Method for measuring type a influenza virus

Disclosed is a method for measuring a type A influenza virus through an immunoassay employing an anti-type A influenza virus monoclonal antibody having high reactivity to a wide range of subtypes. This method for measuring a type A influenza virus includes a step for measuring a type A influenza virus through an immunoassay utilizing an antigen-antibody reaction of a monoclonal antibody, or an antigen-binding fragment thereof, that specifically reacts with a matrix protein (M1) of a type A influenza virus, and a type A influenza virus in a specimen. 本发明公开了甲型流感病毒的测定方法，该方法是通过使用与广泛的亚型反应性高的抗甲型流感病毒单克隆抗体进行免疫测定。该方法包括通过利用下述抗原抗体反应的免疫测定来测定甲型流感病毒：与甲型流感病毒的基质蛋白(M1)特异性反应的单克隆抗体或其抗原结合性片段与检样中的甲型流感病毒的抗原抗体反应。