Case characteristics among Middle East respiratory syndrome coronavirus outbreak and non-outbreak cases in Saudi Arabia from 2012 to 2015

Alhamlan, F S; Majumder, M S; Brownstein, J S; Hawkins, J; Al-Abdely, H M; Alzahrani, A; Obaid, D A; Al-Ahdal, M N; BinSaeed, A

Arabian Peninsula, with no evidence of MERS-CoV infection detected in cows, goats or sheep. 7-10 One study isolated the full MERS-CoV genome sequences from a dromedary camel and from a patient who died of laboratory-confirmed MERS-CoV infection after close contact with camels; the two isolates were identical. According to serological data, MERS-CoV had been circulating in the camel-but not in the patient-before human infection occurred, suggesting that MERS-CoV had been transmitted to the patient via the infected camel. 11 Whether MERS-CoV is new to camel or human populations or whether it has been present but undetected for years remains unknown. Nonetheless, MERS-CoV was initially regarded primarily as a zoonotic pathogen, with only limited documentation of person-to-person transmission. However, MERS outbreaks of varying proportions have since occurred across Saudi Arabia; additionally, apparent cases of sustained secondary transmission have occurred in family clusters 12 13 and healthcare facilities. 14 15 Much remains unknown about MERS, including the risk factors associated with MERS-CoV transmissions in outbreak and non-outbreak settings. Here, we aimed to increase our understanding of the spread and mode of transmission of MERS-CoV by comparing the epidemiological, demographic and clinical characteristics of outbreak and non-outbreak MERS-CoV infections from September 2012 to October 2015 as reported to the Saudi Arabian Ministry of Health (MOH).