Ключевые слова: biological process, blood cells, disease, epidemic, health care, hmpv, human body, human influenza, illness, immune response, immune system, immunology, infection, infectious disease, inflammation, medical illustration, medical science, metapneumovirus, microbiology, microbiology research, microscopic organisms, pathogens, prevention of infections, respiratory tract infection, scientific illustration, spikes, spread of infection, viral attack, viral load, virology, virus, virus replication,