Antibodies In Pregnant Women Research Articles

Transplacental transfer of Lassa IgG antibodies in pregnant women in Southern Nigeria: A prospective hospital-based cohort study.

Evidence from previous studies suggest that Lassa fever, a viral haemorrhagic fever endemic to West Africa has high case fatalities, particularly in pregnancy. While there have been remarkable innovations in vaccine development, with some Lassa vaccines undergoing early clinical trials. An understanding of Lassa antibody kinetics and immune responses will support vaccine design and development. However, there is currently no evidence on the antibody kinetics of Lassa (LASV) in pregnancy. Our study sought to estimate the efficiency of transplacental transfer of LASV IgG antibodies from the mother to the child. The study made use of data from a prospective hospital-based cohort of pregnant women enrolled at the antenatal clinic and followed up at delivery between February and December 2019. Blood samples from mother-child pairs were evaluated for antibodies against Lassa virus. The study demonstrates a transplacental transfer of LASV IgG of 75.3% [60.0-94.0%], with a significant positive correlation between maternal and cord concentrations and a good level of agreement. The study also suggests that transfer may be more variable in women with 'de novo' antibodies compared to those with pre-existing antibodies. The study shows that maternal antibody levels play an important role in determining transfer efficiency of Lassa antibodies to the new-born; and while the evidence is preliminary, the study also suggests that transfer efficiency may be less stable in acute or recent infection, as such timing of vaccination before pregnancy, that is in women of childbearing age may be more appropriate for protection of both pregnant women and their neonates.

Anti-phosphatidylserine antibody levels are low in multigravid pregnant women in a malaria-endemic area in Nigeria, and do not correlate with anti-VAR2CSA antibodies.

Anemia is a common malaria-associated complication in pregnant women in endemic regions. Phosphatidylserine (PS) is exposed to the immune system during the massive destruction of red blood cells (RBCs) that accompany malaria, and antibodies against PS have been linked to anemia through destruction of uninfected RBCs. We determined levels of anti-PS IgG antibodies in pregnant women in Ibadan, Nigeria and correlated them to parameters of importance in development of anemia and immunity. Anti-PS correlated inversely with Packed Cell Volume (PCV), indicating that the antibodies could contribute to anemia. There was no correlation with anti-VAR2CSA IgG, haptoglobin or parasitemia, indicating that the modulation of anti-PS response is multifactorial in nature. Anti-PS levels were lowest in multigravidae compared to both primigravidae and secundigravidae and correlated inversely with age. In conclusion, lower levels of anti-PS in multigravidae could be beneficial in avoiding anemia.

Investigating the Correlation Between HLA-II Gene Polymorphism and RhE Alloimmunization in Pregnant Chinese Women.

The Rhesus (Rh) blood group is a significant and complicated biological system in humans. Incompatible transfusion or pregnancy with Rh antigens can lead to the production of alloantibodies, among which the anti-E antibody is prevalent. The relationship between Anti-E antibody and HLA-II gene polymorphism in Chinese pregnant women is worth exploring. Our aim in this study was to verify the correlation between HLA-II gene polymorphisms and RhE alloimmunization in pregnant Chinese women through HLA-II typing and DR-RhE structural prediction. In total, 94 anti-E-negative pregnant women and 103 anti-E-positive pregnant women were enrolled from Southwest China Second Hospital, and HLA-II genotyping was performed using next-generation sequencing. NetMHCpan software was used to predict the binding of E -derived anchoring peptides to HLA-DRB1 molecules. AlphaFold was used to analyze the differences in antigen presentation based on the structure of major histocompatibility complex peptides. The HLA-DRB1*09:01-DQA1*03:02-DQB1*03:03 haplotype showed a significant positive association with anti-E. One E-derived anchoring peptide (219FWPSVNSPL227) was predicted to bind to the HLA-DRB1*09:01 molecule. The interaction between the 60Ser of DR9 and 226pro of RhE comprised one hydrogen bond. This study demonstrated that HLA-II haplotypes are associated with allo-anti-E antibodies in pregnant women from Sichuan Province, China. The HLA-DRB1*09:01-DQA1*03:02-DQB1*03:03 phenotype may enhance the formation of anti-E alloantibodies, and the HLA-DRB1*09:01 molecule may play a key role in alloimmunity.

Parvovirus B19 in Morocco: Seroprevalence of Immunoglobulin G Antibody in Pregnant Women in Marrakesh

Background: Parvovirus B19 (B19V) infection is ever-present and contagious. It is acquired during childhood and adolescence, but can occur at any age. B19V infection occurs in endemic epidemic mode in temperate zones in winter and spring. B19V infections, although often asymptomatic in pregnant women, can be responsible for hydrop fetalis, fetal anemia, and death in utero. This study will evaluate the seroprevalence of immunoglobulin G (IgG) antiparvovirus in pregnant women in Marrakesh city in Morocco, and to find out the possible risk factors associated with B19V infections. Methods: We randomly selected 100 pregnant women from the Zerktouni hospital in Marrakesh. Socio-demographic characteristics and background were collected using a questionnaire. Serologic tests were carried out by searching for immunoglobulin G antibodies via the ParvovirusVirclia® IgG Chemiluminescencemonotest kits (Vircell Microbiologist, Granada, Spain) at the Bacteriology-Virology laboratory of the Avicenna Military Hospital in Marrakesh. Results: The median age of study participants was 27 (interquartile range (IQR): 17–43) years. Of 100 pregnant women 8%, 38% and 54% were in the first, second and third trimester respectively. The majority 96% of women were from urban areas. Nineteen percent (19%) of them had a history of spontaneous abortion. Of 100 pregnant women, the overall prevalence of IgG was 51 (51%). The average age of participants with positive serology was 26.45 years, and the mean age of those with negative serology was 28.98 years. The immunity against the virus was higher in young pregnant women. Twenty five (25%) women tested positive for B19V antibodies in the third trimester of pregnancy, implying immunity for the virus. The results of logistic regression showed insignificant association between the prevalence of B19V IgG antibodies and the demographic and obstetrical factors except for the having a child under 6 years factor (χ2 = 12.33, p = 0.001). Conclusions: Infection with B19V remains important in pregnant women in our region and virological diagnosis must be sought before any suggestive context.

Prevalence of parvovirus B19 antibodies in pregnant women in northern Benin.

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. 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. 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. 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.

Measles Serostatus in Mothers and Their Newborns in Antioquia, Colombia: Implications for Measles Elimination.

To describe the serostatus of measles IgG antibodies in pregnant women and newborns, placental transfer, and factors that determine being below the threshold of 150 mIU/mL, a cross-sectional study was conducted. Blood samples of 790 pregnant women at the time of delivery and 734 umbilical cord samples were analyzed from eight hospitals in the Aburrá Valley of Antioquia, Colombia. Measles IgG antibody measurement was performed with ELISA. The proportion of individuals with antibodies < 150 mIU/mL was 13.9% (95% CI: 12.2-15.8) in pregnant women and 11.1% (95% CI: 9.2-13.4) in newborns. The geometric mean of the antibody level of the pregnant women was 552 mIU/mL (95% CI: 504-605) and in the umbilical cord 662 mIU/mL (95% CI: 604-727). A positive correlation between pregnant woman and umbilical cord antibodies was found. The median ratio of measles IgG antibodies in umbilical cord/pregnant woman was 1.22 for all participants. A seroprevalence below the threshold of 150 mIU/mL was found in newborns whose mothers were born between 1983 and 1994, compared with those born before that period, when exposure to the wildtype virus was common (adjusted prevalence ratio: 3.6, 95% CI: 1.3-9.6). These findings suggest that there are gaps in measles immunity among women of childbearing age, before pregnancy. To close this immune gap and support efforts to maintain measles control, serological screening for measles antibodies should be routinely included in reproductive health and antenatal care programs to identify women without immunity who should be vaccinated before pregnancy or after delivery.

Seroprevalence and risk factors for rubella infection in pregnant women attending a tertiary hospital in Kano-Nigeria.

rubella is a leading cause of vaccine preventable birth defects especially in developing countries. Acquisition of infection with the rubella virus in early pregnancy exposes the fetus to a very high chance of developing congenital rubella syndrome. The neonate is born with multiple abnormalities with the triad of congenital cataract, deafness and cardiovascular abnormalities like ventricular septal defect or patent ductus arteriosus. Limited data exist on the seroprevalence of rubella antibodies in pregnant women in Nigeria. The aim of this study was to determine the seroprevalence of rubella antibodies in pregnant women attending antenatal clinic in Aminu Kano Teaching Hospital, Kano State. the study was a cross-sectional study involving one hundred and sixty-three pregnant women attending antenatal clinic of Aminu Kano Teaching Hospital in Kano, Nigeria. Interviewer administered questionnaire was used to collect sociodemographic data and risk factors. Blood samples were taken from consenting pregnant women during antenatal care and samples were subjected to antibody testing (IgG and IgM). Descriptive analysis was done for sociodemographic data and seroprevalence of rubella. Chi-square tests were used to determine associations. one hundred and sixty-three pregnant women were recruited for the study. The participants´ age ranged from 18 to 41 years with mean age of 27.60±5.7 years. The overall rubella seroprevalence was found to be 68.7%. The seroprevalence of specific anti-Rubella virus IgM and IgG was found to be 58.4% and 37.3% respectively while prevalence of having both anti-Rubella virus IgG and IgM in the women was found to be 26.4%. Non-formal education and immunodeficiency was found to be associated with rubella infection (P-value of 0.018 and 0.001 respectively). the study found a high prevalence of anti-Rubella virus immunoglobulins in asymptomatic pregnant women attending antenatal care in our facility with immunodeficiency and non-formal education found to be significant risk factors.

Применение моноклональных антител для лечения коронавирусной инфекции у беременных и родильниц

Aim: to compare the efficacy of monoclonal antibodies for novel coronavirus infection treatment in pregnant women. Patients and Methods: a retrospective analysis of medical reports of 502 pregnant and puerperal women aged 18–49 years with mild-to- moderate novel coronavirus infection who received monoclonal antibodies was performed. Women were divided into two groups. Group 1 included 108 women who received sotrovimab. Group 2 included 394 women who received bamlanivimab plus etesevimab. The condition was evaluated over 14 days after administering drug(s) based on the data of the general condition survey and laboratory and instrumental tests on days 1, 3, and 7 of follow-up. Lung damage was detected using ultrasound. Results: the maximum number of patients with lung damage grades 1a and 2a was identified on day 3 after starting therapy, i.e., 34.6% in the sotrovimab group and 71.8% in the bamlanivimab plus etesevimab group. On day 14 after starting therapy, most women recovered. When comparing the efficacy of two treatments, sotrovimab was superior to bamlanivimab plus etesevimab (recovery was reported in 96% and 89%, respectively). No adverse events after sotrovimab administration were reported. No therapy-associated clinically significant events were detected using ultrasound during pregnancy and the postnatal period on days 3 and 7 after drug administration. Conclusion: treatment for mild-to-moderate novel coronavirus infection with monoclonal antibodies in pregnant women is effective and reduces the number of hospital admissions, complications, and maternal and perinatal mortality. KEYWORDS: COVID-19, pregnancy, monoclonal antibodies, obstetric risk, efficacy. FOR CITATION: Polikarpova O.V., Dobrokhotova Yu.E., Shevchenko N.A., Grabovskiy V.M., Lysenko M.A. Monoclonal antibodies for coronavirus infection in pregnant and puerperal women. Russian Journal of Woman and Child Health. 2023;6(3):241–246 (in Russ.). DOI: 10.32364/2618-8430-2023-6-3-4

Red cell alloimmunization in pregnancy: a study from a premier tertiary care centre of Western India.

The study was conducted to determine the frequency of alloimmunization to various blood group antibodies in pregnant women, and the risk of hemolytic disease in the fetus and newborn. All antenatal women, irrespective of the period of gestation or obstetric history, were included, whereas those taking anti-D immune-prophylaxis or with a history of blood transfusion were excluded. Antibody screening and identification were performed using a Bio-Rad ID microtyping system. Of 2,084 antenatal females, 1,765 were D-antigen positive and 319 D-antigen negative. Sixty-five (3.119%) women alloimmunized. Out of 54 (2.591%) who had sensitized to D-antigen, 11 (0.527%) also sensitized to other antibodies. These 11 alloantibodies identified included: anti-M (n=6; 9.23%), anti-C (n=1; 3.076%), anti-E (n=1; 1.538%), anti-e (n=1; 1.538%), anti-Lewis (a) (n=1; 1.538%), and unspecified antibodies (n=1; 1.538%). Multiple antibodies were seen in four patients that combined: anti-D and anti-C (n=2; 3.076%), anti-e and anti-c (n=1; 1.538%), and anti-D and anti-G (n=1; 1.538%). The rate of alloimmunization in D-antigen-negative women was high. Apart from this, the alloimmunization rate in women with bad obstetric history was very high, at 8.1%. In developing countries such as India, universal antenatal antibody screening, though desirable, may not be justified at present, as the cost and infrastructure required would be immense because of the lower alloimmunization rates in RhD antigen-positive women. However, it is necessary to impose properly formulated protocols to screen pregnant women with bad obstetric history.

High prevalence of SARS-CoV-2 antibodies in pregnant women after the second wave of infections in the inner-city of Johannesburg, Gauteng Province, South Africa

ObjectivesAfter South Africa's second wave of COVID-19, this study estimated the SARS-CoV-2 seroprevalence among pregnant women in inner-city Johannesburg, South Africa. MethodsIn this cross-sectional survey, 500 pregnant women who were non-COVID-19-vaccinated (aged ≥12 years) were enrolled, and demographic and clinical data were collected. Serum samples were tested using the Wantai SARS-CoV-2 spike antibody enzyme-linked immunosorbent assay and Roche Elecsys® anti-SARS-CoV-2 nucleocapsid antibody assays. Seropositivity was defined as SARS-CoV-2 antibodies on either (primary) or both (secondary) assays. Univariate Poisson regression assessed risk factors associated with seropositivity. ResultsThe median age was 27.4 years, and HIV prevalence was 26.7%. SARS-CoV-2 seroprevalence was 64.0% (95% confidence interval [CI]: 59.6-68.2%) on the primary and 54% (95% CI: 49.5-58.4%) on the secondary measure. Most (96.6%) women who were SARS-CoV-2-seropositive reported no symptoms. On the Roche assay, we detected lower seroprevalence among women living with HIV than women without HIV (48.9% vs 61.7%, P-value = 0.018), and especially low levels among women living with HIV with a clusters of differentiation 4 <350 cells/ml compared with women without immune suppression (22.2% vs 56.4%, prevalence rate ratio = 0.4; 95% CI: 0.2-0.9; P-value = 0.046). ConclusionPregnant women attending routine antenatal care had a high SARS-CoV-2 seroprevalence after the second wave in South Africa, and most had asymptomatic infections. Seroprevalence surveys in pregnant women present a feasible method of monitoring the course of the pandemic over time.

Rubella-specific IgG antibodies in non-pregnant women in Rivers State, Nigeria

Background: Rubella is a contagious virus-borne disease. The study aimed to test a cohort of non-pregnant women in Rivers State for rubella virus IgG antibodies and identify their susceptibility to the viral infection. Methods: The study included 92 consenting non-pregnant women attending Rivers State University Teaching Hospital in Rivers State. The sera were evaluated for detectable anti-rubella IgG antibodies using ELISA kits according to the manufacturer's instructions. Results: Eighty-five (92.4 per cent) of the 92 samples tested positive for rubella Immunoglobulin G antibodies, while 7 (7.6 per cent) tested negative. Rubella IgG seroprevalence was unrelated to age, education, or occupation. Conclusion: Given the high level of rubella IgG among non-pregnant women tested in Rivers State, it is likely that the virus is prevalent in the research area. As a result, a robust surveillance system and the organization of screening for anti-rubella IgG antibodies in pregnant women would be critical for future protection against the illness.

Frequency of positive antiphospholipid antibodies in pregnant women with SARS-CoV-2 infection and impact on pregnancy outcome: A single-center prospective study on 151 pregnancies.

BackgroundAt the beginning of the SARS-CoV-2 pandemic, there was a lack of information about the infection’s impact on pregnancy and capability to induce de novo autoantibodies. It soon became clear that thrombosis was a manifestation of COVID-19, therefore the possible contribution of de novo antiphospholipid antibodies (aPL) raised research interest. We aimed at screening SARS-CoV-2 positive pregnant patients for aPL.MethodsThe study included consecutive pregnant women who were hospitalized in our Obstetric Department between March 2020 and July 2021 for either a symptomatic SARS-CoV-2 infection or for other reasons (obstetric complications, labour, delivery) and found positive at the admission nasopharyngeal swab. All these women underwent the search for aPL by means of Lupus Anticoagulant (LA), IgG/IgM anti-cardiolipin (aCL), IgG/IgM anti-beta2glycoprotein I (aB2GPI). Data about comorbidities, obstetric and neonatal complications were collected.Results151 women were included. Sixteen (11%) were positive for aPL, mostly at low titre. Pneumonia was diagnosed in 20 women (5 with positive aPL) and 5 required ICU admission (2 with positive aPL). Obstetric complications occurred in 10/16 (63%) aPL positive and in 36/135 (27%) negative patients. The occurrence of HELLP syndrome and preeclampsia was significantly associated with positive aPL (p=0,004). One case of maternal thrombosis occurred in an aPL negative woman. aPL positivity was checked after at least 12 weeks in 7/16 women (44%): 3 had become negative; 2 were still positive (1 IgG aB2GPI + IgG aCL; 1 IgM aB2GPI); 1 remained positive for IgG aCL but became negative for aB2GPI; 1 became negative for LA but displayed a new positivity for IgG aCL at high titre.ConclusionsThe frequency of positive aPL in pregnant women with SARS-CoV-2 infection was low in our cohort and similar to the one described in the general obstetric population. aPL mostly presented as single positive, low titre, transient antibodies. The rate of obstetric complications was higher in aPL positive women as compared to negative ones, particularly hypertensive disorders. Causality cannot be excluded; however, other risk factors, including a full-blown picture of COVID-19, may have elicited the pathogenic potential of aPL and contributed themselves to the development of complications.

Anti-Toxoplasma Gondii Antibody Seroprevalence Among Pregnant Women in Baghdad

Millions of pregnancy abnormalities occur throughout the world every year, many of which go unnoticed or untreated. The parasite Toxoplasma gondii (T. gondii) causes sometimes this infection among expectant mothors. So, the current study's goals are to evaluate the the anti-Toxoplasma IgG seroprevalence and anti-Toxoplasma IgM antibodies in pregnant women in Baghdad, as well as environmental, psychological, and behavioural factors associated with infection in women. A total of two hundred and twelve (212) pregnant Iraqi women who visited personal laboratories in Baghdad were collected. Their ages ranged from 18 to 33 years. They have all had repeated spontaneous miscarriages in the past. Sera samples were collected, and IgG and IgM levels were estimated for the study participants. 61 samples out of 212 sera examined were IgG-positive (28.8%), whereas 19 tested IgM-positive(42.4%). In (54%) of the IgG-positive patients and (3 % of the IgM cases), a history of spontaneous abortion was mentioned.while there was no significant difference in the seroprevalence of Toxoplasma IgM levels according to maternal age,the IgG levels were considerably higher(p 0.05) in older age groups.the findings showed that IgG seroprevalence tended to be lower in educated participants(11.8%) compared to the uneducated group(17%) (from primary school education up to university graduates). The majority of the study's risk factors did not significantly correlated with the seroprevalence of anti-Toxoplasma IgG and IgM antibodies, However, there was a positive coerelation between untreated water sources, cat exposure and undercooked meat with the anti-Toxoplasma IgG and IgM antibodies. A conclusion can be made that untreated water, cat handling and undercooked meat increase the seroprevalence of anti- toxoplasma antibodies as the correlation reveals a positive relation between these parameters and the anti- toxoplasma antibodies. Keywords: anti- toxoplasma antibodies, IgM, IgG, Iraq.

Pathogenetic significance of antiphospholipid antibodies in the development of placenta-associated complications in pregnant women with thrombocytopenia

BACKGROUND: Thrombocytopenia is one of the most common cytopenic syndromes that complicate pregnancy. It is considered a typical hematological criterion and the second most common manifestation of antiphospholipid syndrome. In recent years, the relationship between the development of thrombotic and placenta-associated pregnancy complications and the circulation of antiphospholipid antibodies has been actively studied, which makes it necessary to search for new methods for hemostasis correction and for prevention of the development of obstetric complications.&#x0D; AIM: The aim of this study was to assess the incidence of antiphospholipid antibodies in pregnant women with thrombocytopenia in order to determine the risk of obstetric complications and adverse pregnancy outcomes depending on the presence of antiphospholipid antibodies in the examined women.&#x0D; MATERIALS AND METHODS: 299 pregnant women were included in this multicenter prospective study: the main study group (n = 249) consisted of patients with thrombocytopenia, and the control group (n = 50) comprised women with normal platelet counts during a physiological pregnancy. All participants underwent a complete clinical and anamnestic examination and a study of the hemostasis system. To determine antibodies to cardiolipin, beta-2 glycoprotein 1, annexin V, and prothrombin (IgG/IgM/IgA), we performed enzyme-linked immunosorbent assay in 84 pregnant women with thrombocytopenia and in 25 women in the control group. Lupus anticoagulant was determined in 123 pregnant women of the main group and 25 women in the control group using an ACL-200 coagulometer (Instrumentation Laboratory, Spain).&#x0D; RESULTS: A comparative analysis of antiphospholipid antibodies detection has shown that in pregnant women with thrombocytopenia, lupus anticoagulant was detected in every third case (35.8% of cases, 44/123 women), which is more common than in the control group (8.0% of cases, 2/25 women; p = 0.008). Antibodies to beta-2 glycoprotein 1 were detected in pregnant women with thrombocytopenia in every fourth case (27.4% of cases, 23/84 women), and in the control group only in 4% of cases (1/25 women; p = 0.013). Antibodies to cardiolipin were also more often detected in pregnant women with thrombocytopenia (23.8% of cases, 20/84 women) compared to the control group (4% of cases, 1/25 women; p = 0.040). Based on the data obtained with V Cramer, we established medium-strength direct correlations between criterial antiphospholipid antibodies circulation and the development of placenta-associated complications of pregnancy (p 0.05; 0.2 V 0.4). We also identified statistically significant risks of developing placenta-associated complications in pregnant women with circulating antiphospholipid antibodies (95 % confidence interval excludes 1).&#x0D; CONCLUSIONS: Thrombocytopenia during pregnancy develops more often in women with antiphospholipid antibodies. Antiphospholipid antibodies circulation elevates coagulation potential and activates intravascular coagulation, resulting in an increased risk of placenta-associated complications of pregnancy, which requires hemostasis correction.

Factors Predicting Rubella Vaccination and Antibody in Pregnant Women in Japan: A Report from Pregnant Women Health Initiative.

This study aimed to identify the factors predicting rubella vaccination status based on self-reported data and the presence of sufficient rubella antibody titers in pregnant women in Japan. We used the results of the nationwide questionnaire survey conducted at obstetric facilities in the Pregnant Women Health Initiative Project (PWHI), with 23 participating hospitals recruiting pregnant women from June 2018–November 2019. We extracted age, the number of deliveries, educational level, household income, pre-pregnancy smoking, and knowledge of rubella from questionnaires and medical records. We analyzed the association of rubella vaccination status and antibodies with each of these factors. We found that the number of previous deliveries, educational level, annual household income, smoking before pregnancy, and knowledge of rubella were factors predicting self-reported rubella vaccination status, while age and the number of previous deliveries were identified as factors predicting the presence of sufficient rubella antibody titers (32 folds or higher). Women considering pregnancy should be immunized against rubella to prevent congenital rubella syndrome in the future. Furthermore, social policies are needed to strongly encourage vaccination, especially for all citizens who were not given the opportunity or missed the chance to be vaccinated against rubella.

Anti-human platelet antigen-5b antibodies and fetal and neonatal alloimmune thrombocytopenia; incidental association or cause and effect?

Most cases of fetal and neonatal thrombocytopenia (FNAIT) are caused by maternal anti-human platelet antigen-1a antibodies (anti-HPA-1a). Anti-HPA-5b antibodies are the second most common antibodies in suspected FNAIT cases. Given the high prevalence of anti-HPA-5b antibodies in pregnant women delivering healthy newborns, the association with FNAIT may be coincidental. This review of the literature related to FNAIT using the MEDLINE database was conducted according to PRISMA guidelines. A retrospective analysis of a single-centre cohort of 817 suspected FNAIT cases was conducted. The pooled prevalence of anti-HPA-5b antibodies in unselected pregnant women of European descent was 1.96% (n=3113), compared with 3.4% (n=5003) in women with suspected FNAIT. We found weak evidence that a small proportion of pregnant women presenting with anti-HPA-5b antibodies will give birth to a newborn with mild thrombocytopenia. The neonatal platelet counts were not different between suspected FNAIT cases (n=817) with and without maternal anti-HPA-5b antibodies. The prevalence of maternal anti-HPA-5b antibodies was not different between neonates with intracranial haemorrhage and healthy controls. The current experimental and epidemiological evidence does not support the hypothesis that anti-HPA-5b antibodies cause severe thrombocytopenia or bleeding complications in the fetus or newborn.

Efficiency of transplacental transfer of respiratory syncytial virus (RSV) specific antibodies among pregnant women in Kenya.

Background: Maternal immunisation to boost respiratory syncytial virus (RSV) antibodies in pregnant women, is a strategy being considered to enhance infant protection from severe RSV associated disease. However, little is known about the efficiency of transplacental transfer of RSV-specific antibodies in a setting with a high burden of malaria and HIV, to guide the implementation of such a vaccination program. Methods: Using a plaque reduction neutralization assay, we screened 400 pairs of cord and maternal serum specimens from pregnant women for RSV-specific antibodies. Participants were pregnant women of two surveillance cohorts: 200 participants from a hospital cohort in Kilifi, Coastal Kenya and 200 participants from a surveillance cohort in Siaya, Western Kenya. Transplacental transfer efficiency was determined by the cord to maternal titre ratio (CMTR). Logistic regression was used to determine independent predictors of impaired transplacental transfer of RSV-specific antibodies. Results: A total of 800 samples were screened from the 400 participants. At enrollment the median age was 25 years (Interquartile range (IQR): 21-31). Overall, transplacental transfer was efficient and did not differ between Kilifi and Siaya cohort (1.02 vs. 1.02; p=0.946) but was significantly reduced among HIV-infected mothers compared to HIV-uninfected mothers (mean CMTR: 0.98 vs 1.03; p=0.015). Prematurity <33 weeks gestation (Odds ratio [OR]: 0.23, 95% confidence interval [CI] 0.06-0.85; p=0.028), low birth weight <2.5 kgs (OR: 0.25, 95% CI: 0.07-0.94; p=0.041) and HIV infection (OR: 0.47, 95% CI:0.23-0.98; p=0.045) reduced efficiency of transplacental transfer among these women. Conclusions: Transplacental transfer of RSV-specific antibodies among pregnant women in Kenya is efficient. A consideration to integrate other preventive interventions with maternal RSV vaccination targeting infants born premature (<33 weeks gestation), with low birth weight <2.5 kgs, or HIV-infected mothers is likely to improve vaccine outcomes in this setting.

Efficiency of transplacental transfer of respiratory syncytial virus (RSV) specific antibodies among pregnant women in Kenya

Background: Maternal immunisation to boost respiratory syncytial virus (RSV) antibodies in pregnant women, is a strategy being considered to enhance infant protection from severe RSV associated disease. However, little is known about the efficiency of transplacental transfer of RSV-specific antibodies in a setting with a high burden of malaria and HIV, to guide the implementation of such a vaccination program. Methods: Using a plaque reduction neutralization assay, we screened 400 pairs of cord and maternal serum specimens from pregnant women for RSV-specific antibodies. Participants were pregnant women of two surveillance cohorts: 200 participants from a hospital cohort in Kilifi, Coastal Kenya and 200 participants from a surveillance cohort in Siaya, Western Kenya. Transplacental transfer efficiency was determined by the cord to maternal titre ratio (CMTR). Logistic regression was used to determine independent predictors of impaired transplacental transfer of RSV-specific antibodies. Results: A total of 800 samples were screened from the 400 participants. At enrollment the median age was 25 years (Interquartile range (IQR): 21-31). Overall, transplacental transfer was efficient and did not differ between Kilifi and Siaya cohort (1.02 vs. 1.02; p=0.946) but was significantly reduced among HIV-infected mothers compared to HIV-uninfected mothers (mean CMTR: 0.98 vs 1.03; p=0.015). Prematurity <33 weeks gestation (Odds ratio [OR]: 0.23, 95% confidence interval [CI] 0.06–0.85; p=0.028), low birth weight <2.5 kgs (OR: 0.25, 95% CI: 0.07–0.94; p=0.041) and HIV infection (OR: 0.47, 95% CI:0.23-0.98; p=0.045) reduced efficiency of transplacental transfer among these women. Conclusions: Transplacental transfer of RSV-specific antibodies among pregnant women in Kenya is efficient. A consideration to integrate other preventive interventions with maternal RSV vaccination targeting infants born premature (<33 weeks gestation), with low birth weight <2.5 kgs, or HIV-infected mothers is likely to improve vaccine outcomes in this setting.

Efficiency of transplacental transfer of respiratory syncytial virus (RSV) specific antibodies among pregnant women in Kenya

Background: Maternal immunisation to boost respiratory syncytial virus (RSV) antibodies in pregnant women, is a strategy being considered to enhance infant protection from severe RSV associated disease. However, little is known about the efficiency of transplacental transfer of RSV-specific antibodies in a setting with a high burden of malaria and HIV, to guide the implementation of such a vaccination program. Methods: Using a plaque reduction neutralization assay, we screened 400 pairs of cord and maternal serum specimens from pregnant women for RSV-specific antibodies. Participants were pregnant women of two surveillance cohorts: 200 participants from a hospital cohort in Kilifi, Coastal Kenya and 200 participants from a surveillance cohort in Siaya, Western Kenya. Transplacental transfer efficiency was determined by the cord to maternal transfer ratio (CMTR). Logistic regression was used to determine independent predictors of impaired transplacental transfer of RSV-specific antibodies. Results: A total of 800 samples were screened from the 400 participants. At enrollment the median age was 25 years (Interquartile range (IQR): 21-31). Overall, transplacental transfer was efficient and did not differ between Kilifi and Siaya cohort (1.02 vs. 1.02; p=0.946) but was significantly reduced among HIV-infected mothers compared to HIV-uninfected mothers (mean CMTR: 0.98 vs 1.03; p=0.015). Prematurity &lt;33 weeks gestation (Odds ratio [OR]: 0.23, 95% confidence interval [CI] 0.06–0.85; p=0.028), low birth weight &lt;2.5 kgs (OR: 0.25, 95% CI: 0.07–0.94; p=0.041) and HIV infection (OR: 0.47, 95% CI:0.23-0.98; p=0.045) reduced efficiency of transplacental transfer among these women. Conclusions: Transplacental transfer of RSV-specific antibodies among pregnant women in Kenya is efficient. A consideration to integrate other preventive interventions with maternal RSV vaccination targeting infants born premature (&lt;33 weeks gestation), with low birth weight &lt;2.5 kgs, or HIV-infected mothers is likely to improve vaccine outcomes in this setting.

Seroepidemiology study of Cytomegalovirus and Rubella in pregnant women in Luanda, Angola: geospatial distribution and its association with socio-demographic and clinical-obstetric determinants

BackgroundBoth CMV and Rubella virus infections are associated with the risk of vertical transmission, fetal death or congenital malformations. In Angola, there are no reports of CMV and Rubella studies. Therefore, our objectives were to study the seroprevalence of anti-CMV and anti-Rubella antibodies in pregnant women of Luanda (Angola), identify the risk of primary infection during pregnancy and evaluate the socio-demographic risk factors associated with both infections.MethodsA prospective cross-sectional study was conducted from August 2016 to May 2017. Specific anti-CMV and anti-Rubella antibodies were quantified by electrochemiluminescence and demographic and clinical data were collected using standardized questionnaire. Bivariate and multivariate logistic regression analysis were used to quantify the effect of clinical and obstetric risk factors on virus seroprevalence.ResultsWe recruited 396 pregnant women aged from 15 to 47. Among them, 335 (84.6%) were immune to both CMV and Rubella virus infections, while 8 (2.0%) had active CMV infection and 4 (1.0%) active RV infection but none had an active dual infection. Five women (1.2%) were susceptible to only CMV infection, 43 (10.9%) to only RV infection, and 1 (0.3) to both infections. Multivariate analysis showed a significant association between Rubella virus infection and number of previous births and suffering spontaneous abortion.ConclusionsOverall, this study showed that there is a high prevalence of anti-CMV and anti-Rubella antibodies in pregnant women in Luanda. It also showed that a small but important proportion of pregnant women, about 11%, are at risk of primary infection with rubella during pregnancy. This emphasizes the need for vaccination.