Cytomegalovirus

MICROBIOLOGY

• Ubiquitous, large, enveloped dsDNA betaherpesvirus; establishes lifelong latency after primary infection.
• Transmitted sexually or by close contact, blood or tissue exposure, perinatally. Cultured from urine, blood, throat, tears, stool, cervix, semen, breast milk.
• Seroprevalence increases with age. Adult seroprevalence rates range from 40-100% and are highest in developing countries.
• Exhibits slow growth in cultured cells (can be up to 6 weeks until cytopathic effect is detected in tissue culture) and cytopathology is characterized by large cells with nuclear (Cowdry owl’s eye) and cytoplasmic inclusions.
• Isolation of virus or detection of viral proteins or nucleic acid defines CMV infection. Presence of signs/symptoms of end organ disease + CMV infection = CMV disease.