The World Health Organization expects cases of Middle East Respiratory Syndrome [wikipedia.org] (MERS) to spread in South Korea. 200 primary schools are being closed and 1,300 people have been quarantined [washingtonpost.com]:
Health officials announced Wednesday that five more people had been diagnosed, bringing the total infected with the virus to 30. Two patients have died. That makes the outbreak the largest outside the Arabian Peninsula, where the disease emerged in 2012. The virus, which primarily causes flu-like symptoms such as fever and cough, kills an estimated three to four out of every 10 patients infected.
The situation in South Korea has alarmed the global health community because the virus has spread so fast and wide from a single individual. Other countries have imported cases in the same manner but the virus infected only a few others.
How did MERS get to South Korea and why is it spreading so fast?
The first known case, called an "index" case, was reported on May 20. It involved a 68-year-old man who was returning from a 16-day business trip to four Middle Eastern countries. The man was asymptomatic during his return flight but was subsequently treated at two different out-patient clinics and two hospitals which created a lot of opportunities for the virus to spread. Health care workers did not suspect the man of having MERS so he was not put in isolation.
Others who have been infected include health care workers, other patients, family members and visitors. The World Health Organization reported that some of the cases were patients in the same room or ward as the man, and that their exposure may have been from 5 minutes to a few hours [who.int].
Two recent cases represent an alarming development — a third generation of transmission. That is, a patient who did not have contact with the index patient but came into contact with an intermediary who had been exposed to the virus. "That raised fears that infections could now spread exponentially from all people who test positive," Korea's JoongAng Daily reported [joins.com].