The largest U.S. measles outbreak in recent history isn't the one that started in December at Disneyland. It happened months earlier in Ohio's Amish country, where 383 people fell ill after unvaccinated Amish missionaries traveled to the Philippines and returned with the virus.

The Ohio episode drew far less attention, even though the number of cases was almost four times that of the Southern California outbreak, because it seemed to pose little threat outside close-knit religious communities.

A high-security federal laboratory made a frightening mistake in sending certain Ebola samples to a lab with fewer safeguards, but an investigation concludes that the samples probably did not contain live virus.

The Centers for Disease Control and Prevention on Wednesday released the results of its internal investigation of the December 22 incident in Atlanta.

U.S. researchers have found a way to turn a common smartphone into a quick and easy device to conduct field tests for HIV and syphilis.

Using an attachment that costs $34 to make -- a far cry from the standard $18,000 for diagnostic tests -- blood drops are tested for the diseases' antibodies in minutes instead of hours, said the research led by Columbia University engineers.

Lung cancer is now the leading cause of cancer death among women in developed nations, beating out breast cancer which had long been the top killer, researchers said Wednesday.

The new analysis was led by researchers at the American Cancer Society in collaboration with the International Agency for Research on Cancer (IARC) in France.

One in two British people will develop cancer at some point in their lives, according to a new forecast by Cancer Research UK released on Wednesday.

The forecast replaces a previous estimate that one in three would suffer cancer, which the charity found to be an underestimate.

Japanese health authorities said on Wednesday that they will soon make a decision on a possible penalty against the local unit of Swiss pharmaceutical giant Novartis for failing to report drug side effects.

That followed media reports which said regulators would slap a 15-day suspension order on the firm, meaning the company could not sell most of its drugs during the two-week period -- a first for a pharmaceutical firm operating in Japan.

Colorado lawmakers struggling to make sense of incomplete scientific evidence about marijuana use by pregnant and nursing women have scrapped a bill to add warnings in pot shops about maternal marijuana use.

Lawmakers rejected a bill that would have required dispensaries to post signs warning about "dangers to fetuses caused by smoking or ingesting marijuana while pregnant." They heard testimony from women who used marijuana to treat nausea during pregnancy, but also from doctors who called for additional warnings.

Britain's Wellcome Trust said that clinical trials it was funding for a new Ebola treatment in Liberia were halted on Tuesday due to a fall in new cases.

"The current position is that there is no realistic prospect of the trial enrolling sufficient patients to be able to reach a conclusion about the efficacy of the drug," the Wellcome Trust, Britain's biggest scientific research charity, said in a statement.

Bottles of Walmart-brand echinacea, an herb said to ward off colds, were found to contain no echinacea at all. GNC-brand bottles of St. John's wort, touted as a cure for depression, held rice, garlic and a tropical houseplant, but not a trace of the herb.

In fact, DNA testing on hundreds of bottles of store-brand herbal supplements sold as treatments for everything from memory loss to prostate trouble found that four out of five contained none of the herbs on the label. Instead, they were packed with cheap fillers such as wheat, rice, beans or houseplants.

Britain on Tuesday became the first country in the world to allow the creation of babies with DNA from three people after MPs voted for the controversial procedure.

Lawmakers at the House Commons voted by 382 to 128 in favor of allowing the creation of in-vitro fertilisation (IVF) babies with DNA from three people, a move aimed at preventing serious inherited diseases being passed on from mother to child.