# 7968
Last night on twitter World Health Organization spokesperson Gregory Hartl described it as `What we know, what we don’t know. Most comprehensive paper yet . . ‘ on the MERS coronavirus. And that’s a good assessment, as the 30 page PDF put together by the WHO MERS Research Group does a good job of laying out of what we’ve learned regarding this emerging coronavirus (through Oct 22nd, 2013), and provides an excellent reference.
While much has been learned over the past year, there remain notable gaps in our understanding of this virus, including:
- how the virus is spilling over into the human population?
- from what animal source did it emerge?
- How many people have really been infected?
- What role do mild, or asymptomatic cases play in the transmission of the virus?
- What is the most effective treatment for this infection?
- Is the virus spreading outside of the Middle East?
Although I’ve excerpted the Abstract, I would urge everyone download, and read this paper. Then keep it handy as a reference going forward. It is available online, or as a downloadable PDF, at the link below:
November 12, 2013 · Research
Abstract
Background: Between September 2012 and 22 October 2013, 144 laboratory-confirmed and 17 probable MERS-CoV cases from nine countries were notified to WHO.
Methods: We summarize what is known about the epidemiology, virology, phylogeny and emergence of MERS-CoV to inform public health policies.
Results: The median age of patients (n=161) was 50 years (range 14 months to 94 years), 64.5% were male and 63.4% experienced severe respiratory disease. 76.0% of patients were reported to have ≥1 underlying medical condition and fatal cases, compared to recovered or asymptomatic cases were more likely to have an underlying condition (86.8% vs. 42.4%, p<0.001). Analysis of genetic sequence data suggests multiple independent introductions into human populations and modelled estimates using epidemiologic and genetic data suggest R0 is <1, though the upper range of estimates may exceed 1. Index/sporadic cases (cases with no epidemiologic-link to other cases) were more likely to be older (median 59.0 years vs. 43.0 years, p<0.001) compared to secondary cases, although these proportions have declined over time. 80.9% vs. 67.2% of index/sporadic and secondary cases, respectively, reported ≥1 underlying condition. Clinical presentation ranges from asymptomatic to severe pneumonia with acute respiratory distress syndrome and multi-organ failure. Nearly all symptomatic patients presented with respiratory symptoms and 1/3 of patients also had gastrointestinal symptoms.
Conclusions: Sustained human-to-human transmission of MERS-CoV has not been observed. Outbreaks have been extinguished without overly aggressive isolation and quarantine suggesting that transmission of virus may be stopped with implementation of appropriate infection control measures.
