Enhancement of cytomegalovirus infection during pregnancy in guinea pig.

The effects of pregnancy on primary acute and chronic persistent infection with cytomegalovirus (CMV) were examined in the guinea pig model. Pregnant guinea pigs developed a more severe acute CMV infection than did nonpregnant animals. High death rate, pronounced splenomegaly, interstitial pneumonia, and necrosis with inclusions in various tissues were observed only in pregnant animals. Acutely infected pregnant animals also differed from nonpregnant animals by the absence of tissue inflammation and by a delay in the peripheral lymphoproliferative response. During persistent infection, salivary gland virus titers were significantly higher in pregnant animals than in nonpregnant guinea pigs. These results indicate that during acute guinea pig CMV infection, virus clearance and recovery from clinical disease are altered in the pregnant host. Furthermore, enhancement of persistent chronic guinea pig CMV infection occurs in the salivary glands during pregnancy.