Induction of congenital hydrocephalus with mumps virus in rhesus monkeys

Molecular biology, pathogenesis and pathology of mumps virus

Mumps is caused by the mumps virus (MuV), a member of the Paramyxoviridae family of enveloped, non-segmented, negative-sense RNA viruses. Mumps is characterized by painful inflammatory symptoms, such as parotitis and orchitis. The virus is highly neurotropic, with laboratory evidence of central nervous system (CNS) infection in approximately half of cases. Symptomatic CNS infection occurs less frequently; nonetheless, prior to the introduction of routine vaccination, MuV was a leading cause of aseptic meningitis and viral encephalitis in many developed countries. Despite being one of the oldest recognized diseases, with a worldwide distribution, surprisingly little attention has been given to its study. Cases of aseptic meningitis associated with some vaccine strains and a global resurgence of cases, including in highly vaccinated populations, has renewed interest in the virus, particularly in its pathogenesis and the need for development of clinically relevant models of disease. In this review we summarize the current state of knowledge on the virus, its pathogenesis and its clinical and pathological outcomes.

[Measles, mumps and rubella virus infection in pregnancy. Possible adverse effects on pregnant women, pregnancy outcome and the fetus]

Measles, mumps and rubella are common childhood diseases. Therefore, frequent and intense contact with children of preschool age may be associated with a higher infection risk for childcare providers. This overview summarizes current knowledge on possible adverse effects of these infections on pregnant women, pregnancy outcome and the fetus. Acute rubella or mumps virus infections are apparently not more severe in pregnant than non-pregnant women. In contrast, measles virus infection in pregnancy is linked to a higher incidence of pneumonitis and hospitalization. Evidence of congenital defects due to fetal infection is only provided in case of rubella virus infection in early pregnancy. Following rubella virus infection in the first trimester an increased fetal loss rate was reported. In 1966, a prospective study showed also a significant association between maternal mumps in the first trimester and an increased risk of abortion. But other investigators could not confirm this association. Measles and rubella but not mumps virus infections are linked to an increased premature birth rate. Occurring in late pregnancy, all three infections can result in birth of an infected infant. But severe disease occurs rarely and is mostly reported for premature infants with early neonatal measles. Preventive measures, aimed to reduce the risk of infection or severe complications for pregnant childcare providers, should consider the individual history of the employee (e.g. previous immunizations or antibody test results), the current epidemiological situation and possible interventions like passive immunization in case of exposure to measles.

Unilateral hydrocephalus due to obstruction of the foramen of Monro: another complication of intrauterine mumps infection?

Unilateral hydrocephalus due to foramen of Monro-obstruction was diagnosed in a newborn who presented with macrocephaly at birth. The mother had mumps in the second trimester of pregnancy and immunological studies indicated possible intrauterine infection of the baby with mumps virus. His condition deteriorated rapidly, and he developed myoclonic seizures. The possible relationship of intrauterine mumps infection to neonatal neurological complications is discussed.

Multicystic encephalomalacia due to fetal viral encephalitis

Two children, aged 2 weeks and 2 months, with multicystic encephalomalacia aer described. Although computerized tomography (CT) scan was used for the diagnosis, the value of the simple method of transillumination is stressed. The mother of one child had mumps with meningitis at 26 weeks' gestation. The other child had an echovirus 11 isolated from the cerebrospinal fluid and herpesvirus hominis (HVH) from the skin at 8 weeks. We speculate that the changes in the brains of these babies may be due to the respective viruses causing a fetal encephalitis.