Experts highlight role of super-spreaders in outbr

Experts highlight role of super-spreaders in outbreaks

Super-spreading events have occurred with MERS-CoV and its predecessor SARS before it, as well as to a lesser extent with Ebola, according to a review article yesterday in Cell Host & Microbe that lists steps that might help reduce such events.

A Chinese team of experts noted that about 75% of the 186 MERS-CoV cases in South Korea can be traced to just three super-spreaders. With SARS (severe acute respiratory syndrome), another coronavirus disease, super-spreading events involved the index patient in Hong Kong (at least 125 secondary cases) and occurred at the the Hotel Metropole (13 cases) and the Amoy Gardens housing complex (more than 180 cases) in Hong Kong, as well as aboard an Air China flight traveling from Hong Kong to Beijing (22 cases).

The scientists say that super-spreaders also contributed to West Africa's Ebola outbreak, though to a lesser degree. They cite the example of a traditional healer who died in Sierra Leone and was shown to have directly infected 13 others and was eventually linked to more than 300 cases.

The authors say that a complex combination of factors—such as virus mutation, duration of contact with an infected person, genetic susceptibility, underlying medical conditions, air recirculation, travel and trade, and customs and beliefs—likely plays a role in super-spreading events.

They recommend animal studies to identify factors that likely contribute, as well as detailed analyses of the large amount of patient data and samples available from the recent Korean MERS-CoV and West Africa Ebola outbreaks.

http://www.cidrap.umn.edu/news-perspective/2015/10/news-scan-oct-15-2015