特異性:This item exhibits nuclear staining in immunofluoresence and is therefore thought to recognize a nuclear protein. Influenza virus type B is a genus in the virus family Orthomyxoviridae, responsible for acute respiratory illnesses in humans. It varies antigenically from influenza virus types A and C and is not divided into any subtypes. The gradual evolution of Influenza virus type B occurs via a series of mutations known as antigenic drift, in the surface glycoprotein haemagglutinin (HA), enabling the virus to evade the immune system and potentially re-infect the same host. HA glycoproteins from the Influenza virus type B are included in the annually updated trivalent flu vaccine, along with the Influenza virus type A subtypes H3N2 and H1N1.