What harm does virus do to human body and how to harm human health?

Viruses and some bacteria in the air are the main pathogens of human body, and many diseases such as influenza and hepatitis are spread by airborne pathogens. Although bacteria and viruses are small in size, they are often adsorbed on several times larger particles in the form of colonies or spores because they cannot live alone in the air. In particular, viruses, because they do not have a complete metabolic system, must be parasitic in some living cells to reproduce. Therefore, scientists generally regard bacteria and viruses as suspended particles of 4 ~ 10 micron. The air purifier of Jin Kang Dudu Company adopts high-efficiency air filter, which can filter out particles as small as 0.3 micron, so the removal effect of bacteria and viruses in the air is very obvious.