Pattern of Infectious Morbidity in HIV-Exposed Uninfected Infants and Children

KIR2DL1 gene is a surrogate marker of protection against infection-related hospitalization among HIV-1 unexposed versus exposed uninfected infants in Cameroon

BACKGROUND

HIV-exposed uninfected infants (HEU) appear more vulnerable to infections compared to their HIV-unexposed uninfected (HUU) peers, generally attributed to poor passive immunity acquired from the mother. This may be due to some genetic factors that could alter the immune system. We thus sought to determine the distribution of Killer Cell Immunoglobulin-Like Receptors (KIRs) genes in HEU versus HUU and study their associations with the occurrence of infection-related hospitalization.

METHODS

A cohort study was conducted from May 2019 to April 2020 among HEU and HUU infants, including their follow-up at weeks 6, 12, 24, and 48, in reference pediatric centers in Yaoundé-Cameroon. The infant HIV status and infections were determined. A total of 15 KIR genes were investigated using the sequence-specific primer polymerase chain reaction (PCR-SSP) method. The KIR genes that were significantly associated with HIV-1 status (HEU and HUU) were analyzed for an association with infection-related hospitalizations. This was only possible if, and to the extent that, infection-related hospitalizations varied significantly according to status. Multivariate logistic regression analyses were conducted to determine the association between KIR gene content variants and HIV status, while considering a number of potential confounding factors. Furthermore, the risk was quantified using relative risk, odds ratio, and a 95% confidence interval. The Fisher exact test was employed to compare the frequency of occurrences. A p-value of less than 0.05 was considered statistically significant.

RESULTS

In this cohort, a total of 66 infants participated, but only 19 acquired infections requiring hospitalizations (14.81%, 04/27 HUU and 38.46%, 15/39 HEU, p = 0.037). At week 48 (39 HEU and 27 HUU), the relative risk (RR) for infection-related hospitalizations was 2.42 (95% CI: 1.028-5.823) for HEU versus HUU with OR 3.59 (1.037-12.448). KIR2DL1 gene was significantly underrepresented in HEU versus HUU (OR = 0.183, 95%CI: 0.053-0.629; p = 0.003), and the absence of KIR2DL1 was significantly associated with infection-related hospitalization (p < 0.001; aOR = 0.063; 95%CI: 0.017-0.229).

CONCLUSION

Compared to HUU, the vulnerability of HEU is driven by KIR2DL1, indicating the protective role of this KIR against infection and hospitalizations.

COVID-19 in children: Clinical presentation and hospital course at a district hospital in South Africa

Limited data exist on South African children hospitalised with COVID-19 in district hospitals. We describe the presentation and outcomes of children admitted to a level 1 and 2 hospital and compare this with children admitted to a level 2 and 3 hospital.

Contribution

This study highlights that young age is an important risk factor for hospitalisation with severe COVID-19. Infants with HIV exposure and prematurity are disproportionately represented among admissions. Furthermore, we notice a high number of children with current or new tuberculosis confirming the interplay between viral infections and childhood tuberculosis.

Peripartum mobility and maternal/child separation among women living with HIV in South Africa

This prospective cohort study investigated the mobility patterns of 200 pregnant and postpartum women living with HIV in South Africa. Participants were enrolled during their third trimester from routine antenatal care near Cape Town, South Africa, and followed for six months postpartum. Quantitative data were collected at enrollment and follow-up. Mobility (self-reported) was common among the participants, despite the brief study period and the concurrent COVID-19 pandemic. While most reported stability in their current residence, 71% had a second main residence, primarily in the Eastern Cape (EC). Participants had a median of two lifetime moves, motivated by work, education, and family life. During the study period, 20% of participants met the study definition of travel (>7 days and >50 km), with trips predominantly to the EC, lasting a median duration of 30 days. Over one-third of participants with other living children reported that these children lived apart from them, with the mother's family being primary caregivers. These findings emphasize the need for targeted interventions to support continuity of care for mobile populations, particularly peripartum women living with HIV. The study contributes valuable insights into mobility dynamics and highlights unique barriers faced by this population, contributing to improved HIV care in resource-limited settings.

Premature skewing of T cell receptor clonality and delayed memory expansion in HIV-exposed infants

While preventing vertical HIV transmission has been very successful, HIV-exposed uninfected infants (iHEU) experience an elevated risk to infections compared to HIV-unexposed and uninfected infants (iHUU). Here we present a longitudinal multimodal analysis of infant immune ontogeny that highlights the impact of HIV/ARV exposure. Using mass cytometry, we show alterations in T cell memory differentiation between iHEU and iHUU being significant from week 15 of life. The altered memory T cell differentiation in iHEU was preceded by lower TCR Vβ clonotypic diversity and linked to TCR clonal depletion within the naïve T cell compartment. Compared to iHUU, iHEU had elevated CD56loCD16loPerforin+CD38+CD45RA+FcεRIγ+ NK cells at 1 month postpartum and whose abundance pre-vaccination were predictive of vaccine-induced pertussis and rotavirus antibody responses post 3 months of life. Collectively, HIV/ARV exposure disrupted the trajectory of innate and adaptive immunity from birth which may underlie relative vulnerability to infections in iHEU.

Exposure to HIV alters the composition of maternal microchimeric T cells in infants

Infants exposed to HIV but uninfected (iHEU) display altered cellular immunity and are at increased risk of infection through poorly understood mechanisms. We previously reported that iHEU have lower levels of maternal microchimerism (MMc), maternal cells transferred to the offspring in utero/during breastfeeding. We evaluated MMc levels in T cell subsets in iHEU and HIV unexposed infants (iHU) to determine whether a selective deficiency in MMc may contribute to altered cellular immunity. Across all infants, MMc levels were highest in CD8+ T cells; however, the level of MMc in the CD8 T cell subset was significantly lower in iHEU compared to iHU.

Disturbances in the IgG Antibody Profile in HIV-Exposed Uninfected Infants Associated with Maternal Factors

Over the last 20 years, the incidence of vertical HIV transmission has decreased from 25%-42% to less than 1%. Although there are no signs of infection, the health of HIV-exposed uninfected (HEU) infants is notoriously affected during the first months of life, with opportunistic infections being the most common disease. Some studies have reported effects on the vertical transfer of antibodies, but little is known about the subclass distribution of these antibodies. We proposed to evaluate the total IgG concentration and its subclasses in HIV+ mothers and HEU pairs and to determine which maternal factors condition their levels. In this study, plasma from 69 HEU newborns, their mothers, and 71 control pairs was quantified via immunoassays for each IgG isotype. Furthermore, we followed the antibody profile of HEUs throughout the first year of life. We showed that mothers present an antibody profile characterized by high concentrations of IgG1 and IgG3 but reduced IgG2, and HEU infants are born with an IgG subclass profile similar to that of their maternal pair. Interestingly, this passively transferred profile could remain influenced even during their own antibody production in HEU infants, depending on maternal conditions such as CD4+ T-cell counts and maternal antiretroviral treatment. Our findings indicate that HEU infants exhibit an altered IgG subclass profile influenced by maternal factors, potentially contributing to their increased susceptibility to infections.

Clinical and immunological outcomes of HIV-exposed uninfected and HIV-unexposed uninfected children in the first 24 months of life in Western Kenya

BACKGROUND

Previous studies show increased morbidity in children who are HIV-exposed but uninfected (HEU) compared to children who are HIV-unexposed uninfected (HUU). We sought to evaluate the effects of prenatal HIV exposure on clinical and immunological outcomes in the first 24 months of life.

METHODS

Eighty-five HEU and 168 HUU children from Kenya were followed from birth to 24 months. All mothers living with HIV received combination antiretroviral therapy. Children who were HEU received standard-of-care cotrimoxazole prophylaxis through 18 months. Episodes of acute illness were identified through a combination of active and passive follow up. Trajectories of plasma cytokines, vaccine-specific antibodies, and antimalarial antibodies were examined.

RESULTS

Children who were HEU and children who were HUU had similar growth curves. Children who were HEU had lower rates of malaria (rate ratio 0.54, 95% CI 0.38, 0.77) and respiratory illness (rate ratio 0.80, 95% CI 0.68, 0.93). Trajectories of plasma cytokines and vaccine-specific antibodies were similar in children who were HEU and HUU. There were subtle differences in antimalarial antibody dynamics, in which children who were HEU had overall lower antibody levels against five of the 14 malaria antigens tested.

CONCLUSIONS

Children who were HEU and born to optimally treated mothers living with HIV had similar growth characteristics and immune profiles compared to children who were HUU. Children who were HEU had reduced risk for malaria and respiratory illness, which may be secondary to cotrimoxazole prophylaxis.

Maternal immunization in women living with HIV

Thanks to widespread use of antiretroviral therapy worldwide, women living with HIV (WLWH) are becoming pregnant and giving birth to HIV-exposed but uninfected (HEU) newborns. Both pregnancy and HIV infection-related factors such as low CD4+ T-cell count or uncontrolled viral load increase the risk of severe infections such as influenza, COVID-19, and others, making maternal immunization a valuable tool to decrease maternal morbidity among WLWH. Vaccines administered during pregnancy may also benefit the health of HEU infants. Indeed, HEU infants suffer from higher risk of morbidity of infectious origin, including respiratory syncytial virus (RSV), group B streptococcus (GBS), pneumococcus and pertussis infections. Maternal pertussis immunization is recommended in various high-income countries but not in many low-middle income countries where HIV prevalence is higher. GBS and RSV vaccines to be administered during pregnancy are currently in late-phase clinical trials in HIV-uninfected women and could represent a valuable tool to decrease morbidity during infancy. Decreased transfer of vaccine-specific IgG, accelerated waning of vaccine-induced antibody responses, linked to persistent maternal immune activation, and blunting of infant immune response to vaccines could hamper vaccine effectiveness among WLWH and HEU infants. Vaccine hesitancy could limit benefits of maternal immunization and strategies to tackle vaccine hesitancy should be part of HIV routine care. The aim of this review is to summarize the current knowledge regarding the immunogenicity and efficacy of available and upcoming vaccines recommended during pregnancy of WLWH.

Risk and rates of hospitalisation in young children: A prospective study of a South African birth cohort

Children in sub-Saharan Africa (SSA) are disproportionately affected by morbidity and mortality. There is also a growing vulnerable population of children who are HIV-exposed uninfected (HEU). Understanding reasons and risk factors for early-life child hospitalisation will help optimise interventions to improve health outcomes. We investigated hospitalisations from birth to two years in a South African birth cohort study. Mother-child pairs in the Drakenstein Child Health Study were followed from birth to two years with active surveillance for hospital admission and investigation of aetiology and outcome. Incidence, duration, cause, and factors associated with child hospitalisation were investigated, and compared between HEU and HIV-unexposed uninfected (HUU) children. Of 1136 children (247 HEU; 889 HUU), 314 (28%) children were hospitalised in 430 episodes despite >98% childhood vaccination coverage. The highest hospitalisation rate was from 0-6 months, decreasing thereafter; 20% (84/430) of hospitalisations occurred in neonates at birth. Amongst hospitalisations subsequent to discharge after birth, 83% (288/346) had an infectious cause; lower respiratory tract infection (LRTI) was the most common cause (49%;169/346) with respiratory syncytial virus (RSV) responsible for 31% of LRTIs; from 0-6 months, RSV-LRTI accounted for 22% (36/164) of all-cause hospitalisations. HIV exposure was associated with increased incidence rates of hospitalisation in infants (IRR 1.63 [95% CI 1.29-2.05]) and longer hospital admission (p = 0.004). Prematurity (HR 2.82 [95% CI 2.28-3.49]), delayed infant vaccinations (HR 1.43 [95% CI 1.12-1.82]), or raised maternal HIV viral load in HEU infants were risk factors for hospitalisation; breastfeeding was protective (HR 0.69 [95% CI 0.53-0.90]). In conclusion, children in SSA experience high rates of hospitalisation in early life. Infectious causes, especially RSV-LRTI, underly most hospital admissions. HEU children are at greater risk of hospitalisation in infancy compared to HUU children. Available strategies such as promoting breastfeeding, timely vaccination, and optimising antenatal maternal HIV care should be strengthened. New interventions to prevent RSV may have additional impact in reducing hospitalisation.

Morbidity and Mortality of HIV-Exposed Uninfected Infants in a Tertiary Referral Facility in Yaoundé, Cameroon

Background and Objective

Following the recorded progress in the prevention of mother-to-child transmission of HIV in Yaoundé, Cameroon, the proportion of HIV-exposed infants who are uninfected (UIH) is increasing. These children are subject to infectious and non-infectious fragility. The purpose of this study was to assess infectious morbidity and mortality rates among UIH in Yaoundé, Cameroon.

Methods

We conducted a retrospective cohort study. Infants were included in the study and defined as the study subjects if they were between the ages of 24 months or younger, if they were born to HIV-positive mothers, and if they were confirmed to be HIV-negative. The main study outcomes were morbidity rate (defined as infectious, clinical events that required consultation or hospitalization) and death. Data were entered and saved in the Census and Survey Processing System (Cspro) 7.3. Statistical analyses were performed in R Software 3.6.2. The significance level was set at 0.05.

Results

In total, 240 subjects were recruited of whom 53.3% were males. Most of the HIV-positive mothers (95.7%) had used combination antiretroviral (ARV) therapy for at least four weeks during pregnancy. Among the subjects, 93.2% received ARV prophylaxis, 68.7% were exclusively breastfed for six months, 94.7% were fully vaccinated, and 60.6% had received cotrimoxazole up to the detection of the non-infection. Overall, the morbidity rate stood at 34.2%. The incidence of morbidity was 3 per 1,000 child months of the follow-up. The main pathologies were acute respiratory infections (60.79%) and malaria (17.65%). Three deaths were recorded, representing an overall mortality rate of 1.25% for an incidence of 1.1 per 1,000 child months of the follow-up (FU). Clinical events were more frequent in mothers diagnosed with HIV during pregnancy under the azidothymidine (AZT) + lamivudine (3TC) + névirapine (NVP) -based protocol (odds ratio of 3.83 [1.09-14.45; p = 0.039]). Morbidity was also higher for the follow-up periods of less than six months.

Conclusion and Global Health Implications

The overall mortality rate among UIH was low. However, the morbidity rate was considerably higher. Emphasis should be focused on in-care retention for up to 24 months for all UIH, which should include monitoring of HIV-infected mothers prior to pregnancy.

Bifidobacterium infantis associates with T cell immunity in human infants and is sufficient to enhance antigen-specific T cells in mice

Bacille Calmette-Guerin (BCG) vaccine can elicit good TH1 responses in neonates. We hypothesized that the pioneer gut microbiota affects vaccine T cell responses. Infants who are HIV exposed but uninfected (iHEU) display an altered immunity to vaccination. BCG-specific immune responses were analyzed at 7 weeks of age in iHEU, and responses were categorized as high or low. Bifidobacterium longum subsp. infantis was enriched in the stools of high responders, while Bacteroides thetaiotaomicron was enriched in low responders at time of BCG vaccination. Neonatal germ-free or SPF mice orally gavaged with live B. infantis exhibited significantly higher BCG-specific T cells compared with pups gavaged with B. thetaiotaomicron. B. infantis and B. thetaiotaomicron differentially affected stool metabolome and colonic transcriptome. Human colonic epithelial cells stimulated with B. infantis induced a unique gene expression profile versus B. thetaiotaomicron. We thus identified a causal role of B. infantis in early-life antigen-specific immunity.

Strengthening the evidence to improve health outcomes of children with perinatal HIV exposure

INTRODUCTION

The number of children exposed to HIV and possibly to antiretroviral therapy (ART) in utero and during breastfeeding and are uninfected (HEU) globally will continue to increase from the estimated 15.9 million in 2021.

DISCUSSION

There are still significant gaps in our understanding of the impact of HIV and/or ART exposure in children who are HEU, in terms of prevalence/incidence and severity on health and wellbeing, and long after exposure has ended. While there have been substantial programmatic efforts to support the elimination of vertical transmission of HIV, additional rigorous research is needed to better understand the biological, (psycho)social and structural factors contributing to optimal health for populations who are HEU. Furthermore, the best approaches to address and study the gaps in understanding also need to be explored. Given the scope of the problem including the large numbers of affected people as well as the often limited and competing in-country resources for populations affected by HIV, novel methodologies, including multi-level approaches and advanced analytics, need to be considered.

CONCLUSIONS

A growing population of children who are HEU are maturing into adolescence and young adulthood. Research to advance understanding of the possible negative long-term effects of HIV and/or ART exposure in these youth is supported by the US National Institutes of Health. Both large epidemiological studies and smaller more comprehensive cohort studies may be required to address the complexity of the issue. Integrating both types of studies could allow the establishment of more reliable and validated predictions of which youth who are HEU are at the highest risk for specific negative health outcomes, such as mental health and neurocognitive disorders, and which interventional approaches may be most successful to address specific deficits both in terms of prevention and treatment. Finally, these goals can be more rapidly achieved with data science efforts, data harmonisation between studies and with sustainable data-sharing practices. It is important to expand the commitment to research to identify biological, social and structural drivers, to develop screening tools, and impactful and contextually appropriate interventions to address the health and wellbeing of children who are HEU from birth through adulthood.

Setting the research agenda: involving parents in research on children who are HIV-free

INTRODUCTION

There is growing interest in health, developmental and survival outcomes of children who are born HIV-free to women living with HIV (children born HIV-free). To date, the research agenda has been largely determined by researchers, funders and policy makers, with limited involvement of parents, who are key stakeholders. Researchers at UCL Great Ormond Street Institute of Child Health in partnership with community-based organisation 4M Network of Mentor Mothers conducted two workshops with parents in March 2022 to establish research priorities for children born HIV-free, and key considerations for methodological approaches both to research and engagement with the affected communities.

DISCUSSION

When exploring research on children born HIV-free, we consider the following: what aspects of current research are aligned with women and parents' priorities, what is missing and what approaches would be preferred. A holistic approach to research on children born HIV-free should be prioritised, focussing on a breadth of outcomes and how they intersect. Secondary use of existing data sources should be maximised to facilitate this, with a view of monitoring the long-term effects of fetal antiretroviral drug exposure alongside other key health and developmental outcomes. Involving and engaging with parents, and children where possible, must be at the heart of research design to maximise relevance and impact of findings for the affected communities. Potential barriers to engaging with individuals who were children born HIV-free include parental disclosure and individuals not identifying as a child born HIV-free to a mother living with HIV. Stigma-free language must be incorporated into the vocabulary of researchers and other stakeholders, avoiding reference to exposure; we propose the term "children born HIV-free."

CONCLUSIONS

Mothers and parents living with HIV should be involved in research about their children born HIV-free and are key in identifying research priorities so that findings may translate into an impact on their children's health and wellbeing. Meaningful involvement of women living with HIV through trusted community partners is an effective mechanism by which to elicit views on research about their children.

Pulmonary Function in HIV-Infected Children at a Tertiary Care Hospital in North India: A Prospective Cross-Sectional Study

Background The global burden of HIV remains significant, particularly in India. Antiretroviral therapy (ART) has improved outcomes for children with HIV, yet understanding the virus's impact on respiratory health is essential. Pulmonary complications, common in HIV-infected adults, are poorly understood in children. Despite India's high HIV prevalence, data on pediatric lung function are lacking. This study aims to evaluate spirometry-based pulmonary function in perinatally HIV-infected children, exploring associations with disease severity, immune status, and other factors. Methods This prospective cross-sectional study conducted in a North Indian tertiary care hospital aimed to assess pulmonary function using spirometry in children (6-18 years) with HIV infection. Ethical approval and informed consent were secured. Data on demographics, clinical history, CD4+ T-cell counts, and viral load were collected. Certified respiratory therapists performed spirometry using standardized protocols. Descriptive statistics were computed, and differences in pulmonary function based on CD4+ T-cell counts, viral load, and opportunistic infection were analyzed. The study adhered to ethical guidelines and maintained participants' confidentiality. Results This cross-sectional study enrolled 57 children (mean age 13.6±3.2 years) with HIV infection. Age distribution was <9 years (24.6%), 9-11 years (28.1%), and >11 years (47.4%). Males constituted 56.1%. The mean BMI was 15.92±2.78 kg/m². HIV viral load (87.23±56.28 copies/μL) and CD4 count (1146.32±103.98 cells/mm³) were recorded. ART duration averaged 6.21±1.36 years. Viral load groups were <1 (52.6%), 1-1000 (26.3%), and >1000 copies/μL (21.1%). CD4 categories were >500 cells/mm³ (47.4%), 200-499 (42.1%), and <200 cells/mm³ (10.5%). Spirometry showed 71.9% normal and 28.1% abnormal (mild/moderate obstruction: 18.8%, mild/moderate restriction: 81.3%). No significant spirometric differences were observed among CD4 or viral load groups (p>0.05), nor with opportunistic infections (p>0.05). Conclusion This study reveals complex associations between spirometric parameters and CD4 count, viral load, and opportunistic infections in children with HIV. Further research, including longitudinal studies, is needed to unravel the intricate interplay and improve management strategies for this population.

Mild/asymptomatic COVID-19 in unvaccinated pregnant mothers impairs neonatal immune responses

Maternal SARS-CoV-2 infection triggers placental inflammation and alters cord blood immune cell composition. However, most studies focus on outcomes of severe maternal infection. Therefore, we analyzed cord blood and chorionic villi from newborns of unvaccinated mothers who experienced mild/asymptomatic SARS-CoV-2 infection during pregnancy. We investigated immune cell rewiring using flow cytometry, single-cell RNA sequencing, and functional readouts using ex vivo stimulation with TLR agonists and pathogens. Maternal infection was associated with increased frequency of memory T and B cells and nonclassical monocytes in cord blood. Ex vivo T and B cell responses to stimulation were attenuated, suggesting a tolerogenic state. Maladaptive responses were also observed in cord blood monocytes, where antiviral responses were dampened but responses to bacterial TLRs were increased. Maternal infection was also associated with expansion and activation of placental Hofbauer cells, secreting elevated levels of myeloid cell-recruiting chemokines. Moreover, we reported increased activation of maternally derived monocytes/macrophages in the fetal placenta that were transcriptionally primed for antiviral responses. Our data indicate that even in the absence of vertical transmission or symptoms in the neonate, mild/asymptomatic maternal COVID-19 altered the transcriptional and functional state in fetal immune cells in circulation and in the placenta.

Clinical and Immunological Outcomes of HIV-Exposed Uninfected and HIV-Unexposed Uninfected Children in the First 24 Months of Life in Western Kenya

Background

Previous studies show increased morbidity in children who are HIV-exposed but uninfected (HEU) compared to children who are HIV-unexposed uninfected (HUU). We sought to evaluate the effects of prenatal HIV exposure on clinical and immunological outcomes in the first 24 months of life.

Methods

Eighty-five HEU and 168 HUU children from Kenya were followed from birth to 24 months. All mothers with HIV received combination antiretroviral therapy. HEU children received standard-of-care cotrimoxazole prophylaxis through 18 months. Episodes of acute illness were identified through a combination of active and passive follow up. Trajectories of plasma cytokines, vaccine-specific antibodies, and antimalarial antibodies were examined.

Results

HEU and HUU children had similar growth curves. HEU children had lower rates of malaria and respiratory illness. Trajectories of plasma cytokines and vaccine-specific antibodies were similar in HEU and HUU children. There were subtle differences in antimalarial antibody dynamics, in which HEU children had overall lower antibody levels against five of the 14 malaria antigens tested.

Conclusions

HEU children born to optimally treated mothers living with HIV had similar growth characteristics and immune profiles compared to HUU children. HEU children had reduced risk for malaria and respiratory illness, which may be secondary to cotrimoxazole prophylaxis.

Risk and rates of hospitalisation in young children: a prospective study of a South African birth cohort

Introduction

Children in sub-Saharan Africa (SSA) are disproportionately affected by morbidity and mortality; there is also a growing vulnerable population of children who are HIV-exposed uninfected (HEU). Understanding reasons and risk factors for early-life child hospitalisation will help optimise interventions to improve health outcomes. We investigated hospitalisations from birth to two years in a South African birth cohort.

Methods

Mother-child pairs in the Drakenstein Child Health Study were followed from birth to two years with active surveillance for hospital admission and investigation of aetiology and outcome. Incidence, duration, cause, and factors associated with child hospitalisation were investigated, and compared between HEU and HIV-unexposed uninfected (HUU) children.

Results

Of 1136 children (247 HEU; 889 HUU), 314 (28%) children were hospitalised in 430 episodes despite >98% childhood vaccination coverage. The highest hospitalisation rate was from 0-6 months, decreasing thereafter; 20% (84/430) of hospitalisations occurred in neonates at birth. Amongst hospitalisations subsequent to discharge after birth, 83% (288/346) had an infectious cause; lower respiratory tract infection (LRTI) was the most common cause (49%;169/346) with respiratory syncytial virus (RSV) responsible for 31% of LRTIs; from 0-6 months, RSV-LRTI accounted for 22% (36/164) of all-cause hospitalisations. HIV exposure was a risk factor for hospitalisation in infants (IRR 1.63 [95% CI 1.29-2.05]) and longer hospital admission (p=0.004). Prematurity (HR 2.82 [95% CI 2.28-3.49]), delayed infant vaccinations (1.43 [1.12-1.82]), or raised maternal HIV viral load in HEU infants were risk factors; breastfeeding was protective (0.69 [0.53-0.90]).

Conclusion

Children in SSA continue to experience high rates of hospitalisation in early life. Infectious causes, especially RSV-LRTI, underly most hospital admissions. HEU children are at particular risk in infancy. Available strategies such as promoting breastfeeding, timely vaccination, and optimising antenatal maternal HIV care should be strengthened. New interventions to prevent RSV may have a large additional impact in reducing hospitalisation.

Human immunodeficiency virus and antiretroviral therapy-mediated immune cell metabolic dysregulation in children born to HIV-infected women: potential clinical implications

Commencing lifelong antiretroviral therapy (ART) immediately following HIV diagnosis (Option B+) has dramatically improved the health of HIV-infected women and their children, with the majority being of HIV-exposed children born uninfected (HEU). This success has led to an increasing population of HIV-infected women receiving ART during pregnancy and children exposed to ART in utero. Nonetheless, a small proportion of children are still infected with HIV (HEI) each year. HEI children suffer from reduced immunocompetence and host-defence, due to CD4+ T lymphocyte depletion, but also dysregulation of other immune cells including CD8+ T lymphocytes, natural killer (NK) cells, macrophages including B lymphocytes. Furthermore, although HEU children are uninfected, altered immune responses are observed and associated with increased vulnerability to infections. The mechanisms underlying immune dysregulation in HEU children remain poorly described. Building on early studies, emerging data suggests that HIV/ART exposure early in life affects cell metabolic function of HEU children. Prenatal HIV/ART exposure has been associated with dysregulation of mitochondria, including impaired DNA polymerase activity. Furthermore, dysregulation of oxidative phosphorylation (OXPHOS) causes a decreased generation of adenosine triphosphate (ATP) and increased production of reactive oxygen species (ROS), resulting in oxidative stress. These altered metabolic processes can affect immune cell viability and immune responses. Recent studies have indicated that immune-metabolic dysregulation may contribute to HIV-associated pathogenesis and clinical observations associated with HIV and ART exposure in HEU/HEI children. Given the critical role metabolic processes in immune cell functioning, immune-metabolic dysregulation in HEU and HEI children may have implications in effective host-defence responses against pathogens, as well as efficacy of standard ART regimens and future novel HIV cure approaches in HEI children. At the same time, targeting metabolic pathways of immune cells may provide safer and novel approaches for HIV cure strategies. Here, we review the current literature investigating immune-metabolic dysregulation in paediatric HIV pathogenesis.

Co-trimoxazole prophylaxis for children who are HIV-exposed and uninfected: a systematic review

INTRODUCTION

Co-trimoxazole prophylaxis is recommended for children born to women with HIV to protect those who acquire HIV from opportunistic infections, severe bacterial infections and malaria. With scale-up of maternal antiretroviral therapy, most children remain HIV-exposed uninfected (HEU) and the benefits of universal co-trimoxazole are uncertain. We assessed the effect of co-trimoxazole on mortality and morbidity of children who are HEU.

METHODS

We performed a systematic review (PROSPERO number: CRD42021215059). We systematically searched MEDLINE, Embase, Cochrane CENTRAL, Global Health, CINAHL Plus, Africa-Wide Information, SciELO and WHO Global Index Medicus for peer-reviewed articles from inception to 4th January 2022 without limits. Ongoing randomized controlled trials (RCTs) were identified through registries. We included RCTs reporting mortality or morbidity in children who are HEU receiving co-trimoxazole versus no prophylaxis/placebo. The risk of bias was assessed using the Cochrane 2.0 tool. Data were summarized using narrative synthesis and findings were stratified by malaria endemicity.

RESULTS

We screened 1257 records and included seven reports from four RCTs. Two trials from Botswana and South Africa of 4067 children who are HEU found no difference in mortality or infectious morbidity in children randomized to co-trimoxazole prophylaxis started at 2-6 weeks of age compared to those randomized to placebo or no treatment, although event rates were low. Sub-studies found that antimicrobial resistance was higher in infants receiving co-trimoxazole. Two trials in Uganda investigating prolonged co-trimoxazole after breastfeeding cessation showed protection against malaria but no other morbidity or mortality differences. All trials had some concerns or a high risk of bias, which limited the certainty of evidence.

DISCUSSION

Studies show no clinical benefit of co-trimoxazole prophylaxis in children who are HEU, except to prevent malaria. Potential harms were identified for co-trimoxazole prophylaxis leading to antimicrobial resistance. The trials in non-malarial regions were conducted in populations with low mortality potentially reducing generalizability to other settings.

CONCLUSIONS

In low-mortality settings with few HIV transmissions and well-performing early infant diagnosis and treatment programmes, universal co-trimoxazole may not be required.

Feasibility Study of a Powder-Based Supplement Intervention for a future Synbiotic Trial in Breastfed Children from South Africa

Background

Children who are HIV-exposed uninfected (HEU), i.e., born to mothers living with HIV despite not acquiring HIV infection themselves, have increased morbidity and mortality. Data suggests that the breastmilk profile, and more specifically human milk oligosaccharide (HMO) composition, differ by maternal HIV status and may partly help explain this increased risk. We are currently conducting an HMO-based synbiotic randomized trial in breastfed children HEU, the MIGH-T MO study (ClinicalTrials.gov Identifier: NCT05282485), to assess the impact on health outcomes of children HEU. Here, we report our experience from a study of the feasibility and acceptability of a powder-based intervention given to breastfeeding children, conducted prior to the initiation of MIGH-T MO.

Methods

10 mothers living with HIV and their breastfeeding children HEU accessing care at Tygerberg Hospital, in Cape Town, South Africa were enrolled. A powder-based product, potato maltodextrin, was mixed with expressed breast milk and administered to the infants daily for 4 weeks. Data on feasibility, acceptability, adherence, and health outcomes were assessed at the enrollment visit and at the 4 week visit, along with weekly telephone calls.

Results

10 mother-infant pairs were enrolled in this study, with infant age ranging from 6-20 months of age. Among the mothers who met the eligibility criteria, all of them enrolled into the study suggesting high acceptability. While there was some Ioss-to-follow-up after the first visit, among the mothers who remained, there were no major feasibility concerns related to study procedures, product administration, adherence, tolerance, and health outcome assessment.

Conclusion

Our pilot study demonstrated that a powder-based intervention for breastfeeding children HEU in South Africa is acceptable and feasible. This suggests potential feasibility and acceptability for other larger studies, including our ongoing MIGH-T MO study, that use similar powder-based interventions such as probiotics, prebiotics, or synbiotics, in breastfed infants from similar settings.

Mild/Asymptomatic Maternal SARS-CoV-2 Infection Leads to Immune Paralysis in Fetal Circulation and Immune Dysregulation in Fetal-Placental Tissues

Few studies have addressed the impact of maternal mild/asymptomatic SARS-CoV-2 infection on the developing neonatal immune system. In this study, we analyzed umbilical cord blood and placental chorionic villi from newborns of unvaccinated mothers with mild/asymptomatic SARSCoV-2 infection during pregnancy using flow cytometry, single-cell transcriptomics, and functional assays. Despite the lack of vertical transmission, levels of inflammatory mediators were altered in cord blood. Maternal infection was also associated with increased memory T, B cells, and non-classical monocytes as well as increased activation. However, ex vivo responses to stimulation were attenuated. Finally, within the placental villi, we report an expansion of fetal Hofbauer cells and infiltrating maternal macrophages and rewiring towards a heightened inflammatory state. In contrast to cord blood monocytes, placental myeloid cells were primed for heightened antiviral responses. Taken together, this study highlights dysregulated fetal immune cell responses in response to mild maternal SARS-CoV-2 infection during pregnancy.

Unique Profile of Inflammation and Immune Activation in Pregnant People With HIV in the United States

BACKGROUND

Little is known about inflammation/immune activation during pregnancy in people with HIV (PWH) and growth in their children who are HIV-exposed and uninfected (CHEU).

METHODS

Using data from the Pediatric HIV/AIDS Cohort Study and an HIV-seronegative comparison group, we assessed associations of (1) HIV status, mode of HIV acquisition (perinatally vs nonperinatally acquired), and type of antiretroviral therapy (ART) with inflammation/immune activation in pregnancy; and (2) inflammation/immune activation in pregnancy with growth of CHEU at 12 months. Interleukin 6 (IL-6), high-sensitivity C-reactive protein (hs-CRP), soluble(s) TNF-α receptor 1 and 2 (sTNFR1, sTNFR2), sCD14, and sCD163 were measured between 13 and 27 weeks' gestation. Linear regression models were fit to estimate differences between groups for each log-transformed biomarker, adjusted for confounders.

RESULTS

Pregnant PWH (188 total, 39 perinatally acquired, 149 nonperinatally acquired) and 76 HIV-seronegative persons were included. PWH had higher IL-6, sTNFR1, sCD14, and sCD163 and lower sTNFR2 compared to HIV-seronegative persons in adjusted models. Among PWH, sCD163 was higher in those with perinatally versus nonperinatally acquired HIV and on PI-based versus INSTI-based ART. Higher maternal concentrations of IL-6, sTNFR2, and hs-CRP were associated with poorer growth at 12 months.

CONCLUSIONS

Maternal HIV status is associated with a distinct profile of inflammation/immune activation during pregnancy, which may influence child growth.

Longitudinal comparison of insulin resistance and dyslipidemia in children with and without perinatal HIV infection in South Africa

INTRODUCTION

HIV infection is associated with insulin resistance and dyslipidaemia driven by HIV-associated immune dysregulation and antiretroviral therapy (ART). Children living with perinatally acquired HIV (CHIV) face many decades of exposure to these factors. We evaluated the longitudinal trajectory of insulin resistance and dyslipidaemia in CHIV and HIV-exposed uninfected children (CHEU), compared with children HIV-unexposed (CHU).

METHODS

Four hundred and eighty-five children (141 CHIV, 169 CHEU, 175 CHU) aged 5-16 years, previously part of CHER and P1060 trials, were followed annually at Tygerberg Children's Hospital, South Africa. The primary outcome was Homeostatic Model Assessment of Insulin Resistance (HOMA-IR). Secondary outcomes included low-density lipoprotein (LDL) cholesterol, triglyceride-to-HDL ratio, android fat mass and SBP. Outcomes were evaluated using linear mixed effects models, adjusting for potential confounders.

RESULTS

CHIV had 73% greater HOMA-IR than CHU in ages 6-8 years (95% CI 15.9-158.2%, P < 0.001), and 24.7% greater HOMA-IR than CHU in ages 9-10 years (0.3-55.1%, P = 0.04). By 10-11 years, the difference was not significant (P = 0.161). Longitudinally, triglyceride-to-HDL was 47.94% (34.50-62.73%, P < 0.001) higher in CHIV vs. CHU; LDL was 0.25 mmol/l (0.10-0.39, P = 0.001) higher in CHIV vs. CHU; android fat mass was 11.57% (-21.11 to -0.87%, P = 0.035) lower in CHIV than CHU. No significant difference in SBP was found. CHEU and CHU had similar outcomes.

CONCLUSION

Early-treated CHIV have elevated insulin resistance, which resolves with time. Triglyceride-to-HDL ratio and LDL cholesterol were elevated into puberty. CHIV should be monitored for insulin resistance, dyslipidaemia and subclinical cardiovascular disease.

HIV and SARS-CoV-2 infection in postpartum Kenyan women and their infants

BACKGROUND

HIV may increase SARS-CoV-2 infection risk and COVID-19 severity generally, but data are limited about its impact on postpartum women and their infants. As such, we characterized SARS-CoV-2 infection among mother-infant pairs in Nairobi, Kenya.

METHODS

We conducted a nested study of 62 HIV-uninfected and 64 healthy women living with HIV, as well as their HIV-exposed uninfected (N = 61) and HIV-unexposed (N = 64) infants, participating in a prospective cohort. SARS-CoV-2 serology was performed on plasma collected between May 1, 2020-February 1, 2022 to determine the incidence, risk factors, and symptoms of infection. SARS-CoV-2 RNA PCR and sequencing was also performed on available stool samples from seropositive participants.

RESULTS

SARS-CoV-2 seropositivity was found in 66% of the 126 mothers and in 44% of the 125 infants. There was no significant association between SARS-CoV-2 infection and maternal HIV (Hazard Ratio [HR] = 0.810, 95% CI: 0.517-1.27) or infant HIV exposure (HR = 1.47, 95% CI: 0.859-2.53). Maternal SARS-CoV-2 was associated with a two-fold increased risk of infant infection (HR = 2.31, 95% CI: 1.08-4.94). Few participants (13% mothers, 33% infants) had symptoms; no participant experienced severe COVID-19 or death. Seroreversion occurred in about half of mothers and infants. SARS-CoV-2 sequences obtained from stool were related to contemporaneously circulating variants.

CONCLUSIONS

These data indicate that postpartum Kenyan women and their infants were at high risk for SARS-CoV-2 infection and that antibody responses waned over an average of 8-10 months. However, most cases were asymptomatic and healthy women living with HIV did not have a substantially increased risk of infection or severe COVID-19.

Survival and health of children who are HIV-exposed uninfected: study protocol for the CHERISH (Children HIV-Exposed Uninfected - Research to Inform Survival and Health) dynamic, prospective, maternal-child cohort study

INTRODUCTION

CHERISH is designed to establish a long-term sustainable system for measurement of in utero and postnatal exposures and outcomes in children who are HIV-exposed uninfected (HEU) and HIV-unexposed to compare survival, hospitalisation, growth and neurodevelopment in the Western Cape, South Africa.

METHODS AND ANALYSIS

During 2022-2025, the CHERISH dynamic cohort is prospectively enrolling pregnant people with and without HIV at 24-36 weeks gestation from one urban and one rural community, following mother-child pairs, including children who are HEU (target N=1200) and HIV-unexposed (target N=600) for 3 years from the child's birth. In-person visits occur at enrolment, delivery, 12 months, 24 months and 36 months with intervening 3-monthly telephone data collection. Children and mothers without HIV are tested for HIV at all in-person visits. Data on exposures and outcomes are collected from routine standardised healthcare documentation, maternal interview, measurement (growth and neurodevelopment) at in-person visits and linkage to the Western Cape Provincial Health Data Centre (survival and hospitalisation). A priori adverse birth outcomes, advanced maternal HIV and maternal mental health are considered potential mediators of outcome disparities in children who are HEU and will be evaluated as such in multivariable models appropriate for each outcome.

ETHICS AND DISSEMINATION

Mothers interested in joining the study are taken through a visual informed consent document for their and their child's participation, with the option to consent to anonymised de-identified data being contributed to a public data repository. All data is captured directly into an electronic database using alphanumeric identifiers devoid of identifying information. The cohort study is approved by Human Research Ethics Committees of Stellenbosch University (N20/08/084), University of Cape Town (723/2021) and Western Cape Government (WC_2021_09_007). Findings will be shared with participants, participating communities, local and provincial stakeholders, child health clinicians, researchers and policymakers at local, national and international forums and submitted for publication in peer-reviewed journals.

Vaccination coverage and immunization safety among children with special health status in Chongqing, China

Vaccination of children with special health status has become one of the most urgent issues in China. We aim to evaluate vaccination coverage and safety as well as its associated factors among children with special health status in China during 2016‒2020. We conducted a retrospective cohort review of all children with special health status recorded in the Electronic Immunization Registries System in Chongqing, China, between 2016 and 2020. Univariate and multivariate logistic regression analyses were used to analyze the influence factors. Among the 2,175 children with special health status enrolled in the study, the overall vaccination coverage rate was lower than that among the general population, and the incidence of adverse event in them following immunization was very rare. Children with congenital heart disease were better vaccinated (aOR = 1.508-6.331), while most of the jaundice children had missed vaccination (aOR = 0.441‒0.556). The purchase of vaccine compensation insurance was associated with higher completion rate of basic immunization for Bacillus Calmette-G vaccine (aOR = 1.706, 95% CI: 1.249‒2.329) and rotavirus vaccine (aOR = 1.346, 95% CI: 1.061‒1.708). Children with special health status can be safely vaccinated. However, the vaccination coverage in these huge and vulnerable group is too low to protect them from vaccine-preventable diseases through immunization. More researches and interventions should be conducted to ensure a higher vaccination rate among the children with special health status.

Mitigating Infectious morbidity and Growth deficits in HIV-exposed uninfected infanTs with human Milk Oligosaccharide (MIGH-T MO): a randomised trial protocol

INTRODUCTION

Children who are HIV-exposed uninfected (HEU), that is, children who do not acquire HIV infection despite being born to mothers with HIV, have a higher risk of mortality, infectious morbidity and growth deficits than children who are HIV-unexposed uninfected (HUU). Prior research has focused on breast feeding and has pointed to changes in human milk oligosaccharides (HMOs) associated with maternal HIV that may influence the infant microbiome and thereby lead to these adverse outcomes. However, to our knowledge, no study has attempted to intervene along this pathway to reduce the occurrence of the adverse outcomes in children HEU. We will conduct a double-blind, randomised trial of a synbiotic intervention, which combines an HMO and probiotic, in breastfed infants HEU in South Africa to evaluate whether this intervention has promise to reduce excess infectious morbidity and growth faltering compared with controls.

METHODS AND ANALYSIS

One hundred and forty-four breastfed infants HEU, aged 4 weeks, will be 1:1 randomised to receive either a daily synbiotic or an identical-looking placebo through age 24 weeks. Infants will be followed until age 48 weeks and outcomes of infectious morbidity, growth and biological measurements (eg, microbiota, inflammation and metabolome) will be assessed. Analyses will follow intention-to-treat principles comparing the cohorts as randomised. Infants HEU will be compared across arms with respect to the occurrence of infectious morbidity and growth outcomes through 4-24 weeks and 4-48 weeks using appropriate parametric and non-parametric statistical tests. Additionally, an observational cohort of 40 breastfed infants HUU will be recruited as a comparator group with no intervention.

ETHICS AND DISSEMINATION

Ethical approval for this study has been obtained from the ethics committees at Columbia University and Stellenbosch University. The findings will be disseminated in publications.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier: NCT05282485. SANCTR ID number: DOH-27-122021-6543.

Gut-dependent inflammation and alterations of the intestinal microbiota in individuals with perinatal HIV exposure and different HIV serostatus

OBJECTIVE

HIV-exposed infected (HEI) and uninfected (HEU) children represent the two possible outcomes of maternal HIV infection. Modifications of the intestinal microbiome have been linked to clinical vulnerability in both settings, yet whether HEI and HEU differ in terms of gut impairment and peripheral inflammation/activation is unknown.

DESIGN

We performed a cross-sectional, pilot study on fecal and plasma microbiome as well as plasma markers of gut damage, microbial translocation, inflammation and immune activation in HIV-infected and uninfected children born from an HIV-infected mother.

METHODS

Fecal and plasma microbiome were determined by means of 16S rDNA amplification with subsequent qPCR quantification. Plasma markers were quantified via ELISA.

RESULTS

Forty-seven HEI and 33 HEU children were consecutively enrolled. The two groups displayed differences in fecal beta-diversity and relative abundance, yet similar microbiome profiles in plasma as well as comparable gut damage and microbial translocation. In contrast, monocyte activation (sCD14) and systemic inflammation (IL-6) were significantly higher in HEI than HEU.

CONCLUSION

In the setting of perinatal HIV infection, enduring immune activation and inflammation do not appear to be linked to alterations within the gut. Given that markers of activation and inflammation are independent predictors of HIV disease progression, future studies are needed to understand the underlying mechanisms of such processes and elaborate adjuvant therapies to reduce the clinical risk in individuals with perinatal HIV infection.

Risk factors for stunting in children who are HIV-exposed and uninfected after Option B+ implementation in Malawi

Evidence suggests children HIV-exposed and uninfected (CHEU) experience poor growth. We analysed child anthropometrics and explored factors associated with stunting among Malawian CHEU. Mothers with HIV and their infants HIV-exposed were enroled in a nationally representative prospective cohort within the National Evaluation of Malawi's Prevention of Mother-to-Child HIV Transmission Programme after Option B+ implementation (2014-2018). Anthropometry was measured at enrolment (age 1-6 months), visit 1 (approximately 12 months), and visit 2 (approximately 24 months). Weight-for-age (WAZ) and length-for-age (LAZ) z-scores were calculated using World Health Organization Growth Standards; underweight and stunting were defined as WAZ and LAZ more than 2 standard deviations below the reference median. Multivariable logistic regression restricted to CHEU aged 24 months (±3 months) was used to identify factors associated with stunting. Among 1211 CHEU, 562/1211 attended visit 2, of which 529 were aged 24 months (±3 months) and were included. At age 24 months, 40.4% of CHEU were stunted and/or underweight, respectively. In multi-variable analysis, adjusting for child age and sex, the odds of stunting were higher among CHEU with infectious disease diagnosis compared to those with no diagnosis (adjusted odds ratio = 3.35 [95% confidence interval: 1.82-6.17]), which was modified by co-trimoxazole prophylaxis (p = 0.028). Infant low birthweight was associated with an increased odds of stunting; optimal feeding and maternal employment were correlated with reduced odds. This is one of the first studies examining CHEU growth since Option B+. Interventions to improve linear growth among CHEU should address their multi-faceted health risks, alongside maternal ART prescription, and follow-up of mother-child pairs.

Dynamics of the infant gut microbiota in the first 18 months of life: the impact of maternal HIV infection and breastfeeding

BACKGROUND

Access to antiretroviral therapy (ART) during pregnancy and breastfeeding for mothers with HIV has resulted in fewer children acquiring HIV peri- and postnatally, resulting in an increase in the number of children who are exposed to the virus but are not infected (HEU). HEU infants have an increased likelihood of childhood infections and adverse growth outcomes, as well as increased mortality compared to their HIV-unexposed (HUU) peers. We explored potential differences in the gut microbiota in a cohort of 272 Nigerian infants born to HIV-positive and negative mothers in this study during the first 18 months of life.

RESULTS

The taxonomic composition of the maternal vaginal and gut microbiota showed no significant differences based on HIV status, and the composition of the infant gut microbiota at birth was similar between HUU and HEU. Longitudinal taxonomic composition of the infant gut microbiota and weight-for-age z-scores (WAZ) differed depending on access to breast milk. HEU infants displayed overall lower WAZ than HUU infants at all time points. We observed a significantly lower relative abundance of Bifidobacterium in HEU infants at 6 months postpartum. Breast milk composition also differed by time point and HIV infection status. The antiretroviral therapy drugs, lamivudine and nevirapine, as well as kynurenine, were significantly more abundant in the breast milk of mothers with HIV. Levels of tiglyl carnitine (C5) were significantly lower in the breast milk of mothers without HIV. ART drugs in the breast milk of mothers with HIV were associated with a lower relative abundance of Bifidobacterium longum.

CONCLUSIONS

Maternal HIV infection was associated with adverse growth outcomes of HEU infants in this study, and these differences persist from birth through at least 18 months, which is a critical window for the development of the immune and central nervous systems. We observed that the relative abundance of Bifidobacterium spp. was significantly lower in the gut microbiota of all HEU infants over the first 6 months postpartum, even if HEU infants were receiving breast milk. Breastfeeding was of benefit in our HEU infant cohort in the first weeks postpartum; however, ART drug metabolites in breast milk were associated with a lower abundance of Bifidobacterium. Video abstract.

Predicting neurodevelopmental risk in children born to mothers living with HIV in Kenya: protocol for a prospective cohort study (Tabiri Study)

INTRODUCTION

For the growing number of children with in utero and postpartum exposure to HIV and/or antiretrovirals, it is unclear which exposures or risk factors play a significant role in predicting worse neurodevelopmental outcomes. This protocol describes a prospective longitudinal cohort study of infants born to mothers living with HIV and those born to mothers without HIV. We will determine which risk factors are most predictive of child neurodevelopment at 24 months. We aim to create a risk assessment tool to help predict which children are at risk for worse neurodevelopment outcomes.

METHODS AND ANALYSIS

This study leverages an existing Kenyan cohort to prospectively enrol 500 children born to mothers living with HIV and 500 to those without HIV (n=1000 total) and follow them from birth to age 24 months. The following factors will be measured every 6 months: infectious morbidity and biological/sociodemographic/psychosocial risk factors. We will compare these factors between the two groups. We will then measure and compare neurodevelopment within children in both groups at 24 months of age using the Child Behaviour Checklist and the Bayley Scales of Infant and Toddler Development, third edition. Finally, we will use generalised linear mixed modelling to quantify associations with neurodevelopment and create a risk assessment tool for children ≤24 months.

ETHICS AND DISSEMINATION

The study is approved by the Moi University's Institutional Research and Ethics Committee (IREC/2021/55; Approval #0003892), Kenya's National Commission for Science, Technology and Innovation (NACOSTI, Reference #700244) and Indiana University's Institutional Review Board (IRB Protocol #110990). This study carries minimal risk to the children and their mothers, and all mothers will provide written consent for participation in the study. Results will be disseminated to maternal child health clinics within Uasin Gishu County, Kenya and via papers submitted to peer-reviewed journals and presentation at international conferences.

Clinical pneumonia in the hospitalised child in Malawi in the post-pneumococcal conjugate vaccine era: a prospective hospital-based observational study

OBJECTIVE

Assess characteristics of clinical pneumonia after introduction of pneumococcal conjugate vaccine (PCV), by HIV exposure status, in children hospitalised in a governmental hospital in Malawi.

METHODS AND FINDINGS

We evaluated 1139 children ≤5 years old hospitalised with clinical pneumonia: 101 HIV-exposed, uninfected (HEU) and 1038 HIV-unexposed, uninfected (HUU). Median age was 11 months (IQR 6-20), 59% were male, median mid-upper arm circumference (MUAC) was 14 cm (IQR 13-15) and mean weight-for-height z score was -0.7 (±2.5). The highest Respiratory Index of Severity in Children (RISC) scores were allocated to 10.4% of the overall cohort. Only 45.7% had fever, and 37.2% had at least one danger sign at presentation. The most common clinical features were crackles (54.7%), nasal flaring (53.5%) and lower chest wall indrawing (53.2%). Compared with HUU, HEU children were significantly younger (9 months vs 11 months), with lower mean birth weight (2.8 kg vs 3.0 kg) and MUAC (13.6 cm vs 14.0 cm), had higher prevalence of vomiting (32.7% vs 22.0%), tachypnoea (68.4% vs 49.8%) and highest RISC scores (20.0% vs 9.4%). Five children died (0.4%). However, clinical outcomes were similar for both groups.

CONCLUSIONS

In this post-PCV setting where prevalence of HIV and malnutrition is high, children hospitalised fulfilling the WHO Integrated Management of Childhood Illness criteria for clinical pneumonia present with heterogeneous features. These vary by HIV exposure status but this does not influence either the frequency of danger signs or mortality. The poor performance of available severity scores in this population and the absence of more specific diagnostics hinder appropriate antimicrobial stewardship and the rational application of other interventions.

Higher Hospitalization Rates in Children Born HIV-exposed Uninfected in British Columbia, Canada, Between 1990 and 2012

BACKGROUND

Compared with children who are HIV-unexposed and uninfected (CHUU), children who are HIV-exposed and uninfected (CHEU) experience more clinical complications. We investigated hospitalizations among CHEU by antenatal antiretroviral therapy (ART) exposure, in British Columbia, Canada.

METHODS

This retrospective controlled cohort study used administrative health data from 1990 to 2012. CHEU and CHUU were matched 1:3 for age, sex and maternal geographical area of residence. We determined adjusted odds ratios (aORs) via conditional logistic regression, adjusting for maternal risk factors.

RESULTS

A total of 446 CHEU and 1333 CHUU were included. Compared with CHUU, more CHEU experienced one or more lifetime hospitalization (47.3% vs. 29.8%), one or more neonatal hospitalization (40.4% vs. 27.6%), and any intensive care unit admission (28.5% vs. 9.2%). In adjusted analyses, CHEU experienced higher odds of any lifetime hospitalization (aOR 2.30, 95% confidence interval 1.81-2.91) and neonatal hospitalization (aOR 2.14, 95% confidence interval 1.68-2.73), compared with CHUU. There was, however, no difference in infection-related hospitalizations (9.0% vs. 7.5%), which were primarily respiratory tract infections among both CHEU and CHUU. CHEU whose mothers-initiated ART preconception showed lower odds of infection-related hospitalizations than children whose mothers initiated ART during pregnancy or received no ART.

CONCLUSIONS

CHEU experienced increased odds of hospitalization relative to CHUU. A substantial number of CHEU hospitalizations occurred within the neonatal period and were ICU admissions. Initiating ART preconception may reduce the risk of infection-related hospitalizations. These findings reinforce the benefit of ART in pregnancy and the need for ongoing pediatric care to reduce hospitalizations.

Stereotypic Expansion of T Regulatory and Th17 Cells during Infancy Is Disrupted by HIV Exposure and Gut Epithelial Damage

Few studies have investigated immune cell ontogeny throughout the neonatal and early pediatric period, when there is often increased vulnerability to infections. In this study, we evaluated the dynamics of two critical T cell populations, T regulatory (Treg) cells and Th17 cells, over the first 36 wk of human life. First, we observed distinct CD4⁺ T cells phenotypes between cord blood and peripheral blood, collected within 12 h of birth, showing that cord blood is not a surrogate for newborn blood. Second, both Treg and Th17 cells expanded in a synchronous fashion over 36 wk of life. However, comparing infants exposed to HIV in utero, but remaining uninfected, with HIV-unexposed uninfected control infants, there was a lower frequency of peripheral blood Treg cells at birth, resulting in a delayed expansion, and then declining again at 36 wk. Focusing on birth events, we found that Treg cells coexpressing CCR4 and α4β7 inversely correlated with plasma concentrations of CCL17 (the ligand for CCR4) and intestinal fatty acid binding protein, IL-7, and CCL20. This was in contrast with Th17 cells, which showed a positive association with these plasma analytes. Thus, despite the stereotypic expansion of both cell subsets over the first few months of life, there was a disruption in the balance of Th17 to Treg cells at birth likely being a result of gut damage and homing of newborn Treg cells from the blood circulation to the gut.

Childhood lung function following perinatal HIV infection and early antiretroviral therapy initiation: a cross-sectional study

Despite the introduction of antiretroviral therapy (ART), HIV-associated pulmonary complications remain prevalent in children following perinatal HIV infection. In the post-ART era the incidence of opportunistic infections has decreased; however, non-infectious complications including diminished lung function are common. It is unclear whether early initiation of ART influences lung function later in life. We performed a cross-sectional study examining pulmonary function tests (PFT) (spirometry, plethysmography, carbon monoxide diffusing capacity) in HIV-unexposed (HU), HIV-exposed-uninfected (HEU) and perinatally HIV-infected children on early ART (HIV+) recruited from the Cape Town arms of the CHER and IMPAACT 1060 trials. PFT was performed once children could participate (October 2013 to January 2020). Global Lung Initiative reference software was used for Z-standardisation of lung function by sex, age and height. In total 394 children (HU n=90, HEU n=162, HIV+ n=142) underwent PFT, median age 8.7 (IQR 7.7-9.8) years. HIV+ had ART initiated at a median age of 17.6 (8.0-36.7) weeks. Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC Z-scores were similar in all groups. Plethysmography demonstrated air-trapping with increased total lung capacity (TLC), functional residual capacity, residual volume (RV) and RV/TLC Z-scores in HIV+. There were no differences in alveolar volume; however, diffusing capacity was increased in HIV+. Our findings indicate that following perinatal HIV infection, early ART may attenuate HIV-associated lung disease and is associated with normal childhood spirometry. However plethysmography demonstrates that small airway dysfunction is more pronounced in HIV+. Longitudinal follow-up is required to assess if these children are at risk of obstructive airway disease later in life.

Increased infectious-cause hospitalization among infants who are HIV-exposed uninfected compared with HIV-unexposed

OBJECTIVES

Increased risk of morbidity and hospitalization has been observed in children who are HIV-exposed uninfected (HEU) compared with HIV-unexposed uninfected (HUU). Studies in the era of universal maternal antiretroviral treatment (ART) are limited.

DESIGN

Prospective cohort.

METHODS

We investigated hospitalization between 29 days and 12 months of life in a South African cohort of infants born between February 2017 and January 2019 (HEU = 455; HUU = 458). All mothers known with HIV during pregnancy received ART. We reviewed hospital records and classified and graded infectious diagnoses using a standardized tool. We examined factors associated with infectious-cause hospitalization using mixed-effects Poisson regression.

RESULTS

Infants HEU vs. HUU had higher all-cause and infectious-cause hospitalization (13 vs. 7%, P = 0.004 and 10 vs. 6%, P = 0.014, respectively). Infectious causes accounted for most hospitalizations (77%). More infants HEU were hospitalized with severe or very severe infections than those HUU (9 vs. 6%; P = 0.031). Mortality (<1%) did not differ between groups. HIV exposure was a significant risk factor for infectious-cause hospitalization [adjusted incidence rate ratios (aIRRs) = 2.8; 95% confidence interval (CI) 1.5-5.4]. Although increased incidence of preterm birth (14 vs. 10%; P < 0.05) and shorter duration of breastfeeding (44 vs. 68% breastfed for ≥3 months, P < 0.001) among infants HEU vs. HUU contributed to increased hospitalization, they did not account for all the increased risk.

CONCLUSION

Infectious-cause hospitalization incidence was higher among infants HEU vs. HUU, likely partly because of higher incidence of preterm birth and lower breastfeeding rates among infants HEU. The increased infectious disease burden in HEU infants has important implications for health services in sub-Saharan Africa.

Protection of Vaccine Preventable Diseases in a Population of HIV-Infected Children: A 3 Years Prospective Study

Human Immunodeficiency Virus (HIV) infected children have a 30-70% chance of being incompletely immunized and may not respond serologically with the same magnitude or durability as uninfected children. The aim of the study was to describe the rate of protective antibodies titre and the persistence of the response against four recommended vaccinations in HIV infected children and adolescents. A two-phase observational study was performed in which protective IgG antibodies to measles, mumps, rubella and hepatitis B were determined and monitored for 12 and 24 months, in 26 perinatally HIV-infected children. The rate of protection for rubella and hepatitis B was significantly lower in the HIV group compared to the control group (92% vs. 65% for rubella and 78.4% vs. 45.4% for hepatitis B; p < 0.05). Children who received primary vaccination after initiating combination antiretroviral therapy (cART) had a higher rate of response. Seronegative patients who received a booster dose of vaccine had a good immunological response. HIV infection is associated with a lower response to vaccines against rubella and hepatitis. The beginning of cART before vaccination may be associated with a better response. The evaluation of the serological response is crucial in children with HIV infection in order to evaluate the protection of vaccine preventable diseases.

Impact of HIV status on systemic inflammation during pregnancy

OBJECTIVE

There are limited studies on the association of HIV infection with systemic inflammation during pregnancy.

DESIGN

A cohort study (N = 220) of pregnant women with HIV (N = 70) (all on antiretroviral therapy) and without HIV (N = 150) were enrolled from an antenatal clinic in Pune, India.

METHODS

The following systemic inflammatory markers were measured in plasma samples using immunoassays: soluble CD163 (sCD163), soluble CD14 (sCD14), intestinal fatty acid-binding protein (I-FABP), C-reactive protein (CRP), alpha 1-acid glycoprotein (AGP), interferon-β (IFNβ), interferon-γ (IFNγ), interleukin (IL)-1β, IL-6, IL-13, IL-17A, and tumor necrosis factor α (TNFα). Generalized estimating equation (GEE) and linear regression models were used to assess the association of HIV status with each inflammatory marker during pregnancy and by trimester, respectively.

RESULTS

Pregnant women with HIV had higher levels of markers for gut barrier dysfunction (I-FABP), monocyte activation (sCD14) and markers of systemic inflammation (IL-6 and TNFα), but surprisingly lower levels of AGP, an acute phase protein, compared with pregnant women without HIV, with some trimester-specific differences.

CONCLUSION

Our data show that women with HIV had higher levels of markers of gut barrier dysfunction, monocyte activation and systemic inflammation. These markers, some of which are associated with preterm birth, might help explain the increase in adverse birth outcomes in women with HIV and could suggest targets for potential interventions.

Neurological development of children who are HIV-exposed and uninfected

Widespread use of antiretroviral drugs for pregnant/breastfeeding females with human immunodeficiency virus (HIV) has led to declining vertical transmission. Despite being HIV-uninfected, the increasing number of children who are HIV-exposed and uninfected (CHEU) often present with developmental alterations. We review seminal and recent evidence on the neurological development of CHEU and associations with early life HIV/antiretroviral exposure. Our conceptual model highlights the numerous exposures and universal risk factors for CHEU developmental disorders. Early studies suggest a significant association between HIV exposure and neurological abnormalities, varying according to the burden of HIV-specific exposures and other risk factors. More recent observations from the modern era are inconsistent, although some studies suggest specific antiretrovirals may adversely affect neurological development of CHEU. As the CHEU population continues to grow, alongside simultaneous increases in types and combinations of antiretrovirals used in pregnancy, long-term monitoring of CHEU is necessary for understanding the effects of HIV/antiretroviral exposure on CHEU developmental outcomes. What this paper adds Evidence on the neurological development of children who are human immunodeficiency virus (HIV)-exposed and uninfected (CHEU) is synthesized. Comparisons are made to children who are HIV-unexposed, across treatment eras and settings, and by antiretroviral drug regimens and drug classes. CHEU exposures are complex and include HIV-specific and universal risk factors which may affect development during the early years of life.

Longitudinal Follow-Up of Blood Telomere Length in HIV-Exposed Uninfected Children Having Received One Year of Lopinavir/Ritonavir or Lamivudine as Prophylaxis

Telomere shortening can be enhanced upon human immunodeficiency virus (HIV) infection and by antiretroviral (ARV) exposures. The aim of this study was to evaluate the acute and long-term effect on telomere shortening of two ARV prophylaxes, lopinavir/ritonavir (LPV/r) and lamivudine (3TC), administered to children who are HIV-exposed uninfected (CHEU) to prevent HIV acquisition through breastfeeding during the first year of life, and to investigate the relationship between telomere shortening and health outcomes at six years of age. We included 198 CHEU and measured telomere length at seven days of life, at week-50 and at six years (year-6) using quantitative polymerase chain reaction. At week-50, telomere shortening was observed among 44.3% of CHEU, irrespective of the prophylactic treatment. Furthermore, this telomere shortening was neither associated with poor growth indicators nor neuropsychological outcomes at year-6, except for motor abilities (MABC test n = 127, β = -3.61, 95%CI: -7.08, -0.14; p = 0.04). Safety data on telomere shortening for infant HIV prophylaxis are scarce. Its association with reduced motor abilities deserves further attention among CHEU but also HIV-infected children receiving ARV treatment.

Levels of vaccination coverage among HIV-exposed children in China: a retrospective study

Background

Vaccination is crucial for human immunodeficiency virus (HIV)-exposed children because of their increased risk of morbidity and mortality from various vaccine-preventable diseases. However, studies have shown that they are at high risk of incomplete vaccination. Although China has developed prevention of mother-to-child transmission (PMTCT) of HIV programs substantially over the past decades, few studies have investigated the immunization levels of Chinese HIV-exposed children. Therefore, we aimed to evaluate vaccination coverage and its associated factors among HIV-exposed children in China during 2016‒2018.

Methods

We conducted a retrospective cohort review of all cases of Chinese HIV-exposed children born between July 1, 2016 and June 30, 2018 recorded in the Chinese information system on PMTCT. The vaccination coverage indicators refer to the percentage of children who received recommended basic vaccines, including Bacillus Calmette-Guérin (BCG), hepatitis B (HepB), polio, measles-containing vaccine (MCV), and diphtheria-tetanus-pertussis-containing (DTP) vaccine. Univariate and multivariate logistic regression analyses expressed as crude odds ratios (cORs) and adjusted odds ratios (aORs), each with 95% confidence intervals (95% CI), were performed to compare the proportional differences of factors associated with vaccine coverage.

Results

Among the enrolled 10 033 children, the vaccination rate was 54.1% for BCG, 84.5% for complete HepB vaccination, 54.5% for complete polio vaccination, 51.3% for MCV, and 59.5% for complete DTP vaccination. Children with perinatally acquired HIV (PHIV) were 2.46‒3.82 times less likely to be vaccinated than HIV-exposed uninfected children. Multivariate logistic regression indicated that children of Han ethnicity (aOR = 1.33‒2.04), children with early infant diagnosis (EID) of HIV (aOR = 1.86‒3.17), and children whose mothers had better education (college or above, aOR = 1.63‒2.51) had higher odds of being vaccinated. Most of the deceased children (aOR = 4.28‒21.55) missed vaccination, and PHIV (aOR = 2.46‒3.82) significantly affected immunization.

Conclusions

Chinese HIV-exposed children had low vaccination coverage, which is a serious health challenge that needs to be addressed thoroughly. Interventions should be developed with a focus on minority HIV-exposed children whose mothers do not have formal education. Particularly, more attention should be paid to EID to increase access to immunization.

Graphical abstract

Infants 21-90 days presenting with a possible serious bacterial infection - are evaluation algorithms from high income countries applicable in the South African public health sector?

BACKGROUND

Young infants with a possible serious bacterial infection (SBI) are a very common presentation to emergency centres (ECs). It is often difficult to distinguish clinically between self-limiting viral infections and an SBI. Available evaluation algorithms to assist clinicians are mostly from high-income countries. Data to inform clinical practice in low- and middle-income countries are lacking.

OBJECTIVES

To determine the period prevalence of SBI and invasive bacterial infection (IBI) and describe current practice in the assessment and management of young infants aged 21-90 days presenting with a possible SBI to a Paediatric Emergency centre (PEC) in Cape Town, South Africa.

METHODS

A retrospective cross-sectional review of infants 21-90 days old presenting to the Tygerberg Hospital PED between 1 January 2016 and 31 May 2016.

RESULTS

A total of 248 infants 21-90 days were included in the study. Sixty-two patients (25%, 95% CI 20-30) had an SBI and 13 (5.2%, 95% CI 3-8) had an IBI. One hundred and sixty-five infants had a possible SBI based on WHO IMCI criteria. The sensitivity of the WHO IMCI criteria in detecting SBI was 82.3% (95% CI 70.5-90.8) and the specificity 38.7% (95% CI 31.7-46.1). More than half (51.2%) of the infants received antibiotics within the 48 h prior to presentation, of which 33.5% included intramuscular injection of Ceftriaxone. Only 20 (8.0%) patients in this age group were discharged home after initial evaluation. A significant relationship was noted between fever and the risk of SBI (p-value 0.010) and IBI (p-value 0.009). There also appeared to be a significant relationship between nutritional status and IBI (p-value 0.013).

CONCLUSION

Period prevalence of SBI and IBI was higher compared to that published in the literature. Validated evaluation algorithms to stratify risk of SBI are needed to assist clinicians in diagnosing and managing infants appropriately in low- and middle-income settings.

Respiratory Complications in Children and Adolescents with Human Immunodeficiency Virus

Respiratory complications comprise a large proportion of the burden of mortality and morbidity in children with human immunodeficiency virus (HIV). HIV-associated lower respiratory tract infection (LRTI) has declined in incidence with early diagnosis and use of antiretroviral therapy (ART) but is widespread in areas with limited access to ART. HIV-exposed uninfected infants have a higher risk of LRTI early in life than unexposed infants. Pulmonary tuberculosis (PTB) presenting as acute or chronic disease is common in highly TB endemic areas. Chronic lung disease is common; preceding LRTI, PTB or late initiation of ART are risk factors.

Flexible modelling of risk factors on the incidence of pneumonia in young children in South Africa using piece-wise exponential additive mixed modelling

Introduction

Recurrent episodes of pneumonia are frequently modeled using extensions of the Cox proportional hazards model with the underlying assumption of time-constant relative risks measured by the hazard ratio. We aim to relax this assumption in a study on the effect of factors on the evolution of pneumonia incidence over time based on data from a South African birth cohort study, the Drakenstein child health study.

Methods

We describe and apply two models: a time-constant and a time-varying relative effects model in a piece-wise exponential additive mixed model’s framework for recurrent events. A more complex model that fits in the same framework is applied to study the continuously measured seasonal effects.

Results

We find that several risk factors (male sex, preterm birth, low birthweight, lower socioeconomic status, lower maternal education and maternal cigarette smoking) have strong relative effects that are persistent across time. When time-varying effects are allowed in the model, HIV exposure status (HIV exposed & uninfected versus HIV unexposed) shows a strong relative effect for younger children, but this effect weakens as children grow older, with a null effect reached from about 15 months. Weight-for-length at birth shows a time increasing relative effect. We also find that children born in the summer have a much higher risk of pneumonia in the 3-to-8-month age period compared with children born in winter.

Conclusion

This work highlights the usefulness of flexible modelling tools in recurrent events models. It avoids stringent assumptions and allows estimation and visualization of absolute and relative risks over time of key factors associated with incidence of pneumonia in young children, providing new perspectives on the role of risk factors such HIV exposure.

Supplementary Information

The online version contains supplementary material available at (10.1186/s12874-020-01194-6).

Differential effects of antiretroviral drug toxicity in male versus female children who are HIV-exposed but uninfected

: In recent years, widespread use of antiretroviral therapy (ART) during pregnancy has been increasingly effective in reducing risk of vertical transmission of HIV, with over 80% of pregnant women living with HIV now accessing ART, and a 41% reduction in new infections in children between 2010 and 2018. Despite these strides, the developmental toxicity of widely administered antiretroviral drugs (ARVs) remains poorly described and existing literature often fails to account for fetal and infant sex as a variable. Recent reports have identified associations between in-utero exposure to commonly used antiretroviral regimens and alteration in neurodevelopment, growth, and metabolism amongst children who are HIV-exposed but uninfected, with findings of sex differences in the prevalence and severity of ARV toxicity. These differences are potentially explained by variable exposure to ARV drugs in utero or exacerbation of existing sex-linked risk factors. Fetal ARV exposure is mediated by placental and fetal drug transporters and metabolic enzymes, which may contribute to the manifestation of sex differences. Existing evidence of sex differences in ARV toxicity in fetal development is concerning, and demands further research to guide optimal treatment options for maternal health and prevention of vertical HIV transmission.

Cotrimoxazole Prophylaxis Increases Resistance Gene Prevalence and α-Diversity but Decreases β-Diversity in the Gut Microbiome of Human Immunodeficiency Virus-Exposed, Uninfected Infants

BACKGROUND

Prophylactic cotrimoxazole treatment is recommended in human immunodeficiency virus (HIV)-exposed, uninfected (HEU) infants, but the effects of this treatment on developing HEU infant gut microbiotas and resistomes are largely undefined.

METHODS

We analyzed whole-metagenome sequencing data from 163 longitudinally collected stool samples from 63 HEU infants randomized to receive (n = 34; CTX-T) or to not receive (n = 29; CTX-N) prophylactic cotrimoxazole treatment. We generated taxonomic, functional pathway, and resistance gene profiles for each sample and compared microbiome signatures between the CTX-T and CTX-N infants.

RESULTS

Metagenomic analysis did not reveal significant differences in taxonomic or functional pathway α-diversity between CTX-T and CTX-N infants. In contrast, resistance gene prevalence (P = .00719) and α-diversity (P = .0045) increased in CTX-T infants. These differences increased over time for both resistance gene prevalence measured by log-normalized abundance (4-month mean, 0.71 [95% confidence interval {CI}, .2-1.2] and 6-month mean, 0.85 [95% CI, .1-1.7]) and α-diversity (P = .0045). Unlike α-diversity, interindividual gut microbiome taxonomic (mean, -0.11 [95% CI, -.15 to -.077]), functional taxonomic (mean, -0.050 [95% CI, -.084 to -.017]), and resistance gene (mean, -0.13 [95% CI, -.17 to -.099]) β-diversity decreased in CTX-T infants compared with CTX-N infants. These results are consistent with persistent antibiotic selection pressure.

CONCLUSIONS

Cotrimoxazole prophylaxis in HEU infants decreased gut microbiome β-diversity and increased antibiotic resistance gene α-diversity and prevalence. Antibiotic resistance is a growing threat, especially in low- and middle-income countries where the higher perinatal HIV exposure rates result in cotrimoxazole prophylaxis. Understanding effects from current HEU infant antibiotic prophylaxis guidelines will inform guideline revisions and efforts to reduce increasing antibiotic resistance.

Reasons for the Early Introduction of Complementary Feeding to HIV-Exposed Infants in the Eastern Cape, South Africa: An Exploratory Qualitative Study

Exclusive breastfeeding has many health benefits for the baby and the mother. This study explored the reasons for the early introduction of supplementary feeding before six months, and the issues faced by parturient women in practicing exclusive breast feeding (EBF) for their HIV-exposed infants in the Eastern Cape, South Africa. Narratives from 319 parturient women with HIV (aged 18 years and above) were collected at three hospitals in the Eastern Cape through semi-structured interviews over a period of five months. Qualitative data were analysed using thematic content analysis. The maternal perception of HIV transmission from breast milk influenced the decision for the immediate introduction of formula feeding. Breast sores, lumps, surgery and perceived insufficiency of milk influenced the decision of mothers to initiate formula feeding within the first two months. However, mothers who initiated complementary feeding after two months were driven by factors common among newborns (refusal of breast milk, baby crying inconsolably and fear of losing weight) and social factors (economic or financial hardships and work-related challenges). Additionally, advice from family members weighed heavily in the decision to switch to complementary feeding, contrary to the healthcare providers' recommendations. Early complementary feeding for HIV-exposed infants is influenced by maternal perceptions of breast milk transmission, breast and infant factors and socio-economic and cultural practices in the region. Thus, behavioural interventions tailored towards promoting exclusive breastfeeding practices in this population, starting from the pre-natal and continuing during the post-partum period, should also target the immediate family members. National policy should focus on creating an EBF-friendly environment at the workplace for women.

In utero exposure to protease inhibitor-based antiretroviral regimens delays growth and developmental milestones in mice

Antiretroviral therapy (ART) in pregnancy has dramatically reduced HIV vertical transmission rates. Consequently, there is a growing number of children that are HIV exposed uninfected (CHEUs). Studies suggest that CHEUs exposed in utero to ART may experience developmental delays compared to their peers. We investigated the effects of in utero ART exposure on perinatal neurodevelopment in mice, through assessment of developmental milestones. Developmental milestone tests (parallel to reflex testing in human infants) are reflective of brain maturity and useful in predicting later behavioral outcomes. We hypothesized that ART in pregnancy alters the in utero environment and thereby alters developmental milestone outcomes in pups. Throughout pregnancy, dams were treated with boosted-atazanavir combined with either abacavir/lamivudine (ATV/r/ABC/3TC), or tenofovir/emtricitabine (ATV/r/TDF/FTC), or water as control. Pups were assessed daily for general somatic growth and on a battery of tests for primitive reflexes including surface-righting, negative-geotaxis, cliff-aversion, rooting, ear-twitch, auditory-reflex, forelimb-grasp, air-righting, behaviors in the neonatal open field, and olfactory test. In utero exposure to either ART regimen delayed somatic growth in offspring and evoked significant delays in the development of negative geotaxis, cliff-aversion, and ear-twitch reflexes. Exposure to ATV/r/ABC/3TC was also associated with olfactory deficits in male and forelimb grasp deficits in female pups. To explore whether delays persisted into adulthood we assessed performance in the open field test. We observed no significant differences between treatment arm for males. In females, ATV/r/TDF/FTC exposure was associated with lower total distance travelled and less ambulatory time in the centre, while ATV/r/ABC/3TC exposure was associated with higher resting times compared to controls. In utero PI-based ART exposure delays the appearance of primitive reflexes that involve vestibular and sensory-motor pathways in a mouse model. Our findings suggest that ART could be disrupting the normal progress/maturation of the underlying neurocircuits and encourage further investigation for underlying mechanisms.

Innate Immune Responses and Gut Microbiomes Distinguish HIV-Exposed from HIV-Unexposed Children in a Population-Specific Manner

In both high- and low-income countries, HIV-negative children born to HIV-positive mothers (HIV exposed, uninfected [HEU]) are more susceptible to severe infection than HIV-unexposed, uninfected (HUU) children, with altered innate immunity hypothesized to be a cause. Both the gut microbiome and systemic innate immunity differ across biogeographically distinct settings, and the two are known to influence each other. And although the gut microbiome is influenced by HIV infection and may contribute to altered immunity, the biogeography of immune-microbiome correlations among HEU children have not been investigated. To address this, we compared the innate response and the stool microbiome of 2-y-old HEU and HUU children from Belgium, Canada, and South Africa to test the hypothesis that region-specific immune alterations directly correlate to differences in their stool microbiomes. We did not detect a universal immune or microbiome signature underlying differences between HEU versus HUU that was applicable to all children. But as hypothesized, population-specific differences in stool microbiomes were readily detected and included reduced abundances of short-chain fatty acid-producing bacteria in Canadian HEU children. Furthermore, we did not identify innate immune-microbiome associations that distinguished HEU from HUU children in any population. These findings suggest that maternal HIV infection is independently associated with differences in both innate immunity and the stool microbiome in a biogeographical population-specific way.

HIV-Exposed, Uninfected Infants in Uganda Experience Poorer Growth and Body Composition Trajectories than HIV-Unexposed Infants

BACKGROUND

HIV-uninfected infants of HIV-positive women may experience worse growth and health outcomes than infants of HIV-negative women, but this has not been thoroughly investigated under the World Health Organization's most recent recommendations to reduce vertical transmission.

OBJECTIVE

To determine whether HIV-exposed and -uninfected (HEU) infants whose mothers received Option B+ have higher odds of experiencing suboptimal growth trajectories than HIV-unexposed, -uninfected infants, and if this relationship is affected by food insecurity.

DESIGN

Repeated anthropometric measures were taken on 238 infants (HEU = 86) at 1 week and 1, 3, 6, 9, and 12 months after delivery in Gulu, Uganda. Latent class growth mixture modeling was used to develop trajectories for length-for-age z-scores, weight-for-length z-scores, mid-upper arm circumference, sum of skinfolds, and arm fat area. Multinomial logistic models were also built to predict odds of trajectory class membership, controlling for socioeconomic factors.

RESULTS

HEU infants had greater odds of being in the shortest 2 length-for-age z-scores trajectory classes [odds ratio (OR) = 3.80 (1.22-11.82), OR = 8.72 (1.80-42.09)] and higher odds of being in smallest sum of skinfolds trajectory class [OR = 3.85 (1.39-10.59)] vs. unexposed infants. Among HEU infants, increasing food insecurity was associated with lower odds of being in the lowest sum of skinfolds class [OR = 0.86 (0.76-0.98)].

CONCLUSIONS

There continues to be differences in growth patterns by HIV-exposure under the new set of World Health Organization guidelines for the prevention of mother-to-child transmission of HIV and the feeding of HEU infants in low-resource settings that are not readily identified through traditional mixed-effects modeling. Food insecurity was not associated with class membership, but differentially affected adiposity by HIV-exposure status.