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Covid-19: identifying and isolating asymptomatic people helped eliminate virus in Italian village

BMJ 2020; 368 doi: (Published 23 March 2020) Cite this as: BMJ 2020;368:m1165

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Preventing a COVID-19 pandemic flashover

Dear Editor,

In sciences dealing with compartment fire and fire hazards, flashover stands for a near-simultaneous ignition of the combustible material in a compartment. After flashover, the temperature promptly increases, rising to its maximum value in a Gaussian fashion. Flashover depends on the size of the room, burning materials, heat release rate of each material, threshold temperature (auto ignition temperature), and so on. Mathematical comparison can be drawn between flashover’s spatial pattern variation and the current COVID-19 worldwide spread.

During fire, the air moves and increases heat transfer; in the same way, people move and spread the disease. Flashover is not mandatory for fire: it depends on the materials involved. This is the case in disease, where the mean age of people stands for the type of burning material: if people are old or sick the likelihood increases. Even taking into account additional parameters (such as geographic location, occurrence of airports, number of swabs performed, etc.), things are similar, making the problem of a COVID-19 flashover a painstaking issue.

A worldwide flashover is not an imminent danger, however compartment flashover (in a country) might be unfortunately the case. What happens if nobody puts in regulations? Will COVID-19 spread behave like fire, possibly leading to a catastrophic local flashover? Therefore, it’s time to restrict people’s spreading: with additional regulations to prevent crowd movements and individual contacts, flashover can be prevented.

Flavia-Corina Mitroi-Symeonidis
Police Academy "Alexandru Ioan Cuza", Fire Officers Faculty, Bucharest, Romania.
Academy of Economic Studies, Department of Applied Mathematics, Bucharest, Romania.

Ion Anghel
Police Academy "Alexandru Ioan Cuza", Fire Officers Faculty, Str. Morarilor 3, Sector 2, Bucharest RO-022451, Romania.

Arturo Tozzi
Center for Nonlinear Science, Department of Physics, University of North Texas, Denton, Texas, USA

Competing interests: No competing interests

23 March 2020
Flavia-Corina Mitroi-Symeonidis
Applied mathematics
Ion Anghel, Arturo Tozzi
Academy of Economic Studies, Bucharest, Romania
Str. Morarilor 3, Sector 2, Bucharest RO-022451, Romania