Middle East respiratory syndrome coronavirus (MERS-CoV) infection
Middle East respiratory syndrome coronavirus (MERS-CoV) infection is an uncommon coronavirus infection (<1000 cases) with the first case reported in Saudi Arabia in 2012. It most commonly causes pneumonia and acute renal failure with a mortality rate of ~40%. MERS-CoV raises concern because of its similarity to SARS-CoV infection, with similar spread via infected cases who travel by air.
MERS-CoV primary cases have been isolated to the Middle East (most commonly Saudi Arabia), travel-related cases have been reported in western Europe, North America and eastern Asia . The average age is ~50 years with a slight male predominance of 1.5:1 .
The infection may be subclinical. If symptomatic, features range from mild upper respiratory tract coryzal symptoms (high fever, cough) to severe respiratory distress and multiorgan failure . Vomiting and diarrhea are also a feature .
MERS-CoV belongs to lineage C of the β-coronaviruses, the first known to infect humans, and is a single-stranded RNA virus . The origin and mode of transmission are unclear, but bats are the likely original source and transmission suspected to be via dromedary camels . Human-to-human transmission occurs and is responsible for the international spread .
MERS-CoV infection can result in:
The radiographic features of MERS-CoV infection can be variable due to the variability in the severity of disease .
Reported chest x-ray features in a case series of 55 patients :
- peripheral ground-glass opacity (65%)
- consolidation (20%)
- pneumothoraces, pleural effusions, and progressive involvement of all lungs zones are associated with higher mortality
Reported CT chest features in a case series of seven patients :