Fatality risks for nosocomial outbreaks of Middle East respiratory syndrome coronavirus in the Middle East and South Korea

Abstract

Middle East respiratory syndrome coronavirus (MERS-CoV) was first isolated in 2012. The largest known outbreak outside the Middle East occurred in South Korea in 2015. As of 29 June 2016, 1769 laboratory-confirmed cases (630 deaths; 35.6 % case fatality rate [CFR]) had been reported from 26 countries, particularly in the Middle East. However, the CFR for hospital outbreaks was higher than that of family clusters in the Middle East and Korea. Here, we compared the mortality rates for 51 nosocomial outbreaks in the Middle East and one outbreak of MERS-CoV in South Korea. Our findings showed the CFR in the Middle East was much higher than that in South Korea (25.9 % [56/216] vs. 13.8 % [24/174], p = 0.003). Infected individuals who died were, on average, older than those who survived in both the Middle East (64 years [25-98] vs. 46 years [2-85], p = 0.000) and South Korea (68 years [49-82] vs. 53.5 years [16-87], p = 0.000). Similarly, the co-morbidity rates for the fatal cases were statistically higher than for the nonfatal cases in both the Middle East (64.3 % [36/56] vs. 28.1 % [45/160], p = 0.000) and South Korea (45.8 % [11/24] vs. 12.0 % [18/150], p = 0.000). The median number of days from onset to confirmation of infection in the fatal cases was longer than that for survivors from the Middle East (8 days [1-47] vs. 4 days [0-14], p = 0.009). Thus, older age, pre-existing concurrent diseases, and delayed confirmation increase the odds of a fatal outcome in nosocomial MERS-CoV outbreaks in the Middle East and South Korea.

MERS transmission and risk factors: a systematic review

“… n.r. • Contacts - 20 primary, 39 first, 18 s, 7 third, 3 fourth generation • Secondary attack rate/10,000: 42 (95% CI: 33–54) Kim (2017) South Korea 2015 186 (111/75) 55 38/186 (19.9%) • Contacts - Hospital (99.4%) - Household (0.6%) - Community (0%) • Comorbidity - 29/38 fatalities had underlying disease Park (2017) [ 23 ] South Korea 2015 25 (13/12) 71 a (IQR: 38–86) 25/11 (44.0%) • Attack rate: 3.7% • Incubation period: 6.1 days Sha (2017) [ 29 ] Middle East area/ South Korea 2012–2016 683 (423/260) 50–60 (fatal), 38–46 (non-fatal) 182 (26.6%) (Middle East: 25.9%, South Korea: 13.8%) • Comorbidity - 67.9% in fatal, 22.2% in nonfatal cases • Incubation period - 4.5–5 days in Middle East area - 6 days in South Korea • Onset to confirmation - 8 days in fatal, 4 days in nonfatal in Middle East area - 4 days in fatal, 5 days nonfatal in South Korea • Onset to death - 11.5 days in Middle East area - 11 days in South Korea • Onset to discharge - 14 days in Middle East area - 17 days in South Korea Sherbini (2017) [ 32 ] Saudi Arabia 2014 29 (20/9) 45 ± 12 10 (34%) • Comorbidities - Diabetes (31%) - Chronic kidney disease (27%) • Symptoms to hospitalization: 2.9–5 days Assiri (2016) [ 36 ] Saudi Arabia 2014–2015 38 (28/10) 51 (range 17–84) 21/38 (55.3%) • Contacts - 13 HCWs - 15 were associated with 1 dialysis unit • Onset to death/discharge: 17 days (range 1.0–84.0) Cho (2016) [ 5 ] South Korea 2015 82 (53/29) 57 (patients and visitors), 38 (HCW) n.r. • Contacts - Patients: 40.2% - Visito...…”

“…One study using data from Saudi Arabia reported a 5.2 day incubation period [ 7 ], and another using data from multiple areas reported a 5.5 day incubation period [ 6 ]. Sha et al compared the incubation periods between the Middle East area and South Korea and reported 4.5–5 and 6 days, respectively [ 29 ].…”

Middle East respiratory syndrome

“…Several studies have reported disease severity and mortality risk factor data from patients in the Middle East and South Korea. 11,12,21,[114][115][116][117] Ahmed and colleagues collected the daily information on MERS-CoV cases posted online by the Saudi Arabian Ministry of Health between Dec 2, 2014, and Nov 12, 2016, and reviewed 660 laboratory-confirmed cases of MERS. 114 They showed mortality at day 3 (13·8%), day 30 (28·3%), and overall (29·8%).…”

Epidemiological factors and worldwide pattern of Middle East respiratory syndrome coronavirus from 2013 to 2016

“…However, the health ministry of Saudi Arabia recommends pilgrims over 65 years; those with chronic diseases, such as heart, kidney, and respiratory diseases, diabetes, and immune deficiency; pregnant women; and children under 12 years, who are planning to attend the Hajj, to postpone their visit. 4 , 5 …”