The number of cases in South Korea's hospital-linked MERS-CoV outbreak more than doubled over the weekend and into today, with 87 infections reported so far, with many of the newest cases representing third-tier illnesses detected at additional hospitals.
South Korea reported 9 new cases of MERS-CoV (Middle East respiratory syndrome coronavirus) on Saturday, 14 on Sunday, and 23 new cases today, according to official sources and media reports. Though the number of tertiary cases is growing quickly and is concerning to health officials, they say there is still no sign of sustained human-to-human transmission in the community, which would signal a much more serious disease threat.
Also, two more deaths were reported, lifting the fatality count to six, as South Korea's health ministry revealed the names of 6 hospitals were multiple cases have been reported, along with 18 other facilities that had some type of contact with a MERS patient.
Details on the 46 new cases
The 9 MERS-CoV cases reported on Jun 6 included 5 from Samsung Medical Center in Seoul, where an infection in a doctor was recently found, Yonhap News Agency reported.
Three other infections were in patients and staff at St Mary's Hospital in Pyeongtaek, a facility about 40 miles south of Seoul where the outbreak's index patient was treated. His infection in mid-May led to the first round of illnesses among his hospital roommates, family members, those who were on the same ward, and healthcare workers. Some of the patients who were infected at St Mary's were admitted to other hospitals, a situation that led to other illnesses.
Fourteen cases reported on Jun 7 included a 75-year-old man whose MERS-CoV infection was found only after he died, according to a separate Yonhap News story. Ten of the patients are people who were exposed to the virus while they were in the emergency department of Seoul's Samsung Hospital. The other 4 got sick after close contact with MERS patients at other hospitals.
Samsung Hospital said it has isolated about 900 patients and staff who may have had contact with a MERS-CoV case-patient who was in the emergency department at the end of May.
The 87 total cases puts South Korea ahead of the United Arab Emirates, which has 74 MERS-CoV cases, so Korea is now the second-hardest-hit country, behind Saudi Arabia, which has confirmed 1,027 (see related story today).
The latest Korean cases include 17 who were infected at Samsung Medical Center, Yonhap News reported today, citing the country's health ministry. Six others were infected while visiting two other hospitals, according to the report.
In other developments, South Korea had its first MERS-CoV infection in a teenager, involving a 16-year-old boy who was diagnosed at Samsung Medical Center, where he had been hospitalized since May 27 for a different condition, Yonhap reported today. Also, the health ministry today announced the sixth death from the disease, in an 80-year-old patient who died while being treated at a hospital in Daejeon.
Officials name 24 hospitals
As of yesterday there were 2,300 people in isolation at state-designated hospitals or in their homes, according to Yonhap.
Government officials yesterday revealed the names of all hospitals affected by the MERS-CoV outbreak. In addition to St. Mary's and Samsung, the four other hospitals where the disease has been diagnosed are the 365 Open Clinic in Seoul; Asan Seoul Clinic in Asan, South Chungcheong province; Dae Cheong Hospital in Daejeong; and Konyang University Hospital in Daejeon, the Korea Observer reported.
Eighteen other hospitals had MERS-CoV patients in their facilities at some point, according to the report. Five are in Seoul, five are in Pyeongtaek, five are in other Gyeonggi province locations, two are in South Chungcheong Province, and one is in North Jeolla Province.
WHO details 14 earlier cases
The World Health Organization (WHO), meanwhile, in two separate statements shared more details on 14 earlier cases reported by South Korea on Jun 5 and Jun 6.
Of the 14 patients profiled in the two statements, 6 are women and 8 are men, with ages ranging from 24 to 81. Their illness-onset dates ranged from May 22 to Jun 4, but onset dates are not listed for 2 of the patients.
The WHO does not list the condition of any of the patients. The Jun 6 statement notes the death of one previously reported patient, whose case was noted in a May 30 WHO update.
At least 12 of the 14 patients had exposure to MERS-CoV in a hospital before they got sick, mostly by being in a zone, ward, or room where other MERS patients were being treated or had been treated, the WHO updates show. The hospitals are not identified.
Of the other two patients, one is a 24-year-old man who got sick on May 22 and then was hospitalized from May 22 to 28 in a room where two previous MERS patients had been treated. The other patient, who fell ill on May 31, is a 70-year-old woman whose husband was cared for by a doctor who tested positive for MERS-CoV on Jun 3. The WHO did not specify whether the woman had any in-hospital exposure to the virus before she got sick.
One patient covered in the Jun 8 statement, a 54-year-old woman, was hospitalized May 19 and 20 in the same ward where the first patient in the outbreak had been treated. She was then transferred to another floor where several other MERS patients were treated.
Genetic sequences
The first analysis of genetic sequences from South Korean patient samples suggests that the virus is very similar to those isolated from patients in Saudi Arabia, according to a Jun 6 statement from South Korea's Health and Human Services translated and posted by Avian Flu Diary, an infectious disease news message board.
The statement notes that the South Korean MERS-CoV gene sequence is 99.55% similar to a 2013 isolate from Saudi Arabia. It also suggested that other groups are analyzing the South Korean virus, including the country's virus society, the US Centers for Disease Control and Prevention, and Erasmus Medical Center in the Netherlands.
Christian Drosten, MD, a virologist at the University of Bonn, on Jun 6 commented on Twitter that the South Korea virus phylogeny matches travel to Qatar, but added that MERS-CoV exists in camels across the northeastern Arab peninsula. He also noted that the closest relatives to the Korean MERS-CoV virus are from Riyadh, Hafr Al-Batin, Medina, and Qatar, most of them collected in 2013.
The index patient had traveled to Bahrain, the UAE, Saudi Arabia, and Qatar before he got sick. The WHO has said it is in contact with health authorities in Middle Eastern countries to determine how the man was exposed to the virus. A Jun 5 risk assessment from the European Centre for Disease Prevention and Control said the man didn't have documented contact with camels or healthcare settings during his recent visits to those countries.
WHO joint mission
In another development, South Korea's government shared more details today about a joint mission with the WHO to probe the MERS outbreak. In an English-language statement, it said the mission will be conducted from Jun 9 through Jun 13 and will be led by Jong-Koo Lee, MD, PhD, MPH, who directs the JW Lee Center for Global Medicine at Seoul National University College of Medicine and Keiji Fukuda, MD, the WHO's assistant director-general for health security.
Eight South Korean experts and eight of their international colleagues will discuss the epidemiologic investigations into the cases and infection control practices, visit hospitals that have had confirmed cases, and analyze virus characteristics.
The group is slated to present its findings to South Korea's health ministry on Jun 13, with a press conference to follow the same day.
News editor Robert Roos contributed to this story.
See also:
Jun 6 Yonhap News story on 9 Saturday cases
Jun 7 Yonhap News story on 14 Sunday cases
Jun 8 Yonhap News story on 23 cases today
Jun 8 Yonhap News story on infected teen
FluTrackers South Korea MERS-CoV case list
Jun 7 Korea Observer story
Jun 6 Avian Flu Diary post
Christian Drosten Twitter stream
Jun 8 Korean government statement on WHO joint mission
Jun 6 WHO statement on 5 MERS cases from Jun 5
Jun 8 WHO statement on 9 MERS cases from Jun 6
