Rob Stein

The Centers for Disease Control and Prevention is investigating 252 cases of acute flaccid myelitis and has confirmed 90 cases. One or more viruses is suspected, but CDC says the cause is unknown.

After a C-section, does swabbing a baby with the mother's microbes reduce the risk of obesity and other health problems later in life? An ambitious study to help answer the question is underway.

A majority of Americans of European descent could be linked to third cousins, or closer relatives, using genealogy databases, a study finds. Soon it may be possible to identify nearly everyone by DNA.

A study involving 2,000 women age 65 and older found that a commonly used drug for osteoporosis could reduce the risk for broken bones in women at an earlier stage of bone thinning.

Scientists demonstrate that a "gene drive" can rapidly spread a genetic mutation through a species, perhaps providing a potent new weapon against malaria. But there are plenty of skeptics.

A Japanese research team made immature human eggs from stem cells that were derived from human blood. The technique brings scientists a step closer to being able to mass-produce human eggs.

A new study found that the risks apparently outweigh the benefits of taking a low-dose aspirin every day for otherwise healthy older people. But what about everyone else?

Results from a large international study show that risks from taking daily low-dose aspirin outweigh the potential benefits for older people in generally good health.

After trying one treatment after another for his leukemia, 20-year old Aaron Reid enrolled in a study to test an experimental therapy using modified cells from his own body.

The Food and Drug Administration said teen vaping has reached epidemic proportions, prompting more than 1,300 warning letters to stores selling e-cigarettes to kids and an ultimatum to four companies.

Consumers will have a new generic alternative to the widely used — and pricey — device to counter life-threatening allergic reactions.

Researchers are working on better ways to teach patients' immune systems to root out and kill malignant cells. A promising approach involves cells that attack cancer two ways at one time.

The largest study to follow women infected with Zika while they were pregnant finds about 6 percent of children had problems at birth, but 14 percent had complications by their first birthday.

Two drugs appear to support immune function of elderly people and may be important for future research into anti-aging treatments.

Duke University researchers say some patients with brain cancer survived long after receiving treatment with a weakened poliovirus. But the response rate was limited and there were side effects.

As home genetic testing continues to boom, more people are getting their DNA tested for health reasons. The tests may signal future disease, but there are many limitations that might falsely reassure.

The U.S. Preventive Services Task Force says the benefits from routine electrocardiograms in people at low risk of heart disease don't outweigh the harms from unnecessary follow-up tests.

Several women who have had trouble conceiving children have gone to a clinic in Ukraine that is doing something unique: using DNA from three different people to create a healthy embryo.

We look at results after eight states had primary elections Tuesday. Also, Facebook gave data access to Chinese companies, and a look inside a controversial Ukrainian clinic making embryos.

A clinic in Kiev, Ukraine, stirs controversy by making babies with DNA from three different people to help women who are infertile bear children. It's the only clinic known to be doing this right now.