bio hazard cell corona Covid Covid-19 design illustration Nonpareils orange pandemic pollen sprinkles virus circle pattern green leaf pandemia plage plant snot darkness fruit macro photography red Virus Close-up aerolsol breathing clothline corona virus coronavirus corona cover covid 19 drying health hospital illness mask masks medical pegs prevention protection protective mask self-protection surgical carelessness corana virus coronavirus disposable hygiene medical equipment pollution sanitariness used waste accuracy antigen check checking colloidal covid-virus detection diagnosis diagnostic-aid dropper drops home-use immunochromatographic-technology kit limitations limited lysis-buffer measuring-instrument nasal-secretion negative-result plastic quality-control-C-line rapid rectangular result sample sampling-tube self-testing test test-cassette testing extraction-reagent-tube nasal sterile-swab swab adult-size careful commercial fabric face-mask filtered healthcare home-made layered layers material medical-equipment personal-protective-equipment PPE product protective-mask reusable Sanitary variety washable