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Why the panic? South Korea’s MERS response questioned

BMJ 2015; 350 doi: (Published 24 June 2015) Cite this as: BMJ 2015;350:h3403

Re: Why the panic? South Korea’s MERS response questioned

Since the first case of laboratory-confirmed Middle East Respiratory Syndrome coronavirus (MERS-CoV) in South Korea was reported on May 20, 2015, a total of 150 cases has been infected, including 18 deaths, according to the World Health Organization (WHO) as of June 16, 2015.[1] The current outbreak in the Far East Asia – mainly South Korea (149 patients) and China (1 patient coming from South Korea) – has grown to be the second largest MERS outbreak, after Saudi Arabia. Contrary to the global concern, the preliminary analysis of the viruses isolated from Korean patients turned out to have only minor mutations compared with Middle Eastern strains.[2] Alongside with negative test results of the few camels in zoological gardens within the country, challenges to curb the disease epidemic are now mainly focused on human-to-human transmission. So far, the vast majority of confirmed cases are linked to health-care facilities. With these measures, contact monitoring of all confirmed and suspected cases took place, putting a total of 5,216 people under quarantine within 26 days.1

The South Korean outbreak shows several similarities with the previous largest epidemic that happened in Saudi Arabia in 2014.[3 4] Similar to that of Riyadh and Jeddah, the current outbreak is also a cluster of hospital-associated transmissions, with over 95% of patients having clear routes sprouting from the initial infection (Appendix). Additionally, a remarkable proportion consisted of health care workers (17% in South Korea1 and 27% in Saudi Arabia[4]) (Table), and fatal patients more frequently had underlying chronic diseases.[5]

On the other hand, several factors may have contributed to the unexpectedly rapid spread of the MERS-CoV in South Korea. First, the low index of suspicion caused a delay in the initial diagnosis. The Korean government as well as the medical society had never experienced any cases of MERS before. The initial case, a 68-year-old male presented with non-specific symptoms such as high fever and cough starting on May 11. He went unrecognized for more than a week before finally being diagnosed on May 20 at the 4th hospital he visited.[6] During this period, huge gaps in national contact precaution occurred one after another, permitting the disease to rapidly spread around.

Second, the accessibility and affordability of health care in South Korea played a role in disease prevalence. During the 9 days before diagnosis, the initial patient visited 4 different healthcare facilities during 7 appointments. This so-called ‘Doctor Shopping’ – a well-known South Korean tendency of hopping hospitals for second opinions – is suspected to have encouraged virus transmission. Since the National Health Insurance Act on 1989, more than 96% of the general populations are covered by National Health Insurance Program (NHIP) with relatively low healthcare fees and high rates of reimbursement. Subsequently, the rate of annual outpatient department visitation was increased up to 14.6 per individual – The highest among countries of the Organization for Economic Cooperation and Development (OECD) – and the annual rate of hospital admission was increased to 16.1 per 100 individuals (4.5 and 10.5 in Saudi Arabia, respectively).[7 8]

Finally, a critical point in the current outbreak was several “super-spreaders” among the secondary cases. Notably, a 38-year-old male (Indicated 14th patient in Appendix) led to a striking number of tertiary infections, which caused the emergency department to account for a considerable part of the total transmissions (49% in South Korea1 and 8% in Saudi Arabia[4]). Although a 2-step health referral system exists, South Korean patients tend to seek large tertiary hospitals due to a common belief that the large, overcrowded hospitals provide better care. Due to shortage of available beds, the aforesaid 14th patient waited for three days in one of the largest hospital’s congested emergency room where more than 1,800 admitted patients with 8,500 outpatients pass each day.[9] Consequently, more than 70 tertiary infections out sprouted from these 3 days.

Far East Asian nations raised their alerts and exerted tighter arrival regulations from countries at risk of MERS. Although the initial bungled act of the Korean government and lack of coordination between the authorities and health care facilities amplified public anxiety, the Korean government are now coming forward openly with the full lists of affected hospitals and are making every effort to properly screen people at risk and assorting them for quarantine. The outbreak in South Korea appears to be undergoing a similar pattern as the previous outbreak in Saudi Arabia. As other Far East Asian nations such as China, Thailand or Japan share similar cultural backgrounds, health-related behaviors, and government policies, distinct features of the Korean outbreak may be noteworthy. In the future, a carefully planned and well-managed national response system, along with timely professional assistance will be an important task for Korea and the international medical society to accomplish before the next infectious disease crisis emerges.

1. World Health Organization. Western Pacific Region Outbreaks and Emergencies. June 16, 2015. ((accessed June 16, 2015).). Secondary World Health Organization. Western Pacific Region Outbreaks and Emergencies. June 16, 2015. ((accessed June 16, 2015).).
2. World Health Organization. Global Alert and Response. June 15, 2015. ((accessed June 17, 2015).).
3. World Health Organization. Global Alert and Response. June 11, 2014. ((accessed Jun 16, 2015).).
4. Assiri A, McGeer A, Perl TM, et al. Hospital outbreak of Middle East respiratory syndrome coronavirus. The New England journal of medicine 2013;369(5):407-16 doi: 10.1056/NEJMoa1306742[published Online First: Epub Date]|.
5. Zumla A, Hui DS, Perlman S. Middle East respiratory syndrome. Lancet 2015 doi: 10.1016/S0140-6736(15)60454-8[published Online First: Epub Date]|.
6. Su S, Wong G, Liu Y, et al. MERS in South Korea and China: a potential outbreak threat? Lancet 2015;385(9985):2349-50
7. Organization for Economic Cooperation and Development.; 2013. ((accessed June 17, 2015).).
8. Ministry of Health. Kingdom of Saudi Arabia. 2013. ((accessed June 17, 2015).). 2013
9. Korea Centers for Disease Control and Prevention.; June 16, 2015. ((accessed June 17, 2015).).

Competing interests: No competing interests

02 July 2015
Myung Han Hyun
Medical Doctor
Yoonjee Park
Department of Internal Medicine, Korea University Medical Center
Korea University Guro Hospital, Korea University Medical Center, 148 Gurodong-ro, Guro-gu, Seoul 152-703, Korea