A Virologist and Specialist in Coronaviruses and Respiratory Diseases Explains – Centre for Research on Globalization
SARS and MERS were not very contagious for respiratory viruses, and from an epidemiological point of view we knew for example that the contagion only happened when the patient was already sick for 4-5 days, which explains that for these two epidemics the virus was spread mostly to relatives and attending medical staff.
Our public health measures are not suitable for COVID-19
By contrast, COVID-19 is transmitted before the onset of symptoms, which implies that public health measures which could control a virus like SARS and MERS (but only if they were rigorously applied, with quarantine of people returning from risk area, and mass screening), could never be sufficient to contain such a contagious virus.
This contagiousness, comparable to that of rubella or mumps before vaccination, implies that this virus can only spread like wildfire in an immunologically naive population. And a virus capable of being transmitted by aerosol can only explain this contagiousness; it is a property of practically all respiratory viruses, SARS and MERS being notable exceptions to the rule.
The WHO has in fact admitted in a press release that aerosol transmission is possible and requires more study, when we don’t have time for more study. I worked in an institute dedicated to respiratory diseases and there the work on aerosols, chemical or infectious, is done every day, it is perhaps 10% of their activities; I have absolutely no doubt that this virus is transmitted by aerosol, if I can leave my reserve as a scientist who must doubt everything. In an emergency situation, we follow the preponderance of evidence.
The recipe for successful countries is: sanitary cordon, screening of travelers, massive use of adequate masks by the population, quarantine when necessary, surveillance of respiratory diseases, massive screening, tracing of possible contacts, and early hospitalization when necessary. But you have to be organized before the pandemic to be able to apply this recipe.