Based off of the latest numbers, 29% of all MERS cases diagnosed since the onset of the current outbreak in the Middle East have been healthcare workers (HCW):
This may – at least in part – be due to increased surveillance; however, healthcare workers are also more vulnerable to contracting the virus during an outbreak situation simply due to their occupation.
Thankfully, 97% of these 64 cases have been non-fatal; in fact, nearly half of them have been asymptomatic:
Healthcare workers may remain asymptomatic after infection for several reasons. One of the most compelling is rooted in the rate of comorbidity in this particular population. Healthcare workers during this outbreak have had fewer comorbidities – such as diabetes, heart disease, etc. – than their general public (GP) counterparts:
Given that comorbidity correlates with increased likelihood of death due to MERS, it’s possible that good systemic health actively prevents symptoms from ever appearing in those infected with MERS-CoV. [This theory may gain credibility as scientists continue to investigate the impact of the virus on the body’s many systems.]
However, just because an individual is asymptomatic doesn’t mean he or she isn’t spreading the virus. Assuming that transmission is possible, this distinct lack of pathology is what makes healthcare workers an ideal vector for the disease – especially in hospital settings. Because they feel normal, they go about their business as they usually would – potentially exposing their patients in the process.
While members of the healthcare population seem to be somewhat protected from manifesting severe disease pathology, the patients that they take care of are often immunocompromised. If comorbidity really does impact disease severity as much as it seems, asymptomatic healthcare workers may be facilitating death-by-MERS without even knowing it.
The message is clear: infection prevention among healthcare workers is critical to the health of the general public… And it may also prove essential to curbing the outbreak at large. After all, healthcare workers need to be healthy to properly do their jobs. [And that means free of MERS-CoV, symptomatic or not.]
Note: Temporal data indicates date of onset, hospitalization, diagnosis, or public reporting.
Data Sources: KSA MoH & WHO