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

• Type of Material: Article
• Authors: David S. Hui, Chinese University of Hong Kong; Esam I. Azhar, King Abdulaziz University; Yae-Jean Kim, Sungkyunkwan University; Ziad Memish, Emory University; Myoung-don Oh, Seoul National University; Alimuddin Zumla, University College London
• Language: English
• Date: 2018-08-01
• Publisher: Elsevier
• Publication Version: Final Published Version
• Copyright Statement: © 2018 Elsevier Ltd. All rights reserved.
• Final Published Version (URL): http://dx.doi.org/10.1016/S1473-3099(18)30127-0
• Title of Journal or Parent Work: The Lancet Infectious Diseases
• Volume: 18
• Issue: 8
• Start Page: e217
• End Page: e227
• Grant/Funding Information: AZ acknowledges support from the National Institute of Health and Research (NIHR) Biomedical Research Centre at University College London Hospitals (UK) and is in receipt of an NIHR Senior Investigator award.
• Keywords: Risk Factors; Family Characteristics; Coronavirus Infections; Middle East Respiratory Syndrome Coronavirus; Cross Infection; Saudi Arabia; Humans; Animals; Camelus; Zoonoses; Global Health; Disease Outbreaks; Disease Transmission, Infectious
• Research Categories: Health Sciences, Health Care Management; Health Sciences, Epidemiology; Health Sciences, Occupational Health and Safety; Health Sciences, Public Health

Abstract

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.