From: MERS transmission and risk factors: a systematic review
Author (year) | Country | Study period | No. of patients (M/F) Age of patients | Fatality rate | Contact/ comorbidity | Index related to infectivity | Index related to severity |
Ahmed (2017) [31] | Saudi Arabia | 2015–2017 | 537 (370/167) 55 ± 17.9 | 218/537 (40.6%) | • Comorbidity: 73.9% • Contacts - Hospital-acquired: 38.7% - Household: 9.9% - Camel: 25.3% - Unknown: 26.1% | • Onset to confirmation: 4 days (IQR: 2–7 days) | |
Alenazi (2017) [12] | Saudi Arabia | 2015 | 130 (66/64) 63.5 (community-acquired), 64.7 (healthcare-acquired), 40.1 (HCW) | 51/130 (39.2%) | • Contacts - Community-acquired: 20% - Healthcare-acquired: 46.9% - HCWs: 33.1% | • R - Hospital-acquired: 0.98 for 2nd, 0.64 for 3rd, 0.23 for 4th generation | |
El- Bushra (2017) [21] | Saudi Arabia | 2015 | 87 n.r. | 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) 71a (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% - Visitors: 50% - HCWs: 9.8% • Comorbidity - 24 (29%) had underlying disease | • Incubation period: 7 days (range: 2–17, IQR: 5–10) • Overall attack rate - Patients in the emergency room: 4% (30/ 675) - Visitors: 6% (38/683) | |
Halim (2016) [33] | Saudi Arabia | 2016 | 32 (20/12) 43.99 ± 13.03 | 14/32 (43.8%) | • From symptom to hospitalization - 5.3 ± 3.3 days • Total length of stay - 15 ± 3.6 days | ||
Liu (2016) | Taiwan | 2012–2015 | 1368 (883/476)a 49 (range: 2–90) | 35.6% (487/1368) • CFR 7.03% for HCW - 36.96% for non-HCW | • Contacts - Patients: 46.2% - Family members or visitors: 34.9% - HCW: 18.9% | • Onset to death - 13 (4–17) days for HCP - 12 (1–52) days for non-HCW • Onset to confirmation - 6 (1–14) days for HCP - 10 (1–21) days for non-HCW | |
Mohd (2016) [40] | Saudi Arabia | 2014–2015 | 80 (48/32) 40a | • 10% (8/80) | • Comorbidity - Not different from non-MERS groups | ||
Park (2016) [24] | South Korea | 2015 | 23 (13/10) 66a (range: 31–87) in hospital A; 74.5a (range: 60–82) in hospital B | 11/23 (47.8%) | • Generation - 23 in 2nd; 3 in 3rd | • Incubation period - 7.8 days (95% CI: 6.0–10.0) • Serial interval - 14.6 days (95% CI, 12.9–16.5) • Secondary attack rate - 15.8% in hospital A - 14.3% in hospital B | • Time to deathc - 12.5 days (IQR: 5.5–19) in hospital A - 11 days (IQR: 9–16) in hospital B |
Virlogeux (2016) [25] | South Korea | 2015 | 170 (98/72) 54.6 ± 16.2 | 36/170 (21%) | Incubation period: 6.9 days (95% CI: 6.3–7.5) | ||
Chowell (2015) [8] | Saudi Arabia, South Korea | 2013–2015 | 973 MERS and 7634 SARS cases n.r. | n.r. | • Contacts - 43.5–100% were linked to healthcare setting in MERS | R0 (95% CI) - MERS: 0.91 (0.36–1.44) - SARS: 0.95 (0.67–1.23) Infection rate of disease among HCWs: - MERS: 13.4–13.5% - SARS: 18.8–57.1% | |
Cowling (2015) [26] | South Korea | 2015 | 166 (101/65) 55.4 (range: 16–87) | 24/166 (14.5%) | • Contacts - 119 cases had contact with a confirmed case - 30/166 (18%) were healthcare personnel | • Incubation period: 6.7 days • Serial interval: 12.6 days. | |
KCDC (2015) [4] | South Korea | 2015 | 186 (111/75) 55a (IQR: 42–66) | 36/186 (19.4%) | • Contacts - 44.1% patients exposed in hospitals - 32.8% caregivers - 13.4% HCWs • Comorbidities - 45.2% | • Incubation period - 6.83 days (95% CI: 6.31,7.36) | |
Ki (2015) [3] | South Korea | 2015 | 186 (111/75) 50s in men and 60s in women | 36/186 (19.4%) | • Generation - 28 in 1st (15.1%); 125 in 2nd (67.2%); 32 in 3rd (17.2%); 2 were not certain • Contacts - Same hospital: 82 (44%) - Family/healthcare aides/visitors: 71 (38%) - HCWs: 31 (17%) • Comorbidities - 77 (41%) had underlying diseases | • Incubation period: 6.5 days (2–16 days). | • From symptom onset to confirmation: 5 days (0–17 days) • From symptom onset to discharge from the hospital: 20 days (8–41 days). • From symptom onset to death: 13 days (1–41 days) |
Ministry of Health, South Korea (2016) [27] | South Korea | 2015 | 186 (111/75) 50s (21.6%), 60s (19.9%) | 38/186 (20.4%) | • Generation - 28 in 2nd, 120 in 3rd, 26 in 4th, 11 in unclear/ unknown • Contacts - 82 patients in hospital - 63 family members/ visitors - 39 HCWs - 2 others | • Incubation period - 6.83 days (95% CI: 6.31–7.36) | |
Noorwali (2015) [37] | Saudi Arabia | 2014 | 261 (171/90) n.r. | 110/261 (42%) | • Contacts - 84 HCWs - 177 non-HCWs | ||
Park (2015) [28] | South Korea | 2015 | 37 (21/16) 51.7 (range: 24–79) | 6/37 (16.2%) | • Generation - 1 in 1st, 25 in 2nd, 11 in 3rd • Contacts - 20 patients - 12 relatives of patients - 3 HCWs - 1 unrelated visitors • Comorbidities - 5/6 in fatal, 3/31 in nonfatal | Incubation period - 6 days (95% CI: 4–7 days) | • Symptom onset to confirmation - 6.5 days (95% CI: 4–9) for all cases - 9 days for second cases - 4 days for third cases |
Drosten (2014) [22] | Saudi Arabia | 2013 | 26 (17/9) 55a (range: 2–83) | 18/26 (69.2%) | • Contacts - 280 household contacts | • Secondary transmission: 4% | |
Assiri (2013) [7] | Saudi Arabia | 2012–2013 | 47 (36/11) n.r. | 28/47 (60%) | • Comorbidities - 45 had underlying comorbid medical disorders (96%) | • Incubation period: 5.2 days | |
Breban (2013) [9] | Multiple areas | 2012–2013 | 64 (44/17) b 56a (IQR 41–68.5) | 38/64 (59.4%) | n.r. | • R0: 0.69 (95% CI 0.50–0.92) | |
Oboho (2012) [38] | Saudi Arabia | 2014 | 255 (174/81) 45a (IQR:30–59) | 93 (36.5%) | • Contacts - 40 of 191 symptomatic were HCWs (20.9%) | n.r. | |
Penttinen (2013) [41] | Multiple areas | 2012–2013 | 133 (51/77) b n.r. | 45% | • Contacts - 14 primary cases, 129 cases on transmission | • Proportion to ICU: 60 cases (45%) | |
Estimating the index of infectivity and severity using secondary data | |||||||
Author (year) | Country | Study period | Indexes related to infectivity | Index related to severity | |||
Chang (2017) [18] | South Korea | 2015 | • R0 - 8.097 | ||||
Choi (2017) [15] | South Korea, Saudi Arabia | 2015 | • R0 - 3.9 in South Korea - 1.9–3.9 in Saudi Arabia (1.9 in Riyadh, 3.9 in Jeddah) | ||||
Eifan (2017) [13] | Saudi Arabia | 2013–2015 | • R - 0.85–0.97 | ||||
Zhang (2017) [17] | South Korea | 2015 | • R - 2.5–7.2 | ||||
Kim (2016) [16] | South Korea | 2015 | • R0 - 5.4 (95% CI: 4.61–6.19) in period 1 - 0.14 (95% CI: 0.04–0.26) in period 2 • Infectivity of hospitalized patients - 22 (95% CI: 18.73–25.27) in period 1 - 1 (95% CI: 0.16–1.84) in period 2 | ||||
Lessler (2016) [39] | Saudi Arabia | 2012–2014 | • CFR: 22% (95% CI: 18, 25) | ||||
Kucharski (2015) [10] | Multiple areas | 2012–2013 | • R0: 0.47 (95% CI: 0.29–0.80) | ||||
Mizumoto (2015) [35] | South Korea | 2015 | • CFR: 20.0% (95% CI): 14.6, 26.2). | ||||
Xia (2015) [19] | South Korea | 2015 | • R0 - 4.422 in early stage - 0.385 with control | from hospitalization to death: 15.16 (0–42) (mean, range) | |||
Cauche-mez (2014) [6] | Multiple areas | 2012–2013 | • Incubation period - 5.5 (95% CI: 3.6–10·2) • R0: 0.8–1.3 | • CFR - 74% (95% CI: 49–91) for first cases - 21% (95% CI: 7–42) for second cases | |||
Chowell (2014) [11] | Saudi Arabia | 2013 | • R overall - 0.45 (95% CI: 0.29, 0.61) under the surveillance-bias scenario - 0.88 (95% CI: 0.58, 1.20) under the differential-transmissibility scenario | ||||
Poletto (2014) [14] | Middle East area | 2012–2013 | • R: 0.50 (95% CI: 0.30–0.77) |