Public health became a political battleground in 2025. Under Health Secretary Robert F. Kennedy Jr., a longtime vaccine skeptic, federal health agencies changed course on vaccines and raised claims that many scientists dispute, while measles spread at levels not seen in a generation. At the same time, researchers reported promising advances — including an unexpected possible benefit of Covid vaccines for cancer patients.

Measles returns

What happened

A measles outbreak that began in West Texas in January 2025 spread across several states. The U.S. recorded 2,242 confirmed cases in 2025, the most since 1992 (NPR, via OPB), and more than 3,800 from January 2025 through March 2026 (KFF). The disease also surged across Latin America, where cases rose roughly 34-fold in 2025 as outbreaks in North America spread south and governments launched mass vaccination campaigns. Doctors in the region blamed falling vaccination rates and anti-vaccine messaging, much of it amplified by U.S. politics.

Why "elimination status" matters

The U.S. declared measles eliminated in 2000, meaning the virus no longer circulated continuously. A country loses that status if the same strain spreads for 12 months or more. Canada lost its status in November 2025. The Pan American Health Organization downgraded the U.S. to "sustained with major concerns" and has postponed its formal review to November 2026 (PAHO). U.S. health officials argue the outbreaks were separate chains of transmission.

The Tylenol claims

What was said

In September 2025, President Donald Trump and Kennedy urged pregnant women to avoid acetaminophen, the active ingredient in Tylenol, citing a possible link to autism. Major medical organizations said the research shows, at most, an association that does not prove the drug causes autism, and that untreated fever in pregnancy carries its own risks. Kennedy later acknowledged that the evidence was not sufficient to say acetaminophen definitely causes autism.

The Texas lawsuit

On Oct. 28, 2025, Texas Attorney General Ken Paxton sued Johnson & Johnson and Kenvue, the company that now makes Tylenol, accusing them of hiding risks from pregnant women (Gray, via Fox 8). A Texas judge refused Paxton's requests to immediately bar Kenvue's safety claims and to block its shareholder dividends (Texas Public Radio), but in February 2026 she denied Kenvue's motion to dismiss the case, allowing it to proceed (HarrisMartin). Kenvue says the claims lack legal merit and scientific support.

A surprising finding about mRNA vaccines

In October 2025, researchers at MD Anderson Cancer Center reported in Nature that patients with advanced lung cancer or melanoma who received an mRNA Covid-19 vaccine within 100 days of starting immunotherapy lived significantly longer than those who did not. Among lung cancer patients, median survival rose from about 21 months to 37 months. The vaccines appear to rev up the immune system in a way that helps immunotherapy drugs work. Because the study looked back at medical records rather than randomly assigning treatments, the researchers have planned a randomized trial to confirm the effect (CancerConnect; U.S. Pharmacist).

A new way to delay type 1 diabetes

In June 2026, England became the first European country to approve teplizumab (sold as Tzield by Sanofi) through its national health technology review. The drug, an immunotherapy, can delay the onset of symptomatic type 1 diabetes by almost three years in people aged 8 and older who have early-stage disease but no symptoms yet. It will be offered through the National Health Service.

Where things stand now

  • Measles: PAHO's review of U.S. elimination status is scheduled for November 2026.
  • Tylenol: The Texas lawsuit is proceeding; private lawsuits against Kenvue continue.
  • mRNA and cancer: A randomized trial is planned to test whether Covid vaccines should be given alongside immunotherapy.

Sources