Ключевые слова: adult, air, allergy, asia, asian, background, breathing, care, caucasian, concept, disease, diseases, dust, environment, face, female, fever, filter, flu, girl, h1n1, health, healthy, human, infection, influenza, lady, mask, medical, patient, people, person, pm25, pollution, prevention, protect, protection, protective, respiratory, safety, sick, smoke, surgical, toxic, virus, wear, wearing, white, woman, young,