Viral infections in pregnancy

Community influenza activity and risk of acute influenza-like illness episodes among healthy unvaccinated pregnant and postpartum women

This study investigated the relation between weekly levels of influenza activity and the risk of acute influenza-like illness episodes among 8,323 healthy pregnant and postpartum women enrolled in a Puget Sound region, Washington, health maintenance organization, Group Health Cooperative, between June 1991 and December 1997. The authors classified weeks between October and May for isolate activity level based on surveillance data for influenza, respiratory syncytial virus, parainfluenza, and adenovirus infection. Influenza-like illness episodes were identified from medical encounters assigned a diagnostic code consistent with a symptomatic influenza infection. The authors compared the occurrence of influenza-like illness episodes within each pregnancy stage for periods with varying levels of influenza isolate detection in the community. Repeated-measures logistic regression methods accounted for time-dependent factors. The adjusted strength of association between influenza exposure and influenza-like illness episodes increased as the pregnancy stage progressed (first trimester odds ratio = 1.12, 95% confidence interval: 0.79, 1.59; second trimester odds ratio = 1.30, 95% confidence interval: 0.97, 1.73; third trimester odds ratio = 1.84, 95% confidence interval: 1.31, 2.59; postpartum period odds ratio = 2.28, 95% confidence interval: 1.42, 3.68). Pregnancy stage modified the association between influenza activity and influenza-like illness episodes. Findings estimate that 20-43 pregnant/postpartum women would need to be vaccinated with an 80% effective vaccine to prevent one influenza-like illness episode.

Herpes simplex virus hepatitis in pregnancy: a clinicopathologic study of three cases

Herpes simplex virus (HSV) hepatitis is rare in adults, usually occurring in immunocompromised individuals and in otherwise healthy women in the third trimester of pregnancy. Three cases of HSV hepatitis occurring in pregnant women were diagnosed at our institution between 1981 and 1990. This diagnosis was not suspected clinically, and in each case was made on the basis of histology, immunoperoxidase studies, and viral cultures of liver tissue. Clinically, the patients had severe anicteric liver failure with markedly elevated serum aspartate aminotransferase and alanine aminotransferase levels; two of the three patients died. None had mucocutaneous lesions at the time of diagnosis. Histologically, two distinct patterns of necrosis and inflammation were seen. Two of the cases had well-demarcated foci of necrosis scattered randomly throughout the lobules with neutrophilic infiltration, giving the impression of abscess formation. Hepatocytes at the periphery of these areas of necrosis had enlarged nuclei with "ground-glass" inclusions; however, no Cowdry type A inclusions were seen. Rare multinucleated cells were present. Immunoperoxidase staining using antibodies to HSV was positive primarily in the hepatocytes with inclusions. The third case had diffuse, almost total hepatic necrosis with no viral inclusions and virtually no inflammatory response. This histologic pattern is similar to that seen in neonates with HSV infection. Immunoperoxidase studies in this case were negative; however, viral cultures were positive. While HSV hepatitis may be suspected or diagnosed on the basis of histology alone, viral cultures are an important adjunct since viral inclusions may be absent. Prompt diagnosis is important since antiviral therapy is now available.

Viral infections during pregnancy: a guide for the emergency physician

Emergency physicians are frequently called on to treat or advise pregnant patients. When faced with a pregnant patient who has clinical evidence of or exposure to a viral illness, the emergency physician must be aware of the potential maternal and fetal risks posed by various viral agents. This review provides current, accurate information and guidance for the pregnant patient.

Trends in neonatal infections

The changing epidemiology of neonatal infections manifested in the first few weeks of life is described. The six infections discussed are herpes, hepatitis B, chlamydial infection, infection due to the group B streptococcus, gonococcal disease, and acquired immunodeficiency syndrome. Nursing actions to prevent the spread of these diseases are described, with particular emphasis on the importance of body substance precautions for all neonates.