Hepatitis B Vaccination Linked to Reduced Diabetes Risk

Daily vaccinations for hepatitis B are administered worldwide

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The hepatitis B vaccine not only prevents infection but also appears to lower the chances of developing diabetes.

In most countries, infants receive this vaccine routinely, typically as part of a three-dose series. In the US, it was incorporated into vaccination schedules in 1991. By 2018, around 30% of adults were fully vaccinated.

Researchers previously noted that vaccination may decrease diabetes risk. This is related to hepatitis B, which infects the liver and is transmitted through blood, semen, and vaginal fluids – impairing the liver’s ability to manage glucose. Elevated blood sugar levels can lead to diabetes.

However, earlier studies didn’t investigate whether vaccination could lower diabetes risk in individuals who were not infected with hepatitis B.

To address this gap, Nhu-Quynh Phan from Taipei Medical University in Taiwan and her team examined health data from over 580,000 people across the US, Europe, Africa, Latin America, the Middle East, and Asia-Pacific. These records averaged almost four years for each individual, covering the period from 2005 to 2023.

Participants aged 18 to 90 had no types of diabetes and were not infected with hepatitis B. About half were vaccinated, determined by measuring virus-specific antibodies in their blood.

The study revealed that diabetes prevalence among vaccinated individuals was 15% lower than in the unvaccinated group, with most cases being type 2 diabetes, the most prevalent form. The findings will be shared at the upcoming annual meeting of the Diabetes Association in Vienna, Austria.

This observational study also indicated a dose-response correlation. Participants with higher levels of hepatitis B-specific antibodies were less likely to develop diabetes compared to those with lower levels. Variations in antibody levels might correlate with the number of vaccinations received, timing of immunization, or individual immune responses.

No participants were purposefully infected with hepatitis B, suggesting that vaccination not only wards off the virus but may also lower diabetes risk, Fan notes. One explanation could be that vaccines help alleviate chronic inflammation damaging the liver and pancreas, which produce hormones like insulin regulate blood sugar levels.

Nonetheless, researchers cannot dismiss the theory that some protective benefits of vaccines might stem from their role in preventing infections, she adds. They are keen to investigate credible pathways and how mouse models can elucidate distinctions between diabetes types, Fan states.

Vaccinated individuals might also engage in healthier lifestyle choices, such as maintaining a nutritious diet and staying active. “Those likely to get vaccinated often exhibit greater awareness of health,” states Albert Osterhouse from the University of Veterinary Medicine in Hanover, Germany.

The research team considered factors including participants’ age, gender, and lifestyle choices like smoking, along with conditions such as obesity and hypertension. However, Osterhouse emphasizes the difficulty in ruling out the impact of these variables.

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Source: www.newscientist.com

Essential Information on the Hepatitis A Outbreak in LA County

Los Angeles County public health officials have reported an outbreak of hepatitis A. This highly contagious liver infection is caused by a virus that can, in rare instances, lead to serious illness.

Typically, there are fewer than 50 cases annually in LA County, but at least 138 individuals were infected in 2024, with cases continuing to rise significantly in 2025. These numbers are incomplete.

Here’s what you should know.

The hepatitis A virus is spread via the oral-fecal route, meaning it can be ingested through food and beverages contaminated with microscopic stool from infected individuals. The virus can also be transmitted through close contact with someone harboring it, even if they show no symptoms.

Certain individuals face a higher risk of contracting hepatitis A due to inadequate access to clean toilets and handwashing facilities. It is more prevalent among travelers, in settings with poor hygiene, among men who have sex with men, and among drug users.

Officials note that many recent cases have appeared in individuals lacking these risk factors. The reasons remain unclear, but Dr. Timothy Brewer, an infectious disease specialist and epidemiologist at UCLA, is increasingly concerned about two issues: food contamination and community transmission.

“In a community with good hygiene and access to drinking water, we shouldn’t see high numbers of infections,” he remarked. “Something is happening, but we aren’t sure what it is.”

Initial symptoms include fever, fatigue, nausea, and loss of appetite, followed by vomiting and diarrhea. Infected individuals may subsequently develop jaundice, dark urine, and pale stools.

One significant challenge in controlling the spread of hepatitis A is that contact tracing can be quite challenging. The virus can incubate for up to seven weeks before symptoms appear, and carriers can transmit it for up to two weeks before they feel ill.

Moreover, many infected individuals do not exhibit severe symptoms, according to Dr. Edward Jones Lopez, an infectious disease specialist at Keck Medicine at the University of Southern California, which means they might not seek medical evaluation, undergo blood tests, or report their cases.

Severe symptoms are predominantly observed in the elderly, those with chronic liver diseases, and individuals with compromised immune systems or HIV. While fatalities from hepatitis A are rare, at least seven deaths have been linked to the outbreak. Officials suspect that the true number of infections is significantly higher than reported, as many individuals likely remain asymptomatic or have mild symptoms that go unrecognized.

There are no specific antiviral treatments for hepatitis A, as the infection typically resolves on its own within weeks without causing permanent liver damage. However, hospitalization might be necessary for some patients.

In rare instances, hepatitis A can lead to acute liver failure, known as fulminant hepatitis, which may necessitate a transplant, stated Dr. Jones Lopez. “It can escalate rapidly. It’s a serious condition.”

If you believe you may be infected, consult your doctor, stay hydrated, and rest adequately.

Vaccination is the most effective way to prevent hepatitis A. The vaccination schedule consists of two doses given at least six months apart, which provides substantial protection. While children have routinely received this vaccine for the past two decades, many adults over the age of 25 do not get vaccinated unless they belong to a high-risk group.

“Infection can occur anywhere,” warns Dr. Anne Limoyne, a professor of epidemiology at UCLA.

If you have been exposed to someone with the virus but haven’t been vaccinated, a prompt vaccination can prevent infection. Experts suggest that individuals with compromised immune systems may also benefit from receiving immunoglobulins. Practicing good hygiene, such as thorough handwashing with soap and water after using the restroom and before preparing food, is essential for everyone.

Source: www.nytimes.com