lots of bacteria and viruses in the air and in particles, virus transfer by airborne droplets, concept.

air airborne bacteria bacteriological bacterium biology cleanliness coli collection concept contact corona coronavirus covid19 disease droplets element epidemic escherichia flu global hand hands handshake health human hygiene illustration immune infection infectious lots mers micro microbes microbiology microworld migration mikroorganizmy ncov organism outbreak palm pandemic pandemics particles quarantine retrovirus risk sanitizer sars sick transfer tuberculosis various vector virological virology virus viruses wash