SuperbugsNovel Coronavirus in China's Outbreak

Published 9 January 2020

As suspected, a novel coronavirus has been identified in some patients who are part of a cluster of unexplained pneumonia cases in Wuhan, China. Experts say that the identification of what now appears to be a third novel coronavirus that can cause serious human disease in the last 20 years signals a paradigm shift for coronaviruses.

As suspected, a novel coronavirus has been identified in some patients who are part of a cluster of unexplained pneumonia cases in Wuhan, China, according to unnamed sources familiar with the investigation who are cited in a Wall Street Journal (WSJ) story Wednesday.

As scientists and health officials wait for official statements and more confirmation details, some virologists say they are not surprised to see another human emergence of coronavirus, a group of species that is becoming a bigger player on the world stage. The new discovery comes in the wake of the SARS (severe acute respiratory syndrome) outbreak in 2003 and the first human detection of MERS-CoV (Middle East respiratory syndrome coronavirus) in 2012.

A WSJ source said the novel strain has been genetically sequenced from one patient sample and was found in some of the others, but it hasn’t been confirmed as the underlying cause in all of the 59 outbreak cases.

Six Coronaviruses Tied to Human Cases
Tim Sheahan, Ph.D., a coronavirus expert who is an assistant professor in the department of epidemiology at the University of North Carolina at Chapel Hill Gillings School of Global Public Health, said there are six coronavirus known to infect humans. Four of them typically cause common cold symptoms. The other two— SARS and MERS-CoV—have been linked to sometimes fatal illnesses.

CIDRAP reports that as is the case with SARS and MERS-CoV, the newly detected coronavirus probably has a zoonotic source, he said, noting that intensive epidemiological investigations are likely under way in China to trace the virus reservoir.

The seafood market at the center of the investigation also sold live animals such as poultry, bats, marmots, and snakes. In the SARS outbreak, bats harbored the virus, which passed it to palm civets as the intermediate host, which then transmitted the virus to people in the live-market setting.

Before SARS emerged, coronaviruses were typically known as nuisance viruses in agriculture and pets, but over the last two decades they have become game changers, given that some of the newly identified ones can cause severe disease, Sheahan said.

Questions Persist about Patient Profile
Virologists say what’s known so far about the patients’ clinical picture fits with coronavirus infection, but they want to know more about the profiles of patients who are getting sick, such as their ages and if they have underlying health conditions.