Middle East respiratory syndrome coronavirus: risk factors and determinants of primary, household, and nosocomial transmission

• Published in: The Lancet infectious diseases Vol. 18; no. 8; pp. e217 - e227
• Main Authors: Hui, David S, Azhar, Esam I, Kim, Yae-Jean, Memish, Ziad A, Oh, Myoung-don, Zumla, Alimuddin
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.08.2018; Elsevier B.V; Elsevier Limited
• Subjects: Animals; Asymptomatic; Camels; Camelus; Camelus dromedarius; Coronaviridae; Coronavirus Infections - diagnosis; Coronavirus Infections - epidemiology; Coronavirus Infections - mortality; Coronaviruses; Cross Infection; Diagnosis; Disease control; Disease Outbreaks; Disease prevention; Disease transmission; Disease Transmission, Infectious; Epidemics; Epidemiology; Family Characteristics; Fatalities; Global Health; Health aspects; Health care facilities; Health surveillance; Hospital facilities; Hospitals; Households; Humans; Immunoglobulins; Infections; Infectious diseases; Middle East Respiratory Syndrome Coronavirus - isolation & purification; Middle East Respiratory Syndrome Coronavirus - pathogenicity; Mortality; Nosocomial infection; Outbreaks; Public health; Respiratory diseases; Respiratory tract; Respiratory tract diseases; Risk analysis; Risk Factors; Saudi Arabia - epidemiology; Viruses; Zoonoses; Saudi Arabia; Middle East; Arabian Peninsula; South Korea; United Kingdom > UK; United States > US; Qatar; Egypt; United Arab Emirates; Bahrain
• ISSN: 1473-3099; 1474-4457; 1474-4457
• DOI: 10.1016/S1473-3099(18)30127-0

Middle East respiratory syndrome coronavirus (MERS-CoV) is a lethal zoonosis that causes death in 35·7% of cases. As of Feb 28, 2018, 2182 cases of MERS-CoV infection (with 779 deaths) in 27 countries were reported to WHO worldwide, with most being reported in Saudi Arabia (1807 cases with 705 deaths). MERS-CoV features prominently in the WHO blueprint list of priority pathogens that threaten global health security. Although primary transmission of MERS-CoV to human beings is linked to exposure to dromedary camels (Camelus dromedarius), the exact mode by which MERS-CoV infection is acquired remains undefined. Up to 50% of MERS-CoV cases in Saudi Arabia have been classified as secondary, occurring from human-to-human transmission through contact with asymptomatic or symptomatic individuals infected with MERS-CoV. Hospital outbreaks of MERS-CoV are a hallmark of MERS-CoV infection. The clinical features associated with MERS-CoV infection are not MERS-specific and are similar to other respiratory tract infections. Thus, the diagnosis of MERS can easily be missed, unless the doctor or health-care worker has a high degree of clinical awareness and the patient undergoes specific testing for MERS-CoV. The largest outbreak of MERS-CoV outside the Arabian Peninsula occurred in South Korea in May, 2015, resulting in 186 cases with 38 deaths. This outbreak was caused by a traveller with undiagnosed MERS-CoV infection who became ill after returning to Seoul from a trip to the Middle East. The traveller visited several health facilities in South Korea, transmitting the virus to many other individuals long before a diagnosis was made. With 10 million pilgrims visiting Saudi Arabia each year from 182 countries, watchful surveillance by public health systems, and a high degree of clinical awareness of the possibility of MERS-CoV infection is essential. In this Review, we provide a comprehensive update and synthesis of the latest available data on the epidemiology, determinants, and risk factors of primary, household, and nosocomial transmission of MERS-CoV, and suggest measures to reduce risk of transmission.