Hundreds of schools were preparing to close on Thursday in Korea because of fears over the Middle East Respiratory Virus, which has killed two people there and forced the quarantine of at least 1,300 after a man carried the virus there from the Middle East.
He was treated in at least one hospital before anyone suspected MERS and the virus spread to close relatives, hospital roommates and health care workers before anyone suspected what was happening.
The World Health Organization says 29 more people were infected. One of those cases traveled to Hong Kong and mainland China, carrying the virus there, also.
It’s just the type of scenario that world health officials have been worried about. But experts say so far, MERS is more of a nuisance than a pandemic threat.
“I don’t think it’s anything new or different,” said Dr. Allison McGeer of Mount Sinai Hospital in Toronto, one of the world’s top experts on MERS and similar illnesses.
“This is the largest outbreak of MERS outside the Middle East."
“It just sounds like they missed the first patient and then it takes you time and quite a lot of patience to catch everybody and get it under control.”
The World Health Organization says it’s keeping an eye on the outbreak. What would worry experts is if it looked like the virus was spreading more easily from one person to another. That could spark a pandemic.
MERS is a coronavirus, a distant relative of SARS — severe acute respiratory syndrome virus — which infected more than 8,000 people around the world and killed 774 before it was stopped in 2004. Careful monitoring and isolation of everyone who could have been in contact with a SARS patient is what stopped the virus.
MERS, so far, doesn’t seem to spread easily among humans. But since 2012, it’s infected at least 1,179 people and killed 442 of them.
It usually can spread from one person to a close contact or two, and very rarely, one of those contacts can infect someone else. That’s called tertiary transmission.
“There is evidence of limited tertiary transmission (three cases) among the cases,” WHO says.
“This is the largest outbreak of MERS outside the Middle East. Since the identification of the first laboratory confirmed case, aggressive contact tracing has been in place and as of 03 June 2015, 1,369 contacts are being followed and are in quarantine or isolation either at home or in state-run facilities.”
The 68-year-old man who brought the virus to South Korea had traveled in Saudi Arabia, Qatar, the United Arab Emirates and Bahrain — all but Bahrain are countries where MERS has spread. Then the 44-year-old son of one of the Korean patients ignored medical advice and went to China, becoming ill on the trip. Chinese authorities have quarantined 88 people.
McGeer and WHO say all of this happened before anyone suspected MERS. Now they hope that strict measures will control any more spread.
It’s not easy, McGeer points out.
“It really hinges on everybody watching for travel histories,” she told NBC News. “The index patient here clearly had a travel history and it clearly got missed.”
And, she noted, some people seem to spread the virus more easily than others, for reasons that are not fully understood.
“It could be a million other things."
Because MERS is a respiratory virus, it’s not easy to recognize.
“It could be a million other things,” she said. Once a person who has traveled to a high-risk country infects someone else who hasn’t, it becomes impossible to flag a possible case of MERS. “You are not going to do a lab test on everybody with respiratory disease,” McGeer points out.
WHO says 25 countries have reported cases of MERS, but 85 percent of cases have been in Saudi Arabia. Two people have been diagnosed with MERS in the United States. Both recovered.
There's no specific treatment for MERS. Patients get what's called supportive care — intravenous fluids, oxygen or a breathing tube if needed, and pain medications.
Experts still don't know why it's spreading in the Middle East. Camels can get the virus, but it's not entirely clear whether they are directly infecting humans, or if another route of transmission is involved. People with kidney disease, diabetes, lung diseases and conditions that compromise the immune system are most at risk.