Ключевые слова: bacteria, black, clean, contamination, coronavirus, covid19, disease, droplet, equipment, fabric, face mask, flu, folded, germ, gradient, gray, health, healthcare, hygiene, ink, liquid, mask, medical, monochrome, pandemic, prevention, protection, protective mask, safety, sanitary, shadow, smooth, splash, spread, sterile, still life, studio shot, top view, virus,