Scientists have found that even simple cloth masks provide significant protection and could reduce the spread of COVID-19.
The researchers from Johns Hopkins University and the University of Mississippi have used a model to recognize airborne transmission that is designed to be accessible to a wide range of people, including nonscientists.
Employing basic concepts of fluid dynamics, and therefore, the known factors in airborne transmission of diseases, the researchers propose the Contagion Airborne Transmission (CAT) inequality, model. While not all factors in the CAT inequality model may be known, it can still be used to assess relative risks, since the situational risk is proportional to the exposure time.
The researchers used this model to verify protection from transmission increases with physical distancing in an approximately linear proportion.
ALSO READ| Is My Mask Effective Against Corona?
Rajat Mittal, Author of the study, said, “If you double your distance, you generally double your protection.”
“This kind of scaling or rule can help inform policy.” Simple cloth masks provide significant protection and could reduce the spread of COVID-19. “We also show that any physical activity that increases the breathing rate and volume of people will increase the risk of transmission,” said Mittal.
“These findings can have important implications on the reopening of schools, gyms, or malls.”
The Drake equation has inspired the CAT inequality model of astrobiology and has developed a similar factorization based on the idea that airborne transmission occurs if a susceptible person inhales a viral dose that exceeds the minimum infectious dose.
The model includes variables that can be added at each of the three stages of airborne transmission: the generation, expulsion, and aerosolization of the virus-containing droplets from the mouth and nose of an infected host; the dispersion and transport via ambient air currents; and the inhalation of droplets or aerosols and the deposition of the virus in the respiratory mucosa in a susceptible person.
The researchers are hoping to look more closely at face mask efficiency and the transmission details in high-density outdoor spaces.
This model is based on the CAT inequality that could apply to the airborne transmission of other respiratory infections, such as flu, tuberculosis, and measles.