Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:

Whooping Cough Shot May Halt Illness But Not Transmission, Animal Study Suggests

Baboons that were recently vaccinated against whooping cough don't get sick but still carry the infection in their throats and can spread the disease to unvaccinated baboons, according to a new study.

Researchers say the finding may help explain the recent dramatic rise in cases of whooping cough across the United States, which reached a 50-year high in 2012, The New York Timesreported.

The study was published Monday in the journal Proceedings of the National Academy of Sciences.

"When you're newly vaccinated you are an asymptomatic carrier, which is good for you, but not for the population," said study leader author Dr. Tod Merkel, a researcher in the Office of Vaccines Research and Review in the Food and Drug Administration, The Timesreported.

The study finding was surprising and could be important as scientists try to improve whooping cough vaccines for people, experts say.

Current whooping cough vaccines were introduced in the 1990s after an older version was found to cause side effects. However, the new vaccines begin to lose effectiveness after about five years, The Timesreported.

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European Morning-After Pill Ineffective in Heavier Women

The label on a "morning-after" emergency contraceptive sold in Europe will be changed to alert consumers that it is not effective in women who weigh more than 176 pounds.

The new warning on the label of Norlevo will also caution that the pill starts to lose its effectiveness in women heavier than 165 pounds, and is not recommended for anyone over this weight, CBS Newsreported.

"When we became aware that there appeared to be an impact on efficacy (linked to weight), we felt it was our ethical duty as a drug manufacturer to report it and be transparent," Erin Gainer, CEO of HRA Pharma, the French manufacturer of Norlevo, told the New York Daily News.

Norlevo is identical in formula to the over-the-counter Plan B One-Step emergency contraceptive sold in the United States. The U.S. maker of Plan B One-Step, Teva Pharmaceutical Industries, declined to comment on the issue when asked about it by the Daily Newsand Mother Jones, CBS Newsreported.

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FDA Tells Gene Testing Company to Halt Marketing

A company that offers genetic testing directly to consumers has been told to stop marketing its main DNA service until it receives approval from the U.S. Food and Drug Administration.

An FDA warning letter sent to Califoria-based 23andMe says the company has failed to provide adequate evidence that its Personal Genome Service provides accurate results. The letter was issued Friday and posted on the FDA's website Monday, The New York Timesreported.

The letter says the agency considers the service to be a medical device that requires approval.

"FDA is concerned about the public health consequences of inaccurate results from the PGS device," the letter states. "The main purpose of compliance with FDA's regulatory requirements is to ensure the tests work."

23andMe's service has been used by about half a million people. It claims to tell consumers whether they might be at increased or decreased risk for various diseases, among other things, The Timesreported.