The magnitude and correlates of Parvovirus B19 infection among pregnant women attending antenatal clinics in Mwanza, Tanzania

Seroinfection of Antibodies to Toxoplasma gondii, Parvovirus B19, Treponema pallidum, and HIV in a Pregnant Attending a Medical Center in Northern Peru

Introduction

Transplacental infections are frequent, especially in developing countries, where limited screening is performed to find infectious agents in the pregnant population. We aim to determine the clinical and epidemiological characteristics and seroinfection of antibodies against Toxoplasma, parvovirus B19, T. pallidum, and HIV in pregnant women who attended the Motupe Health Center in Lambayeque, Peru during July-August 2018.

Methods

A descriptive cross-sectional study was conducted in 179 pregnant women interviewed with a standardized questionnaire. ELISA was used to determine antibodies to Toxoplasma and parvovirus B19. The detection of syphilis and HIV was conducted using immunochromatography, while the detection of hepatitis B was conducted using FTA-ABS and immunofluorescence, respectively.

Results

Of 179 pregnant women, syphilis and HIV infections routinely included in the screening of pregnant women presented a seroinfection of 2.2 and 0.6%, respectively. Toxoplasmosis seroinfection was 25.1%, while IgM antiparvovirus B19 was 40.8%, revealing that pregnant women had an active infection at the time of study.

Conclusion

The level of seroinfection of toxoplasmosis reveals the risk to which pregnant women who participated in the study are exposed. The high seroinfection of parvovirus B19 could explain the cases of spontaneous abortion and levels of anemia in newborn that have been reported in Motupe, Lambayeque, Peru. However, future causality studies are necessary to determine the significance of these findings.

Prevalence of parvovirus B19 antibodies in pregnant women in northern Benin

OBJECTIVES

Parvovirus B19 (B19V) infection in pregnancy is generally asymptomatic, but in about 3% it can cause complications, including miscarriage, severe foetal anaemia and foetal hydrops. The seroprevalence in pregnancy ranges from 20% to 82% in Africa, but there are no data for Benin. We therefore retrospectively assessed the seroprevalence of B19V in pregnant women attending the Saint Jean de Dieu Hospital in Tanguiéta, a rural district of Atacora, in northern Benin.

METHODS

We searched for anti-B19V immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies in 227 sequential sera from as many women (mean age 26.3 years, range: 16-41) of whom 30 were in the first trimester, 66 in the second and 131 in the third. Samples that tested positive for IgM were analysed with an immunoblot test and the viral genome (DNA-B19V) was searched for using a polymerase chain reaction.

RESULTS

Of the 227 women, 153 (67.4%) were positive for IgG anti-B19V, 7 (3.1%) for IgM and 73 (32.2%) were non-immune. Six IgM-positive women were also IgG positive. The difference in IgG seroprevalence between trimesters or ages was not statistically significant. Of the seven IgM-positive samples, three were confirmed positive by immunoblot (of which two were DNA-B19V positive), three were indeterminate (DNA-B19V negative) and one was negative (DNA-B19V negative). Of the three women with confirmed positive IgM, two were in the third trimester and one in the second trimester of pregnancy.

CONCLUSIONS

The seroprevalence of anti-B19V IgG among pregnant women in Benin is high and in line with those reported in some African countries. IgM seroprevalence is also similar to that described in some African countries in non-epidemic periods. The low viral load observed depicts non-acute infections, but it is difficult to establish the precise time of the infection, especially for women tested in the second or third trimester of pregnancy, when the observed viremia could be a sign of an acute infection that occurred in the previous trimester. Consequently, clinical follow-up and further investigations to highlight possible foetal consequences are indicated.

Herpes Simplex Virus Type 2 (HSV-2) and Cytomegalovirus (CMV) among Women with Macerated Stillbirth: A Cross-Sectional Hospital-Based Study from Mwanza, Tanzania

Background

Stillbirth adversely affects pregnancy outcomes in low- and middle-income countries (LMICs). Viral infections have been implicated as one of the causes of stillbirths. Despite high rates of stillbirths and high viral prevalence in LMICs, there is limited information regarding their association. This study investigated the magnitude of herpes simplex 2 virus (HSV-2) and human cytomegalovirus (HCMV) among women with macerated stillbirth.

Methods

A cross-sectional hospital-based study was conducted involving 279 women with macerated stillbirth between July and August 2018 at different health facilities in Mwanza, Tanzania. Detection of HSV-2 was done by immunochromatographic test while that of HCMV was done using enzyme-linked immunosorbent assay (ELISA). Descriptive data analysis was done using STATA version 13.

Results

A total of 28 (10.04%, 95% CI: 6.8-13.9) tested positive for HSV-2 IgG antibodies with only 4 (1.43%, 95% CL: 0.3-2.8) testing positive for HSV-2 IgM antibodies. HCMV IgG antibodies were detected in 131 (77.98%, 95% CI: 71-84) of 168 women tested. By multivariate logistic regulation analysis, advanced age (OR: 0.93, 95% CI: 0.87-0.99, p = 0.025) was significantly associated with negative HSV-2 IgG antibodies. By log multinomial regression analysis, only urban residence (RRR.4.43: 95% CI 1.53-12.80, p = 0.006) independently predicted HCMV IgG seropositivity among women with stillbirth. Twenty-one (30.9%) of women with positive HCMV IgG antibodies had low avidity index (<40%) indicating recent infection.

Conclusion

Significant proportion of women with macerated stillbirth residing in urban and with low age have HCMV and HSV antibodies, respectively. This calls for the need to consider introducing screening of these infections in the Tanzanian antenatal package and further studies to explore the role of these viruses in causing stillbirth in Tanzania.

Parvovirus (B19) Infection during Pregnancy: Possible Effect on the Course of Pregnancy and Rare Fetal Outcomes. A Case Report and Literature Review

Infection caused by human parvovirus B19 (B19) often has mild yet wide-ranging clinical signs, with the course of disease usually defined as benign. Particularly prevalent in the population of young children, the virus is commonly transmitted to the parents, especially to susceptible mothers. During pregnancy, particularly the first and second trimesters, parvovirus infection can lead to pathology of the fetus: anemia, heart failure, hydrops, and disorders of physical and neurological development. In severe cases, the disease can result in fetal demise. This article presents a rare case of manifestation of B19 infection during pregnancy. At the 27th week of gestation, a sudden change in fetal movement occurred in a previously healthy pregnancy. The examination of both fetus and the mother revealed newly formed fetal subdural hematoma of unknown etiology and ventriculomegaly. Following extensive examination to ascertain the origin of fetal pathology, a maternal B19 infection was detected. Due to worsening fetal condition, a planned cesarean section was performed to terminate the pregnancy at 31 weeks of gestation. A preterm male newborn was delivered in a critical condition with congenital B19 infection, hydrocephalus, and severe progressive encephalopathy. The manifestation and the origin of the fetal condition remain partially unclear. The transplacental transmission of maternal B19 infection to the fetus occurs in approximately 30% of cases. The main method for diagnosing B19 infection is Polymerase Chain Reaction (PCR) performed on blood serum. In the absence of clinical manifestations, the early diagnosis of B19 infection is rarely achieved. As a result, the disease left untreated can progress inconspicuously and cause serious complications. Treatment strategies are limited and depend on the condition of the pregnant woman and the fetus. When applicable, intrauterine blood transfusion reduces the risk of fetal mortality. It is crucial to assess the predisposing factors of the infection and evaluate signs of early manifestation, as this may help prevent the progression and poor outcomes of the disease.

Molecular Evaluation of Human Parvovirus B19 Infection and Associated Risk Factors among Pregnant Women in Bushehr Province, Southern Iran

Given the importance of human parvovirus B19 infection during pregnancy and the potential risks to the fetus, this study was designed to determine the prevalence, genotypic pattern, and risk factors of parvovirus B19 infection among a population-based sample of pregnant women in Bushehr Province, southern Iran. A total of 824 pregnant women were enrolled in this study. Serum samples were screened for the detection of anti-parvovirus B19 IgM and IgG by ELISA. The molecular evaluation was performed by nested polymerase chain reaction, targeting the non-structural protein 1-viral protein 1 unique region of the genome, and sequencing. Of 824 pregnant women, 330 (40.1%) were positive for anti-parvovirus B19 IgG and 50 women (6.1%) had anti-parvovirus B19 IgM. A greater rate of anti-parvovirus B19 IgG seroprevalence was observed in women older than 39 years, in Afghan immigrants, and in those women with more parities. Anti-parvovirus B19 IgM seroprevalence decreased with increasing gestational age and was significantly greater among women in the first trimester of pregnancy and among residents of the city of Borazjan. Moreover, 0.73% of the pregnant women had parvovirus B19 viremia with genotype 1 and subtype 1a. Parvovirus B19 DNA was detected in the samples collected in late autumn and winter, which is a rainy season associated with temperate climes in southern Iran. According to the results of this study, approximately 60% of pregnant women in this region are serologically negative and susceptible to parvovirus B19 infection. Therefore, assessment for maternal parvovirus B19 infection is important and should be considered as part of the fetal-maternal health policy in Iran.

Serological Markers of Viral Infections (Rubella Virus, Human Cytomegalovirus and Arboviruses) among Symptomatic Pregnant Women in Rural and Urban Areas of Mwanza, Tanzania

Viral infections have been associated with poor pregnancy outcomes. We investigated the magnitude of rubella virus (RV), dengue virus (DENV), Zika virus (ZIKV) and human cytomegalovirus (HCMV) among symptomatic pregnant women in rural and urban areas of Mwanza. A cross-sectional study was conducted between July 2017 and April 2018 in Mwanza. A rapid immunochromatographic test was done to detect ZIKV IgM and IgG as well as DENV IgM and IgG antibodies. A multiplex_RT-PCR was also done to detect the viral RNA genome. Enzyme immunoassays were done to detect RV and HCMV. Out of 171 participants, 1 (0.6%) was found to be seropositive for ZIKV_IgM antibodies, while 5 (2.9%) were ZIKV_IgG seropositive. DENV seropositivity was 9 (5.3%) and 3 (1.8%) for IgM and IgG, respectively, with all being PCR negative. Two participants (1.2%) were RV_IgM seropositive. 100% were HCMV_IgG seropositive and none was HCMV_IgM seropositive. Among 70 women with high HCMV_IgG titters, 10 (14.3%) had a low avidity index, indicating recent infections. Residing in rural areas (p = 0.044) and advanced age (p = 0.024) independently predicted ZIKV/DENV seropositivity. A substantial proportion of pregnant women had markers for viral infections. There is a need for introducing routine screening and monitoring pregnancy outcomes of positive cases to establish the relationship of these viruses and adverse pregnancy outcomes in endemic areas.

Parvovirus B19 Seroprevalence in Women with Bad Obstetric History in Kirkuk

BACKGROUND

In Iraqi community, abnormal pregnancy form a major social ans psychological and health problem. The underlying etiology of this health phenomenon was varied and includes sets of infections and autoimmune diseases. Globally human parvovirus 19 infection is common and the infection attribute to bad obstetric outcomes. Global maternal parvovirus B19 remote infection rate was with a range of 13.2% to 97.9%, while the range of acute infection was 0.5% to 97.9%. In Arab countries, the IgG seroprevalence was 53.3% to 74%, while IgM seroprevalence range was 2.2% to 84%.

OBJECTIVE

To evaluate the role of Parvovirus B19 as an etiology of bad obstetric outcome in women in Kirkuk, Iraq.

MATERIALS AND METHODS

Descriptive Case Control Study. Women included in the study were recruited from Kirkuk General Hospital and their age ranged from 14 to 48 years. A 663 women were included in the study and 237 of them were none pregnant, while the pregnant were 215. Additionally, the study included 211 women with inevitable abortion. A control group (306 women) women with history of normal pregnancy (Pregnant=149; non-pregnant=157). Clinical and laboratory investigations were conducted on all patients and control groups to exclude other causes [7]. Medical and obstetric data and demographic characteristics gathered through interview according to previously designed questionnaire [7]. ELISA kits were used to determine Parvovirus B19 IgM and IgG antibodies.

RESULTS

The overall parvovirus seroprevalence was 93% and with no significant difference between women with normal (89.5%) and those with abnormal (93.1%) pregnancy outcomes . In addition, parvovirus IgM overall seroprevalence was 56.3%. Furthermore, current parvovirus infection was higher in women with BOH (52.6%) than that in women with normal pregnancy (49.7%) outcomes. Parvovirus IgM seroprevalence was 52.6% in women with BOH and 49.7% in women with normal pregnancy, however, the difference was not statistically significant. In contrast, the acute infection with parvovirus was significantly (X2=11.8, P=0.001) lower in women with normal pregnancy (49.7%) than in those with inevitable abortion (64.9%), While IgG seroprevalence difference was not significant between the two groups. Infection seroprevalence was more frequent in housewife, uneducated women, large family size, non-smoker, rural area, non animal exposure, repeated abortion, congenital anomalies, and anaemia.

CONCLUSION

Parvovirus B19 infection may be with bad obstetric outcomes if occurred during pregnancy and OR confirm a significant association of the infection with parvovirus with smoking, occupation, crowding index, education, animal exposure and number of repeated abortion.

PREVALENCE OF HUMAN PARVOVIRUS B19 IgG AND IgM ANTIBODIES AMONG PREGNANT WOMEN ATTENDING ANTENATAL CLINIC AT FEDERAL TEACHING HOSPITAL IDO-EKITI, NIGERIA

Background:

Human Parvovirus B19 (B19V) is a DNA virus, transmitted through respiratory secretions, hand-to-mouth-contact, blood transfusion and trans-placental transfer. It causes high mortality and morbidity in pregnant women, thus contributing to poor maternal and child health. B19V has been neglected due to dearth of epidemiological data. The aim of this study was to determine the sero-prevalence of Human Parvovirus B19 antibodies among pregnant women attending antenatal clinic at Federal Teaching Hospital Ido-Ekiti, Nigeria.

Materials and Methods:

This cross-sectional study enrolled pregnant women attending Federal Teaching Hospital Ido-Ekiti from January to May 2019 to obtain sero-epidemiological data. One hundred and twenty-two (122) consenting pregnant women were enrolled following institutional ethical approval. They were administered structured questionnaire and venous blood was collected in plain tubes for serum extraction. Sera samples were analyzed for IgG and IgM antibodies using the enzyme linked immunosorbent assay method. Percentages, median, chi-square and multivariate analysis were carried out using SPSS version 17.

Results:

The prevalence of IgG was 44.3% (54/122), IgM 41.8% (51/122), and IgG/IgM 28.7% (35/122) leaving 55.7% (68/122) of the population uninfected. The median age of participants was 22 (Interquartile range 18-25) years among which 36-45years had the highest prevalence which was not statistically significant (p=0.09 X² =4.75). There was association between miscarriage, still birth, history of blood transfusion and prevalence of Human Parvovirus B19 (p<0.05).

Conclusion:

There is a high Prevalence of B19V among pregnant women attending antenatal clinic in this study. This underscores the need for testing and immunization of pregnant women against B19V.

Seroprevalences of antibodies against ToRCH infectious pathogens in women of childbearing age residing in Brazil, Mexico, Germany, Poland, Turkey and China

Determination of antibodies against ToRCH antigens at the beginning of pregnancy allows assessment of both the maternal immune status and the risks to an adverse pregnancy outcome. Age-standardised seroprevalences were determined in sera from 1009 women of childbearing age residing in Mexico, Brazil, Germany, Poland, Turkey or China using a multiparametric immunoblot containing antigen substrates for antibodies against Toxoplasma gondii, rubella virus, cytomegalovirus (CMV), herpes simplex viruses (HSV-1, HSV-2), Bordetella pertussis, Chlamydia trachomatis, parvovirus B19, Treponema pallidum and varicella zoster virus (VZV). Seroprevalences for antibodies against HSV-1 were >90% in samples from Brazil and Turkey, whereas the other four countries showed lower mean age-adjusted seroprevalences (range: 62.5-87.9%). Samples from Brazilian women showed elevated seroprevalences of antibodies against HSV-2 (40.1%), C. trachomatis (46.8%) and B. pertussis (56.6%) compared to the other five countries. Seroprevalences of anti-T. gondii antibodies (0.5%) and anti-parvovirus B19 antibodies (7.5%) were low in samples from Chinese women, compared to the other five countries. Samples from German women revealed a low age-standardised seroprevalence of anti-CMV antibodies (28.8%) compared to the other five countries. These global differences in immune status of women in childbearing age advocate country-specific prophylaxis strategies to avoid infection with ToRCH pathogens.

Parvovirus B19 Is Associated with a Significant Decrease in Hemoglobin Level among Children <5 Years of Age with Anemia in Northwestern Tanzania

Parvovirus B19 (B19) can cause transient aplastic crisis and lead to acute severe anemia. This study investigated the relationship between B19 and anemia among children <5 years old in the city of Mwanza, Tanzania. An enzyme immunoassay was used to detect B19 IgM- and IgG-specific antibodies among children with various categories of anemia according to the World Health Organization (WHO) guidelines. A total of 265 children with median age of 28.5 months (interquartile range 18-39.5) were investigated. Eighty-six children (32.5%) had severe anemia. B19-specific IgM and IgG antibodies were detected in 24 (9%) and 46 (17.4%) children, respectively. Low hemoglobin (Hb) level (p = 0.031), Plasmodium falciparum infection (p = 0.001) and residing in rural areas (p = 0.025) independently predicted B19 IgM seropositivity. Acute B19 infection decreased Hb level by 1.1 g/dl (p = 0.003). In malaria endemic areas, acute B19 infections should be considered among children with severe anemia from rural areas.

Congenital cytomegalovirus, parvovirus and enterovirus infection in Mozambican newborns at birth: A cross-sectional survey

Background

Congenital cytomegalovirus (cCMV) infection is the most prevalent congenital infection acquired worldwide, with higher incidence in developing countries and among HIV-exposed children. Less is known regarding vertical transmission of parvovirus B19 (B19V) and enterovirus (EV). We aimed to assess the prevalence of CMV, B19V and EV vertical transmission and compare results of screening of congenital CMV obtained from two different specimens in a semirural Mozambican maternity.

Methods

A cross sectional study was conducted among pregnant mothers attending Manhiça District Hospital upon delivery. Information on maternal risk factors was ascertained. Dried umbilical cord (DUC) samples were collected in filter paper for CMV, B19V and EV detection by real-time polymerase chain reaction (RT-PCR), and nasopharyngeal aspirates (NPA) to test for CMV by RT-PCR. Maternal blood samples and placental biopsy samples were also obtained to investigate CMV maternal serology, HIV status and immunopathology.

Results

From September 2014 to January 2015, 118 mothers/newborn pairs were recruited. Prevalence of maternal HIV infection was 31.4% (37/118). CMV RT-PCR was positive in 3/115 (2.6%) of DUC samples and in 3/96 (6.3%) of NPA samples obtained from neonates. The concordance of the RT-PCR assay through DUC with their correspondent NPA sample was moderate (Kappa = 0.42 and p<0.001. No differences on cCMV prevalence were found among HIV-exposed and unexposed. All (100%) mothers were seropositive for CMV IgG. RT-PCR of EV and B19V in DUC were both negative in all screened cases. No histological specific findings were found in placental tissues. No risk factors associated to vertical transmission of these viral infections were found.

Conclusions

This study indicates the significant occurrence of vertical transmission of CMV in southern Mozambique. Larger studies are needed to evaluate the true burden, clinical relevance and consequences of congenital infections with such pathogens in resource-constrained settings.

Rubella natural immunity among adolescent girls in Tanzania: the need to vaccinate child bearing aged women

BACKGROUND

Rubella primary infection during early stages of pregnancy is associated with high risk of congenital Rubella syndrome (CRS). Prevention of CRS in the resource-limited countries requires multiple strategies. Here, we document the data on the magnitude of Rubella natural immunity among adolescent girls which is a crucial group in devising effective control strategies to prevent CRS.

METHODS

A cross sectional study involving 397 adolescent girls was conducted in the city of Mwanza involving five secondary schools. Socio-demographic and other relevant information were collected using pre-tested data collection tool. Rubella IgG antibodies were determined using enzyme immunoassay. The presence of Rubella IgG titers of >10 IU/ml indicated natural immunity.

RESULTS

The mean age of the study participants was 15.18 ± 1.48 years. Of 397 girls, 340 (85.6%) and 57 (14.4%) were from secondary schools representing peri-urban and rural areas, respectively. Out of 397 girls, 90.4% (95% CI: 87-93) were found to be naturally immune with median Rubella IgG antibodies titers of 56.7 IU/ml interquartile range (IQR): 40.8-137. The median Rubella IgG antibodies titers were significantly high in adolescent girls from families with high socio-economic status (63.96 vs. 47.13 IU/ml, P < 0.001) and in adolescent girls from peri-urban areas of the city (63.33 vs. 39.9 IU/ml, P < 0.001).

CONCLUSION

The majority of adolescent girls in the city of Mwanza are naturally immune to Rubella virus. There is a need to compare the effectiveness of screening and vaccinating susceptible adolescent girls with the effectiveness of vaccinating all women of childbearing in controlling CRS in low-income countries.

Parvovirus B19 infection in pregnancy-awareness and opportunities

Parvovirus B19 (B19V) is a human pathogenic virus associated with a wide range of clinical conditions. In pregnancy, B19V poses a potential hazard to the fetus as crossing the placental barrier and infecting erythroid progenitor cells in bone marrow and liver, it blocks fetal erythropoiesis leading to profound anemia, hydrops and/or fetal death. The virus is not regarded as a teratogen, however more scientific awareness is emerging on mechanisms and consequences of intrauterine infection and possible sequelae in the neonatal development. Reliable diagnostic procedures and fetal management strategies, including intrauterine transfusion, are established. In spite of being a recognized fetotropic agent possibly leading to fetal loss, testing for B19V is not routinely included in preconception or antenatal screenings, possibly delaying the management of B19V-complicated pregnancies. Continuous advances in B19V research will provide for better diagnostic methods and algorithms, as well as for the development of effective prophylactic interventions and novel therapeutic options.