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The teratogenic potential of three bunyaviruses, two California serogroup bunyaviruses, LaCrosse virus and San Angelo virus, and a Bunyamwera serogroup member, Main Drain virus, in sheep was studied following in utero inoculation of ewes in early gestation. Although Main Drain virus appeared to be most teratogenic, all three viruses induced a range of lesions including arthrogryposis, hydrocephalus, fetal death, axial skeletal deviations, anasarca, and oligohydramnios. The teratogenic effects of these viruses are identical to those described in ovine infections by Cache Valley and Akabane viruses. Demonstration of a common bunyaviral tropism for fetal tissue infection that results in congenital brain and musculoskeletal malformations provides evidence that human in utero infection by bunyaviruses could result in similar malformations in human infants.

We report an epidemic of 16 cases of measles during pregnancy. The risk factors for such an association and the materno-fetal outcomes are presented. The mean age of the patients was 20.6 years, with a mean gravidity and parity of 2.1 and 1.1 respectively. The mean clinical features were: conjunctivitis, hyperthermia and cutaneous rash. Nine maternal complications occurred: 6 laryngitis and 3 pneumopathies. All patients were HIV negative. The outcomes of the pregnancy were the following: 2 abortions, 3 stillbirths, 1 preterm delivery and 2 full term births. Eight patients with ongoing pregnancies were lost to follow-up after their discharge from the hospital. We conclude on the need for a systematic prevention in exposed pregnant women by immunotherapy and in children by immunization.

Background: We studied the possibility of detecting varicella-zoster virus in formalin-fixed tissue samples from a still-born infant with congenital anomalies in order to verify the relationship with maternal varicella., Case: A girl with hypoplasia of extremities, skin lesions, and microphthalmos was stillborn at 34 weeks' gestation. Her mother had had chickenpox between the 13th and 15th gestational weeks. Varicella-zoster virus DNA could be detected in formalin-fixed tissue samples of lungs, spleen, adrenal glands, bulbus oculi, and placenta by polymerase chain reaction (PCR). The method, with the use of primers from gene 29 encoding the major DNA-binding protein, proved to be highly sensitive. In addition, varicella-zoster virus DNA/antigens were localized in some organs by in situ hybridization/monoclonal antibodies., Conclusion: The PCR method should be included in the diagnosis of congenital varicella syndrome. The varicella-zoster virus can be detected in formalin-fixed tissue samples using this technique.

The association of varicella and pregnancy is very rare since 90% of women of reproductive age are immune. In the literature, a fetal varicella syndrome has been described characterized by multiple congenital malformations. We report here a case of intrauterine fetal death following maternal varicella at 17 weeks amenorrhea, with virological proof of fetal contamination. Because of the rarity of this association and by the same token of the fetal contamination during maternal varicella, the management during pregnancy rests essentially on a valid ultrasonic surveillance.

Objective: To compare the virulence of selected strains of porcine reproductive and respiratory syndrome virus (PRRSV) relative to reproductive performance of pregnant gilts., Design: 16 pregnant gilts (principals) were exposed oronasally to 4 strains (vaccine strain RespPRRS, field strains VR-2385, VR-2431, and NADC-8, 4 gilts/strain) of PRRSV on or about day 90 of gestation, 4 pregnant gilts (controls) were kept under similar conditions, except for exposure to PRRSV. Samples and specimens obtained from gilts, pigs (before ingestion of colostrum), and fetuses were tested for PRRSV and homologous antibody., Animals: 20 pregnant gilts., Procedure: The virulence of each strain of PRRSV was evaluated mainly on the clinical status of the corresponding litters at farrowing., Results: Most gilts remained clinically normal throughout the study and farrowed normally at or near the expected farrowing time. All virus strains crossed the placenta of principal gilts to infect fetuses in utero. The number of late-term dead fetuses (which appeared to be the best measure of relative virulence) ranged from 0 for litters of control gilts and gilts exposed to strain RespPRRS, to 38 for gilts exposed to strain NADC-8. All principal gilts became viremic and developed antibody against PRRSV. All strains persisted in alveolar macrophages of at least some principal gilts for at least 7 weeks after exposure., Conclusion: Strains of PRRSV vary in virulence., Clinical Relevance: The effects of PRRSV on reproductive performance are strain dependent and this should be considered in making a tentative diagnosis on the basis of clinical observations.

Objectives: To study the pathological features of fetuses dying because of parvovirus B19 infection, with particular reference to the presence of hydrops; to assess the usefulness of immunochemistry as a screening method for the detection of parvovirus infection at post-mortem examination., Design: Review of clinical, sonographic, serological and pathological data; immunohistochemical staining of post-mortem tissue., Sample: Cases of intrauterine fetal death occurring during the 18-month period January 1993 to June 1994 inclusive, referred for post-mortem examination to the Pathology Department, Royal Victoria Infirmary, Newcastle upon Tyne., Results: Eleven cases of fetal death due to parvovirus infection were identified. Seven fetuses were less than 18-week size. Three fetuses showed conspicuous hydropic change. One of the 11 cases was detected for the first time by retrospective immunochemical screening. Of cases originating from the Newcastle district, parvovirus infection was responsible for about 10% of all non-malformed fetal deaths occurring between 10 and 24 weeks of gestation referred for pathological examination., Conclusions: During the period of study, parvovirus infection was a relatively common cause of mid-trimester fetal death. Many fetuses dying because of this infection are not noticeably hydropic, and the possibility of parvovirus infection should be considered in any case of intrauterine fetal death. Immunochemistry can be used to confirm the histopathological diagnosis, and may be of particular help where there is advanced autolysis; immunohistochemical screening may detect occasional cases not initially identified by examination of routinely stained tissue sections.

Twenty-five strains of equine herpesvirus 1 (EHV-1) and one strain of equine herpesvirus 4 (EHV-4) isolated from material from various clinical cases in Denmark, together with reference EHV-1 and EHV-4 strains, were compared by restriction fragment pattern (RFP) analysis and inoculation of baby mice. The RFP analyses revealed that all EHV-1 strains belonged to genome type Ip. Four fetal isolates exhibited genomic characteristics that have been suggested as specific markers of the attenuated strain Rac H, widely used as a live vaccine. As the use of five vaccines against EHV-1 and EHV-4 has never been allowed in Denmark, it is assumed that Rac H derivatives have been acquired from visiting horses and thus are now circulating in the horse population. Baby mice inoculation revealed that four biotypes could be distinguished on the basis of pathogenicity. However, no strict correlation with pathogenicity in the natural host was seen.

Bovine pestivirus infection has been mainly recognized as the cause of mucosal disease, a syndrome which occurs sporadically in weaned and adult cattle as a late sequel to foetal infection during the first 3-4 months of gestation. Infection has also been associated with the occurrence of congenital malformations, especially of the central nervous system. Following the development of improved diagnostic and research techniques, pestivirus has now been shown to be associated with significant early reproductive loss including fertilization failure, embryonic mortality and abortion. The principal determinant of the outcome of in utero infection in the bovine is the age of the conceptus when infection occurs.

Infectious virus resembling type D simian retrovirus (SRV) was isolated from Ethiopian baboons (Papio cynocephalus) (SRV-Pc) housed at the University of Washington Regional Primate Research Center. When baboon peripheral blood mononuclear cells (PBMC) or tissues were cocultured with the H-9 human T-cell line or the Raji human B-cell line, large multinucleated syncytia positive for SRV-2 antigens were observed microscopically. Immunoblot analysis of purified SRV-Pc from cell culture supernatants demonstrated that the viral core and envelope proteins reacted with rabbit anti-SRV-2 serum. Fresh PBMC and cocultured cells were positive by polymerase chain reaction using two different sets of SRV-2 primers. Preliminary sequence analysis of two separate isolates from portions of the SRV-Pc p27 and gp20 regions revealed homology with SRV-1, SRV-2, and Mason-Pfizer monkey virus. The homologies in the p27 segment were 91-94% and the homologies in the gp20 segment were 72-75%.

We present a case of human parvovirus B19 infection in a term pregnancy that resulted in rapid development of hydrops fetalis and death. Clinical aspects of this virus in pregnancy and therapeutic options are discussed.

The results of morphological studies of 66 placentas from women suffering from various forms of viral hepatitis and HBs antigen carriers as well as results of a pathomorphological study of a late abortion, 3 stillborns and 2 newborns are presented. 33 placentas showed lymphocytic infiltration of varying degree and vasculitis. Of most importance were cellular changes, particularly in the decidua, with the appearance in the nuclei of inclusions similar to those found in the liver affected with viral hepatitis. A correlation is observed in some cases between liver changes in the mother, placental alterations and changes in the child.