Ключевые слова: 19, analysis, assistant, bacteria, biological, check, child, childhood, closeup, coli, comparison, concept, control, coronavirus, covid, definition, diagnosis, distribution, dna, doctor, genes, genetics, girl, gloves, hand, hospital, infection, laboratory, mask, material, medical, mouth, negative, nurse, office, pandemic, paternity, pediatrician, positive, protective, reception, relationship, reproduction, research, result, shelf, taking, test, tube,