close
Tuesday April 16, 2024

About the virus

By Rob Wallace
February 25, 2020

A new deadly coronavirus 2019-nCoV, related to SARS and MERS and apparently originating in live animal markets in Wuhan, China, is starting to spread worldwide.

Chinese authorities have reported 5974 cases nationwide, 1000 of them severe. With infections in nearly every province, authorities warned 2019-nCoV appears to be spreading fast out of its epicenter.

The characterization appears supported by initial modeling. The virus’s basic reproduction number, a measure of the number of new cases per infection given no cap on available susceptibles, is clocking in at a healthy 3.11. That means in the face of such momentum, a control campaign must stop up to 75 percent of new infections to reverse the outbreak. The modeling team estimates there are presently over 21,000 cases, reported or not, in Wuhan alone.

Full-genome sequences of the virus meanwhile show few differences between the samples isolated across China. Slower spread for such a fast-evolving RNA virus would be marked by mutations accumulating place-to-place.

The coronavirus is starting to open up theaters overseas. Travelers with 2019-nCoV have been treated in Australia, France, Hong Kong, Japan, Malaysia, Nepal, Vietnam, Singapore, South Korea, Taiwan, Thailand, and the United States. Local outbreaks are now starting up within sink countries.

As the infection is characterized by human-to-human transmission and an apparent two-week incubation period before the sickness hits, the infection will likely continue to spread across the globe. Whether it’ll be Wuhan everywhere remains an open question.

The virus’s final penetrance worldwide will depend on the difference between the rate of infection and the rate of removing infections by recovery or death. If the infection rate far exceeds removal, then the total population infected may approach the whole of humanity. That outcome, however, would likely be marked by large geographic variation brought about by a combination of dead chance and the differences in how countries responded to their outbreak.

Pandemic skeptics aren’t so sure of such a scenario. Far fewer patients have been infected and killed by 2019-nCoV than even the typical seasonal influenza. But the mistake here is in confusing a moment early in an outbreak for a virus’s essentialist nature.

Outbreaks are dynamic. Yes, some burn out, including, maybe, 2019-nCoV. It takes the right evolutionary draw and a little luck to beat out chance extirpation. Sometimes enough hosts don’t line up to keep transmission going. Other outbreaks explode. Those that make it on the world stage can be game changers, even if they eventually die out. They upend the everyday routines of even a world already in tumult or at war.

The deadliness of any potential pandemic strain is the meat of the matter, of course. Should the virus prove less infectious or deadly than initially thought, civilization goes on, however many people are killed. The H1N1 (2009) influenza outbreak that worried so many a decade-plus ago proved less virulent than it first seemed. But even that strain penetrated the global population, and quietly killed patients, at magnitudes far beyond these first follow-up dismissals. H1N1 (2009) killed as many as 579,000 people its first year, producing complications in fifteen times more cases than initially projected from lab tests alone.

The danger here is found in humanity’s unprecedented connectivity. H1N1 (2009) crossed the Pacific Ocean in nine days, superseding predictions by the most sophisticated models of the global travel network by months. Airline data show a tenfold increase in travel in China just since the SARS epidemic.

Under such widespread percolation, low mortality for a large number of infections can still cause a large number of deaths. If four billion people are infected at a mortality rate of only 2 percent, a death rate less than half that of the 1918 influenza pandemic, eighty million people are killed. And unlike for seasonal influenza, we have neither herd immunity, nor a vaccine to slow it down.

Excerpted from: 'Connecting the Coronavirus to Agriculture'. Courtesy: Counterpunch.org