Richard Knox

A vaccine against human papillomavirus — the most common sexually transmitted infection and the cause of almost all cervical cancer — is dramatically reducing the prevalence of HPV in teenage girls.

The first vaccine against HPV, Merck's Gardasil, was approved by the Food and Drug Administration in 2006. Cerverix, from GlaxoSmithKline, was approved in 2009.

It's been eight months since a Saudi Arabian doctor described a previously unknown virus related to SARS. And for most of that time only germ geeks paid much attention.

But in the past few days the new virus — which some would like to call MERS-CoV, for Middle East Respiratory Syndrome Coronavirus — has been making up for lost time.

The work is only in mice so far, but it sure is intriguing.

A newly found hormone revs up production of cells that make insulin — the very kind that people with advanced diabetes lack.

Boston hospitals always staff up their emergency rooms on Marathon Day to care for runners with cramps, dehydration and the occasional heart attack.

But Monday, those hospitals suddenly found themselves with more than 100 traumatized patients — many of them with the kinds of injuries seen more often on a battlefield than a marathon.

Like most big-city hospitals these days, Tufts Medical Center runs regular disaster drills, featuring simulated patients smeared with fake blood.

Sixteen cases of a new flu around Shanghai have touched off a major effort to determine what kind of threat this new bug might be.

The victims range in age from 4 to 87 years old. Six have died. It is a tragedy for them and their families, but is it a global crisis?

To understand why so few cases are generating so much concern, the first thing to know is that no flu virus like this one — called H7N9 — has ever been known to infect humans before.

It's not the first study that finds the lowly aspirin may protect against the deadliest kind of skin cancer, but it is one of the largest.

And it adds to a mounting pile of studies suggesting that cheap, common aspirin lowers the risk of many cancers — of the colon, breast, esophagus, stomach, prostate, bladder and ovary.

The World Health Organization says a new coronavirus has killed two people in Jordan — the third country where the novel microbe has been traced.

That brings lab-confirmed cases to nine, with five fatalities.

It's a troubling story authorities think will unfold over the next month or so. An untold number of Americans who got steroid injections in their spine to relieve back pain may end up with a rare fungal meningitis. The drug was contaminated with the spores of a common leaf mold — nobody knows how.

So far, the Centers for Disease Control and Prevention has recorded 35 cases of the fungal meningitis in six states: Tennessee, North Carolina, Florida, Virginia, Maryland and Indiana. Five patients have died.

Scientists have known for a while that breast cancer is really four different diseases, with subtypes among them, an insight that has helped improve treatment for some women.

But experts haven't understood much about how these four types differ. A new report, published online in the journal Nature, provides a big leap in that understanding.