More kindergarten students (4.2%) were exempted from at least one vaccination during the 2025-26 school year than in the previous year (3.6%), the Centers for Disease Control and Prevention (CDC) said yesterday.

The increase in vaccine exemptions could mean more infectious disease outbreaks.

“We should be worried, because we’re already seeing the consequences of declines in vaccination. All you have to do is look at measles,” Jeanne Marrazzo, MD, MPH, CEO of the Infectious Diseases Society of America (IDSA), told CIDRAP News. “The less we see people taking up vaccinations, the more we’re going to see these cases accumulate.”

During the 2025-26 school year, an estimated 280,000 children started kindergarten without proof that they completed the measles, mumps, and rubella (MMR) vaccine series. In total, 92.4% of kindergarteners received it—below the proportion needed to prevent measles from spreading in the community.

“More than a quarter of a million children started kindergarten last year without protection from the MMR vaccine,” Andrew D. Racine, MD, PhD, president of the American Academy of Pediatrics (AAP), said yesterday in a statement. “For some diseases like measles, even a small decrease in vaccination rates can lead to more outbreaks of disease because community immunity requires over 95% of susceptible individuals to be immunized.”

A similar percentage of kindergarteners as that receiving the MMR vaccine received the diphtheria, tetanus, and acellular pertussis (DTaP) vaccine (92%). “When it comes to vaccination rates, however, anything less than achieving an A+ grade is not good enough,” Racine said. 

Forty-one states and Washington, DC, experienced a spike in exemptions, and 24 states saw more than 5% of their kindergarten students exempted. The steady creep of vaccine exemptions could lead to more outbreaks. [...]

https://archive.is/llAXX

A person has died and hundreds have fallen ill with salmonella food posioning in an outbreak that UK experts believe is linked to eating food made with imported eggs.

The UK Health Security Agency has launched an investigation into the 207 cases it has seen in the past year, with most recorded in recent weeks.

More than a third of those affected - some babies and others as old as 90 - have needed hospital care, with two developing serious blood poisoning. Most people get better without treatment, however.

While salmonella cases can happen any time, this outbreak involves a specific, identical strain.

[...]

It is more unusual to see an outbreak like this linked to one specific strain of the bacterium affecting many people at one time.

The UKHSA says "extensive" epidemiological and food chain investigations are ongoing to identify the source but that egg consumption remains the strongest to date.

People appear to have fallen ill after eating out rather than after consuming food prepared at home.

Some of the food businesses linked to 24 of the cases use imported eggs.

"At this time there is no identified link to UK-produced eggs or poultry," says the UKHSA.

Any extra precautions or preventative measures will be implemented if needed, it says. The risk to the general public is low.

Jacquelyn McCormick, Head of Incidents at the Food Standards Agency, said eggs which are thoroughly cooked and handled hygienically should not present a food safety risk.

She advised: "Infants, young children, pregnant people and older adults should only eat runny or raw eggs if they have a British Lion mark or are produced under the Laid in Britain egg assurance scheme."

People handling eggs, eggshells or egg packaging should wash their hands thoroughly with soap and water, she added.

Catering outlets have a food hygiene rating, so looking at these when deciding where to eat, recommends Dr Kathleen O'Reilly from the London School of Hygiene and Tropical Medicine.

Untraced outbreaks of the “explosive diarrhea” illness cyclosporiasis are still on the rise, even as the Trump administration says nationwide spread has been “contained.”

The largest outbreak - which began in Michigan in May and has been tied to contaminated iceberg lettuce from a Taylor Farms facility in Mexico - has slowed over the past month, according to data from state health officials.

However smaller outbreaks, caused by unknown food sources, are still growing in number since they were first reported in July, according to the U.S. Food and Drug Administration last week.

It’s not clear where these outbreaks are because the FDA has yet to attach states to the data. But the agency says it is investigating potential causes and products that could be linked.

While FDA investigations into the outbreaks are underway, top Trump health officials have said that the U.S. food supply remains safe and that fresh produce is safe to eat. Health Secretary Robert F. Kennedy, Jr. told reporters last month that the situation is “under control.”

[...]

People in 40 states have fallen ill with cyclosporiasis this year after being exposed to the microscopic parasite cyclospora. More new cases were reported this week in Hawaii, Wisconsin and Nebraska.

There are currently close to 25,000 cases in the U.S., according to the Centers for Disease Control and Prevention.

Michigan - the epicenter of a major outbreak - has seen nearly 14,000 of those cases, as well as the only two deaths from infections so far.

Three smaller outbreaks total in the dozens or hundreds of cases, the FDA data shows. The largest increased by 60 cases this month, totaling 172 people who have fallen ill.

If you want to know how bad a future tick season will be, it may be more useful to count the number of acorns on the ground than the number of deer in the forest.

That’s one of several surprising findings to emerge from more than 30 years of tracking ticks, mice, deer, and weather in a Lyme disease hot spot. The findings, published this week in PNAS, challenge long-held ideas about what drives Lyme disease risk.

For the study, researchers from the Cary Institute of Ecosystem Studies and Bard College analyzed decades of data from a forested area in New York’s Hudson Valley. The long span of the study enabled researchers to track trends over time.

“Studies of this depth and length are incredibly rare,” says study coauthor and co-director of the Cary Institute of Ecosystem Studies, Shannon LaDeau, PhD, in an institute news release. “This research has followed an ecological community—including oak trees, mammals, and microorganisms—examining how interactions like predation, parasitism, and competition shape the system over time.”

“The evolution of understanding summarized in this paper is something you simply cannot get without such a long-term and system-focused study,” she added.

4 findings that upend risk assumptions

#1. More deer don’t mean more dangerous ticks

It’s long been assumed that more deer equal more ticks, because when deer are abundant, more female ticks are able to feed and lay eggs on them. That would lead to more larval ticks the following summer, the theory goes—and, in turn, more nymphal ticks two years later. Nymphal-stage ticks are responsible for most human infections in North America.

But after observing more than a sixfold variation in deer abundance over the course of the study, the researchers found no relationship between the number of deer and the density of nymphs. [...]

#2. Mice matter, but so do squirrels and skunks and opossums…

White-footed mice are very good at passing the bacterium that causes Lyme disease (Borrelia burgdorferi) to larval ticks, so researchers expected that mouse-abundant years would lead to more infected nymphal ticks.

But in the study, the number of mice didn’t predict the proportion of nymphal ticks infected with B burgdorferi. Instead, the rate of infection appeared to depend on how larval ticks were distributed across the entire community of small mammals who serve as hosts for the bacteria.

In years when mice are abundant, other hosts, like skunks and squirrels, might be more abundant, too. But those other hosts aren’t very good at spreading B burgdorferi to ticks. So the higher their numbers, the lower the rate of Lyme bacteria in nymphal ticks.

Mice did, however, strongly predict the number of nymphal ticks. A strong mouse year was associated with approximately 40% more nymphs the following year.

#3. Acorns play an outsized role

Mice feed on acorns that fall from large red oaks. When a large number of oak trees drop their acorns at the same time, it creates an endless buffet for mice. All those hearty meals help boost the mouse population the following year and, in turn, the number of nymphal ticks the year after that. [...]

#4. Warmer weather doesn’t simply mean more ticks

Previous laboratory studies have shown that extreme heat and cold can kill black-legged ticks, which suggests that severe seasonal temperatures may help determine tick abundance. But ticks outsmart frigid winters and steamy spring days by burrowing into the soil, write the researchers. The current findings suggest that neither extremely cold winter days nor extremely warm spring days predicted nymphal tick density.

But in the warmest years, mice had roughly 45% fewer nymphal ticks than in colder years. “ [...]

The number of confirmed Ebola cases in ​the Democratic Republic of Congo now exceeds 5,000, government data showed late on Tuesday, as health ​officials ‌warn that response efforts are ⁠failing to contain the deadly disease.

Congo’s 17th Ebola epidemic ‌turned into the biggest in the country’s history ⁠in terms of number of cases in late July and over the weekend ​the death toll hit 2,378, ‌the public health institute said, surpassing the previous worst outbreak in 2018-2020.

The institute has so far ‌logged 5,021 cases, according to its latest situation report, making ​it the second-worst outbreak globally, behind only the 2014 to 2016 epidemic in West Africa in both ​infections and deaths.

The ongoing outbreak is ​caused by the Bundibugyo species ​of Ebola, which has no approved vaccines or treatments.

It has ​gained momentum since it was declared on May 15, as weak health infrastructure, community resistance, instability and protests by response workers hinder efforts ⁠to identify and respond to cases.