Thirteen more people have been infected with MERS-CoV in South Korea, all them with hospital links to the country's first case, lifting the number of cases in the cluster to 25, according to official and media reports. Two of the patients have died, including one previously reported.
The cluster is the largest so far outside of Saudi Arabia, where infection control lapses and unrecognized infections have played a role in fueling MERS-CoV (Middle East respiratory syndrome coronavirus) outbreaks in hospital settings.
Case count soars
The World Health Organization (WHO), in three separate statements, posted details on 14 of the first cases, 11 of which were previously reported. They include a business traveler whose illness was detected last week after his arrival in China. In addition to the three new cases reported by the WHO, three new cases were reported by South Korea's government and media sources.
South Korea's index case involves a 44-year-old man who was hospitalized after returning from travel to several countries in the Middle East. The other cases all have links to healthcare settings where the man was treated. They include other patients hospitalized on the same ward, family members who visited sick family members on the ward, and healthcare workers.
Those six newly reported cases continue that pattern and include:
- A 35-year-old man who was hospitalized with a possible tuberculosis (TB) infection on the ward as the index patient, according to a WHO statement yesterday
- A 35-year-old son of a woman who was on the same ward as the index case, according to a WHO statement yesterday
- A 49-year-old man helped take care of his wife, an earlier lab-confirmed MERS-CoV patient, when she was hospitalized on the same ward as the index patient, according to a WHO statement today
- A 40-year-old man who was hospitalized on the same ward as the index patient, according to a translated government report and media sources
- A 45-year-old man who is the son of a patient who was hospitalized on the same ward as the index patient, according to a translated government report and media sources
- A 77-year-old woman who was on the same hospital ward as the index case
In addition, in a late-breaking development today that was picked up and translated by infectious disease news blog Avian Flu Diary, South Korea's government posted an announcement about seven more cases, which push the total to 25. All involve adults ages 39 to 78 who have nosocomial MERS-CoV infections.
One of the patients, a 57-year-old woman, died of her infection. The other death was reported in a previously reported case involving a 71-year-old man who got sick after sharing a hospital room with the index patient.
The government's announcement today of the most recent cases was also picked up by Yonhap News, which noted that the new cases include the first two tertiary (third-generation) illnesses.
According to WHO statements from May 30, May 31, and today, many of the patients have been transferred to South Korea's nationally designated medical center. Of the 14 patients covered in the three WHO statements, current status is noted for 7, who are all listed in stable condition. A media report today, though, said 5 of the patients are either on ventilators or are experiencing organ failure.
The illness onset for the index patient was May 11, and onsets noted for 12 of 13 others in the WHO reports range from May 18 to May 26. The WHO reports flesh out exposures for all of the cases that South Korea had reported as of May 30.
The WHO report today describes MERS-CoV in a 35-year-old man who was being treated for a possible TB infection and suggests possible exposures involving at least two other hospitals.
The agency said that, on May 20 after he was discharged from the hospital where he shared a ward with the index patient, he visited two different hospitals for a fever and was placed on antibiotics. After his symptoms persisted despite treatment he was admitted to a hospital on May 27, where his MERS-CoV infection was detected 2 days later.
Response and repercussions
The outbreak has triggered a massive contact tracing effort, along with sharp criticism within South Korea about how the country has handled the outbreak, according to media reports.
South Korean health officials are monitoring 682 possible contacts, up sharply from 64 on the list just a few days ago, the Korea Herald reported today. People on contact lists have been barred from leaving the country, an action officials took in the wake of the business traveler who left on a trip for China May 26 against medical recommendations. The man—a contact of one of the first cases—became China's first imported case a few days later.
The hospital where most of the patients were infected has been temporarily shuttered, and government officials and political leaders are in emergency talks on how to slow the spread of the disease, according to the Herald.
Yesterday, South Korea's health minister, Moon Hyung-Pyo, PhD, apologized at a media briefing for failing to curb the outbreak, Agence France-Presse (AFP) reported today. He added that this week would be a critical period for containing the disease.
After the first flurry of illnesses occurred after the index case was identified, officials admitted that some patients weren't on contact lists, and authorities have faced criticism for not having stronger measures in place to prevent people on contact lists from flying. The business traveler was considered a high-risk contact.
Moon said the hospital where the index case was detected and subsequent infections were found is closed and all patients are being treated in isolation, according to the report. He refused to name the facility, due to fear of spreading panic.
So far no other additional illnesses have been reported in Hong Kong, where the man stopped during his travel, or in mainland China. The WHO said in a May 30 statement that the man is the son of South Korea's third MERS-CoV case-patient and the younger brother of its fourth patient. The agency added that, after the man arrived at his final destination in Guangdong province, local health officials located him on May 27 and transferred him to a designated isolation facility.
Chinese health officials have 77 people in Guangdong province listed as close contacts of the South Korean man, whose illness was detected in Huizhou, China Daily reported today. So far 64 of them have been quarantined, but 13 others, including 11 passengers who rode a bus to Huizhou with the man, have not been found.
Meanwhile, Hong Kong authorities have quarantined 18 people at a resort in a remote part of the city for 2 weeks. They were seated on a plane within two rows of the man, the Associated Press (AP) reported yesterday. The story said another 17 people are being monitored.
ECDC updates risk assessment
In a May 30 epidemiologic update that covered South Korea's first 11 MERS cases, China's imported case, and the latest developments in the Middle East, the European Centre for Disease Prevention and Control (ECDC) said MERS-CoV importation to another nation isn't unexpected. The agency said that, when it occurred in France and the United Kingdom, it resulted in secondary transmission among patients and healthcare workers, as well as close relatives.
The ECDC acknowledged, however, that clusters of the size that South Korea is experiencing haven't been seen so far outside of the Arabian Peninsula. It added that the WHO has said there are currently no signs that the virus is behaving differently and that so far there is no sustained person-to-person transmission. "It is the first time that an imported case results in a secondary transmission affecting another country," the ECDC said.
Though it said the threat to Europe remains low, the risk of more imported cases is still a concern, making international surveillance for MERS-CoV crucial. The ECDC said secondary transmission to unprotected close contacts, including healthcare settings, as is occurring in South Korea, is still possible.
May 30 WHO statement on South Korea's first 11 cases
May 31 WHO statement on additional South Korean case
Jun 1 WHO statement on two South Korean cases
Jun 1 Avian Flu Diary post
FluTrackers South Korea MERS-CoV case list
Jun 1 Korea Herald story
May 30 WHO statement on China's first MERS-CoV case
Jun 1 AFP story
Jun 1 China Daily story
May 31 AP story
May 30 ECDC epidemiologic update
May 29 CIDRAP News story "China has first MERS case as Korean cluster grows"