According to some health care Doctors
Using tear gas or pepper spray to subdue protesters will only help spread the coronavirus in the middle of a pandemic, infectious disease experts warn, urging law enforcement to abandon the practice for public health reasons.

Spraying people with tear gas causes them to cough, shout and scream — and that will send infectious droplets from an infected person to others,

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Long Term Effects of Tear Gases on Respiratory System: Analysis of 93 Cases

"The mostly used agents among tear gases are 2-chlorobenzylidene malononitrile (CS), oleoresincapsicum (OC), and chloroacetophenone (CN) [1, 2]. The usage types of tear gases are gas bomb and spray. The main effect of “Riot Control Agents” is irritation of mucosal surfaces."

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It helps spread the virus by the increase in coughing and sneezing that occurs with tear gas use.