Cytomegalovirus IgG is one of the serological tests for cytomegalovirus, which is commonly found in nature and is an opportunistic pathogen. A positive cytomegalovirus IgG usually refers to a positive cytomegalovirus IgG antibody, representing a previous infection with cytomegalovirus, but the body’s immune system has recognized and cleared the cytomegalovirus. Of course, it is also possible that the infection is currently present. If the concentration of cytomegalovirus IgG antibodies is significantly higher than normal, there may be a current infection, and if the IgG concentration tends to increase continuously, there may be a secondary infection. Cytomegalovirus infection is common in humans, and most people who are infected have no clinical symptoms and have an insidious or latent infection. When the infected person is immunocompromised, such as during pregnancy, organ transplantation, and tumor patients, this can lead to cytomegalovirus activation and the development of clinical symptoms. People with normal immune function are usually asymptomatic and do not require treatment after cytomegalovirus infection. In addition, during viral infection, cytomegalovirus IgG antibodies rise slowly, and even if the virus is cleared by the body’s immune system, IgG antibodies are carried, and when relevant tests are performed, a positive cytomegalovirus IgG condition may be found. If the cytomegalovirus infection is cured and antibodies are produced in the body, this condition does not require special treatment and can be improved by improving a poor lifestyle. If cytomegalovirus infection currently exists in the body, it should be treated in a regular hospital, and usually antiviral treatment with drugs such as acyclovir and other antiviral drugs will be used clinically. People with low immune function, such as those who use immunosuppressants or hormones for a long time, infection with cytomegalovirus can cause diseases such as cytomegalovirus pneumonia, hepatitis and enteritis, which need to be given relevant treatment according to the manifestation of the disease.