Cytomegalovirus.

Abstract

OverviewCytomegalovirus (CMV) is a common herpes virus that infects between 50% and 85% of adults in the United States (Centers for Disease Control [CDCI, 1995). It is part of the same group that contains viruses that cause infectious mononucleosis (Epstein-Banvirus), chicken pox, and shingles (Children's Biomedical Research Institute [CBRII, 1989; CDC, 1995). For the most part, the virus remains nonsymptomatic with no long-term health implications (CBRI, 1989; CDC, 1995). However, CMV infection can have adverse outcomes for individuals with impaired immune systems or for the unborn children of the 1-3% of women who become infected for the first time during pregnancy (CDC, 1995;Marshall, Rabalais, Stewart, & Dobbins, 1993).CMV is the leading cause of infection in newborns (CDC, 1995). Approximately 1%, or 40,000 infants, are infected annually during gestation (Raynor, 1993), with up to 10% acquiring the virus during delivery or through breast milk (Adler, 1992;Minamishima et al., 1994). Complications of the virus are varied. Children who become infected with CMV after birth have few symptoms that, when they occur, resemble those of a generalized infection (CDC, 1995; Lajo, Borque, Del Castillo, & Martin-Ancel, 1994). In children infected in utero, complications may range from mild to severe. Although 85-90% of infants infected in utero are asymptomatic (CDC, 1995), these "clinically silent" children may be at risk for audiological, neurological, and developmental problems later in life (An dersen, 1988;Williamson, Demmler, Percy, & Catlin, 1992). The remaining 10-15% may experience neurological damage such as hearing impairments, psychomotor delays, and learning problems (CBRI, 1989;Raynor, 1993). In addition, some impairment in the visual, auditory, motor, and social areas may be progressive (CDC, 1995;O'Brien & Goldberg, 1992).The more severe forms of the disease affects approximately 1 in 1,000 US.-born infants (CBRI, 1989) and is fatal for approximately 30% (Jones & Isaacs, 1995;Raynor, 1993). Clinical manifestations include microcephaly (abnormal smallness of the head or cranial area), jaundice (yellow skin, tissue, and body fluid pigmentation caused by bile deposits), liver and spleen infection, pneumonia, cardiac anomaly, chorioretinitis, and CMV mononucleosis (CBRI, 1989). The most severe manifestation, cytomegalic 2 13