Cytomegalovirus (CMV), also known as human herpes 5, is a double-stranded DNA virus. It is usually asymptomatic in immunocompetent individuals, but can present with severe diseases in immunocompromised individuals such as those with HIV/AIDS. It can cause retinitis, esophagitis, and retinitis pneumonia. On microscopic examination, infected cells can present with characteristic "owl eye" inclusion bodies. CMV is spread through body fluids such as saliva, urine, and sexual contact but can also be spread via transplanted organs.