美国国家公共电台 NPR When A Mystery Outbreak Strikes, Who You Gonna Call?（在线收听）

DAVID GREENE, HOST:

I think we might call this next story CSI Diseases. At the Centers for Disease Control and Prevention, there is a group of doctors. They call themselves the Epidemic Intelligence Service. They're basically disease detectives, and they've developed this reputation around the world as the team local health officials can turn to when faced with a mysterious outbreak. Here's NPR's Jason Beaubien.

JASON BEAUBIEN, BYLINE: In late April of last year, people who'd gathered for a funeral in a small port city in Liberia started getting violently sick.

JAYMIN PATEL: There were these cases that showed up at a hospital, and a good amount of them were either dead on arrival or had a severe manifestation of a disease.

BEAUBIEN: Jaymin Patel is an epidemic intelligence officer with the CDC based out of Atlanta. The first reports of the outbreak were that 10 people who'd been at the funeral were admitted to a hospital in Greenville, Liberia, and within hours, five of them were dead.

PATEL: The level of concern was very high.

BEAUBIEN: The most common symptoms were vomiting, diarrhea and severe stomach cramps. Some of the patients had a fever. Rumors started to spread.

PATEL: I think a lot of people were thinking was, like, is Ebola back?

BEAUBIEN: Ebola, which had killed nearly 5,000 people in Liberia just a few years earlier. So tissue samples from several of the funeral attendees were collected and sent to the Liberian Ministry of Health's lab to be screened for Ebola. They tested negative.

PATEL: And so people thought, like, maybe it is a non-infectious cause of the outbreak, like toxic poisoning or something that was consumed.

BEAUBIEN: The CDC's Epidemic Intelligence Service has a two-year postgraduate training program. CDC officers get field experience. Local health officials get access to a rapid response force for disease outbreaks. With the case in Liberia, samples of blood, urine and saliva were shipped to the CDC's headquarters in Atlanta. The samples were screened for heavy metals, insecticides and dozens of infectious agents. Finally, the CDC lab isolated the culprit, a bacteria that was causing meningococcal blood infections. In the end, the mystery was solved, but only after 31 people got sick and 13 died. Tolbert Nyenswah, the director general of the National Public Health Institute of Liberia, says this is a rare disease for his country. And prior to this outbreak, Liberia didn't have the sophisticated laboratory equipment needed to screen for it.

TOLBERT NYENSWAH: It would have been difficult to be detected because our lab didn't have the capacity to do that. And so CDC coming in was very helpful.

BEAUBIEN: Now Liberia has the equipment it needs to test for this disease in the future. Currently, the CDC has 149 Epidemic Intelligence Officers in the two-year program. They're just as likely to get called in to help with an outbreak in Ohio as in Africa. Last year other CDC disease detectives probed the cause of food poisoning at a chili and chowder cook-off in Virginia. They tested cooling systems in New York City for Legionnaires' disease. They analyzed exposure to MERS virus among workers at a camel market in the United Arab Emirates. Caitlin Cossaboom got sent to investigate a massive wildlife die off in Namibia, and she had to take tissue samples from bloated, rotting hippo carcasses.

CAITLIN COSSABOOM: Even just with the few carcasses that I was working with, the smell was really incredible.

BEAUBIEN: Cossaboom helped confirm that it was actually anthrax that was killing the wildlife. She brought a new anthrax diagnostic machine with her. Like so many of the disease detectives, she got hands-on experience with a rare infectious agent. Namibian officials got help with the investigation and access to cutting-edge, new diagnostic technology. And that sort of sums up what this program does. It provides assistance in a time of crisis to local health officials, and in return, CDC epidemiologists get valuable experience in the field.

Jason Beaubien, NPR News.