PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “parvovirus”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources

Incidence of parvovirus B19 infection among an unselected population of pregnant women in the Netherlands: A prospective study.

OBJECTIVE: To evaluate seroprevalence of anti-parvovirus B19 IgG immunoglobulins and the rate of seroconversion in seronegative pregnant women. DESIGN: Prospective assessment of anti-parvovirus B19 IgG immunoglobulins in an unselected population of pregnant women booked for antenatal care from 1998 to 2000. SETTING: Maternity departments of an academic hospital and four affiliated teaching hospitals in the Netherlands. SUBJECTS: Two thousand five hundred and sixty seven pregnant women. MAIN OUTCOME MEASURES: Seroprevalence of anti-parvovirus B19 IgG immunoglobulin in the first trimester of pregnancy and subsequent seroconversion in those women who were tested negative for parvovirus B19 antibodies in the first trimester of pregnancy. RESULTS: The estimated seroprevalence of anti-parvovirus B19 IgG immunoglobulins among the study population is 70% (95% CI: 68-71) in the first trimester of pregnancy. Seven hundred and seventy nine women tested negative for parvovirus B19 antibodies in the first trimester of pregnancy. Paired testing in these women confirmed 18 seroconversions. Based on these findings the estimated incidence of maternal parvovirus B19 infection in this population among seronegative Dutch women is 2.4% (95% CI: 1.4-3.7). CONCLUSION: Maternal infection with parvovirus B19 is relatively common. However, it is argued that in the Netherlands routine assessment of parvovirus antibodies in pregnant women is not warranted as there is a low risk of adverse fetal outcome and measures to prevent the parvovirus B19 infection and its consequences are very limited.

Adolescent↗

Assessment of the specificity of a commercial human parvovirus B19 IgM assay.

BACKGROUND: It is important to investigate a possible cross-reaction of anti-rubella IgM in the IDEIA Parvovirus B19 IgM test because many B19 infections are either asymptomatic or have clinical symptoms similar to those of rubella virus infections. Epstein-Barr virus (EBV) IgM, cytomegalovirus (CMV) IgM, measles IgM and rheumatoid factor (RF) IgM cross-reactions were also studied. OBJECTIVES: In the period from February to September 1994 (including a parvovirus B19 epidemic) more than 10,000 serum samples were examined for parvovirus B19 IgM in Denmark. This gave an opportunity to evaluate the commercial IDEIA Parvovirus B19 ELISA kit (DAKO A/S, Glostrup, Denmark), which was used routinely at Statens Serum Institut from the beginning of 1994 and onwards. STUDY DESIGN: A total of 123 parvovirus B19 IgM positive sera were tested for reactivity in rubella IgM EIA. A total of 78 rubella IgM positive sera, 60 EBV VCA-IgM positive sera, 30 CMV IgM positive sera and 24 measles virus IgM positive sera were tested for reaction in IDEIA Parvovirus B19 IgM test. Finally, 25 parvovirus IgM positive sera were tested for specific IgM against measles virus, EBV (VCA), CMV and for RF. RESULTS: One anti-B19 IgM positive serum sample reacted positively in the rubella IgM test. Of rubella IgM positive serum samples 4% cross-reacted in IDEIA Parvovirus B19 IgM test, as did 17 and 20% of EBV VCA-IgM and CMV IgM positive serum samples respectively. None of measles virus IgM positive serum samples cross-reacted in the IDEIA Parvovirus B19 IgM test. Of 25 initially parvovirus B19 IgM positive sera 20% cross-reacted in EBV VCA IgM test and 8% in the CMV IgM test. None reacted positively in measles virus IgM test; 28% showed weak reactivity in RF IgM test. CONCLUSIONS: Precautions must be taken when results of IgM assays are interpreted. Epidemiological and clinical observations must be considered.

Antibodies, Viral↗

Molecular characterization of newly recognized rodent parvoviruses.

Several autonomous rodent parvoviruses distinct from the prototypic rodent parvoviruses have been isolated. These include variants of a mouse parvovirus (MPV), a hamster isolate designated hamster parvovirus (HaPV), and a variant strain of minute virus of mice (MVM) designated MVM-Cutter or MVM(c). In this study, the DNA sequence of the coding regions of the viral genome and the predicted protein sequences for each of these new isolates were determined and compared to the immunosuppressive and prototypic strains of MVM [MVM(i) and MVM(p)], the rodent parvovirus H-1, and LuIII, an autonomous parvovirus of uncertain host origin. Sequence comparisons showed that the MPV isolates were almost identical, HaPV was very similar to MPV, and MVM(c) was most similar to MVM(i) and MVM(p). Haemagglutination inhibition assays revealed that MPV and HaPV represent two serotypes distinct from previously characterized rodent parvovirus serotypes while MVM(c) belongs to the MVM serotype. Each of the newly isolated rodent parvoviruses was shown to encapsidate a predominantly negative-sense 5 kb DNA genome and to encode two nonstructural proteins (NS1 and NS2) and two structural viral proteins (VP1 and VP2). These studies indicate that MPV and HaPV are autonomous parvoviruses distinct from previously characterized parvoviruses and MVM(c) is a variant strain of MVM distinct from MVM(i) and MVM(p).

Amino Acid Sequence↗

Experimental infection of cynomolgus monkeys with simian parvovirus.

Simian parvovirus is a recently discovered parvovirus that was first isolated from cynomolgus monkeys. It is similar to human B19 parvovirus in terms of virus genome, tropism for erythroid cells, and characteristic pathology in natural infections. Cynomolgus monkeys were infected with simian parvovirus to investigate their potential usefulness as an animal model of human B19 parvovirus. Six adult female cynomolgus monkeys were inoculated with purified simian parvovirus by the intravenous or intranasal route and monitored for evidence of clinical abnormalities; this included the preparation of complete hematological profiles. Viremia and simian parvovirus-specific antibody were determined in infected monkeys by dot blot and Western blot assays, respectively. Bone marrow was examined at necropsy 6, 10, or 15 days postinfection. All of the monkeys developed a smoldering, low-grade viremia that peaked approximately 10 to 12 days after inoculation. Peak viremia coincided with the appearance of specific antibody and was followed by sudden clearance of the virus and complete, but transient, absence of reticulocytes from the peripheral blood. Clinical signs were mild and involved mainly anorexia and slight weight loss. Infection was associated with a mild decrease in hemoglobin, hematocrit, and erythrocyte numbers. Bone marrow showed marked destruction of erythroid cells coincident with peak viremia. Our findings indicate that infection of healthy monkeys by simian parvovirus is self-limited and mild, with transient cessation of erythropoiesis. Our study has reproduced Koch's postulates and further shown that simian parvovirus infection of monkeys is almost identical to human B19 parvovirus infection of humans. Accordingly, this animal model may prove valuable in the study of the pathogenesis of B19 virus infection.

Animals↗

Alpha5beta1 integrin as a cellular coreceptor for human parvovirus B19: requirement of functional activation of beta1 integrin for viral entry.

Replication of the pathogenic human parvovirus B19 is restricted to erythroid progenitor cells. Although blood group P antigen has been reported to be the cell surface receptor for parvovirus B19, a number of nonerythroid cells, which express P antigen, are not permissive for parvovirus B19 infection. We have documented that P antigen is necessary for parvovirus B19 binding but not sufficient for virus entry into cells. To test whether parvovirus B19 utilizes a cell surface coreceptor for entry, we used human erythroleukemia cells (K562), which allow parvovirus B19 binding but not entry. We report here that upon treatment with phorbol esters, K562 cells become adherent and permissive for parvovirus B19 entry, which is mediated by alpha 5 beta 1 integrins, but only in their high-affinity conformation. Mature human red blood cells (RBCs), which express high levels of P antigen, but not alpha 5 beta 1 integrins, bind parvovirus B19 but do not allow viral entry. In contrast, primary human erythroid progenitor cells express high levels of both P antigen and alpha 5 beta 1 integrins and allow beta1 integrin-mediated entry of parvovirus B19. Thus, in a natural course of infection, RBCs are likely exploited for a highly efficient systemic dissemination of parvovirus B19.

Cell Adhesion↗

Detection of human parvovirus B19 in a patient with hepatitis.

Parvovirus B19 has been associated by some investigators with cases of severe hepatitis. The aim of the present study was to determine the presence of active parvovirus B19 infection among 129 Brazilian patients with non-A-E hepatitis. The patients were assayed for antibodies against parvovirus B19, IgM class, by ELISA. In IgM-positive cases, parvovirus B19 DNA was assayed by PCR in serum and liver tissue and parvovirus VP1 antigen in liver tissue was assayed by immunohistochemistry. Antibodies against parvovirus B19, IgM class, were detected in 3 (2.3%) of 129 patients with non-A-E hepatitis. Previous surgery and blood transfusions were reported by these 3 patients. One patient was a 56-year-old female with severe hepatitis, with antimitochondrial antibody seropositivity and submassive necrosis at liver biopsy, who responded to corticosteroid therapy. Strong evidence for active parvovirus B19 infection was found in this patient, with parvovirus B19 DNA being detected by PCR in liver tissue. Furthermore, parvovirus VP1 antigen was also detected in liver tissue by immunohistochemistry. The other two IgM-positive patients were chronic hepatitis cases, but active infection was not proven, since neither viral DNA nor antigen were detected in their liver tissues. This and other reports suggest a possible relation between parvovirus B19 infection and some cases of hepatitis.

Acute Disease↗

The use of monoclonal antibody R92F6 and polymerase chain reaction to confirm the presence of parvovirus B19 in bone marrow specimens of patients with acquired immunodeficiency syndrome.

BACKGROUND: Parvovirus B19 infection is a cause of chronic anemia and red cell aplasia in patients with acquired immunodeficiency syndrome (AIDS) and in other immunocompromised hosts. Anemia in AIDS patients has a multifactorial etiology, with parvovirus B19 infection being an infrequent but nevertheless treatable cause. Therapy with intravenous immune globulin can result in rapid improvement of parvovirus-induced anemia. This treatment is expensive, therefore accurate and rapid confirmation of parvovirus infection is important in providing appropriate and cost-effective therapy. METHODS: Bone marrow samples from 2 AIDS patients with severe anemia and reticulocytopenia were studied. Bone marrow morphology and serologic studies were evaluated for parvovirus B19 infection. An immunohistochemical method using a monoclonal antibody, R92F6, to B19 capsid proteins was utilized on decalcified, B5-fixed, paraffin-embedded bone marrow biopsies. Bone marrow aspirate cells were examined by electron microscopy for evidence of viral particles. In addition, polymerase chain reaction (PCR) studies using a nested PCR assay to the parvovirus B19 viral genome were performed in a case for which fresh cells were available. RESULTS: Bone marrow findings included marked erythroid hypoplasia with characteristic giant pronormoblasts and intranuclear inclusions. Serologic studies were negative in one case, while the second case showed positive parvovirus B19 immunoglobulin M antibody. Immunohistochemical studies for parvovirus B19 were positive in both cases. The presence of intranuclear virions was demonstrated by electron microscopy and was confirmed by PCR analysis. Both patients were treated with intravenous immune globulin, and subsequent improvement was noted. CONCLUSIONS: Both immunohistochemistry and PCR studies on bone marrow specimens from AIDS patients with anemia are rapid and sensitive methods for the confirmation of parvovirus B19 infection. They are valuable tools, particularly when serologic studies are negative. When PCR is not available, immunohistochemical methods can be useful. The rapid confirmation of parvovirus B19 infection will allow for early and cost-effective therapy.

Acquired Immunodeficiency Syndrome↗

Parvovirus B19 infection in pregnancy.

OBJECTIVES: (1) To review the effects of parvovirus B19 on the pregnant woman and fetus, and (2) to discuss the management of women who are exposed to, who are at risk of developing, or who develop parvovirus B19 infection in pregnancy. OUTCOMES: Maternal outcomes of parvovirus B19 including erythema infectiosum, arthropathy, anemia, and myocarditis. Fetal outcomes including spontaneous abortion, congenital anomalies, hydrops fetalis, stillbirth, and long-term effects. EVIDENCE: MEDLINE search from 1966 to January 2002 for articles relating to parvovirus B19 infection, using key words "parvovirus" and "pregnancy," and guidelines of professional organizations including the American College of Obstetricians and Gynecologists. VALUES: The evidence obtained was reviewed and evaluated by both the Maternal Fetal Medicine and Infectious Diseases Committees of the Society of Obstetricians and Gynaecologists of Canada (SOGC) and recommendations were made according to guidelines developed by the Canadian Task Force on the Periodic Health Examination. RECOMMENDATIONS: 1. Pregnant women exposed to, or who develop symptoms of, parvovirus B19 infection should be assessed to determine if they are susceptible to infection (nonimmune) or if they have a current infection, by determining their parvovirus B19 IgG and IgM status. (II-2A) 2. If parvovirus B19 IgG is present and IgM is negative, the woman is immune and can be reassured that she will not develop infection and that the virus will not adversely affect her pregnancy. (II-2A) 3. If both parvovirus B19 IgG and IgM are negative (and the incubation period has passed), the woman is not immune and has not developed the infection. Although she may wish to minimize further exposure, leave from the workplace is controversial and is not routinely recommended. Further studies are needed in this area. (III-B) 4. If a recent parvovirus B19 infection has been diagnosed in the woman, then referral to an obstetrician or a maternal-fetal medicine specialist should be considered (III-B). The woman should be counselled regarding risks of fetal transmission, fetal loss, and hydrops. Serial ultrasounds should be performed up to 8 to 12 weeks after infection to detect the development of hydrops (III-B). If hydrops develops, referral to a maternal-fetal medicine specialist should be made and consideration should be given to fetal blood sampling and intravascular transfusion (II-2B). VALIDATION: These guidelines have been reviewed and approved by the Maternal Fetal Medicine and Infectious Diseases Committees of the SOGC, and the Council of the SOGC.

Decision Trees↗

Detection of parvovirus B19 infection in first and second trimester fetal loss.

Fetal and placental tissues and maternal sera from a series of 273 cases of first and second trimester fetal loss were collected to detect the frequency of parvovirus B19 infection. In addition, fetal tissues were studied for the presence of congenital anomalies. Serology of maternal sera, histology of fetal tissues and placenta, polymerase chain reaction (PCR), in situ hybridization (ISH), and immunohistochemistry (IHC) were used for the detection of parvovirus B19 infection. Sera were tested for B19-specific immunoglobulin M (IgM) and/or IgG using an enzyme-linked immunosorbent assay technique. Based on serology, 149 cases not related to B19 infection were excluded from further analysis. Two of the remaining 124 cases (0.7% of all 273 cases) had parvovirus B19-specific IgM and IgG at the time of abortion, indicating a recent maternal parvovirus B19 infection. In our histological examination, 10 cases contained nuclear vacuolization in fetal erythroid progenitor cells, either in fetal tissues (n = 2) or in placental tissue (n = 8). However, this vacuolization was considered a fixation artifact and not identical to parvovirus B19-specific nuclear inclusions described in previous reports. Only 1 of these 10 cases had parvovirus B19 DNA detectable in placental tissue by PCR analysis. Neither in this case nor in any of the other cases tested was parvovirus B19 DNA or protein detectable by ISH or IHC, respectively. In none of 41 cases in which fetal tissues were available were congenital anomalies found. In conclusion, the frequency of maternal parvovirus B19 infection in this series of fetal losses is low (0.8%). This low frequency does not allow any conclusions with regard to the occurrence of congenital anomalies resulting from parvovirus B19 infection and the usage of nuclear histology for the detection of fetal parvovirus B19 infection is considered a nonspecific parameter that requires confirmation by PCR.

Antibodies, Viral↗

Unusual bone marrow manifestations of parvovirus B19 infection in immunocompromised patients.

Parvovirus B19 is responsible for a spectrum of disease in humans. The usual bone marrow findings in acute parvovirus infections are marked erythroid hypoplasia and occasional giant erythroblasts. Intranuclear inclusions in developing erythroid precursors are rarely described in children or adults with parvovirus infection, although abundant intranuclear inclusions are commonly observed in the placenta and other tissues in infected fetuses. In this study, 8 patients are reported in whom the first evidence of parvovirus infection was the recognition of numerous intranuclear inclusions in erythroid precursors on bone marrow biopsy sections. Six of the 8 patients had documented immunodeficiencies; 4 had acquired immune deficiency syndrome (AIDS), and 2 were on chemotherapy. Five of 7 patients were negative for immunoglobulin G (IgG) antiparvovirus antibodies, including all 4 with AIDS. Unlike the typical pattern in parvovirus infection, the bone marrow was hypercellular in most of the patients, and erythroid precursors were usually increased with the entire spectrum of normoblast maturation represented; abundant intranuclear inclusions were observed similar to the finding in fetuses. The inclusions were variably eosinophilic and compressed the chromatin against the nuclear membrane. In situ hybridization showed parvovirus B19 DNA in numerous erythroid precursors in all cases. The findings of erythroid maturation and abundant viral inclusions in these immunocompromised patients is consistent with the hypothesis that failure to produce effective IgG parvovirus neutralizing antibodies may lead to persistent infection through viral tolerance that allows erythroid development of infected cells past the pronormoblast stage. Identification of parvovirus inclusions in marrow biopsies and subsequent confirmation of infection by in situ hybridization can be important in the assessment of anemia in immunodeficient patients because serological studies for parvovirus B19 are frequently negative.

Acquired Immunodeficiency Syndrome↗

Frequency of human parvovirus B19 infection in intrauterine fetal death.

BACKGROUND: Parvovirus B19 is known to cause fetal death in the second trimester, mainly in combination with hydrops fetalis. However, the frequency of parvovirus-B19-associated non-hydropic fetal loss in the late second and third trimester has not been thoroughly investigated. We aimed to investigate the frequency of parvovirus B19 infection in unselected cases of intrauterine fetal death and to assess the sensitivity of different diagnostic procedures. METHODS: Of 14147 deliveries in three hospitals in the major Stockholm area of Sweden, all cases of intrauterine fetal death (>22 gestational weeks) that occurred between January, 1998, and May, 1999 (n=47), referred cases of miscarriage (<22 gestational weeks, n=37), and induced abortions (n=29), were included in the study. Placental and fetal tissues were examined by means of parvovirus-B19-specific PCR, histopathology, and immunohistochemistry. Placental tissues from 53 normal pregnancies at term were also examined. FINDINGS: Significantly more cases of intrauterine fetal death were positive for parvovirus B19 DNA (seven [15%]) than were normal pregnancies at term (zero, p=0.049). Furthermore, parvovirus B19 DNA was found in two (5%) of the miscarriages but not in any of the cases of induced abortion. Only three of nine DNA-positive cases had parvovirus-B19-associated inclusions and stained positive for viral proteins. All but one of the DNA-positive cases of intrauterine fetal death were non-hydropic. INTERPRETATION: The presence of parvovirus B19 DNA in cases of late second-trimester and third-trimester fetal death is common, and most are non-hydropic. The sensitivity of conventional diagnostic procedures for intrauterine fetal death could be greatly improved by addition of parvovirus B19 PCR.

Adult↗

Parvovirus B19 in the acute arthropathies and juvenile rheumatoid arthritis.

OBJECTIVE: To evaluate the prevalence of recent parvovirus B19 infection in a cohort of children presenting with acute arthropathy and to determine the prevalence of a subsequent diagnosis of juvenile rheumatoid arthritis in this cohort. METHOD: In this prospective study, parvovirus B19 IgM antibody was investigated in 75 patients who were referred to our clinic with acute joint complaints and also in 75 healthy controls. One patient in each group was excluded due to neuroblastoma and acute lymphoblastic leukaemia. The characteristics of parvovirus B19 IgM positive patients who were accepted as parvovirus B19 arthropathy were further evaluated. All the patients were followed up for at least 6 weeks and the patients with chronic progression of joint complaints were followed for at least 6 months to determine their progress. The cases of juvenile rheumatoid arthritis in this chronic group were identified. RESULTS: Parvovirus B19 IgM was detected in 16 of 74 patients (21.6%) with acute arthropathy compared with 3 of 74 (4.1%) in the healthy control group (chi(2) = 8.67; P = 0.003). The parvovirus B19 positive patients with arthropathy were more likely to become chronic (P = 3.7 x 10(-7)) and to be diagnosed as juvenile rheumatoid arthritis (P = 0.03) than the parvovirus B19 IgM negative group with arthropathy. Additional joint destruction developed in one case who was parvovirus B19 IgM positive in whom juvenile rheumatoid arthritis was diagnosed during follow up. CONCLUSION: These data support the hypothesis that parvovirus B19 infection may be associated with the onset of juvenile rheumatoid arthritis in a proportion of patients.

Acute Disease↗

[Diagnostic and therapy of a severe fetal parvovirus-B19-infection with persistence of viral DNA in the mothers blood but inconspicuous serological tests. Case report].

In the 24th week of gestation we diagnosed a severe hydrops fetalis in a 25 year old VI gravid III para, who had contact to parvovirus B19 in the 14th week of gestation. Because of the severe anaemia of the fetus and the massively increased bilirubinoides in the amniotic fluid we decided at the same day to apply the first of four intrauterine transfusions. The serological patterns of maternal blood with highly positive parvovirus-B19-IgG and negative IgM suggested that an infection had occurred. Parvoviral DNA was found in maternal and fetal blood confirming the diagnosis of an acute intrauterine parvovirus-B19 infection. No viral DNA was detected in fetal ascites. IgM in fetal blood was negative. By means of four transfusions, the pregnancy could be prolonged until the 32 + 5th week of gestation while the ascites was declining. When rupture of membranes occurred, a cesarean section had to be performed due to contractions and presentation of the feet. The newborn's blood count exhibited a thrombocytopenia with normal haemoglobin and haematocrit. Five days after delivery, a blood exchange had to be done because of a hyperbilirubinaemia. After seven weeks, the child could be dismissed from hospital in good general status, with decreasing ascites, normal liver function and normal neurological status. The blood of the newborn was tested to be positive for IgG, while IgM-antibodies and parvovirus-B19-DNA were negative. The diagnosis of a parvovirus-B19 infection of a fetus with severe hydrops and anaemia could be verified by a positive proof for DNA in maternal blood, with negative IgM and highly positive parvovirus-B19-IgG and on the other hand highly positive viral DNA in fetal blood and in the amniotic fluid. 10 weeks after contact to parvovirus B19, i. e. in the 24th week of gestation, positive IgG- and negative IgM-antibodies were found in the mother's blood, whereas fetal complications were noticed. These data demonstrate that following an acute parvovirus-B19-infection of the mother IgM-antibodies can be proofed for 6 - 8 (- 10) weeks. On the other side parvovirus-B19-DNA in the mothers blood is detectable by means of PCR for 8 - 10 weeks and in some cases even more than 15 weeks.

Adult↗

An assay for parvovirus B19 neutralizing antibodies based on human hepatocarcinoma cell lines.

BACKGROUND: Although intravenous immune globulin (IVIG) is used widely for managing parvovirus B19 infections, IVIG products are not monitored routinely for the presence of parvovirus B19 neutralizing antibody. STUDY DESIGN AND METHODS: An assay has been developed to measure parvovirus B19 infectivity and neutralization activity based on two hepatocarcinoma cell lines (HepG2 and HuH7). The sources of parvovirus B19 were B19-DNA-containing plasma samples. Neosynthesized progeny in supernatants of infected cells were quantified by nested polymerase chain reaction. To validate the model, purified rabbit antibodies to different capsid protein sequences and IVIG preparations were tested. RESULTS: The number of parvovirus B19 infectious neovirions in supernatants of infected cells increased with infection time. Both rabbit antibodies and IVIG products inhibited parvovirus B19 infectivity when incubated overnight with virus. The efficacy of IVIG to neutralized parvovirus B19 was product-related. CONCLUSION: This assay for parvovirus B19 neutralization activity provides an improved and more specific method for selecting donors to produce IVIG with a high titer of parvovirus B19 neutralizing activity.

Animals↗

Seroprevalence, incidence of prenatal infections and reliability of maternal history of varicella zoster virus, cytomegalovirus, herpes simplex virus and parvovirus B19 infection in South-Western Finland.

OBJECTIVE: To study seroprevalence and incidence and fetal transmission of varicella zoster virus (VZV), cytomegalovirus (CMV), herpes simplex virus (HSV) types 1 and 2 and parvovirus B19 infections during pregnancy and to evaluate the reliability of maternal past history of VZV, HSV and parvovirus infections. DESIGN: Prospective study of parturient women. SETTING: South-Western Finland. PARTICIPANTS: Five hundred and fifty-eight parturient women. METHODS: IgG and IgM antibodies against VZV, CMV, HSV-1 and -2, and parvovirus B19 were measured from maternal serum in the first trimester and at delivery and from cord serum, mother's own information of her past infections was compared with her serological status. MAIN OUTCOME MEASURES: Seroprevalence, seroconversions and fetal transmission of VZV, CMV, HSV and parvovirus B19, reliability of maternal history of VZV, HSV and parvovirus B19. RESULTS: Seroprevalences were 96.2% for VZV, 56.3% for CMV, 54.3% for HSV, 46.8% for HSV-1, 9.3% for HSV-2 and 58.6% for parvovirus B19. Parity was associated with CMV seropositivity, maternal age differed only between HSV-2 seropositive and seronegative women, while area of residence (urban or rural) had no effect. Six seroconversions were observed: two VZV, one CMV and three parvovirus infections. No cases of primary HSV infections occurred. Fetal transmission was observed in two cases of parvovirus infection. No infants with anti-CMV IgM antibodies were born to CMV immunised women. False positive history of chickenpox was given only by 1.5% of the women, history of herpes infections was less reliable, and history of parvovirus infection was unreliable. CONCLUSIONS: Seroprevalence and the risk of viral infections during pregnancy cannot be extrapolated from one pregnant population to another.

Adolescent↗

Molecular and structural basis of the evolution of parvovirus tropism.

Parvoviruses have small genomes and, consequently, are highly dependent on their host for various functions in their reproduction. Since these viruses generally use ubiquitous receptors, restrictions are usually intracellularly regulated. A lack of mitosis, and hence absence of enzymes required for DNA replication, is a powerful block of virus infection. Allotropic determinants have been identified for several parvoviruses: porcine parvovirus, canine parvovirus (CPV), feline parvovirus (feline panleukopenia virus), minute virus of mice, Aleutian disease virus, and GmDNV (an insect parvovirus). Invariably, these identifications involved the use of infectious clones of these viruses and the exchange of restriction fragments to create chimeric viruses, of which the resulting phenotype was then established by transfection in appropriate cell lines. The tropism of these viruses was found to be governed by minimal changes in the sequence of the capsid proteins and, often, only 2 or 3 critical amino acids are responsible for a given tropism. These amino acids are usually located on the outside of the capsid near or on the spike of the threefold axis for the vertebrate parvoviruses and on loops 2 or 3 for the insect parvoviruses. This tropism is not mediated via specific cellular receptors but by interactions with intracellular factors. The nature of these factors is unknown but most data point to a stage beyond the conversion of the single-stranded DNA genome by host cell DNA polymerase into monomeric duplex intermediates of the replicative form. The sudden and devastating emergence of mink enteritis virus (MEV) and CPV in the last 50 years, and the possibility of more future outbreaks, demonstrates the importance of understanding parvovirus tropism.

Animals↗

[Congenital aplastic anemia caused by parvovirus B19 infection].

Human parvovirus B19 causes the fifth disease (erythema infectiosum) in childhood. Intrauterine infection by parvovirus in immunocompromised fetus can lead to the severe congenital aplastic anemia. Here we report the case of 2.5-year-old girl with congenital infection with parvovirus B19. The girl was born as a pre-term baby with hydrops, congenital aplastic anemia, and low level of immunoglobulins IgG and IgM. She depended on the repeated blood transfusions and she did not respond to erythropoietin therapy. The parvovirus B19 infection in bone marrow was detected by polymerase chain reaction and its therapy started with intravenous administration of immunoglobulins. Hemoglobin reached normal level one year later, but low levels of parvovirus B19 were detectable for another 6 months. Immunoglobulin treatment was finished when the virus could not be detected in the circulation. However, one-month later parvovirus B19 DNA was detected again. The two months course of immunoglobulin treatment was repeated, and the DNA analysis of blood cells for parvovirus B19 has been negative since then. Five months after the final withdrawal of the immunoglobulin therapy the girl is in a good shape and all lab tests, except for the decreased levels of IgM, are within the normal range. The PCR monitoring of the presence of parvovirus B19 DNA in blood and bone marrow cells during and after the treatment of congenital aplastic anemia caused by parvovirus B19 chronic infection becomes the necessity for the rational therapy.

DNA, Viral↗

Detection of rodent parvoviruses by use of fluorogenic nuclease polymerase chain reaction assays.

Polymerase chain reaction (PCR) assays have proven useful for detection of rodent parvoviruses in animals and contaminated biological materials. Fluorogenic nuclease PCR assays combine PCR with an internal fluorogenic hybridization probe, eliminating post-PCR processing and potentially enhancing specificity. Consequently, three fluorogenic nuclease PCR assays were developed, one that detects all rodent parvoviruses, one that specifically detects minute virus of mice (MVM), and one that specifically detects mouse parvovirus 1 (MPV) and hamster parvovirus (HaPV). When rodent parvoviruses and other rodent DNA viruses were evaluated, the rodent parvovirus assay detected only rodent parvovirus isolates, whereas the MVM and MPV/HaPV assays detected only the MVM or MPV/ HaPV isolates, respectively. Each assay detected the equivalent of 10 or fewer copies of target template, and all fluorogenic nuclease PCR assays exceeded the sensitivities associated with previously reported PCR assays and mouse antibody production testing. In addition, each fluorogenic nuclease PCR assay detected the targeted parvovirus DNA in tissues obtained from mice experimentally infected with MVM or MPV. Results of these studies indicate that fluorogenic nuclease PCR assays provide a potentially high-throughput, PCR-based method to detect rodent parvoviruses in infected mice and contaminated biological materials.

Animals↗