The laboratory diagnosis of measles virus infection uses a Mumps Virus Antibody IgG test. The highly contagious viral disease known as the mumps is spread through the inhalation of respiratory droplets or secretions that are contaminated. In cases with symptoms including fever, headache, muscle soreness, and salivary gland enlargement, the test is advised. The presence of IgG-class antibodies is a sign of past infection with or immunisation against the mumps virus. Those who test positive are thought to be immune to the mumps virus. In contrast, the absence of IgG antibodies indicates no prior exposure to the virus and no specific immunological response after immunisation.