Richard Knox

Port-au-Prince is about the size of Chicago. But it doesn't have a sewer system. It's one of the largest cities in the world without one.

That's a big problem, but never more so than during a time of cholera.

In the teeming city of Port-au-Prince, Haiti, millions of people have no reliable water supply.

Many of the underground pipes that did exist were ruptured by the 2010 earthquake. Many public water kiosks are dry.

Now there's fresh evidence that CT scans to detect early lung cancer belong on the short list of effective cancer screening technologies — at least for people at high risk.

Researchers conclude that spiral CT, which makes 3-D pictures of lungs, could reduce lung cancer deaths by 35 percent at a cost of $19,000 to $26,000 per year of life saved.

Malaria experts have been holding their breath and hoping it wouldn't happen. But it has.

Malaria parasites resistant to the last, best drug treatment, called artemisinin combination therapy, or ACT, are infecting people along the border of Thailand and Myanmar.

Nine national medical groups are launching a campaign called Choosing Wisely to get U.S. doctors to back off on 45 diagnostic tests, procedures and treatments that often may do patients no good.

Many involve imaging tests such as CT scans, MRIs and X-rays. Stop doing them, the groups say, for most cases of back pain, or on patients who come into the emergency room with a headache or after a fainting spell, or just because somebody's about to undergo surgery.

Norwegian scientists say as many as 1 in every 4 cases of breast cancer doesn't need to be found because it would never have caused the woman any problem.

It's a startling idea for laypeople (and many doctors) thoroughly indoctrinated with the notion that any breast cancer is medically urgent — and should be found at the earliest possible moment.

The typical first-time mother takes 6 1/2 hours to give birth these days. Her counterpart 50 years ago labored for barely four hours.

That's the striking conclusion of a new federal study that compared nearly 140,000 births from two time periods.

One big implication: Today's obstetricians may be rushing to do cesarean sections too soon because they're using an out-of-date yardstick for how long a "normal" labor should take.

The debate over coronary bypass surgery versus stenting goes back decades.

Studies have been inconclusive, but doctors and patients have voted with their feet in favor of the less-invasive procedure — clearing clogged arteries and propping them open with tiny scaffolds called stents.

U.S. doctors do at least two stenting procedures these days for every coronary bypass operation.

A hundred thousand people in Haiti are ready and waiting to get vaccinated against cholera.

The vaccine is sitting in coolers. Vaccination teams are all trained. Willing recipients are registered and entered into databases.

The impending mass vaccination project aims to show that vaccinating against cholera is feasible in Haiti. It has never been done in the midst of an ongoing cholera epidemic. So far, more than 530,000 Haitians have fallen ill with cholera, and more than 7,000 have died.

Condoms aren't just for men.

A second generation of female condoms, which was approved in 2009, is cheaper than the first version. Still, the condoms for women are a lot more expensive than those for males. And female condoms remain pretty unfamiliar to most people.

When Susy Mansfield needed a hip replacement in 2009, her orthopedic surgeon chose a relatively new and untested kind of artificial hip made entirely of metal.

"He said, 'You're young. Metal is good for younger people. It's going to last a lot longer,' " says Mansfield, who was 57 at the time.

The vaccine — $417,000 worth of it — is stacked high in refrigerated containers to protect it from the Haitian heat.

Hundreds of health workers are trained and ready to give the vaccine. They're armed with programmed smartphones and tablet computers to keep track of who has been vaccinated and who needs a second dose.

And 100,000 eager Haitians, from the teeming slums of Port-au-Prince to tiny hamlets in Haiti's rice bowl, have signed up to get the vaccine.

Researchers have nailed down something scientists, government officials and agribusiness proponents have argued about for years: whether antibiotics in livestock feed give rise to antibiotic-resistant germs that can threaten humans.

It's a new kind of brinksmanship for U.S. doctors: caring for patients with life-threatening diseases when the supply of critical drugs threatens to disappear.

The Food and Drug Administration says counterfeit Avastin, a costly drug cancer drug, has made its way to doctors in the United States.

Voters are hearing a lot about health care this year. Republicans want to make the 2012 elections a referendum on the health care law that President Obama signed two years ago.

That law was largely based on one that then-governor Mitt Romney signed into law nearly six years ago in Massachusetts.

Tropical diseases that have long been overlooked are getting their due.

An ambitious new push to eradicate, eliminate or control 17 scourges over the next eight years was just unveiled in London. The initiative brings together some of the world's largest drugmakers, health-oriented foundations and nongovernmental organizations. Governments from the developed world and the countries most affected by the diseases are also on board.

The bone-thinning disease called osteoporosis is a big problem for women past menopause. It causes painful spine fractures and broken hips that plunge many women into a final downward spiral.

So it seemed to make sense to monitor older women's bones on a regular basis to see when they need to start taking drugs that prevent bone loss and fractures. Since Medicare will pay for a bone-density scan every two years, that's what many women have been getting.

A year ago today, India saw its last recorded case of polio in an 18-month-old girl in West Bengal named Rukhsar Khatoon. She recovered without lasting paralysis.

One year without another case is an impressive milestone in the decades-long effort to wipe the poliovirus from the face of the planet. Only a few years ago, India reported more polio cases than anywhere else — as many as 100,000 cases a year.

Tuberculosis specialists in India have diagnosed infections in a dozen patients in Mumbai that are unfazed by the three first-choice TB drugs and all nine second-line drugs.

The doctors are calling them "totally drug-resistant TB," and the infections are essentially incurable with all available medicines.