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In South Korea, health officials are trying to control an outbreak of MERS, the deadly respiratory disease. There are now 30 confirmed cases and two deaths. More than a thousand people are under quarantine in the country, with dozens more being monitored in Hong Kong and China. NPR global health correspondent Jason Beaubien reports.
JASON BEAUBIEN, BYLINE: The disease called Middle East Respiratory Syndrome is causing panic in South Korea. Late last month, a businessman returning from Saudi Arabia was diagnosed as Korea's first case. Now people are snapping up face masks and wearing them in an attempt to protect themselves from a potentially fatal respiratory disease. But most people who've come down with MERS didn't get it walking down the street. Most got it in a hospital. Twenty-five of the cases in Korea are linked to the hospital where the country's first MERS patient was treated.
MICHAEL OSTERHOLM: It's not surprising that we see outbreaks in the health care setting.
BEAUBIEN: Michael Osterholm is the director of the Center for Infectious Disease Research and Policy at the University of Minnesota.
OSTERHOLM: When you have someone who is infectious with a respiratory illness and you put them in a setting where they are other sick people, unless you're able to completely control where that air goes from that person who is infected and breathing, you're likely to infect other people who are also sick and more likely to be vulnerable to the virus.
BEAUBIEN: The country that's been hardest hit by MERS is Saudi Arabia. There have been more than a thousand cases and 449 deaths from MERS in the kingdom since MERS was first identified in 2012. And many of the Saudi MERS cases were in hospitals, but it's still not even entirely clear how the virus spreads. Can it linger in a room for hours? Does it spread because virus particles cling to doorknobs or linens? One hospital in eastern Saudi Arabia had an outbreak that mainly hit people on dialysis. Dr. Trish Perl, an epidemiologist at Johns Hopkins, investigated MERS cases at four Saudi hospitals in 2013.
TRISH PERL: In health care settings, we're commonly doing procedures that also may facilitate what we call aerosolation (ph).
BEAUBIEN: Procedures such as putting a patient on a ventilator.
PERL: Really generating clouds of viral-laden particles that can be more readily transmitted to health care workers or to other patients.
BEAUBIEN: What's unusual about the current MERS outbreak in Korea is that it's so large. There have been other cases imported into Europe, the Philippines, North Africa and even two into the United States, but none of those caused major outbreaks. Perl says we don't know why the Korean outbreak has been so large, in part because, until now, there hasn't been the funding, access or political will to study MERS.
PERL: This is, you know, almost the third year that we've actually seen this. And there's really minimal data about the epidemiology and its transmission and what we call the transmission dynamic of this particular organism.
BEAUBIEN: Perl says the public health measures that Koreans are using - searching for people who may have been exposed, placing high-risk people in quarantine, isolating anyone who tests positive - should get this outbreak under control. But what keeps her up at night is how little scientists know about MERS. Could the virus be mutating? How soon until there's an effective treatment? Are some MERS patients more contagious than others? She hopes this Korean outbreak will motivate the global public health community to get those answers. Jason Beaubien, NPR News. Transcript provided by NPR, Copyright NPR.