Metformin given within a week of COVID-19 slashes risk of long COVID, death by 53%, paper notes

Popular diabetes drug offers new benefit

Meghan Holohan

Long COVID—or new-onset symptoms or worsening health conditions after SARS-CoV-2 infection—can lower quality of life. Finding a way to prevent it would be a welcome relief for those worried about the long-term effects of the viral infection. 

A study published last week in the Journal of Medical Virology finds that US COVID-19 patients prescribed metformin, a medication that treats prediabetes and type 2 diabetes, within six days of COVID-19 infection were less likely to develop long COVID or die. 

“Metformin prescription within the week following documented SARS-CoV-2 infection was associated with a 53% reduction in LC/D [long COVID or death] over 6 months in this primarily Omicron-infected sample,” wrote the authors, led by researchers from the University of Minnesota Medical School. 

Oh the horror!

Real men eat tofu

Animal vs. Plant Protein: New Study Reveals Unexpected Testosterone Differences

By University of Eastern Finland

An observational study of middle-aged men links animal protein to lower testosterone and plant protein to higher levels, but the differences are small, and their health effects remain unclear.

A protein-rich meal gives the body amino acids, the building blocks it needs to make and repair tissues, including muscle. Testosterone helps regulate muscle growth and also supports bones and sexual function. Food provides essential materials, while hormones help direct what the body does with them.

That connection makes diet a reasonable place to look when studying testosterone, yet relatively few studies have examined its relationship with protein intake.

Researchers at the University of Eastern Finland found that men who consumed more animal protein tended to have lower total testosterone levels in their blood. Those who consumed more plant protein tended to have higher levels. The findings do not mean that higher testosterone is necessarily healthier or that one protein source improves hormone function.

Dairy and meat show different hormone links

The research, published in the International Journal of Food Sciences and Nutrition, included 2,546 men aged 42 to 60 living in eastern Finland. 

Does Pete eat enough tofu?

It drew on the university’s ongoing Kuopio Ischaemic Heart Disease Risk Factor Study. Researchers assessed the men’s diets using four-day food records collected between 1984 and 1989 and measured total testosterone in blood samples. They also measured sex hormone-binding globulin, or SHBG, a protein that binds to sex hormones and influences total testosterone concentrations in the blood.

Looking at individual foods revealed a distinction that the broad category of animal protein could obscure. Higher dairy protein intake was associated with lower total testosterone and SHBG levels. Meat protein intake was associated with lower SHBG, but it had no association with total testosterone. Among plant foods, higher protein intake from vegetables and sources other than cereal products was associated with higher total testosterone.

To compare the differences, the researchers divided the men into four groups according to their protein intake. Those in the highest animal protein group had total testosterone concentrations averaging 1.2 nanomoles per liter (nmol/L) below those in the lowest group. For plant protein, the highest intake group averaged 1.1 nmol/L above the lowest group. SHBG showed similar opposing associations with animal and plant protein intake.

“Although the observed differences in testosterone concentrations were statistically significant, they were relatively small. Based on this study, it is not possible to infer whether these differences have implications for health,” says Doctoral Researcher Miika Wynne-Ellis from the University of Eastern Finland.

Scientists discover a surprising link between vitamin C and cancer survival

Could help in the treatment of cancer

Van Andel Research Institute

A surprising clinical trial suggests that taking vitamin C daily could improve survival in people with precancerous blood disorders and early-stage blood cancers. Patients receiving the supplement had fewer adverse events and showed a promising survival advantage, raising hopes that a common vitamin could help protect against leukemia-related complications.

Vitamin C plays an important role in keeping the immune system healthy, helping wounds heal, and protecting cells from damage. However, people with precancerous blood disorders and blood cancers often have persistently low vitamin C levels. Researchers have been investigating whether correcting this deficiency could improve their health and treatment outcomes.

New findings from the phase 2 EVITA clinical trial suggest that vitamin C supplementation may offer important benefits for people with precancerous blood conditions and early-stage blood cancers. The randomized, double-blind, placebo-controlled study was conducted by the Van Andel Institute-Stand Up To Cancer® Epigenetics Dream Team.

A simple blood test could detect cancer

Canadian advance toward earlier cancer detection

Alexandre Pellan Cheng, École de technologie supérieure (ÉTS)

American Association for Cancer Research

Cancer is now the leading cause of death in Canada. Two in five Canadians will develop cancer during their lifetime, and one in four will die from it. Every day, nearly 700 people across the country are diagnosed with cancer. According to the Canadian Cancer Society, the most commonly diagnosed cancers are lung, breast, prostate and colorectal cancer.

These figures mask a key reality: survival rates vary greatly depending on the type of cancer and, above all, how advanced it is at the time of diagnosis.

The statistical data clearly show that survival rates decrease when the cancer is detected early. These data highlight the urgent need to improve detection of the disease and, above all, to detect it earlier.

A blood test instead of a scalpel

This is the context where my research takes place. As a professor of systems engineering at ÉTS Montréal and principal investigator in the cancer research division at the CHUM Research Centre, I am working on liquid biopsy. This approach aims to detect cancer from a simple blood test by analyzing the DNA that tumor cells release into the bloodstream.

Unlike conventional biopsies, which require removing a tissue sample from the tumor, liquid biopsy relies on a simple, minimally invasive procedure: a blood test is all that’s needed.

The advantages of this approach include reduced pain, lower risks for the patient and less logistical burden associated with hospital procedures. The simplicity of the test also allows for more frequent testing. And finally, unlike many diagnostic procedures, taking a blood sample does not require specialized facilities. Blood can be taken in any health-care setting, whether it’s a local clinic or a community health center.

In medicine, the term “biomarkers” is often used to refer to measurable indicators that provide information about a person’s state of health. The PSA (prostate-specific antigen) test, which has been used for decades to monitor prostate cancer, is a well-known example. Elevated PSA levels in the blood may indicate the presence of cancer, its progression, or a recurrence after treatment.

However, the biomarker approach does have limits: PSA is not specific to cancer and test levels can rise for other reasons, which can complicate the interpretation of results.

Microplastics Are Chemically Active, and Could Cause Biological Harm

Ignore industry claims that plastic is inert

Columbia Climate School

Highlights

• Researchers found that microplastics and nanoplastics can react with surrounding water to generate highly reactive molecules, challenging the view that plastics are chemically inert.
• As plastics break into smaller particles, their surface area increases relative to their volume, creating more sites where these reactions can occur.
• The findings identify a potential mechanism for biological harm from microplastic exposure, including in the water-rich environments of blood and cells.
• Understanding this chemistry could help researchers redesign plastics to reduce their potential impacts on human health and the environment.

Plastics are supposed to be chemically inert. It’s the reason they’re used so frequently to package food, bottle water and create children’s toys. 

But something important happens when a large piece of plastic fragments into micro and nanoparticles: its surface area increases dramatically relative to its volume. Vastly more of the material is now exposed to its surroundings.

A new study by researchers from Columbia University and the University of California, Berkeley, found that this newly created surface is not necessarily safe and identified the chemical reasons why.

Trump Administration Delays Awards Slated To Improve Rural America’s Health

Charlestown, Narragansett Tribe and other South County communities among populations expected to benefit

By Sarah Jane Tribble, Arielle Zionts, and Bram Sable-Smith

EDITOR'S NOTE: According to Rhode Island's budget submission for this program, RI's share was expected to be $156,169,931. $96,405 was earmarked for the Narragansett Indian Tribe here in Charlestown. Source: RI Budget | DocumentCloud. - Will Collette

Federal leaders overseeing a $50 billion rural health fund missed a critical deadline to announce how much they’ll give states next year, alerting state leaders to the delay with a mass email.

A 12-sentence message from Alina Czekai, director of the federal Office of Rural Health Transformation, said officials “discovered an additional administrative process requirement.”

The Rural Health Transformation Program, which President Donald Trump touted as an “unprecedented” investment to “revitalize hospitals in our cherished rural communities,” calls for federal regulators to award states shares of $10 billion a year for five years.

In 2026, each state was awarded between $147 million and $281 million, with allocations determined by a federal scoring process to be revisited each year. State leaders had just over seven weeks last year to write applications as they competed against one another for first-year funds.

A national program of “this size, scope, and complexity” that has operated on a tight timeline is going to have “unforeseen issues in implementation,” said Alan Morgan, chief executive of the National Rural Health Association, which represents rural hospitals and clinics. “It’s just going to happen.”

Since the program launched last summer, state leaders have raised concerns about tight deadlines and burdensome reporting demands. First-year progress reports show state leaders have complied with federal demands to boost rural health technology infrastructure while also sending money to local communities.

Still, the speedy rollout did not “set anybody up for success to make meaningful progress,” said Lori Foley, who leads revenue and compliance advisory at PYA, a national consulting firm that has worked with regional and local health systems over the past year.

For state leaders, the Oct. 30 email has only added to the pressures of the previous months. One called the email funding alert “cryptic.” Another said there have been “plenty of surprises along the way.” One Midwestern state health association leader said her staff was “in the dark over here” about the funding. KFF Health News agreed not to name the state officials because they feared retribution.

New Pancreatic Cancer Vaccine Sparked Immune Responses in 99% of Patients

Hope in fight against one of the deadliest cancers

By Carly Cassella

Pancreatic cancer is incredibly difficult to shake.

Even after surgery or chemotherapy, the disease may never go away completely.

By some estimates, malignant tumors in the pancreas can recur in up to 80 percent of patients.

Those with certain gene mutations appear particularly at risk of the disease returning.

A new clinical trial, led by a researcher at the Mayo Clinic, has put a potential vaccine to the test.

In a randomized phase 2 trial, nearly every patient who received this vaccine developed an immune response against a mutated gene called KRAS.

Mutations in KRAS are found in about 90 percent of pancreatic ductal adenocarcinomas, which is the most common type of pancreatic cancer.

If a medicine can target cells that express these mutations, it could theoretically keep the cancer at bay.

This does not prove that this vaccine can stop pancreatic cancer from coming back, but these are hopeful signs, especially since other cancer vaccines have shown similar immune responses are linked to improved survival.

The findings are published in Nature Medicine.

Scientists Discover a Surprising Dental Benefit of Cranberry Juice

The catch: Applies to unsugared juice, not sweetened

By University of Illinois at Chicago

In a small human study, unsweetened pure cranberry juice was linked to slower plaque regrowth and lower acid production, hinting at a possible oral health benefit.

Cranberry juice has a reputation for being tart, acidic, and often sugary, qualities that might seem poorly suited to protecting teeth. A small human study from the University of Illinois Chicago, however, found that unsweetened pure cranberry juice was associated with slower dental plaque regrowth and lower acid production.

UIC College of Dentistry researcher Christine Wu examined whether compounds naturally found in cranberries could affect dental plaque bacteria, which feed on sugars and produce acids that contribute to enamel decay. Cranberries contain proanthocyanidins, anti-inflammatory compounds known for their ability to interfere with the attachment of bacteria such as E. coli to cells.

“Just like sugar damage is linked to diet, I’m interested in how the food and beverages we consume can help combat the harmful bacteria and benefit our oral health,” Wu said.

Protein can help build and preserve muscle, but eating more has its limits

As with all food choices, put some thought into what you choose to eat

Dominic Farsi, Teagasc; King's College London; Queen's University Belfast

DON'T be this guy!

High protein content has become a selling point on foods ranging from breakfast cereals to yoghurts. For anyone hoping to build muscle or stay strong as they age, choosing the product with the most protein can seem sensible. But whether an extra serving will help depends on what they already eat and how they use their muscles.

Someone who regularly lifts weights may benefit from additional protein to support muscle growth. An older person with a small appetite may need help getting enough to maintain strength. Someone already eating enough protein may gain little from adding more.

Understanding those differences can make it easier to decide whether to change your diet, buy a supplement or concentrate on exercise.

Muscle tissue is continually being broken down and rebuilt. Dietary protein supplies amino acids, the small molecules the body uses to make its own proteins, including those in muscle.

Resistance exercise makes muscles work against a load. That load might come from weights or from your own body during an exercise such as press-ups. It stimulates the processes involved in building and repairing muscle, allowing muscles to adapt to repeated demands.

Protein supports this adaptation, but increasing intake does not reproduce the effects of exercise.

A review of 49 trials involving 1,863 participants found that protein supplements produced additional improvements in muscle size and strength during resistance training. Participants were training for at least six weeks. The findings therefore concern protein’s contribution to a training program, rather than the effects of adding a shake to an otherwise unchanged routine.

For someone already eating enough protein, establishing a manageable strength-training routine may be more useful than searching for another high-protein snack.

Now is the time to get your flu shot.

Experts say don't wait. 

Sarah Boden

Influenza season started early this year, and Americans are advised to get their flu shots now, even in the parts of the United States where activity is currently low.

Nearly 5,000 lab-confirmed influenza hospitalizations were reported nationwide during the week ending October 17, according to the Centers for Disease Control and Prevention (CDC). 

This is the highest early-season hospital rate for mid-October since the 2010-11 flu season, said Anna Durbin, MD, director of the Johns Hopkins Center for Immunization Research, during today's media briefing. 

Early cases seem driven by an H1N1 variant, a type of influenza A, for which data suggest this year's vaccine is an incomplete match. Even so, the vaccine can prevent severe illness.

Preliminary CDC estimates find that up to 81,000 US residents died of flu-related illness from October 1, 2025, through May 23, 2026.

Additionally, the shot protects against two other flu viruses: another influenza A strain and a B lineage flu virus. Both are expected to circulate widely later this respiratory virus season. 

Because the vaccine works best before flu activity starts, people should get it as soon as possible, said Andrew Pekosz, PhD, co-director of the Johns Hopkins Center of Excellence in Influenza Research and Response.

"This [moment] should be viewed as a good last call," he said.

EDITOR'S NOTE: I got my COVID and flu shots at CVS in Westerly on October 23. As a determined PRO-vaxxer, I get whatever shots are available to ward off life-threatening illness. I made an advance appointment and was seen exactly at the time of that appointment. I was too early in the season to get the new mRNA-based flu shot. That will have to wait until next year. In the past, the mRNA COVID vaccine has caused me to undergo a day-after reaction where I feel sick for a couple of hours. But for the second year in a row, I had no negative after-effects. I have never had COVID and no flu or RSV since getting the shots.   - Will Collette

A single sauna session sends immune cells surging through your body

Feeling sick? Finns say hop in the sauna

University of Eastern Finland

Bobby Kennedy Jr. and Kid Rock do sauna
workout. In blue jeans.

A new Finnish study reveals that just 30 minutes in a sauna can temporarily flood the bloodstream with additional white blood cells, potentially helping the immune system patrol the body and detect threats. The surprising response resembles the immune boost seen during exercise and may help explain some of the health benefits linked to sauna bathing.

During the study, researchers observed an increase in every type of circulating white blood cell they measured. Among them were neutrophils and lymphocytes, two important groups of immune cells. Neutrophils are often among the first defenders to respond to an infection, while lymphocytes include cells that recognize specific threats, produce antibodies, and help coordinate immune responses.

The increase was temporary. Within 30 minutes after the sauna session, neutrophil and lymphocyte counts had returned to their original levels.

World-First Cancer Vaccine Cuts Melanoma Recurrence or Death Risk by 42% in Landmark Trial

Zeroing in on a skin cancer vaccine

By Carly Cassella

It's been 20 years since Australian researchers created the world's first vaccine developed specifically to prevent cancer.

Thanks to the HPV vaccine, Australia is on track to become one of the first nations in the world to eliminate cervical cancer.

Now, research led by scientists Down Under has made another breakthrough – this time for skin cancer.

The first personalized mRNA cancer vaccine has now succeeded in a phase 3 clinical trial, reducing the risk of melanoma returning or causing death by 42 percent compared with standard immunotherapy alone.

The results are even better than scientists were expecting.

The global principal investigator, medical oncologist Georgina Long from Melanoma Institute Australia (MIA), presented the results at the European Society for Medical Oncology Congress 2026.

They are set to be published in the New England Journal of Medicine.

Scientists found that 10 different healthy diets were linked to slower biological aging

There's more than one way to eat your way toward healthier aging

DZNE - German Center for Neurodegenerative Diseases

A large study involving approximately 7,500 people suggests that eating a healthy diet may help slow biological aging, and there is no single eating plan that stands above all others. Scientists at the German Center for Neurodegenerative Diseases (DZNE) investigated 10 different dietary patterns, including the Mediterranean, Nordic, plant-based, and DASH diets. The DASH diet was specifically developed to help reduce blood pressure.

Every dietary pattern examined was associated with slower biological aging, as measured by chemical changes in DNA that reflect the body's aging process. The findings were first identified using data from DZNE's Rhineland Study and then independently confirmed in another population. The research was published in Nature Communications.

"Our study suggests that healthy eating goes hand in hand with slower biological aging. The effects are not massive, but they are measurable and relevant for prevention. By slowing the aging process, the risk of age-related diseases such as dementia or cardiovascular disorders can be reduced. Thus, healthy eating contributes to healthy aging," says Prof. Monique Breteler, Director of Population Health Sciences at DZNE and head of the Rhineland Study. 

"Importantly, there is probably no single 'correct' diet. According to our data, various dietary patterns are associated with slower aging, some more, some less. That is an encouraging finding, because it leaves room to tailor healthy eating to personal and cultural preferences, budget and taste."

‘Voting is medicine’: These health professionals want you to vote in the midterms

Your vote matters

By Neha Pathak, Yale Climate Connections

When wildfire smoke drifts over a city or a heat wave blankets a community, doctors and nurses see the results firsthand. Asthma attacks, heart attacks, strokes, and heat-related illnesses surge.

Dr. Cynthia Mahoney, a retired California internist and nephrologist, helps lead Climate Health • Civic Health, an all-volunteer alliance of health professionals and organizations, alongside colleagues Margie Chen and Karina Maher.

Yale Climate Connections spoke with Mahoney about how climate change affects our health, why data centers have galvanized action, and what readers can do leading into Election Day.

The interview has been edited for length and clarity.

Yale Climate Connections: How does climate change affect people's health?

Dr. Cynthia Mahoney: Climate disruption and fossil fuel pollution impact our health from cradle to grave, and it's going to get much worse unless we change course now.

Think of a worker who collapses in 105-degree heat and ends up in the hospital. That's going to get worse. That's climate change.

What's so unique about climate change is that it's going to impact all of us. It puts us all in this together.

YCC: You practiced in intensive care units. Does that shape how you see this problem?

Mahoney: I was trained as a nephrologist and practiced a lot in ICUs. What I prided myself on was not just treating what I saw in front of me, but asking, "Where is this patient going? How do I intervene now to keep them from deteriorating?"

This is an ICU moment. The health of the people on Earth needs ICU-level care. We see where this is heading, and we need to intervene.

YCC: Why do you want people to vote?

Mahoney: Democracy is the way we change direction.

A lot of young people think, "Look what I've lived through. Voting hasn't helped me. Why should I bother?" Some people are cynical: The politicians are just in it for the money. There may be some truth to part of that. But that is furthering the goals of the people who are trying to corruptly extract our health from us. If voting wasn't important, they wouldn't be trying that hard to suppress it.

Scientists Say the Secret to a Happier, Healthier Society May Begin in Childhood

How children are raised may matter for social well-being worldwide

By University of Nottingham

Psychiatric professional Mary Trump, Donald Trump's
niece, blames Trump's father for son's mental problems

At home, a child seeking comfort depends on a caregiver’s response, while time for free play offers room to explore. A University of Nottingham-led study linked these experiences, along with a positive emotional atmosphere at home, to well-being years later. 

Positive childhood experiences were generally stronger predictors of adult well-being than the absence of negative ones, suggesting that avoiding harm captures only part of what matters.

Across the United Kingdom, the United States, and Japan, adults’ reports of supportive childhood experiences were associated with better health, greater happiness and life satisfaction, and lower anxiety. 

The connections extended to how people felt about those around them, including their satisfaction with social relationships, sense of belonging in their neighborhoods, and trust in others. Published in the Journal of Happiness Studies, the findings were consistent across substantial cultural differences and remained statistically significant after accounting for demographic factors such as income and education.

Plea from a father who lost his 5 year old daughter to flu

Sometimes it’s not ‘just the flu’

Zachary Yaksich

Alana Yaksich. Photo courtesy of JoAnna Yaksich

In 2003, my life was completely shattered. My daughter, Alana, was 5½ years old when she died from complications of influenza.

My family and children had received all of their childhood vaccinations on schedule and as recommended by the Centers for Disease Control and Prevention (CDC), but in 2003, the age recommendation for influenza vaccination was 6 months through 59 months. 

Alana was older than that. She had not received a flu vaccine, nor had her pediatrician ever recommended one to us or explained the dangers that influenza could pose to a child.

Until Alana died, I had no idea that the flu could kill. Like so many people, I thought of influenza as a miserable but relatively routine illness—something that would make you feel awful for a few days and then eventually pass. I was wrong. It often is that way, but far too often for grieving parents and families, it can be much worse.

A new study changes the conversation

A recently published study in the American Academy of Pediatrics journal Pediatrics, titled “Influenza Vaccine Effectiveness Against Pediatric Death in the United States: 2016–2025,” provides some of the most compelling evidence yet about what influenza vaccination can mean for children.

Conducted by CDC researchers, the study examined pediatric influenza deaths in the United States over nearly a decade. Its conclusion deserves the attention of every parent: Influenza vaccination reduced the risk of fatal influenza among children with and without known underlying medical conditions. Influenza vaccine was 80% effective in preventing deaths overall, with 77% among children with underlying medical conditions and 87% among children without such conditions.

Why is this more important than ever?

The internet and social media have made it easy for misinformation to spread. People can find almost anything online to reinforce what they already believe, including information that contradicts decades of scientific evidence.

Head-to-head comparison of three mRNA vaccines reveals differences in their stability in human blood

mRNA vaccine development to fight cancer

By Olivia Newton-John Cancer Research Institute

Edited by Sadie Harley, reviewed by Robert Egan

Photo by Spencer Davis on Unsplash

A study by Australian researchers compared three mRNA-LNP vaccine platforms in human blood samples, generating findings that could advance cancer treatment and vaccine design.

mRNA-lipid nanoparticles (LNPs) transformed the way that vaccines are delivered to humans when they became widely used during the COVID-19 pandemic.

mRNA-LNPs are tiny parcels, ~800 times smaller than the width of a human hair, made of fatty acids (lipids) and containing cargo (messenger RNA) that needs to be delivered inside the body to generate a treatment response (for example, immunity to a virus).

Today, researchers around the world are investigating mRNA-LNPs as candidates for "cancer vaccines" that would deliver mRNA cargo to boost the patient's immune system and empower it to kill cancer more effectively.

Report Details How Trump Duped His MAHA Base by Appeasing Corporate Interests

Toxic Betrayal

Julia Conley for Common Dreams

It’s been seven months since more than 30 leaders of the “Make America Healthy Again” movement told the Trump administration that they were losing patience, and demanded to see evidence that the US Environmental Protection Agency took seriously millions of Americans’ concerns about toxic “forever chemicals” and microplastics.

“MAHA is a mandate, not a marketing campaign,” the advocates told EPA Administrator Lee Zeldin, calling for an end to both corporate-friendly loopholes in regulations and the “revolving door” that saw chemical lobbyists hired by the agency tasked with regulating the industry.

But on Monday, the government watchdog Public Citizen revealed that 20 out of 21 environmental chemicals that the White House pledged to address in its May 2025 “MAHA Report” have been subject to less, not more, regulation under the Trump administration.

For nine of the chemicals, including the carcinogenic herbicide atrazine, mercury, and per- and polyfluoroalkyl substances (PFAS)—often called forever chemicals—President Donald Trump and his top officials have loosened public health regulations.

For 10 of them, the administration has taken none of the action promised in the MAHA Report, and in the case of the cancer-causing herbicide glyphosate, Trump issued an executive order not only endorsing the use of the chemical but mandating its production—a year after Bayer, the parent company of the chemical firm that uses glyphosate in popular weedkiller Roundup, donated $1 million to Trump’s inaugural campaign.

Public Citizen found just one substance, microplastics, for which the administration has “taken any step toward regulation, and at best it was a baby step”—announcing in April that microplastics may be considered for regulation in the future and that the government would study measuring and removing them from the human body.

New Lancet study links 12% of global cancer cases to 12 infectious diseases

For most such infections, there are vaccines or vaccines in development

NEWSROOM CLARIN

Let's add preventable cancers to this list

The worldwide incidence analysis, conducted by epidemiologists at the World Health Organization’s International Agency for Research on Cancer (IARC), evaluated 12 infectious agents classified as Group 1 human carcinogens. 

The findings demonstrate that roughly 1 in every 8 cancers diagnosed globally is linked to an underlying infection, representing a substantial cancer burden that could be prevented or mitigated using existing vaccines, diagnostic screenings, and antimicrobial therapies.

The global proportion of infection-attributable cancers has remained essentially unchanged since the agency's previous assessment in 2018 (which estimated 13%), highlighting persistent gaps in worldwide vaccination uptake, screening infrastructure, and therapeutic access.

The 12 Pathogens: Which Infections Cause Cancer?

The vast majority of infection-driven cancers in 2024 were concentrated among five primary pathogens, with two leading agents responsible for more than 1.5 million cases:

• Helicobacter pylori (760,000 cases / 4% of all global cancers): A common bacterium that colonizes the stomach lining, typically transmitted through contaminated food, water, or poor hygiene. It is the leading cause of non-cardia gastric cancer (accounting for 700,000 cases, or 85% of all non-cardia stomach cancers) and causes cardia gastric cancer (42,000 cases) and gastric non-Hodgkin lymphoma (18,000 cases).
• Human Papillomavirus / HPV (750,000 cases / 4% of all cancers): The primary driver of cervical cancer, which accounted for 600,000 cases (100% attributable to HPV). HPV is also responsible for 58,000 cases of oropharyngeal, tonsil, and base-of-tongue cancers, 32,000 anal squamous cell carcinomas, 18,000 penile cancers, 14,000 vaginal cancers, and 12,000 vulvar cancers.
• Hepatitis B Virus / HBV (360,000 cases / 2% of all cancers): Contracted through blood, sexual contact, contaminated needles, and perinatal transmission from mother to child. It accounts for 330,000 cases of hepatocellular carcinoma (primary liver cancer) and 27,000 cases of intrahepatic cholangiocarcinoma.
• Epstein-Barr Virus / EBV (260,000 cases / 1% of all cancers): A ubiquitous herpesvirus carried by more than 90% of adults. It was linked to 110,000 cases of nasopharyngeal carcinoma, 78,000 cases of gastric adenocarcinoma, 47,000 cases of Hodgkin lymphoma, 20,000 cases of diffuse large B-cell lymphoma, and 6,200 cases of Burkitt lymphoma.
• Hepatitis C Virus / HCV (160,000 cases): A bloodborne virus causing chronic hepatitis, responsible for 130,000 cases of hepatocellular carcinoma, 17,000 cases of non-Hodgkin lymphoma, and 11,000 cases of intrahepatic cholangiocarcinoma.
• Kaposi's Sarcoma-Associated Herpesvirus / KSHV (35,000 cases): Responsible for 34,000 cases of Kaposi's sarcoma and rare primary effusion lymphomas.
• Other Classified Infectious Agents (19,000 cases combined): Human T-cell lymphotropic virus type 1 (HTLV-1, causing 3,900 cases of adult T-cell leukaemia/lymphoma); Schistosoma haematobium (a parasitic waterborne flatworm causing 5,900 bladder squamous cell carcinomas); liver flukes Opisthorchis viverrini and Clonorchis sinensis (causing 3,800 bile duct cancers); Merkel cell polyomavirus (causing 3,200 aggressive Merkel cell skin carcinomas); and HIV (which directly caused 2,300 cases of conjunctival eye cancer and contributed via immunosuppression to tens of thousands of HPV- and KSHV-related cancers).