Ugandan Infants Research Articles

Cost-Effectiveness of Dolutegravir Compared With Efavirenz for Prevention of Perinatal Transmission in Women Presenting With HIV in Late Pregnancy in Uganda

ObjectivesDolutegravir (DTG) has proved to be more efficacious, tolerable, and safer than efavirenz (EFV) among mothers living with HIV and their infants in Uganda. This study assessed the cost-effectiveness of the DTG-based antiretroviral therapy (ART) compared with the standard of care for preventing perinatal transmissions among pregnant women initiating ART in late pregnancy in Uganda. MethodsWe used data from a randomized open-label trial (DolPHIN-2) and a 2-part cost-effectiveness model composed of a short-term decision tree to estimate the perinatal transmission rate and costs and an individual-based 3-state Markov model (HIV, advanced HIV, dead) to estimate the long-term costs and health outcomes from the Ugandan payer perspective using a lifetime horizon and a 1-year Markov cycle. The main outcomes were the mean annual costs in US dollars ($), disability-adjusted life-years (DALYs), and incremental cost-effectiveness ratio. Both the deterministic and probabilistic sensitivity analyses were conducted to assess the effect of parameter uncertainties on the ultimate results and the model’s robustness. ResultsCompared with the EFV-based ART, the DTG-based ART was associated with fewer mean annual costs ($43.58 vs $68.44) and DALYs (0.33 vs 0.56), leading to cost savings of $110 per DALY averted. In the incremental analysis, the DTG-based ART dominated the EFV-based ART; that is, it was less costly and more effective. These results were robust to deterministic and probabilistic sensitivity analyses. ConclusionThe DTG-based ART is a highly cost-effective strategy compared with the EFV-based ART among women initiating treatment in the third trimester of pregnancy in a low-income setting.

Seroepidemiology of SARS-CoV-2 in a cohort of pregnant women and their infants in Uganda and Malawi.

Data on SARS-CoV-2 infection in pregnancy and infancy has accumulated throughout the course of the pandemic, though evidence regarding asymptomatic SARS-CoV-2 infection and adverse birth outcomes are scarce. Limited information is available from countries in sub-Saharan Africa (SSA). The pregnant woman and infant COVID in Africa study (PeriCOVID Africa) is a South-South-North partnership involving hospitals and health centres in five countries: Malawi, Uganda, Mozambique, The Gambia, and Kenya. The study leveraged data from three ongoing prospective cohort studies: Preparing for Group B Streptococcal Vaccines (GBS PREPARE), SARS-CoV-2 infection and COVID-19 in women and their infants in Kampala and Mukono (COMAC) and Pregnancy Care Integrating Translational Science Everywhere (PRECISE). In this paper we describe the seroepidemiology of SARS-CoV-2 infection in pregnant women enrolled in sites in Uganda and Malawi, and the impact of SARS-CoV-2 infection on pregnancy and infant outcomes. Seroprevalence of SARS-CoV-2 antibodies in maternal blood, reported as the proportion of seropositive women by study site and wave of COVID-19 within each country. The PeriCOVID study was a prospective mother-infant cohort study that recruited pregnant women at any gestation antenatally or on the day of delivery. Maternal and cord blood samples were tested for SARS-CoV-2 antibodies using Wantai and Euroimmune ELISA. In periCOVID Uganda and Malawi nose and throat swabs for SARS-Cov-2 RT-PCR were obtained. In total, 1379 women were enrolled, giving birth to 1387 infants. Overall, 63% of pregnant women had a SARS-CoV-2 positive serology. Over subsequent waves (delta and omicron), in the absence of vaccination, seropositivity rose from 20% to over 80%. The placental transfer GMR was 1.7, indicating active placental transfer of anti-spike IgG. There was no association between SARS-CoV-2 antibody positivity and adverse pregnancy or infancy outcomes.

Paenibacillus spp infection among infants with postinfectious hydrocephalus in Uganda: an observational case-control study

Paenibacillus thiaminolyticus is a cause of postinfectious hydrocephalus among Ugandan infants. To determine whether Paenibacillus spp is a pathogen in neonatal sepsis, meningitis, and postinfectious hydrocephalus, we aimed to complete three separate studies of Ugandan infants. The first study was on peripartum prevalence of Paenibacillus in mother-newborn pairs. The second study assessed Paenibacillus in blood and cerebrospinal fluid (CSF) from neonates with sepsis. The third study assessed Paenibacillus in CSF from infants with hydrocephalus. In this observational study, we recruited mother-newborn pairs with and without maternal fever (mother-newborn cohort), neonates (aged ≤28 days) with sepsis (sepsis cohort), and infants (aged ≤90 days) with hydrocephalus with and without a history of neonatal sepsis and meningitis (hydrocephalus cohort) from three hospitals in Uganda between Jan 13, 2016 and Oct 2, 2019. We collected maternal blood, vaginal swabs, and placental samples and the cord from the mother-newborn pairs, and blood and CSF from neonates and infants. Bacterial content of infant CSF was characterised by 16S rDNA sequencing. We analysed all samples using quantitative PCR (qPCR) targeting either the Paenibacillus genus or Paenibacillus thiaminolyticus spp. We collected cranial ultrasound and computed tomography images in the subset of participants represented in more than one cohort. No Paenibacillus spp were detected in vaginal, maternal blood, placental, or cord blood specimens from the mother-newborn cohort by qPCR. Paenibacillus spp was detected in 6% (37 of 631 neonates) in the sepsis cohort and, of these, 14% (5 of 37 neonates) developed postinfectious hydrocephalus. Paenibacillus was the most enriched bacterial genera in postinfectious hydrocephalus CSF (91 [44%] of 209 patients) from the hydrocephalus cohort, with 16S showing 94% accuracy when validated by qPCR. Imaging showed progression from Paenibacillus spp-related meningitis to postinfectious hydrocephalus over 1-3 months. Patients with postinfectious hydrocephalus with Paenibacillus spp infections were geographically clustered. Paenibacillus spp causes neonatal sepsis and meningitis in Uganda and is the dominant cause of subsequent postinfectious hydrocephalus. There was no evidence of transplacental transmission, and geographical evidence was consistent with an environmental source of neonatal infection. Further work is needed to identify routes of infection and optimise treatment of neonatal Paenibacillus spp infection to lessen the burden of morbidity and mortality. National Institutes of Health and Boston Children's Hospital Office of Faculty Development.

Transition from hospital to home care for preterm babies: A qualitative study of the experiences of caregivers in Uganda.

Improving care for preterm babies could significantly increase child survival in low-and middle income countries. However, attention has mainly focused on facility-based care with little emphasis on transition from hospital to home after discharge. Our aim was to understand the experiences of the transition process among caregivers of preterm infants in Uganda in order to improve support systems. A qualitative study among caregivers of preterm infants in Iganga and Jinja districts in eastern Uganda was conducted in June 2019 through February 2020, involving seven focus group discussions and five in-depth interviews. We used thematic-content analysis to identify emergent themes related to the transition process. We included 56 caregivers, mainly mothers and fathers, from a range of socio-demographic backgrounds. Four themes emerged: caregivers' experiences through the transition process from preparation in the hospital to providing care at home; appropriate communication; unmet information needs; and managing community expectations and perceptions. In addition, caregivers' views on 'peer-support' was explored. Caregivers' experiences, and their confidence and ability to provide care were related to preparation in the hospital after birth and until discharge, the information they received and the manner in which healthcare providers communicated. Healthcare workers were a trusted source of information while in the hospital, but there was no continuity of care after discharge which increased their fears and worries about the survival of their infant. They often felt confused, anxious and discouraged by the negative perceptions and expectations from the community. Fathers felt left-out as there was very little communication between them and the healthcare providers. Peer-support could enable a smooth transition from hospital to home care. Interventions to advance preterm care beyond the health facility through a well-supported transition from facility to home care are urgently required to improve health and survival of preterm infants in Uganda and other similar settings.

A cluster randomised trial to evaluate the effectiveness of household alcohol-based hand rub for the prevention of sepsis, diarrhoea, and pneumonia in Ugandan infants (the BabyGel trial): a study protocol

BackgroundInfections are one of the leading causes of death in the neonatal period. This trial aims to evaluate if the provision of alcohol-based hand rub (ABHR) to pregnant women for postnatal household use prevents severe infections (including sepsis, diarrhoea, pneumonia, or death) among infants during the first three postnatal months.MethodsThrough a cluster-randomised trial in eastern Uganda, 72 clusters are randomised in a 2-arm design with rural villages as units of randomisation. We estimate to include a total of 5932 pregnant women at 34 weeks of gestation. All women and infants in the study are receiving standard antenatal and postnatal care. Women in the intervention group additionally receive six litres of ABHR and training on its use. Research midwives conduct follow-up visits at participants’ homes on days 1, 7, 28, 42, and 90 after birth and telephone calls on days 14, 48, and 60 to assess the mother and infant for study outcomes. Primary analyses will be by intention to treat.DiscussionThis study will provide evidence on the effectiveness of a locally available and low-cost intervention in preventing neonatal sepsis and early infant infections. If ABHR is found effective, it could be implemented by adding it to birthing kits.Trial registrationPan African Clinical Trial Registry, PACTR202004705649428. Registered 1 April 2020, https://pactr.samrc.ac.za/.

Maternal attitudes and behaviours differentially shape infant early life experience: A cross cultural study.

Early life environments afford infants a variety of learning opportunities, and caregivers play a fundamental role in shaping infant early life experience. Variation in maternal attitudes and parenting practices is likely to be greater between than within cultures. However, there is limited cross-cultural work characterising how early life environment differs across populations. We examined the early life environment of infants from two cultural contexts where attitudes towards parenting and infant development were expected to differ: in a group of 53 mother-infant dyads in the UK and 44 mother-infant dyads in Uganda. Participants were studied longitudinally from when infants were 3- to 15-months-old. Questionnaire data revealed the Ugandan mothers had more relational attitudes towards parenting than the mothers from the UK, who had more autonomous parenting attitudes. Using questionnaires and observational methods, we examined whether infant development and experience aligned with maternal attitudes. We found the Ugandan infants experienced a more relational upbringing than the UK infants, with Ugandan infants receiving more distributed caregiving, more body contact with their mothers, and more proximity to mothers at night. Ugandan infants also showed earlier physical development compared to UK infants. Contrary to our expectations, however, Ugandan infants were not in closer proximity to their mothers during the day, did not have more people in proximity or more partners for social interaction compared to UK infants. In addition, when we examined attitudes towards specific behaviours, mothers' attitudes rarely predicted infant experience in related contexts. Taken together our findings highlight the importance of measuring behaviour, rather than extrapolating expected behaviour based on attitudes alone. We found infants' early life environment varies cross-culturally in many important ways and future research should investigate the consequences of these differences for later development.

Vitamin D deficiency in low-birth-weight infants in Uganda; a cross sectional study.

Vitamin D deficiency affects 7-86% of infants globally and results in recurrent infections, impaired growth and nutritional rickets. Low-birth-weight infants in Uganda are at risk of vitamin D deficiency due to limited sunlight exposure and dependence on breastmilk. We aimed to determine the prevalence and factors associated with vitamin D deficiency among low-birth-weight infants aged 6 weeks to 6 months at Mulago national referral hospital in Uganda. We conducted a cross-sectional study at Mulago Hospital between September 2016 and March 2017. We enrolled infants born with low birth weight between six weeks and six months whose mothers were available and willing to provide informed consent. Upon obtaining informed consent, we administered a structured questionnaire and performed a physical examination on the participants. Blood was drawn for calcium, phosphorus and vitamin D estimation. We measured serum 25 hydroxy vitamin D (25(OH)D) using the electrochemiluminescence method. Vitamin D deficiency and insufficiency were defined as (25(OH)D) < 20ng/ml and from 20ng/ml to <30 ng/ml respectively. To determine factors associated with vitamin D deficiency, we fit multivariable logistic regression models with exposure factors determined a priori. Data were analysed using Stata version 14. We enrolled 297 participants, 49.2% (167/297) of whom were males. The median infant age was nine weeks (interquartile range 7-13). All infants had less than one hour of sunlight exposure and over 90.6% (269/297) had received multivitamin supplements containing vitamin D. The prevalence of vitamin D deficiency was 12.1% (36/297): 95% CI (8.9%-16.4%). The prevalence of vitamin D insufficiency was 19.9% (59/297): 95% CI (15.7%-24.8%). Boys had higher odds of vitamin D deficiency compared to girls [adjusted odds ratio 2.8: 95% CI 1.3-6.1]. Vitamin D deficiency was 12.1% among low-birth-weight infants in Uganda although almost all of them had received multivitamin supplements containing vitamin D. We recommend that more studies are done in low-birth-weight infants to assess the risk factors for vitamin D in these population in Uganda.

HIV viral load assays when used with whole blood perform well as a diagnostic assay for infants.

Over the past several years, only approximately 50% of HIV-exposed infants received an early infant diagnosis test within the first two months of life. While high attrition and mortality account for some of the shortcomings in identifying HIV-infected infants early and putting them on life-saving treatment, fragmented and challenging laboratory systems are an added barrier. We sought to determine the accuracy of using HIV viral load assays for infant diagnosis of HIV. We enrolled 866 Ugandan infants between March-April 2018 for this study after initial laboratory diagnosis. The median age was seven months, while 33% of infants were less than three months of age. Study testing was done using either the Roche or Abbott molecular technologies at the Central Public Health Laboratory. Dried blood spot samples were prepared according to manufacturer-recommended protocols for both the qualitative and quantitative assays. Viral load test samples for the Roche assay were processed using two different buffers: phosphate-buffered saline (PBS: free virus elution viral load protocol [FVE]) and Sample Pre-Extraction Reagent (SPEX: qualitative buffer). Dried blood spot samples were processed for both assays on the Abbott using the manufacturer's standard infant diagnosis protocol. All infants received a qualitative test for clinical management and additional paired quantitative tests. 858 infants were included in the analysis, of which 50% were female. Over 75% of mothers received antiretroviral therapy, while approximately 65% of infants received infant prophylaxis. The Roche SPEX and Abbott technologies had high sensitivity (>95%) and specificity (>98%). The Roche FVE had lower sensitivity (85%) and viral load values. To simplify and streamline laboratory practices, HIV viral load may be used to diagnose HIV infection in infants, particularly using the Roche SPEX and Abbott technologies.

Child stunting starts in utero: Growth trajectories and determinants in Ugandan infants.

Childhood stunting remains a public health burden worldwide. Although many studies have examined early life and in‐utero risk factors; most have been observational and have used analytic techniques that make inferences limited to population means, thereby obscuring important within‐group variations. This study addressed that important gap. Using data from a birth cohort of Ugandan infants (n = 4528), we applied group‐based trajectory modelling to assess diverse patterns of growth among children from birth to 1‐year old. A multinomial regression model was conducted to understand the relationship between risk factors and observed patterns across groups. We found that the onset of stunting occurred before birth and followed four distinct growth patterns: chronically stunted (Group 1), recovery (Group 2), borderline stunted (Group 3) and normal (Group 4). The average length‐for‐age z‐score (LAZ) at birth was −2.6, −3.9, −0.6 and 0.5 for Groups 1–4, respectively. Although both Groups 1 and 2 were stunted at birth, stunting persisted in Group 1 while children in Group 2 recovered by the fourth month. Group 3 exhibited mild stunting while Group 4 was normal. Wasting and underweight were observed in all groups, with the highest prevalence of underweight in Group 1. Wasting gradually increased among children born already stunted (Groups 1 and 2). This showed the importance of distinguishing children by their growth patterns rather than aggregating them and only comparing population averages against global growth standards. The design of nutrition interventions should consider the differential factors and potential for growth gains relative to different risks within each group.

Cytomegalovirus infections in infants in Uganda: Newborn-mother pairs, neonates with sepsis, and infants with hydrocephalus

ObjectivesTo estimate the prevalence of cytomegalovirus (CMV) infections among newborn-mother pairs, neonates with sepsis, and infants with hydrocephalus in Uganda. Design and MethodsThree populations—newborn-mother pairs, neonates with sepsis, and infants (≤3 months) with nonpostinfectious (NPIH) or postinfectious (PIH) hydrocephalus—were evaluated for CMV infection at 3 medical centers in Uganda. Quantitative PCR (qPCR) was used to characterize the prevalence of CMV. ResultsThe overall CMV prevalence in 2498 samples across all groups was 9%. In newborn-mother pairs, there was a 3% prevalence of cord blood CMV positivity and 33% prevalence of maternal vaginal shedding. In neonates with clinical sepsis, there was a 2% CMV prevalence. Maternal HIV seropositivity (adjusted odds ratio [aOR] 25.20; 95% confidence interval [CI] 4.43–134.26; p = 0.0001), residence in eastern Uganda (aOR 11.06; 95% CI 2.30–76.18; p = 0.003), maternal age <25 years (aOR 4.54; 95% CI 1.40–19.29; p = 0.02), and increasing neonatal age (aOR 1.08 for each day older; 95% CI 1.00–1.16; p = 0.05), were associated risk factors for CMV in neonates with clinical sepsis. We found a 2-fold higher maternal vaginal shedding in eastern (45%) vs western (22%) Uganda during parturition (n = 22/49 vs 11/50, the Fisher exact test; p = 0.02). In infants with PIH, the prevalence in blood was 24% and in infants with NPIH, it was 20%. CMV was present in the cerebrospinal fluid (CSF) of 13% of infants with PIH compared with 0.5% of infants with NPIH (n = 26/205 vs 1/194, p < 0.0001). ConclusionsOur findings highlight that congenital and postnatal CMV prevalence is substantial in this African setting, and the long-term consequences are uncharacterized.

Characterization of Adaptive-like γδ T Cells in Ugandan Infants during Primary Cytomegalovirus Infection.

Gamma-delta (γδ) T cells are unconventional T cells that help control cytomegalovirus (CMV) infection in adults. γδ T cells develop early in gestation, and a fetal public γδ T cell receptor (TCR) clonotype is detected in congenital CMV infections. However, age-dependent γδ T cell responses to primary CMV infection are not well-understood. Flow cytometry and TCR sequencing was used to comprehensively characterize γδ T cell responses to CMV infection in a cohort of 32 infants followed prospectively from birth. Peripheral blood γδ T cell frequencies increased during infancy, and were higher among CMV-infected infants relative to uninfected. Clustering analyses revealed associations between CMV infection and activation marker expression on adaptive-like Vδ1 and Vδ3, but not innate-like Vγ9Vδ2 γδ T cell subsets. Frequencies of NKG2C+CD57+ γδ T cells were temporally associated with the quantity of CMV shed in saliva by infants with primary infection. The public γδ TCR clonotype was only detected in CMV-infected infants <120 days old and at lower frequencies than previously described in fetal infections. Our findings support the notion that CMV infection drives age-dependent expansions of specific γδ T cell populations, and provide insight for novel strategies to prevent CMV transmission and disease.

Cytomegalovirus Infections in Ugandan Infants:Newborns, Neonates with Sepsis and Infants with Hydrocephalus

Background: Congenital and postnatal cytomegalovirus (CMV) infections in Uganda is prevalent and may compromise the health of Ugandan children. The objective of this study is to estimate the prevalence of CMV infections in newborns, neonates with sepsis, and infants with hydrocephalus in Uganda. Methods: Three populations: (1) newborn-mother pairs, (2) neonates with sepsis, and (3) infants (≤ 3 months) with non-postinfectious (NPIH) or postinfectious (PIH) hydrocephalus, were evaluated over four years (2016-2019) for CMV infection at three medical centers – two in the Eastern (Mbale) and one in Western (Mbarara) Uganda. To characterize the prevalence of CMV we used quantitative PCR (qPCR) analysis. In newborn-mother pairs maternal blood (n=99) and a subset of matching cord blood (n=92), placental tissue (n=99), and vaginal specimens (n=99) were tested for CMV. In neonates and infants aged 3 months or less, peripheral blood (751 with sepsis, 399 with hydrocephalus) and cerebrospinal fluid samples (560 with sepsis, 399 with hydrocephalus (205 PIH, 194 NPIH) were also tested for CMV. Findings: The overall CMV prevalence across all groups was 9%. In newborn-mother pairs, a 3% (n=3/92; 95% CI, 1-9%) prevalence of cord blood positivity and 33% (n=33/99; 95% CI, 24-44%) prevalence of maternal vaginal shedding of CMV was estimated. In neonates with clinical sepsis, a 2% (n=17/751; 95% CI, 1-4%) CMV prevalence was estimated. Maternal HIV seropositivity (adjusted odds ratio [aOR], 21.09; 95% CI, 4-109; p= 0.0002), residence in Eastern Uganda (aOR, 11.10; 95% CI, 3-77; p=0 .003), maternal age < 25 years (aOR, 4.91; 95% CI, 2-20; p=0.012), and older neonatal age (9 days vs. 5 days; p= 0.006) were associated with CMV in neonates with clinical sepsis. In infants with PIH, the prevalence in blood was 24% (n=50/205; 95% CI, 19-31%) and in infants with NPIH it was 20% (n=39/194; 95% CI, 15-26%; p=0.34). CMV was present in the CSF of 13% (n=26/205; 95% CI, 8-18%) of infants with PIH compared to 0.5% of infants with NPIH (n=1/194; 95% CI, 0-3%, p<0.0001). Interpretation: Our findings highlight that congenital and postnatal CMV prevalence is high in this African setting and the associated complications may be significant. Universal testing and longitudinal studies are critical to understand the burden infant CMV has in sub-Saharan African countries. Funding Statement: U.S. National Institutes of Health (N.I.H) Director’s Pioneer Award 5DP1HD086071 and NIH Director’s Transformative Award 1R01AI145057. Declaration of Interests: No conflict of interest reported. Ethics Approval Statement: For all participants, mothers had to be at least 18 years of age and able to give informed written consent in either English, Lumasaba, Lugwere, Luganda, Ateso or Runyankole. The study was performed with approval from the CCHU Institutional Review Board, the Mbarara University of Science and Technology Research Ethics Committee, the Pennsylvania State University Institutional Review Board, and with oversight from the Ugandan National Council on Science and Technology. Material Transfer Agreements and a US Centers for Disease Control permit were obtained for the proper transfer and importation of samples to the Pennsylvania State University.

Growth Faltering and Developmental Delay in HIV-Exposed Uninfected Ugandan Infants: A Prospective Cohort Study.

HIV-exposed but uninfected (HEU) infants are at increased risk of impaired early linear growth and cognitive development. We examined associations between prenatal and postnatal growth and subsequent neurodevelopment in Ugandan HEU infants, hypothesizing that early insults may explain alterations in both somatic growth and brain development. We prospectively followed a cohort of HEU infants from birth to 18 months of age, and measured length/height, weight, head, and arm circumference longitudinally. The Malawi Development Assessment Tool (MDAT, 12 and 18 months) and the Color Object Association Test (18 months) were used for developmental assessments. Among 170 HEU infants, the prevalence of low-birth weight and failure to thrive was 7.6% and 37%, respectively. HEU infants had MDAT scores that were similar to the reference population. The mean (SD) score on the Color Object Association Test was 5.5 (3.1) compared with 6.9 (5.3) in developmentally normal children. Developmental ability at age 18 months showed strong cross-sectional correlation with weight-for-age (ρ = 0.36, P < 0.0001), length/height-for-age (ρ = 0.41, P < 0.0001), head circumference-for-age (ρ = 0.26, P = 0.0011), and mid-upper arm circumference-for-age (ρ = 0.34, P = 0.0014). There was a statistically significant correlation between birth weight and MDAT z-score at 18 months (ρ = 0.20, P = 0.010). Failure to thrive was associated with lower MDAT z-score [median -0.13 (IQR -0.75 to +0.14) versus +0.14 (IQR -0.44 to +0.63), P = 0.042]. Growth faltering in HEU infants was associated with lower attainment of developmental milestones at age 18 months. Our findings point to a simple screening method for identifying HEU infants at risk for developmental intervention.

Immune Responses Following BCG Immunization of Infants in Uganda and United Kingdom Are Similar for Purified Protein Derivative but Differ for Secretory Proteins of Mycobacterium tuberculosis.

Introduction: The immunogenicity of BCG vaccination in infants differs between populations. We hypothesized that prenatal exposure to mycobacterial antigens might explain the differences in immune responses to BCG seen in other studies of infants in Africa and the United Kingdom (UK) and we explored this in birth cohorts in Uganda and the UK.Materials and Methods: Blood samples were obtained from BCG-immunized infants of mothers with (n = 110) and without (n = 121) latent Mycobacterium tuberculosis infection (LTBI) in Uganda and BCG-immunized infants of mothers without LTBI (n = 25) in the UK at 10 and 52 weeks after birth. Cytokine and chemokine responses to PPD were measured to assess responses to BCG immunization, and to ESAT6/CFP10 to assess exposure to or infection with M. tuberculosis or non-tuberculous mycobacteria (NTM) in 6-day whole blood culture supernatants by a 17-plex Luminex assay. Median responses were compared between Ugandan infants (together, and separated by maternal LTBI status) and UK infants.Results: The IFN-γ response to BCG vaccination was similar between Ugandan and UK infants at 10 and 52 weeks. At week 52, TNF production was marginally higher in Ugandan infants, but after adjusting for multiple comparisons this difference was not significant. At weeks 10 and 52, stimulation of blood with ESAT6/CFP10 produced significantly higher IFN-γ, TNF, IL-12p40, IL-1α, IL-1β, IL-1Ra, IP-10, MIP-1α, MIP-1β, and GM-CSF in Ugandan compared to UK infants. Stimulation of blood with ESAT6/CFP10 produced significantly higher amounts of IL-8 (p = 0.0001), IL-10 (p = 0.0022), and IL-13 (p = 0.0020) in the UK than in Ugandan infants of mothers without LTBI at week 10, but not at week 52.Conclusions: Immune responses to mycobacterial antigens following BCG immunization are similar for PPD, but differ for ESAT6/CFP10, between infants in Uganda and the UK. Neither maternal LTBI nor infant exposure to or infection with mycobacteria impacts the response to BCG. The observed global differences in immune response to BCG immunization are likely to be due to other causes.

A longitudinal study of plasma BAFF levels in mothers and their infants in Uganda, and correlations with subsets of B cells.

Malaria is a potentially life-threatening disease with approximately half of the world’s population at risk. Young children and pregnant women are hit hardest by the disease. B cells and antibodies are part of an adaptive immune response protecting individuals continuously exposed to the parasite. An infection with Plasmodium falciparum can cause dysregulation of B cell homeostasis, while antibodies are known to be key in controlling symptoms and parasitemia. BAFF is an instrumental cytokine for the development and maintenance of B cells. Pregnancy alters the immune status and renders previously clinically immune women at risk of severe malaria, potentially due to altered B cell responses associated with changes in BAFF levels. In this prospective study, we investigated the levels of BAFF in a malaria-endemic area in mothers and their infants from birth up to 9 months. We found that BAFF-levels are significantly higher in infants than in mothers. BAFF is highest in cord blood and then drops rapidly, but remains significantly higher in infants compared to mothers even at 9 months of age. We further correlated BAFF levels to P. falciparum-specific antibody levels and B cell frequencies and found a negative correlation between BAFF and both P. falciparum-specific and total proportions of IgG+ memory B cells, as well as CD27− memory B cells, indicating that exposure to both malaria and other diseases affect the development of B-cell memory and that BAFF plays a part in this. In conclusion, we have provided new information on how natural immunity against malaria is formed.

Maternal Epstein-Barr Virus-Specific Antibodies and Risk of Infection in Ugandan Infants.

Epstein-Barr virus (EBV) infection is a major cause of malignancy worldwide. Maternal antibody is thought to prevent EBV infection because it is uncommon in early infancy. Maternal HIV infection is associated with an increased incidence of EBV infection in exposed infants, which we hypothesized results from impaired transfer of EBV-neutralizing maternal antibodies. Among Ugandan infants followed for EBV acquisition from birth, we measured antibody binding to EBV glycoproteins (gp350, gH/gL) involved in B-cell and epithelial-cell entry, as well as viral neutralization and antibody-dependent cellular cytotoxicity (ADCC) activity in plasma samples prior to infection. These serologic data were analyzed for differences between HIV-exposed uninfected (HEU) and HIV-unexposed (HUU) infants, and for associations with incident infant EBV infection. HEU infants had significantly higher titers than HUU infants for all EBV-binding and neutralizing antibodies measured (P < .01) but not ADCC activity, which was similar between groups. No antibody measure was associated with a decreased risk of EBV acquisition in the cohort. Our findings indicate that in this cohort maternal antibody did not protect infants against EBV infection through viral neutralization. The identification of protective nonneutralizing antibody functions would be invaluable for the development of an EBV vaccine.

Paenibacillus infection with frequent viral coinfection contributes to postinfectious hydrocephalus in Ugandan infants.

Postinfectious hydrocephalus (PIH), which often follows neonatal sepsis, is the most common cause of pediatric hydrocephalus worldwide, yet the microbial pathogens underlying this disease remain to be elucidated. Characterization of the microbial agents causing PIH would enable a shift from surgical palliation of cerebrospinal fluid (CSF) accumulation to prevention of the disease. Here, we examined blood and CSF samples collected from 100 consecutive infant cases of PIH and control cases comprising infants with non-postinfectious hydrocephalus in Uganda. Genomic sequencing of samples was undertaken to test for bacterial, fungal, and parasitic DNA; DNA and RNA sequencing was used to identify viruses; and bacterial culture recovery was used to identify potential causative organisms. We found that infection with the bacterium Paenibacillus, together with frequent cytomegalovirus (CMV) coinfection, was associated with PIH in our infant cohort. Assembly of the genome of a facultative anaerobic bacterial isolate recovered from cultures of CSF samples from PIH cases identified a strain of Paenibacillus thiaminolyticus This strain, designated Mbale, was lethal when injected into mice in contrast to the benign reference Paenibacillus strain. These findings show that an unbiased pan-microbial approach enabled characterization of Paenibacillus in CSF samples from PIH cases, and point toward a pathway of more optimal treatment and prevention for PIH and other proximate neonatal infections.

Markers of Environmental Enteric Dysfunction Are Associated with Poor Growth and Iron Status in Rural Ugandan Infants

ABSTRACTBackgroundEnvironmental enteric dysfunction (EED), characterized by altered intestinal permeability/inflammation, microbial translocation, and systemic inflammation (SI), may be a significant contributor to micronutrient deficiencies and poor growth in infants from low-resource settings.ObjectiveWe examined associations among EED, SI, growth, and iron status at 6 mo of age.MethodsWe performed a cross-sectional analysis of 6-mo-old infants (n = 548) enrolled in a Ugandan birth-cohort study (NCT04233944). EED was assessed via serum concentrations of anti-flagellin and anti- LPS immunoglobulins (Igs); SI was assessed via serum concentrations of ɑ1-acid glycoprotein (AGP) and C-reactive protein (CRP); iron status was assessed via serum concentrations of hemoglobin (Hb), soluble transferrin receptor (sTfR), and ferritin. Associations were assessed using adjusted linear regression analysis.ResultsAt 6 mo, ∼35% of infants were stunted [length-for-age z score (LAZ) < −2] and ∼53% were anemic [hemoglobin (Hb) <11.0 g/dL]. Nearly half (∼46%) had elevated AGP (>1 g/L) and ∼30% had elevated CRP (>5 mg/L). EED and SI biomarkers were significantly correlated (r = 0.142–0.193, P < 0.001 for all). In adjusted linear regression models, which included adjustments for SI, higher anti-flagellin IgA, anti-LPS IgA, and anti-LPS IgG concentrations were each significantly associated with lower LAZ [β (95% CI): −0.21 (−0.41, 0.00), −0.23 (−0.44, −0.03), and −0.33 (−0.58, −0.09)]. Furthermore, higher anti-flagellin IgA, anti-flagellin IgG, and anti-LPS IgA concentrations were significantly associated with lower Hb [β (95% CI): −0.24 (−0.45, −0.02), −0.58 (−1.13, 0.00), and −0.26 (−0.51, 0.00)] and higher anti-flagellin IgG and anti-LPS IgG concentrations were significantly associated with higher sTfR [β (95% CI): 2.31 (0.34, 4.28) and 3.13 (0.75, 5.51)].ConclusionsEED is associated with both low LAZ and iron status in 6-mo-old infants. Further research on the mechanisms by which EED affects growth and micronutrient status is warranted.

Markers of Environmental Enteric Dysfunction Are Associated with Poor Growth and Iron Status in Rural Ugandan infants

Abstract Objectives Environmental enteric dysfunction (EED), characterized by altered intestinal permeability/inflammation, microbial translocation, and systemic inflammation (SI), may be a significant contributor to poor growth and micronutrient deficiencies in infants from low-resource setting. The objective of this study was to examine relationships among EED, SI, growth, and iron status in a sample of 6-months old infants from rural Uganda. Methods We performed a cross-sectional analysis using a subset of infants (n = 548) enrolled in a birth cohort study conducted in 16 sub-counties across northern and southwestern Uganda. EED was assessed via serum levels of antibodies to the bacterial components flagellin and lipopolysaccharide (LPS); SI was assessed via serum levels of alpha(1)-acid glycoprotein (AGP) and C-reactive protein (CRP); iron status was assessed via serum levels of hemoglobin (Hb), soluble transferrin receptor (sTfR), and ferritin. Associations were assessed using adjusted linear regression analysis. Results At 6 months, ∼35% of infants were stunted (LAZ &amp;lt; −2), and ∼53% were anemic (Hb &amp;lt; 11.0 g/dL). Nearly half (∼46%) had elevated AGP (&amp;gt;1 g/L) and ∼30% had elevated CRP (&amp;gt;5 mg/L). EED biomarkers were significantly correlated with SI biomarkers (r = 0.142–0.193, P &amp;lt; 0.001 for all). In adjusted linear regression models, which included adjustments for SI, higher anti-flagellin IgA, anti-LPS IgA, and anti-LPS IgG levels were significantly associated with lower LAZ [β: −0.21 (95% CI: −0.41, 0.00), β: −0.23 (95% CI: −0.44, −0.03), and β: −0.33 (95% CI: −0.58, −0.09)]. Furthermore, higher anti-flagellin IgA, anti-flagellin IgG, and anti-LPS IgA levels were significantly associated with lower Hb levels [β: −0.24 (95% CI: −0.45, −0.02), β: −0.58 (95% CI: −1.13, 0.00), and β: −0.26 (95% CI: −0.51, 0.00)]; higher anti-flagellin IgG and anti-LPS IgG levels were significantly associated with higher sTfR levels [β: 2.31 (95% CI: 0.34, 4.28) and β: 3.13 (95% CI: 0.75, 5.51)]. Conclusions Independent of SI, EED is associated with both low LAZ and iron status in 6-months old infants. Further research on the mechanisms by which EED affects growth and micronutrient status is warranted. Funding Sources USAID, award AID-OAA-L-10–00006 to the Friedman School of Nutrition Science and Policy at Tufts University. CD was supported in part by NIH grants K24DK104676 and 2P30 DK040561.

Maternal Latent Mycobacterium tuberculosis Does Not Affect the Infant Immune Response Following BCG at Birth: An Observational Longitudinal Study in Uganda.

Background: BCG has low efficacy in tropical countries. We hypothesized that maternal latent Mycobacterium tuberculosis (M.tb) infection (LTBI) results in fetal tolerance to mycobacterial antigens and impaired responses to BCG immunization.Methods: We enrolled 132 LTBI-positive and 150 LTBI-negative mothers and their babies in Entebbe, Uganda. Infants were BCG-immunized at birth. Cord blood and samples at weeks 1, 4, 6, 10, 14, 24, and 52 were analyzed for cytokine/chemokine responses to M.tb antigens by Luminex 17-plex assay in 6-day whole blood cultures and antibody responses by ELISA. Of the 17 Luminex analytes, seven (IL-2, IL-5, IL-10, IL-13, IL-17A, TNF, and IFN-γ) were included in the main analysis as they were considered most likely to represent T cell responses. Immune sensitization was defined as a detectable cord blood cytokine response to PPD for any of the seven cytokines. Patterns of cytokine and antibody responses were compared between infants of mothers with and without LTBI using linear mixed models adjusting for confounders.Results: Most infants (73%) were sensitized in utero to M.tb antigens, with no overall difference seen between infants born to mothers with or without LTBI. Patterns of post-BCG cytokine and antibody responses to mycobacterial antigens were similar between the two infant groups.Conclusions: Our data do not support the hypothesis that maternal LTBI results in an impaired response to BCG immunization, in Ugandan infants. BCG vaccination at or shortly after birth is likely to be beneficial to all infants, irrespective of maternal LTBI status.