Epidemiologists use different indicators to understand the danger of the coronavirus. Here are three infographics to compare 2019-nCov, as we know it in early February 2020, with other viruses.
Nearly a month after the start of the epidemic, the coronavirus that appeared in Wuhan has killed more than 560 people, and the number of people affected has exceeded 28,000, mainly in mainland China, according to figures provided by Beijing available on Thursday. February 6th. How dangerous is the 2019-nCov virus compared to other diseases? The Ebola virus, SARS, the seas, the H1N1 flu or the seasonal flu: each virus has specific epidemiological characteristics.
>> Follow the latest information about the 2019-nCoV epidemic live
Less lethal than SARS, more than measles
To estimate the danger of the coronavirus, the scientific community is trying to define a fatality rate, which corresponds to the number of deaths divided by the number of clinical cases observed. It is still too early to define this rate for the coronavirus, but there have already been, as of February 6, 2020, 565 deaths out of more than 28,200 cases identified, representing a rate of 2%, according to figures recorded by Johns University. Hopkins of Baltimore (United States), who closely follows the evolution of the epidemic. The coronavirus therefore appears to be less lethal than HIV (when not treated) or Ebola, but more than the H1N1 flu or measles. The Ebola virus, for example, kills 63% of those infected.
More contagious than H1N1 flu, less than chickenpox
Another fundamental indicator in the observation of viruses is the level of contagion, that is to say its ability to be transmitted. Epidemiologists use the “basic reproduction rate”, or R0, for this. If this index is equal to 5, this means that each patient infects an average of five people. Again, it is too early for the scientific community to accurately calculate the 2019-nCoV virus contagiousness index, but a Chinese study published in the medical journal New England Journal of Medicine (in English) estimated it at 2.2. Other researchers rate it between 1.5 and 3.5. It is much less than measles, for example, with which an patient infects an average of 12 people.
An exponential increase in the number of cases
The rate of contagion of coronavirus can seem minimal, compared to that of measles or hepatitis B. It should however be borne in mind that this index, evaluated in January, in the first weeks, is very temporary. It may change, in particular, depending on the measures taken by the authorities. At the beginning of February, the available data indicate a much faster spread than that of other known coronaviruses. Data from the World Health Organization (WHO) shows that the epidemic of SARS – another coronavirus – had affected just over 8,000 people between November 2002 and July 2003. The 2019-nCoV virus has exceeded this figure in less than a month, from January 30, 2020, and the number of affected patients is now growing exponentially.
–
