Middle East Respiratory Syndrome (MERS) coronavirus threatened emergence in the United States in May 2014, when two healthcare workers became symptomatic after working in Saudi Arabian hospitals.

The emerging infection was identified and stopped, but healthcare workers in Saudi Arabia and the surrounding region still are acquiring MERS — sometimes fatally.

A recently published analysis1 of reported MERS cases between December 2016 and January 2019 revealed that 26% of 403 cases in the region were healthcare workers. The case fatality rate was a disturbing 16% among healthcare workers, compared to 34% among patients. Only 1.9% of the healthcare workers infected had comorbidities compared to 71% in other MERS cases over the period.

“Healthcare workers constitute a high-risk group owing to continued exposure at healthcare settings,” the authors warned. “It is important to screen exposed healthcare workers prior to allowing them to resume medical duties, and multiple samples may be needed. In addition, there is a need for continued vigilance and identification of suspected cases.”

Early Detection, Treatment Vital

The review period included a large outbreak in Saudi Arabia in 2017 involving three hospitals, with healthcare workers acquiring the virus from admitted patients. “All healthcare facilities should adopt strategies for early detection and isolation of patients suspected to have MERS infection,” the authors reported.

Most healthcare workers who acquire MERS experience mild or asymptomatic infections. However, there have been cases of asymptomatic workers transmitting MERS to their colleagues.

In addition to Saudi Arabia, MERS cases were reported from Lebanon, Malaysia, Oman, Qatar, and United Arab Emirates. Although most likely of bat origin, the coronavirus has established an animal reservoir in camels in the region. Camel exposures, primarily consuming camel milk, were reported in 64% of the community MERS cases.

The first MERS cases emerged in 2012, and the link to dromedary camels now is well established. The camel is deeply entrenched the Saudi culture, which has thus far resisted the kind of large cull of animal reservoirs performed for emerging infections like SARS and H5N1 avian flu.


1. Al-Tawfiq, Memish ZA. Middle East respiratory syndrome coronavirus in the last two years: Health care workers still at risk. American Jrl Infect Control 2019;47:1167-1170.