Increased risk for and mortality from invasive pneumococcal disease in HIV-exposed but uninfected infants aged <1 year in South Africa, 2009-2013

Risk Factors for Severe COVID-19 Among Children and Adolescents Enrolled in Acute Respiratory Infection Sentinel Surveillance in South Africa, 2020-2022

BACKGROUND

Identifying children at risk for severe COVID-19 disease from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may guide future mitigation interventions. Using sentinel surveillance data, we aimed to identify risk factors for SARS-CoV-2-associated hospitalisation among patients aged ≤ 18 years with respiratory illness.

METHODS

From April 2020 to March 2022, patients meeting study case definitions were enrolled at four outpatient influenza-like illness (ILI) and five inpatient severe respiratory infection (SRI) surveillance sites and tested for SARS-CoV-2 infection using polymerase chain reaction (PCR). Each ILI clinic shared a catchment area with its corresponding SRI hospital. Potential risk factors for SARS-CoV-2-associated hospitalisation were analysed using multivariable logistic regression by comparing inpatient versus outpatient SARS-CoV-2 cases.

RESULTS

Of 4688 participants aged ≤ 18 years, 4556 (97%) with complete PCR and HIV data were included in the analysis. Among patients with ILI and SRI, 92/1145 (8%) and 154/3411 (5%) tested SARS-CoV-2 positive, respectively. Compared to outpatients, hospitalised SARS-CoV-2 cases were associated with age < 6 months ([adjusted odds ratio (aOR) 8.0, 95% confidence interval (CI) 2.7-24.0] versus 1-4 years); underlying medical condition other than HIV [aOR 5.8, 95% CI 2.3-14.6]; laboratory-confirmed Omicron BA.1/BA.2 or Delta variant ([aOR 4.9, 95% CI 1.7-14.2] or [aOR 2.8, 95% CI 1.1-7.3] compared to ancestral SARS-CoV-2); and respiratory syncytial virus coinfection [aOR 6.2, 95% CI 1.0-38.5].

CONCLUSION

Aligning with previous research, we identified age < 6 months or having an underlying condition as risk factors for SARS-CoV-2-associated SRI hospitalisation and demonstrated the potential of sentinel surveillance to monitor COVID-19 in children.

Gut Microbiota and Other Factors Associated With Increased Regulatory T Cells in Hiv-exposed Uninfected Infants

HIV-exposed uninfected infants (HEU) have higher infectious morbidity than HIV-unexposed infants (HUU). HEU have multiple immune defects of unknown origin. We hypothesized that HEU have higher regulatory T cells (Treg) than HUU, which may dampen their immune defenses against pathogens. We compared 25 Treg subsets between HEU and HUU and sought the factors that may affect Treg frequencies. At birth, 3 Treg subsets, including CD4 + FOXP3 + and CD4 + FOXP3 + CD25+, had higher frequencies in 123 HEU than 117 HUU and 3 subsets were higher in HUU. At 28 and 62 weeks of life, 5 Treg subsets were higher in HEU, and none were higher in HUU. The frequencies of the discrepant Treg subsets correlated at birth with differential abundances of bacterial taxas in maternal gut microbiome and at subsequent visits in infant gut microbiomes. In vitro, bacterial taxa most abundant in HEU expanded Treg subsets with higher frequencies in HEU, recapitulating the in vivo observations. Other factors that correlated with increased Treg were low maternal CD4 + T cells in HEU at birth and male sex in HUU at 28 weeks. We conclude that maternal and infant gut dysbiosis are central to the Treg increase in HEU and may be targeted by mitigating interventions.

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.

A phase 3 study of safety and immunogenicity of V114, a 15-valent pneumococcal conjugate vaccine, followed by 23-valent pneumococcal polysaccharide vaccine, in children with HIV

OBJECTIVES

To evaluate the safety and immunogenicity of V114 [15-valent pneumococcal conjugate vaccine (PCV) containing serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9 V, 14, 18C, 19A, 19F, 22F, 23F, 33F], followed by 23-valent pneumococcal polysaccharide vaccine (PPSV23) 8 weeks later, in children with HIV.

DESIGN

This phase 3 study (NCT03921424) randomized participants 6-17 years of age with HIV (CD4 + T-cell count ≥200 cells/μl, plasma HIV RNA <50 000 copies/ml) to receive V114 or 13-valent PCV (PCV13) in a double-blind manner on Day 1, followed by PPSV23 at Week 8.

METHODS

Adverse events (AEs), pneumococcal serotype-specific immunoglobulin G (IgG), and opsonophagocytic activity (OPA) were evaluated 30 days after each vaccination.

RESULTS

The proportion of participants experiencing at least one AE post-PCV was 78.8% in the V114 group ( n  = 203) and 69.6% in the PCV13 group ( n  = 204); respective proportions post-PPSV23 were 75.4% ( n  = 203) and 77.2% ( n  = 202). There were no vaccine-related serious AEs. IgG geometric mean concentrations (GMCs) and OPA geometric mean titers (GMTs) were generally comparable between V114 and PCV13 for shared serotypes at Day 30, and were higher for V114 compared with PCV13 for the additional V114 serotypes 22F and 33F. Approximately 30 days after PPSV23, IgG GMCs and OPA GMTs were generally comparable between the V114 and PCV13 groups for all 15 serotypes in V114.

CONCLUSIONS

In children with HIV, a sequential administration of V114 followed 8 weeks later with PPSV23 is well tolerated and induces immune responses for all 15 pneumococcal serotypes included in V114.

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.

A 12-month Prospective Study of HIV-infected and HIV-uninfected Women and Their Infants in Malawi: Comparative Analysis of Clinical Events and Infant Growth

Few studies have compared clinical outcomes in HIV-exposed uninfected (HEU) and HIV-unexposed uninfected (HUU) infants in the current scenario of universal and lifelong maternal antiretroviral therapy (ART). HIV-uninfected and HIV-infected Malawian women receiving ART and their breastfed infants were followed for 12 months postpartum, analyzing the rates of infectious and noninfectious events and assessing infant growth at 6 weeks, 6 months, and 12 months. The cohorts included 227 mothers (70 HIV-negative, 157 HIV-positive) and 235 infants (72 HUU, 163 HEU). No maternal or infant deaths occurred during follow-up. HIV-negative women were less likely to complete follow-up (48.6% versus 91.1%). Mothers with and without HIV had similar rates of both infectious and noninfectious events per person-month. Infants who were HEU, compared with HUU, had higher rates of events of any type, lower respiratory tract infections (LRTI), and noninfectious events. HEU had lower body mass index (BMI) at 6 weeks but did not differ from HUU in all anthropometric measures at 6 and 12 months; in growth between 6 weeks and 12 months; and in occurrence of stunting, underweight, and wasting at 6 weeks, 6 months, and 12 months. During the first year of life, infants who were HEU, compared with HUU, showed a transiently lower BMI and an increased risk of LRTI.

Immune and Metabolic Alterations in Children with Perinatal HIV Exposure

With the global rollout of mother-to-child prevention programs for women living with HIV, vertical transmission has been all but eliminated in many countries. However, the number of children who are exposed in utero to HIV and antiretroviral therapy (ART) is ever-increasing. These children who are HIV-exposed-but-uninfected (CHEU) are now well recognized as having persistent health disparities compared to children who are HIV-unexposed-and-uninfected (CHUU). Differences reported between these two groups include immune dysfunction and higher levels of inflammation, cognitive and metabolic abnormalities, as well as increased morbidity and mortality in CHEU. The reasons for these disparities remain largely unknown. The present review focuses on a proposed link between immunometabolic aberrations and clinical pathologies observed in the rapidly expanding CHEU population. By drawing attention, firstly, to the significance of the immune and metabolic alterations observed in these children, and secondly, the impact of their healthcare requirements, particularly in low- and middle-income countries, this review aims to sensitize healthcare workers and policymakers about the long-term risks of in utero exposure to HIV and ART.

Surgical implications of HIV infection

According to the joint United Nations Programme on HIV/AIDS (UNAIDS), 37.7 million adults and children worldwide were estimated to be living with HIV or acquired immune deficiency syndrome (AIDS) at the end of 2020 [UNAIDS. (2022). http://www.unaids.org . Accessed 30 May 2022]. Most reside in low- and middle-income countries, with approximately 67% in sub-Saharan Africa (SSA). At the end of 2020, the total number of children less than 15 years of age living with HIV infection was 2.6 million, of whom 2.3 million (88%) were living in SSA. Aggressive interventions have reduced the annual number of incident (new) HIV infections among children to around 150,000 [UNAIDS. (2022). http://www.unaids.org . Accessed 30 May 2022]. However, paediatric HIV infection remains a pandemic affecting children predominantly in SSA but is also seen in Asia and sporadically elsewhere particularly in areas of civil strife such as is currently the case in Ukraine [War in Ukraine. (2022). https://www.unaids.org/en/War-Ukraine-special . Accessed Apr 2022]. New HIV infections among children declined by more than half (54%) from 2010 to 2020, due mainly to the increased provision of antiretroviral therapy to pregnant and breastfeeding women living with HIV [UNAIDS. (2022). http://www.unaids.org . Accessed 30 May 2022]. These programmes include early identification of HIV infection in pregnant or breastfeeding women through routine HIV testing, provision of antiretroviral therapy (ART) to all HIV-infected women who are pregnant or breastfeeding, provision of antiretroviral prophylaxis to their newborn infants during the first 6-12 weeks of life, delivery by elective Caesarean section when indicated, promotion of exclusive breastfeeding, early infancy screening for HIV infection, and initiation of ART in infants with HIV infection. HIV-infected children may require surgery either as an emergency to deal with a life-threatening incidental condition unrelated to HIV infection or for a complication of the disease such as tuberculosis or an aggressive soft tissue infection like necrotising fasciitis. Non-emergency surgical procedures may be required to assist in the diagnosis of an HIV-related condition or to correct a routine surgical problem electively. Surgical conditions associated with HIV infection are described under categories of soft tissue or organ-specific infections requiring drainage or debridement; gastrointestinal tract disease and complications; infections in the perineal area; malignancies and HIV-associated vasculitis. Although surgical outcomes are less favourable in HIV-infected children, pre-operative treatment of coinfections, administration of cotrimoxazole prophylaxis, nutritional support and antiretroviral therapy, together with peri-operative antibiotic prophylaxis have resulted in excellent short-term outcomes [World Health Organization. Consolidated guidelines on the use of antiretroviral drugs for treating and preventing HIV infection: Recommendations for a public health approach, June 201 http://www.apps.who.int/iris/bitstream/10665/85321/1/9789241505727_eng.pdf?ua=1 ; World Health Organization Guideline on when to start antiretroviral therapy and on pre-exposure prophylaxis for HIV, September 2015. http://www.apps.who.int/iris/bitstream/10665/186275/1/9789241509565_eng.pdf?ua=1;Eley et al. in BMC Infect Dis 2:3, 2002;Karpelowsky et al. in Pediatr Surg Int 28:1007-1014, 2012;].

Characterization of longitudinal nasopharyngeal microbiome patterns in maternally HIV-exposed Zambian infants

Background: Previous studies of infants born to HIV-positive mothers have linked HIV exposure to poor outcomes from gastrointestinal and respiratory illnesses, and to overall increased mortality rates. The mechanism behind this is unknown, but it is possible that differences in the nasopharyngeal (NP) microbiome between HIV-unexposed and HIV-exposed infants could play a role in perpetuating some outcomes. Methods: We conducted a longitudinal analysis of 170 NP swabs of healthy HIV-exposed, uninfected (HEU; n=10) infants and their HIV(+) mothers and HIV-unexposed, uninfected (HUU; n=10) infants and their HIV(-) mothers. These swabs were identified from a sample library collected in Lusaka, Zambia between 2015 and 2016. Using 16S rRNA gene sequencing, we characterized the maturation of the microbiome over the first 14 weeks of life to determine what quantifiable differences exist between HEU and HUU infants, and what patterns are reflected in the mothers' NP microbiomes. Results: In both HEU and HUU infants, Staphylococcus and Corynebacterium began as primary colonizers of the NP microbiome but were in time replaced by Dolosigranulum, Streptococcus, Moraxella and Haemophilus. When studying differences between infants, the microbe Staphylococcus haemolyticus indicated a distinctive high association with HIV exposure at birth, even when accounting for the interaction between HIV exposure status and time of sampling. When comparing infants to their mothers with paired analyses, HEU infants’ NP microbiome composition was only slightly different from their HIV(+) mothers at birth or 14 weeks, including in their carriage of S. pneumoniae, H. influenzae, and S. haemolyticus. Conclusions: Our analyses indicate that the HEU infants in our study exhibit subtle differences in the NP microbial composition throughout the sampling interval. Given our results and the sampling limitations of our study, we believe that further research must be conducted in order to confidently understand the relationship between HIV exposure and infants’ NP microbiomes.

HIV exposure and its association with paediatric ICU outcomes in children admitted with severe pneumonia at Chris Hani Baragwanath Academic Hospital, South Africa

Background. Pneumonia is one of the leading causes of under-5 death in South Africa and accounts for a substantial burden of paediatric intensive care unit (PICU) admissions. However, little is known about PICU outcomes in HIV-exposed uninfected (HIV-EU) children with pneumonia, despite the growing size of this vulnerable population.Objectives. To determine whether HIV exposure without infection is an independent risk factor for mortality and morbidity in childrenadmitted to PICU with pneumonia.Methods. This retrospective review included all patients with pneumonia admitted to the PICU at Chris Hani Baragwanath AcademicHospital between 1 January 2013 and 31 December 2014. Patients were classified as HIV-unexposed (HIV-U), HIV-EU and HIV-infected.Medical records were reviewed to determine survival to PICU discharge, duration of PICU admission and duration of mechanicalventilation. Survival analysis was used to determine the association between HIV infection/exposure with mortality, and linear regression was used to examine the association with length of stay and duration of mechanical ventilation. This study included 107 patients: 54 were HIV-U; 28 were HIV-EU; 23 HIV-positive; and 2 had an unknown HIV status.Results. Overall, 84% (n=90) survived to PICU discharge, with no difference in survival based on HIV infection or exposure. Both HIV-EUand HIV-U children had significantly shorter PICU admissions and fewer days of mechanical ventilation compared with HIV-infectedchildren (p=0.011 and p=0.004, respectively).Conclusion. HIV-EU children behaved similarly to HIV-U children in terms of mortality, duration of PICU admission and length ofmechanical ventilation. HIV infection was associated with prolonged length of mechanical ventilation and ICU stay but not increasedmortality

Evolution of the Gut Microbiome in HIV-Exposed Uninfected and Unexposed Infants during the First Year of Life

HIV-exposed uninfected infants (HEU) have abnormal immunologic functions and increased infectious morbidity in the first 6 months of life, which gradually decreases thereafter. The mechanisms underlying HEU immune dysfunctions are unknown. We hypothesized that unique characteristics of the HEU gut microbiota associated with maternal HIV status may underlie the HEU immunologic dysfunctions. We characterized the infant gut, maternal gut, and breast milk microbiomes of mother-infant pairs, including 123 with HEU and 117 with HIV-uninfected infants (HUU), from South Africa. Pan-bacterial 16S rRNA gene sequencing was performed on (i) infant stool at 6, 28, and 62 weeks; (ii) maternal stool at delivery and 62 weeks; and (iii) breast milk at 6 weeks. Infant gut alpha and beta diversities were similar between groups. Microbial composition significantly differed, including 12 genera, 5 families and 1 phylum at 6 weeks; 12 genera and 2 families at 28 weeks; and 2 genera and 2 families at 62 weeks of life. Maternal gut microbiomes significantly differed in beta diversity and microbial composition, and breast milk microbiomes differed in microbial composition only. Infant gut microbiotas extensively overlapped with maternal gut and minimally with breast milk microbiotas. Nevertheless, exclusively breastfed HEU and HUU had less divergent microbiomes than nonexclusively breastfed infants. Feeding pattern and maternal gut microbiome imprint the HEU gut microbiome. Compared to HUU, the HEU gut microbiome prominently differs in early infancy, including increased abundance of taxa previously observed to be present in excess in adults with HIV. The HEU and HUU gut microbiome compositions converge over time, mirroring the kinetics of HEU infectious morbidity risk.

Impaired functionality of antigen presenting cells in HIV- exposed uninfected infants in the first six months of life

HIV-exposed uninfected infants (HEU) have increased morbidity and mortality due to infections in the first 6 months of life that tapers down to 2 years of life. The underlying immunologic defects remain undefined. We investigated antigen-presenting cells (APC) by comparing the phenotype of unstimulated APC, responses to toll-like receptor (TLR) stimulation, and ability to activate natural killer (NK) cells in 24 HEU and 64 HIV-unexposed infants (HUU) at 1-2 days of life (birth) and 28 HEU and 45 HUU at 6 months of life. At birth, unstimulated APC showed higher levels of activation and cytokine production in HEU than HUU and stimulation with TLR agonists revealed lower expression of inflammatory cytokines and activation markers, but similar expression of IL10 regulatory cytokine, in APC from HEU compared to HUU. Differences were still present at 6 months of life. From birth to 6 months, APC underwent extensive phenotypic and functional changes in HUU and minimal changes in HEU. TLR stimulation also generated lower NK cell expression of CD69 and/or IFNγ in HEU compared with HUU at birth and 6 months. In vitro experiments showed that NK IFNγ expression depended on APC cytokine secretion in response to TLR stimulation. Ex vivo IL10 supplementation decreased APC-mediated NK cell activation measured by IFNγ expression. We conclude that APC maturation was stunted or delayed in the first 6 months of life in HEU compared with HUU. Deficient inflammatory APC responses and/or the imbalance between inflammatory and regulatory responses in HEU may play an important role in their increased susceptibility to severe infections.

Kinetics of pneumococcal antibodies among HIV-exposed, uninfected infants in Botswana

BACKGROUND

Streptococcus pneumoniae is a leading cause of severe infections among children. Despite vaccination, HIV-exposed, uninfected (HEU) children have a higher incidence of invasive pneumococcal disease than HIV-unexposed, uninfected (HUU) children. We sought to compare the immunogenicity of 13-valent pneumococcal conjugate vaccine (PCV-13) in HEU and HUU infants.

METHODS

We conducted a prospective cohort study of 134 mother-infant dyads in Botswana. Infants received PCV-13 doses at 2, 3, and 4 months through routine clinical care. We measured IgG antibodies specific to vaccine serotypes in sera collected from infants at 0, 5, and 12 months of age. We calculated the proportion of infants with protective IgG levels (≥0.35 µg/mL) to specific pneumococcal serotypes.

RESULTS

At birth, fewer than half of infants had protective IgG levels to serotypes 1 (38%), 3 (46%), 4 (33%), 5 (23%), 6B (40%), 7F (44%), 9 V (44%), and 23F (46%). Compared to HUU infants (n = 97), HEU infants (n = 37) had lower antibody concentrations at birth to serotypes 5 (p = 0.046) and 19A (p = 0.008) after adjustment for maternal age and infant birth weight. More than 80% of HEU and HUU infants developed protective antibody levels to each of the 13 vaccine serotypes following PCV-13 vaccination. Median concentrations of antibodies to pneumococcal serotypes declined by 55-93% between 5 and 12 months of age, with fewer than half of infants having protective antibody levels to serotypes 1 (47%), 3 (28%), 9 V (44%), 18C (24%), and 23F (49%) at 12 months of age.

CONCLUSIONS

Both HEU and HUU infants developed protective antibody responses to PCV-13 administered in a 3 + 0 schedule. However, antibody concentrations to many pneumococcal serotypes waned substantially by 12 months of age, suggesting that a PCV-13 booster dose in the second year of life may be needed to maintain protective pneumococcal antibody levels in older infants and young children.

Immunoglobulin G passive transfer from mothers to infants: total IgG, IgG subclasses and specific antipneumococcal IgG in 6-week Malawian infants exposed or unexposed to HIV

Background

The impaired transplacental passage of IgG from mothers living with HIV to their infants could be one of the causes of the high vulnerability to infections of HIV-exposed uninfected (HEU) infants, but controversial results have been obtained in different settings. The aim of this study was to assess in 6-week old HEU and HIV-unexposed, uninfected (HUU) Malawian infants the total IgG levels, the subclasses profile and the concentrations of global anti-pneumococcal capsular polysaccharide (anti-PCP) IgG and IgG2.

Methods

Dried blood spots were collected from 80 infants (40 HEU, 40 HUU) and antibodies concentrations determined by nephelometric method (total IgG and subclasses), or using ELISA (anti-PCP total IgG and IgG2). Results are expressed as median levels with IQR, while the proportions of each subclass out of the total IgG are used to describe the subclasses profile.

Results

At 6 weeks HEU infants had higher median levels of total IgG and IgG1 and a significantly lower level of IgG2 [0.376 (0.344–0.523) g/l vs 0.485 (0.374–0.781) g/l, p = 0.037] compared to the HUU counterparts. The IgG subclasses distribution confirmed the underrepresentation of IgG2 (IgG2 represented 5.82% of total IgG in HEU and 8.87% in HUU). The anti-PCP IgG and IgG2 levels were significantly lower in HEU infants [8.9 (5.4–15.1) mg/l vs 16.2 (9.61–25.8) mg/l in HUU, p < 0.001, and 2.69 (1.90–4.29) mg/l vs 4.47 (2.96–5.71) mg/l in HUU, p = 0.001, respectively].

Conclusion

Compared to HUU infants, HEU infants have IgG abnormalities mainly represented by low IgG2 levels, suggesting that despite maternal antiretroviral therapy, the mechanisms of IgG transplacental passage continue to be impaired in women living with HIV. HEU infants also showed a significantly lower level of specific anti-PCP IgG, possibly favouring a high vulnerability to S. pneumoniae infection at an age when protection is mostly depending on maternal IgG.

Non-diphtheriae Corynebacterium species are associated with decreased risk of pneumococcal colonization during infancy

Streptococcus pneumoniae (pneumococcus) is a leading cause of severe infections among children and adults. Interactions between commensal microbes in the upper respiratory tract and S. pneumoniae are poorly described. In this study, we sought to identify interspecies interactions that modify the risk of S. pneumoniae colonization during infancy and to describe development of the upper respiratory microbiome during infancy in a sub-Saharan African setting. We collected nasopharyngeal swabs monthly (0-6 months of age) or bimonthly (6-12 months of age) from 179 mother-infant dyads in Botswana. We used 16S ribosomal RNA gene sequencing to characterize the nasopharyngeal microbiome and identified S. pneumoniae colonization using a species-specific PCR assay. We detect S. pneumoniae colonization in 144 (80%) infants at a median age of 71 days and identify a strong negative association between the relative abundance of the bacterial genera Corynebacterium within the infant nasopharyngeal microbiome and the risk of S. pneumoniae colonization. Using in vitro cultivation experiments, we demonstrate growth inhibition of S. pneumoniae by secreted factors from strains of several Corynebacterium species isolated from these infants. Finally, we demonstrate that antibiotic exposures and the winter season are associated with a decline in the relative abundance of Corynebacterium within the nasopharyngeal microbiome, while breastfeeding is associated with an increase in the Corynebacterium relative abundance. Our findings provide novel insights into the interspecies interactions that contribute to colonization resistance to S. pneumoniae and suggest that the nasopharyngeal microbiome may be a previously unrecognized mechanism by which environmental factors influence the risk of pneumococcal infections during childhood. Moreover, this work lays the foundation for future studies seeking to use targeted manipulation of the nasopharyngeal microbiome to prevent infections caused by S. pneumoniae.

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.

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.

The Etiology of Pneumonia in HIV-uninfected South African Children: Findings From the Pneumonia Etiology Research for Child Health (PERCH) Study

BACKGROUND

Pneumonia is the major contributor to under 5 childhood mortality globally. We evaluated the etiology of pneumonia amongst HIV-uninfected South African children enrolled into the Pneumonia Etiology Research for Child Health case-control study.

METHODS

Cases, 1-59 months of age hospitalized with World Health Organization clinically defined severe/very severe pneumonia, were frequency-matched by age and season to community controls. Nasopharyngeal-oropharyngeal swabs were analyzed using polymerase chain reaction for 33 respiratory pathogens, and whole blood was tested for pneumococcal autolysin. Cases were also tested for Mycobacterium tuberculosis. Population etiologic fractions (EF) of pneumonia with radiologic evidence of consolidation/infiltrate were derived for each pathogen through Bayesian analysis.

RESULTS

Of the 805 HIV-uninfected cases enrolled based on clinical criteria, radiologically confirmed pneumonia was evident in 165 HIV-exposed, -uninfected, and 246 HIV-unexposed children. In HIV-exposed and HIV-unexposed children, respiratory syncytial virus was the most important pathogen with EFs of 31.6% [95% credible interval (CrI), 24.8%-38.8%] and 36.4% (95% CrI, 30.5%-43.1%), respectively. M. tuberculosis contributed EFs of 11.6% (95% CrI, 6.1%-18.8%) in HIV-exposed and 8.3% (95% CrI, 4.5%-13.8%) in HIV-unexposed children, including an EF of 16.3% (95% CrI, 6.1%-33.3%) in HIV-exposed children ≥12 months of age. Bacteremia (3.0% vs. 1.6%) and case fatality risk (3.6% vs. 3.7%) were similar in HIV-exposed and HIV-unexposed children.

CONCLUSIONS

Vaccination strategies targeting respiratory syncytial virus should be prioritized for prevention of pneumonia in children. Furthermore, interventions are required to address the high burden of tuberculosis in the pathogenesis of acute community-acquired pneumonia in settings such as ours.

Placental Vascular Abnormalities in Association With Prenatal and Long-Term Health Characteristics Among HIV-Exposed Uninfected Adolescents and Young Adults

BACKGROUND

HIV-exposed uninfected (HEU) individuals are predisposed to adverse health outcomes, which in part may stem from the influence of an altered intrauterine milieu on fetal programming. The placenta serves as a readout for the effects of the maternal environment on the developing fetus and may itself contribute to the pathogenesis of disease.

SETTING

US academic health system.

METHODS

We leveraged a previously established registry-based cohort of HEU adolescents and young adults to identify 26 subjects for whom placental histopathology was available. We further obtained placental tissue from 29 HIV-unexposed pregnancies for comparison. We examined differences in placental histopathology between the groups and related villous vascularity in the HEU group to prenatal maternal characteristics and long-term health outcomes.

RESULTS

Placentas from HEU pregnancies demonstrated a higher blood vessel count per villus as compared with controls (5.9 ± 1.0 vs. 5.4 ± 0.8; P = 0.05), which was independent of maternal prenatal age, race, body mass index, smoking status, hemoglobin, and gestational age. Furthermore, within the HEU group, lower CD4+ T-cell count during pregnancy was associated with greater placental vascularity (r = -0.44; P = 0.03). No significant relationships were observed between placental blood vessel count per villus and body mass index z-score or reactive airway disease among HEU individuals later in life.

CONCLUSIONS

Placentas from HEU pregnancies demonstrated increased villous vascularity compared with HIV-unexposed controls in proportion to the severity of maternal immune dysfunction. Further studies are needed to examine intrauterine exposure to hypoxia as a potential mechanism of fetal programming in HIV.

Respiratory Viral and Bacterial Factors That Influence Early Childhood Asthma

Asthma is a chronic respiratory condition characterised by episodes of shortness of breath due to reduced airway flow. The disease is triggered by a hyperreactive immune response to innocuous allergens, leading to hyper inflammation, mucus production, changes in structural cells lining the airways, and airway hyperresponsiveness. Asthma, although present in adults, is considered as a childhood condition, with a total of about 6.2 million children aged 18 and below affected globally. There has been progress in understanding asthma heterogeneity in adults, which has led to better patient stratification and characterisation of multiple asthma endotypes with distinct, but overlapping inflammatory features. The asthma inflammatory profile in children is not well-defined and heterogeneity of the disease is less described. Although many factors such as genetics, food allergies, antibiotic usage, type of birth, and cigarette smoke exposure can influence asthma development particularly in children, respiratory infections are thought to be the major contributing factor in poor lung function and onset of the disease. In this review, we focus on viral and bacterial respiratory infections in the first 10 years of life that could influence development of asthma in children. We also review literature on inflammatory immune heterogeneity in asthmatic children and how this overlaps with early lung development, poor lung function and respiratory infections. Finally, we review animal studies that model early development of asthma and how these studies could inform future therapies and better understanding of this complex disease.

Predictors of mortality in invasive pneumococcal disease: a meta-analysis

OBJECTIVES

To assess risk factors for mortality in invasive pneumococcal disease (IPD).

METHODS

We conducted a systemic literature search in January 2019. The main outcome measure included death within 30 days after diagnosis of IPD. The study protocol was registered in PROSPERO (CRD42019120189).

RESULTS

After reviewing 2514 potentially relevant records, remaining 190 articles were included in the analysis. A total of 228,782 IPD patients were identified and the mortality rate was 17.2% in the included articles. No significant evidence of publication bias was found according to the funnel plot and Egger's test (t = 1.464, p = 0.145). Male sex, older age, alcohol abuse, previous tuberculosis, meningitis, hospital acquired infections, multilobar infiltrate or effusion, Pitt bacteremia score≥4, Pneumonia Severity Index≥4, clinical conditions requiring intensive care, underlying clinical conditions, disease caused by serotypes 3, 6B, 9 N, 10A, 11A, 16 F, 17 F, 19, 19 F, 22 F, 23A, 23 F, 31 and 35 F, previous antibiotic use, inappropriate initial antibiotic therapy, penicillin resistance, and vancomycin use during the course of treatment were predicators of 30-day mortality.

CONCLUSIONS

This meta-analysis highlights important risk factors for IPD-related mortality, many of which may be targeted through preventive measures.

Preterm birth and severe morbidity in hospitalized neonates who are HIV exposed and uninfected compared with HIV unexposed

OBJECTIVES

Infants who are HIV exposed but uninfected (HEU) compared with HIV unexposed uninfected (HUU) have an increased risk of adverse birth outcomes, morbidity and hospitalization. In the era of universal maternal antiretroviral treatment, there are few insights into patterns of neonatal morbidity specifically.

DESIGN

A prospective cohort study.

METHODS

We compared neonatal hospitalizations among infants who were HEU (n = 463) vs. HUU (n = 466) born between 2017 and 2019 to a cohort of pregnant women from a large antenatal clinic in South Africa. We examined maternal and infant factors associated with hospitalization using logistic regression.

RESULTS

Hospitalization rates were similar between neonates who were HEU and HUU (13 vs. 16%; P = 0.25). Overall, most hospitalizations occurred directly after birth (87%); infection-related causes were identified in 34%. The most common reason for hospitalization unrelated to infection was respiratory distress (25%). Very preterm birth (<32 weeks) (29 vs. 11%; P = 0.01) as well as very low birthweight (<1500 g) (34 vs. 16%; P = 0.02) occurred more frequently among hospitalized neonates who were HEU. Of those hospitalized, risk of intensive care unit (ICU) admission was higher in neonates who were HEU (53%) than HUU (27%) [risk ratio = 2.1; 95% confidence interval (95% CI) 1.3-3.3]. Adjusted for very preterm birth, the risk of ICU admission remained higher among neonates who were HEU (aRR = 1.8; 95% CI 1.1-2.9).

CONCLUSION

Neonates who were HEU (vs. HUU) did not have increased all-cause or infection-related hospitalization. However, very preterm birth, very low birthweight and ICU admission were more likely in hospitalized neonates who were HEU, indicating increased severity of neonatal morbidity.

Identifying Infants and Young Children at Risk of Unplanned Hospital Admissions and Clinic Visits in Dar es Salaam, Tanzania

BACKGROUND

Pediatric inpatient mortality rates are as high as 11% in parts of sub-Saharan Africa. Unscheduled clinic visits also burden children in sub-Saharan Africa. Our objective was to identify factors associated with hospital admissions and unscheduled clinic visits among Tanzanian children < 24 months of age.

METHODS

We conducted a secondary analysis of 2 trials conducted in Dar es Salaam, Tanzania. We performed univariate and Poisson multivariable regression analyses to identify factors associated with hospital admissions and unscheduled clinic visits.

RESULTS

Of 4784 children < 24 months of age, 293 (6.1%) were hospitalized at least once and 1308 (27.3%) had ≥ 1 unscheduled clinic visit. Infants and children who were exposed to but HIV-negative had increased risk of hospital admission [adjusted risk ratios (aRR): 3.67; 95% CI: 2.45-5.50; P < 0.001] compared with HIV-unexposed children. Those who were HIV-positive had even higher risk of hospital admission compared with those not exposed to HIV (aRR: 10.87; 95% CI: 7.01-16.89; P < 0.001). Birth weight and breast-feeding status were not associated with increased risk of hospital admission. Children with Apgar scores < 7 (aRR: 1.32; 95% CI: 1.03-1.69; P = 0.001), not exclusively breast-fed up to 6 months of age (aRR: 1.34; 95% CI: 1.12-1.60; P = 0.001), and who were HIV-exposed and HIV-negative (aRR: 2.35; 95% CI: 2.08-2.66; P < 0.001) or HIV-positive (aRR: 3.02; 95% CI: 2.52-3.61; P < 0.001) had higher risk of unscheduled clinic visits.

CONCLUSIONS

Exposure to HIV and being HIV-positive were associated with the greatest risk for hospital admission and unplanned clinic visits among infants and children in Tanzania. Targeting these vulnerable populations in interventional studies may reduce morbidity.

Divergent serotype replacement trends and increasing diversity in pneumococcal disease in high income settings reduce the benefit of expanding vaccine valency

Streptococcus pneumoniae is a significant cause of otitis media, pneumonia, and meningitis. Only seven of the approximately 100 serotypes were initially included in the pneumococcal polysaccharide conjugate vaccine (PCV) in 2000 before it was expanded in subsequent years. Although the invasive pneumococcal disease (IPD) incidence due to vaccine serotypes (VT) has declined, partial replacement by non-vaccine serotypes (NVT) was observed following widespread vaccine uptake. We conducted a trend analysis assembling the available evidence for PCV impact on European, North American and Australian national IPD. Significant effectiveness against VT IPD in infants was observed, although the impact on national IPD incidence varied internationally due to serotype replacement. Currently, NVT serotypes 8, 9N, 15A and 23B are increasing in the countries assessed, although a variety of other NVTs are affecting each country and age group. Despite these common emerging serotypes, there has not been a dominant IPD serotype post-vaccination as there was pre-vaccination (serotype 14) or post-PCV7 (serotype 19A), suggesting that future vaccines with additional serotypes will be less effective at targeting and reducing IPD in global populations than previous PCVs. The rise of diverse NVTs in all settings’ top-ranked IPD-causing serotypes emphasizes the urgent need for surveillance data on serotype distribution and serotype-specific invasiveness post-vaccination to facilitate decision making concerning both expanding current vaccination programmes and increasing vaccine valency.

Diagnosis and management of community-acquired pneumonia in children: South African Thoracic Society guidelines

BACKGROUND

Pneumonia remains a major cause of morbidity and mortality amongst South African children. More comprehensive immunisation regimens, strengthening of HIV programmes, improvement in socioeconomic conditions and new preventive strategies have impacted on the epidemiology of pneumonia. Furthermore, sensitive diagnostic tests and better sampling methods in young children improve aetiological diagnosis.

OBJECTIVES

To produce revised guidelines for pneumonia in South African children under 5 years of age.

METHODS

The Paediatric Assembly of the South African Thoracic Society and the National Institute for Communicable Diseases established seven expert subgroups to revise existing South African guidelines focusing on: (i) epidemiology; (ii) aetiology; (iii) diagnosis; (iv) antibiotic management and supportive therapy; (v) management in intensive care; (vi) prevention; and (vii) considerations in HIV-infected or HIVexposed, uninfected (HEU) children. Each subgroup reviewed the published evidence in their area; in the absence of evidence, expert opinion was accepted. Evidence was graded using the British Thoracic Society (BTS) grading system. Sections were synthesized into an overall guideline which underwent peer review and revision.

RECOMMENDATIONS

Recommendations include a diagnostic approach, investigations, management and preventive strategies. Specific recommendations for HIV infected and HEU children are provided.

VALIDATION

The guideline is based on available published evidence supplemented by the consensus opinion of SA paediatric experts. Recommendations are consistent with those in published international guidelines.

Association of In Utero HIV Exposure With Obesity and Reactive Airway Disease in HIV-Negative Adolescents and Young Adults

BACKGROUND

HIV-negative individuals with in utero HIV exposure represent an emerging population, exceeding 18 million people worldwide. Long-term clinical outcomes among HIV-exposed uninfected (HEU) individuals into adolescence and young adulthood remain unknown.

SETTING

US academic health system.

METHODS

In this observational cohort study, we leveraged a patient data registry to identify 50 HEU adolescents and young adults. We also identified 141 HIV-unexposed controls that were matched to HEU subjects up to 3:1 on age of last encounter (±2 years), birthdate (±5 years), sex, race/ethnicity, and zip code. All subjects were born since January 1, 1990, with medical records available into adolescence and young adulthood. Primary outcomes were most recent body mass index (BMI) z-score and presence of reactive airway disease (RAD). Records were manually reviewed to extract health information.

RESULTS

Fifty HEU adolescents and young adults (18 ± 3 years, 54% men) and 141 matched controls (19 ± 3 years, 54% men) were compared. HEU individuals had a higher BMI z-score (1.12 ± 1.08 vs. 0.73 ± 1.09, P = 0.03) and an increased prevalence of obesity (42% vs. 22%, P = 0.009) compared with controls. HEU subjects also had a higher prevalence of RAD vs. controls (40% vs. 23%, P = 0.03). These differences persisted on adjusting for demographic, socioeconomic, maternal, and birth-related factors. Maternal prenatal CD4 T-cell count was inversely associated with BMI z-score among HEU adolescents (r = -0.47, P = 0.01).

CONCLUSIONS

HEU adolescents and young adults exhibited a heightened prevalence of obesity and RAD compared with HIV-unexposed controls. Additional studies are needed to optimize care for the expanding population of HEU individuals transitioning to adulthood.

Contemporary Issues in Pregnancy (and Offspring) in the Current HIV Era

PURPOSE OF REVIEW

Although antiretroviral therapy (ART) has dramatically reduced mother to child transmission of HIV, data continue to mount that infants exposed to HIV in utero but are not infected (HEU) have serious negative health consequences compared to unexposed infants. This review evaluates recent literature on contemporary issues related to complications seen in pregnant women with HIV and their offspring.

RECENT FINDINGS

Current studies show that HEU infants are at a high risk of adverse outcomes, including premature birth, poor growth, neurodevelopmental impairment, immune dysfunction, infectious morbidity, and death. Etiologies for the observed clinical events and subclinical alterations are complex and multifactorial, and the long-term consequences of many findings are yet unknown. HEU infants have an unacceptable rate of morbidity and mortality from perinatal HIV and ART exposure, even in the modern ART era. Continual monitoring and reporting is imperative to protect this vulnerable population in our everchanging landscape of HIV treatment and prevention.

Growth and Neurodevelopment of HIV-Exposed Uninfected Children: a Conceptual Framework

Purpose of Review

The population of HIV-exposed uninfected (HEU) children is expanding rapidly, and over one million HEU infants are born each year globally. Several recent studies have reported that HEU children, particularly in low- and middle-income countries, are at risk of poor outcomes, including impaired growth and neurodevelopment. However, the reasons for poor clinical outcomes amongst HEU children remain unclear.

Recent Findings

We summarise the findings from recent large studies that have characterised growth and neurodevelopment in HEU children, identified risk factors and explored underlying mechanistic pathways. We propose a conceptual framework to explain how exposure to HIV and antiretroviral therapy (ART) may lead to adverse growth and neurodevelopment in uninfected children, and review the available evidence and research gaps.

Summary

We propose that HEU children are affected both indirectly, through the augmentation of universal risk factors underlying poor growth and neurodevelopment, and directly through HIV/ART-specific pathways, which ultimately may converge through a series of common pathogenic mechanisms. In the era of universal ART, a better understanding of these pathways is crucial to inform future prevention and intervention strategies.

Initiation of Antiretroviral Therapy Before Pregnancy Reduces the Risk of Infection-related Hospitalization in Human Immunodeficiency Virus-exposed Uninfected Infants Born in a High-income Country

BACKGROUND

Epidemiological studies conducted in low- and high-income countries showed that infants exposed to maternal human immunodeficiency virus (HIV) have a high risk of severe infections. Immune alterations during fetal life have been proposed as a possible mechanism.

METHODS

This prospective study assessed the relative risk of hospitalization for infection in HIV-exposed uninfected (HEU) infants as compared to HIV-unexposed (HU) infants born in a high-income country (HIC). Markers of monocyte activation and levels of pathogen-specific antibodies were measured at birth to identify correlates of infant susceptibility.

RESULTS

There were 27 of 132 HEU infants and 14 of 123 HU infants hospitalized for infection during the first year of life (adjusted hazard ratio [aHR] 2.33, 95% confidence interval [CI] 1.10-4.97). Most of this increased risk was associated with the time of initiation of maternal antiretroviral therapy (ART). As compared to HU infants, the risk of hospitalization for infection of HEU infants was 4-fold higher when mothers initiated ART during pregnancy (aHR 3.84, 95% CI 1.69-8.71) and was not significantly increased when ART was initiated before pregnancy (aHR 1.42, 95% CI 0.58-3.48). The activation of newborn monocytes and the reduced transfer of maternal antibodies were most intense following ART initiation during pregnancy, and predicted the risk of infant hospitalization.

CONCLUSIONS

These observations indicate that initiation of maternal ART before pregnancy reduces the susceptibility of HEU infants born in a HIC to severe infections, and that this effect could be related to the prevention of immune alterations during fetal life.

The Role of Human Immunodeficiency Virus in Influenza- and Respiratory Syncytial Virus-associated Hospitalizations in South African Children, 2011-2016

BACKGROUND

Data describing influenza- or respiratory syncytial virus (RSV)-associated hospitalized illness in children aged <5 years in Africa are limited.

METHODS

During 2011-2016, we conducted surveillance for severe respiratory illness (SRI) in children aged <5 years in 3 South African hospitals. Nasopharyngeal aspirates were tested for influenza and RSV using real-time reverse transcription polymerase chain reaction. We estimated rates of influenza- and RSV-associated hospitalized SRI by human immunodeficiency virus (HIV) status and compared children who tested positive for influenza vs RSV using multivariable penalized logistic regression.

RESULTS

Among 3650 hospitalized children, 203 (5.6%) tested positive for influenza viruses, 874 (23.9%) for RSV, and 19 (0.5%) for both. The median age of children hospitalized with influenza was 13.9 months vs 4.4 months for RSV (P < .01). Annual influenza-associated hospitalization rates per 100000 were highest among infants aged 6-11 months (545; 95% confidence interval [CI], 409-703), while RSV-associated hospitalization rates were highest in infants aged 0-2 months (6593; 95% CI, 5947-7217). HIV exposure was associated with increased incidence of influenza- and RSV-associated hospitalization in infants aged 0-5 months, with relative risk (RR) 2.2 (95% CI, 1.4-3.4) and 1.4 (95% CI, 1.3-1.6), respectively. HIV infection was associated with increased incidence of influenza- and RSV-associated hospitalization in all age groups; RR 2.7 (95% CI, 2.0-3.5) and 3.8 (95% CI, 3.1-4.8), respectively.

CONCLUSIONS

Influenza- and RSV-associated hospitalizations are common among South African infants. HIV infection and HIV exposure in infants increase risk of influenza- and RSV-associated hospitalization.

Maternal and child health outcomes in rural South African mothers living with and without HIV

In the era of widespread antiretroviral therapy (ART), consequences of being HIV-exposed is unclear for children, especially in rural communities. A population sample of consecutive births (470/493) in the Eastern Cape of South Africa (SA) were recruited and reassessed at five points over the first 24 months. Maternal and child outcomes between mothers living with and without HIV were assessed using multiple linear and logistic regressions. At birth, 28% of the sample was mothers living with HIV and five additional mothers seroconverted. All mothers living with HIV reported taking ART. The rate of depressed mood and IPV was similar across serostatus. However, mothers living with HIV significantly decreased their alcohol use after learning about their pregnancy and were more likely to exclusively breastfeed when compared to mothers without HIV. Despite maternal HIV status, children had similar growth across the first 24 months of life. Future work is needed to assess if these developmental trajectories will persist.

Impact of HIV and antiretroviral drug exposure on lung growth and function over 2 years in an African Birth Cohort

Supplemental Digital Content is available in the text

Objective:

To assess the impact of HIV and antiretroviral exposure without infection on lung growth and function over the first 2 years of life.

Design:

Prospective observational study of an African birth cohort, Drakenstein Child Health Study.

Method:

Infants enrolled antenatally had lung function measured at 6 weeks, 1 and 2 years. HIV-infected women received antiretroviral therapy (ART) as per local guidelines. The association between HIV and antiretroviral exposure with lung function was assessed using mixed effects modelling.

Results:

Of 1143 infants born, two HIV-infected infants were excluded from analysis; 909 (80%) infants had lung function collected at 6 weeks [190 (21%) were HIV-exposed uninfected (HEU)]; 782 (69%) at 1 year and 741 (65%) at 2 years. At 6 weeks HEU infants had larger tidal volume compared with HIV-unexposed infants (1.13 ml, confidence interval: 0.02–2.23, P = 0.045). High maternal viral load was associated with a 17% lower expiratory flow over 2 years (0.17, confidence interval 0.00–0.34, P = 0.046). First-line ART initiated during pregnancy was associated with lower infant tidal volume at 6 weeks compared with those who initiated ART before pregnancy (−2.7 ml, −5.31 to −0.10, P = 0.042), and low maternal CD4⁺ cell counts associated with lower infant tidal over 2 years (−11.1 ml, −18.58–3.58, P = 0.004).

Conclusion:

HIV exposure is associated with altered lung function in early life, with a vulnerable HEU subgroup based on maternal disease severity, immunological compromise and ART exposure. These data highlight the importance of ongoing surveillance of respiratory health in HEU children.

Streptococcus pneumoniae colonization in pneumococcal vaccine-naïve human immunodeficiency virus-exposed infected and -uninfected South African children

Pneumococcal nasopharyngeal colonization is a pre-requisite for pneumococcal disease; the risk for pneumococcal disease is high in children born to women living with human immunodeficiency virus (HIV). We investigated pneumococcal colonization, serotype distribution and antibiotic susceptibility of Streptococcus pneumoniae isolates carried by perinatal HIV-infected and HIV-exposed-uninfected (HEU) children.Serial nasopharyngeal swabs were collected from 331 HIV-infected and 491 HEU children, at up to 6 scheduled timepoints, between median ages of 25 to 181 weeks. Pneumococcus was identified by culture; serotyping and antibiotic susceptibility testing were done by conventional methods. No pneumococcal vaccine was given.HIV-infected children were less likely to be colonized with 7-valent pneumococcal conjugate vaccine 7 serotypes than HEU at a median of 25 weeks of age (23% vs 36%; P < .001); however, no differences in colonization between the 2 groups were observed at subsequent study-visits. Over the 36-months study-period pneumococcal colonization increased in both HIV-infected (from 45% to 77%) and HEU (from 57% to 61%) children. Over the study-period, pneumococcal isolates non-susceptible to cotrimoxazole decreased from 92% to 57% and had a similar trend to penicillin (from 65% to 42%) in HIV-infected children. Similarly, pneumococcal nonsusceptible to cotrimoxazole decreased from 93% to 57% and to penicillin from 69% to 37% in HEU children.Vaccine serotype colonization was common in this population and similar rates were observed in HIV-infected and HEU children. The prevalence of pneumococcal isolates non-susceptible to cotrimoxazole and penicillin decreased with age.

Association of maternal HIV-1 severity with dental caries: an observational study of uninfected 5- to 7-yr-old children of HIV-1-infected mothers without severe immune suppression

Treatment programs to prevent perinatal and postnatal HIV-1 transmission have become available in sub-Saharan Africa, leading to an emerging population of HIV-1 exposed uninfected (HEU) children. Exposure to HIV-1 in utero and during breastfeeding may increase the risk of morbidity and mortality in HEU children. This study estimated the association of the severity of maternal HIV-1 infection as assessed by CD4 count and viral load at baseline (7 d postpartum), with  dmft count of their 5- to 7-yr-old HEU offspring. A follow-up study was conducted of HIV-1-infected mother-HEU children pairs (n = 164) from the Ugandan site of the ANRS 12341-PROMISE- PEP trial (ClinicalTrials.gov, number NCT00640263). HIV-1-infected mothers were interviewed and the HEU children were examined for caries using the World Health Organization's survey methods for field conditions and the dmft index. Directed acyclic graphs and negative binomial regression were used for analyses. The prevalence of 1 or more dmft was 48%. Negative binomial regression showed no association between the dmft count and maternal CD4 counts 7 d postpartum but a 10% lower dmft count with longer breastfeeding duration was found. Maternal CD4 count at birth was not associated with the dental caries experience in uninfected children born to women without severe immune suppression, while there appeared to be a protective effect of high viral load and breastfeeding duration.

Immune Activation and Microbial Translocation Markers in HIV-Exposed Uninfected Malawian Infants in the First Year of Life

BACKGROUND

HIV-exposed uninfected (HEU) infants show a high rate of morbidity. We aimed to investigate on biomarkers of immune activation/microbial translocation in HEU infants, evaluating the impact that infections/malnutrition can have on biomarker levels during the first year of life.

METHODS

Clinical data of 72 Malawian infants were recorded monthly and correlated with levels of soluble CD14 (sCD14), lipopolysaccharide-binding protein (LBP) and intestinal fatty acid-binding protein (I-FABP), analyzed longitudinally.

RESULTS

Levels of sCD14 and LBP showed a significant age-related increase. Higher levels of LBP (19.4 vs. 15.2 μg/ml) were associated with stunting, affecting 30% of the infants. The association remained statistically significant after adjusting for cytomegalovirus acquisition, malaria and respiratory infections (p = 0.031). I-FABP levels were significantly increased in infants experiencing gastrointestinal infections (1442.8 vs. 860.0 pg/ml, p = 0.018).

CONCLUSION

We provide evidence that stunting is associated with an enhanced inflammatory response to microbial products in HEU children, suggesting that malnutrition status should be taken into consideration to better understand the alteration of the immune profile of HEU infants living in poor socioeconomic settings.

Prevalence of Immunodeficiency in Children With Invasive Pneumococcal Disease in the Pneumococcal Vaccine Era: A Systematic Review

IMPORTANCE

Despite increasing access to vaccination, invasive pneumococcal disease (IPD) is responsible for approximately 826 000 deaths worldwide in children younger than 5 years each year. To allow early identification and prevention, an improved understanding of risk factors for IPD is needed.

OBJECTIVES

To review the literature on the prevalence of primary immunodeficiency (PID) in children younger than 18 years presenting with IPD without another predisposing condition and to inform guidelines for immunologic evaluation after the first episode of IPD based on published evidence.

EVIDENCE REVIEW

A literature search of PubMed, Embase (inception [1974] to February 28, 2019), and MEDLINE (inception [1946] to February 28, 2019) was conducted using the terms Streptococcus pneumonia, Streptococcus pneumoniae, pneumococcal infection, Streptococcus infection, pneumococcal meningitis, immunodeficiency, immune response, immunocompromised, susceptib*, precursor, predispose*, recurren*, newborn, neonat*, infan*, toddler, child, preschooler, adolescen*, and pediatric. Publications reporting original data on immunodeficiency in children with microbiologically confirmed primary or recurrent IPD were included. Strength of clinical data was graded according to the 5-point scale of the Oxford Centre for Evidence-Based Medicine.

FINDINGS

In 6022 unique children with primary IPD, 5 of 393 (1.3%) to 17 of 162 (10.5%) of all children and 14 of 53 (26.4%) of those older than 2 years had a PID identified. Higher rates of PID, up to 10 of 15 (66.7%), were found in children with recurrent IPD. Antibody deficiency was the most common immunodeficiency, followed by complement deficiency, asplenia, and rarer defects in T-cell signaling. The site of infection was a key indicator for the risk of underlying PID, with the greatest risk of PID in children with meningitis or complicated pneumonia.

CONCLUSIONS AND RELEVANCE

Results of this study suggest that invasive pneumococcal disease, and particularly recurrent IPD, is an important marker of underlying PID in children without other risk factors. The findings also suggest that children older than 2 years with pneumococcal meningitis or complicated pneumonia and all children with recurrent IPD should be referred for an immune evaluation.

TRIAL REGISTRATION

PROSPERO identifier: CRD42017075978.

Pneumococcus nasopharyngeal carriage in children attending an academic hospital in Pretoria, South Africa, after the introduction of pneumococcal vaccine

Background

In 2009, pneumococcal conjugate vaccine was introduced in South Africa. However, there are concerns that this could lead to an increase in colonisation of non-vaccine serotypes (serotype replacement).

Methods

In a cross-sectional study, 350 children aged 1 month to 14 years were enrolled at Dr George Mukhari Academic Hospital from December 2015 to April 2016. We assessed the prevalence of nasopharyngeal colonisation with pneumococcus and characterised the serotypes found.

Results

The median age of the cohort was 33.7 months (interquartile range 16.27–69.5 months), with 20% being < 1 year. A total of 21% of the children were diagnosed with pneumococcal-related conditions; among these, pneumonia was the most common condition. Less than half (43%) of the participants were fully immunised. Forty-six (13%) of the children were colonised with pneumococcus. Younger age was significantly associated with pneumococcal colonisation. Among those colonised with pneumococcus, 35% were fully immunised, 30% were partially immunised, 30% had an unknown immunisation status and 4% were unimmunised. Eight (17%) of the children who were colonised with pneumococcus had pneumococcal-related conditions. The commonest serotype identified was 6A/B. Overall, 2% of the cohort were colonised with vaccine-serotype pneumococcus.

Conclusion

As a minority of children had evidence of nasopharyngeal colonisation with vaccine-serotype pneumococci, serotype replacement may be emerging in our population.

Effectiveness of pneumococcal conjugate vaccination against invasive pneumococcal disease among children with and those without HIV infection: a systematic review and meta-analysis

Background

HIV-infected children are at a higher risk of Invasive Pneumococcal Disease (IPD) and its mortality, even in the era of antiretroviral therapy. Therefore, an effective vaccination strategy would be beneficial. To investigate the effectiveness of Pneumococcal Conjugate Vaccination (PCV) against IPD among HIV-Infected and HIV-Uninfected Children through a systematic review and meta-analysis.

Methods

Observational studies and randomized trials on 7 years old or older children were searched in the Cochrane Library, Web of Science core collection, Embase, Medline/PubMed, and Google Scholar. Critical appraisal was done using the Cochrane risk of bias tool and the Newcastle-Ottawa quality assessment form. Effectiveness and efficacy of at least one dose of PCV was investigated among children with and without HIV considering subgroups of pneumococcal serotypes. We meta-analyzed the effect sizes using random-effects modeling.

Results

Efficacy of PCV was estimated as 45.0% (31.2, 56.1) and 52.6% (25.7, 69.8) among HIV-infected and HIV-uninfected children, respectively. Effectiveness of PCV among HIV-infected children as − 6.2% (− 67.6, 32.7) was significantly lower than HIV-uninfected children 65.1% (47.3, 76.9). Effectiveness of PCV among HIV-infected children for IPDs caused by vaccine serotypes was estimated as 7.7(− 66.7, 48.9), and for IPDs caused by non-vaccine serotypes was estimated as − 402.8(− 1856, − 29.2).

Conclusion

Unlike the evidence on the efficacy of PCV against IPD among both of HIV-infected and HIV-uninfected children, its effectiveness against IPD among HIV-infected children is much less limited.

Review registration

The study protocol was registered at PROSPERO (registration ID: CRD42018108187).

Electronic supplementary material

The online version of this article (10.1186/s12879-019-4325-4) contains supplementary material, which is available to authorized users.

In Utero Efavirenz Exposure and Neurodevelopmental Outcomes in HIV-exposed Uninfected Children in Botswana

BACKGROUND

Minimal data exist related to neurodevelopment after in utero exposure to Efavirenz (EFV). We sought to compare neurodevelopmental outcomes in HIV-exposed/uninfected (HEU) children with in utero exposure to EFV-based triple antiretroviral treatment (ART) versus non-EFV-based ART, and to examine whether timing of initial EFV exposure is associated with neurodevelopment deficits.

METHODS

Women living with HIV who had received EFV-based ART during pregnancy and whose HEU newborn participated in a prior study were reconsented for their HEU toddler to undergo neurodevelopmental testing at 24 months old. We administered the Bayley Scales of Infant and Toddler Development, Third Edition (BSID-III), Developmental Milestones Checklist (DMC) and Profile of Social Emotional Development (PSED). We compared outcomes to previously-collected data from a cohort of 24-month-old HEU children with in utero exposure to non-EFV-based ART. Adjusted general linear models were used to compare mean outcomes.

RESULTS

Our analysis included 493 HEU children (126 EFV-exposed, 367 EFV-unexposed). Adjusted mean scores for the EFV-exposed group were worse than the EFV-unexposed group on BSID-III Receptive Language (adjusted means = 21.5 vs. 22.5, P = 0.05), DMC Locomotor (30.7 vs. 32.0, P < 0.01) and Fine Motor scales (17.8 vs. 19.2, P < 0.01); and PSED (11.7 vs. 9.9, P = 0.02); but better on the DMC Language scale (17.6 vs. 16.5, P = 0.01). Earlier (vs. later) EFV exposure was associated with worse scores on the BSID-III Receptive Language scale (20.7 vs. 22.2, P = 0.02).

CONCLUSIONS

HEU children exposed in utero to EFV-based ART may be at higher risk for neurodevelopmental and social-emotional deficits than HEU children exposed to non-EFV-based ART.

Burden of Streptococcus pneumoniae and Haemophilus influenzae type b disease in children in the era of conjugate vaccines: global, regional, and national estimates for 2000-15

Background

Pneumococcal conjugate vaccine (PCV) and Haemophilus influenzae type b (Hib) vaccine are now used in most countries. To monitor global and regional progress towards improving child health and to inform national policies for disease prevention and treatment, we prepared global, regional, and national disease burden estimates for these pathogens in children from 2000 to 2015.

Methods

Using WHO and Maternal and Child Epidemiology Estimation collaboration country-specific estimates of pneumonia and meningitis mortality and pneumonia morbidity from 2000 to 2015, we applied pneumococcal and Hib cause-specific proportions to estimate pathogen-specific deaths and cases. Summary estimates of the proportion of pneumonia deaths and cases attributable to these pathogens were derived from four Hib vaccine and six PCV efficacy and effectiveness study values. The proportion of meningitis deaths due to each pathogen was derived from bacterial meningitis aetiology and adjusted pathogen-specific meningitis case–fatality data. Pneumococcal and Hib meningitis cases were inferred from modelled pathogen-specific meningitis deaths and literature-derived case–fatality estimates. Cases of pneumococcal and Hib syndromes other than pneumonia and meningitis were estimated using the ratio of pathogen-specific non-pneumonia, non-meningitis cases to pathogen-specific meningitis cases from the literature. We accounted for annual HIV infection prevalence, access to care, and vaccine use.

Findings

We estimated that there were 294 000 pneumococcal deaths (uncertainty range [UR] 192 000–366 000) and 29 500 Hib deaths (18 400–40 700) in HIV-uninfected children aged 1–59 months in 2015. An additional 23 300 deaths (15 300–28 700) associated with pneumococcus and fewer than 1000 deaths associated Hib were estimated to have occurred in children infected with HIV. We estimate that pneumococcal deaths declined by 51% (7–74) and Hib deaths by 90% (78–96) from 2000 to 2015. Most children who died of pneumococcus (81%) and Hib (76%) presented with pneumonia. Less conservative assumptions result in pneumococcccal death estimates that could be as high as 515 000 deaths (302 000–609 000) in 2015. Approximately 50% of all pneumococcal deaths in 2015 occurred in four countries in Africa and Asia: India (68 700 deaths, UR 44 600–86 100), Nigeria (49 000 deaths, 32 400–59 000), the Democratic Republic of the Congo (14 500 deaths, 9300–18 700), and Pakistan (14 400 deaths, 9700–17 000]). India (15 600 deaths, 9800–21 500), Nigeria (3600 deaths, 2200–5100), China (3400 deaths, 2300–4600), and South Sudan (1000 deaths, 600–1400) had the greatest number of Hib deaths in 2015. We estimated 3·7 million episodes (UR 2·7 million–4·3 million) of severe pneumococcus and 340 000 episodes (196 000–669 000) of severe Hib globally in children in 2015.

Interpretation

The widespread use of Hib vaccine and the recent introduction of PCV in countries with high child mortality is associated with reductions in Hib and pneumococcal cases and deaths. Uncertainties in the burden of pneumococcal disease are largely driven by the fraction of pneumonia deaths attributable to pneumococcus. Progress towards further reducing the global burden of Hib and pneumococcal disease burden will depend on the efforts of a few large countries in Africa and Asia.

Funding

Bill & Melinda Gates Foundation.

HIV-Exposed Uninfected Infants Have Increased Regulatory T Cells That Correlate With Decreased T Cell Function

Background: HIV-exposed uninfected infants (HEU) are at higher risk of severe infections, hospitalizations and death compared with HIV-unexposed uninfected infants (HUU), but the immune deficit underlying it is not known. To address this gap, we investigated T cell functionality and its relationship to phenotypic profiles of T cells and antigen presenting cells (APC) in HEU and HUU.

Methods: Blood mononuclear cells from 55 HEU and 16 HUU were stimulated with Staphylococcal Enterotoxin B (SEB) or mock for 72 h, and tested by flow cytometry for proliferation and expression of Th1, Th2, and regulatory (Treg) markers. In parallel, cells were phenotypically assessed for differentiation profiles of Treg, conventional T cell (Tconv) and APC in unstimulated cells.

Results: HEU had lower CD4+ functional responses to SEB/mock and similar CD8+ responses compared with HUU. In the phenotypic T cell panel, HEU showed higher proportions of CD4+ and CD8+ Treg expressing IL10, FOXP3, and CD25; higher effector Tconv and Treg; and lower naïve and CD4+TGFβ+ Treg compared with HUU. In the phenotypic APC panel, HEU showed higher proportions of CD1c+ cDC2, CD123+ pDC, CD16+ inflammatory monocytes and cDC and higher expression of CD103 on CD1c-CD123-CD16-cDC1 compared with HUU. Regression analyses adjusted for HIV exposure and multiple comparisons showed that higher CD8+IL10+ and CD8+FOXP3+ Treg in unstimulated cells were associated with lower CD8+ T cell functional responses to SEB/mock. Functionality was not affected by Tconv differentiation, but higher APC activation in aggregate was associated with higher CD8+IL10+ Treg responses to SEB.

Conclusions: T cell functionality was decreased in HEU compared with HUU. High CD8+ Treg proportions were the most important predictors of decreased T cell functionality in HEU and HUU.

Maternal immunisation to improve the health of HIV-exposed infants

HIV-exposed but uninfected (HEU) infants are at an increased risk of many infectious diseases that can contribute to the high mortality seen among HEU children. Maternal immunisation could be a promising strategy to reduce infections in HEU infants. However, very little research has explored the effect of HIV on the immunogenicity and effectiveness of vaccines given during pregnancy. We review the available evidence on maternal immunisation among women living with HIV (WLWH) for all vaccines recommended, considered, or being investigated for routine or risk-based use during pregnancy. Of the 11 vaccines included, only three have been investigated in WLWH. Available evidence suggests that maternal HIV infection limits the immunogenicity of several vaccines, leaving HEU infants more susceptible to infection during their first few months of life. Whether maternal immunisation reduces the infectious morbidity and mortality associated with infectious diseases in HEU children remains unknown. We conclude the Review by identifying future research priorities.

Factors Associated with Lower Respiratory Tract Infections in HIV-Exposed Uninfected Infants

To identify factors that predispose human immunodeficiency virus (HIV)-exposed uninfected infants (HEUs) to higher incidence of severe infections, hospitalization, and death in the first 6-24 months of life compared with HEUs with and without lower respiratory tract infection (LRTI) in the first 6 months of life. Nested case-control study of 107 LRTI+ infants enrolled in the International Site Development Initiative (NISDI) Perinatal and Longitudinal Study in Latin American Countries (LILAC) studies with and 140 LRTI- in the first 6 months, matched by date and place of birth. Infants and mothers had plasma antibodies measured against respiratory syncytial virus (RSV), parainfluenza (PIV) 1, 2, 3, influenza, and pneumococcus 1, 5, 6B, and 14. Compared with LRTI-, mothers of LRTI+ HEUs had lower years of education, lower CD4⁺ cells, and higher HIV plasma viral load at delivery, but similar use of antiretrovirals and cotrimoxazole and other sociodemographic characteristics. LRTI+ and LRTI- HEUs had similar demographic and hematological characteristics and antibody concentrations against respiratory pathogens at birth. At 6 months, the rates of seroconversions to respiratory pathogens and antibody responses to tetanus vaccine were also similar. However, antibody concentrations to RSV were significantly higher in LRTI+ compared with LRTI- HEUs and marginally higher to PIV1. Maternal factors associated with advanced HIV disease, but unrelated to the use of antiretrovirals, cotrimoxazole, or the level of maternal antibodies against respiratory pathogens, contribute to the increased risk of LRTI in HEUs. In HEUs, antiretroviral and cotrimoxazole use, exposure to respiratory pathogens and humoral immune responses were not associated with the incidence of LRTI.

Contribution of Maternal Antiretroviral Therapy and Breastfeeding to 24-Month Survival in Human Immunodeficiency Virus-Exposed Uninfected Children: An Individual Pooled Analysis of African and Asian Studies

Background

Human immunodeficiency virus (HIV)-infected pregnant women increasingly receive antiretroviral therapy (ART) to prevent mother-to-child transmission (PMTCT). Studies suggest HIV-exposed uninfected (HEU) children face higher mortality than HIV-unexposed children, but most evidence relates to the pre-ART era, breastfeeding of limited duration, and considerable maternal mortality. Maternal ART and prolonged breastfeeding while on ART may improve survival, although this has not been reliably quantified.

Methods

Individual data on 19 219 HEU children from 21 PMTCT trials/cohorts undertaken from 1995 to 2015 in Africa and Asia were pooled to estimate the association between 24-month mortality and maternal/infant factors, using random-effects Cox proportional hazards models. Adjusted attributable fractions of risks computed using the predict function in the R package "frailtypack" were used to estimate the relative contribution of risk factors to overall mortality.

Results

Cumulative incidence of death was 5.5% (95% confidence interval, 5.1-5.9) by age 24 months. Low birth weight (LBW <2500 g, adjusted hazard ratio (aHR, 2.9), no breastfeeding (aHR, 2.5), and maternal death (aHR, 11.1) were significantly associated with increased mortality. Maternal ART (aHR, 0.5) was significantly associated with lower mortality. At the population level, LBW accounted for 16.2% of 24-month mortality, never breastfeeding for 10.8%, mother not receiving ART for 45.6%, and maternal death for 4.3%; combined, these factors explained 63.6% of deaths by age 24 months.

Conclusions

Survival of HEU children could be substantially improved if public health practices provided all HIV-infected mothers with ART and supported optimal infant feeding and care for LBW neonates.

Low Birth Weight in Human Immunodeficiency Virus-Exposed Uninfected Infants in Bronx, New York

BACKGROUND

Prevention of mother-to-child transmission of human immunodeficiency virus (HIV) with antiretroviral therapy (ART) has been highly successful. However, HIV-exposed uninfected (HIV-EU) infants might be at increased risk for low birth weight and/or preterm birth. We compared the birth weights and gestational ages of HIV-EU infants to those of HIV-unexposed control infants in Bronx, New York, an epicenter of the HIV epidemic in the United States.

METHODS

This study was performed with a retrospective cohort of HIV-EU infants born at Montefiore Medical Center between 2008 and 2012 and HIV-unexposed control infants. Each HIV-EU infant was matched according to year of birth with 5 HIV-unexposed controls from the New York City Department of Health and Mental Hygiene birth certificate database. We used regression models to assess the association between HIV exposure and birth weight while controlling for potential confounders. A secondary analysis was performed to determine the association of maternal protease inhibitor-based ART use and birth weight among HIV-EU infants.

RESULTS

We included 155 HIV-EU infants born between 2008 and 2012 (51% female, 61% black, 32% Hispanic) and 775 HIV-unexposed infants. The mean (± standard deviation) unadjusted birth weights were 2971 ± 616 g (HIV-EU infants) and 3163 ± 644 g (HIV-unexposed infants) (P < .01). Multivariable regression revealed significantly lower birth weight for the HIV-EU infants (difference, -101.5 g [95% confidence interval, -181.4 to -21.6]). We found no difference in mean birth weight or gestational age with maternal protease inhibitor-based ART use when compared to the use of other regimens.

CONCLUSIONS

We found significantly lower birth weight among HIV-EU infants. Long-term prospective studies are necessary to determine the implications of this finding on infant growth and development.

B and T Cell Phenotypic Profiles of African HIV-Infected and HIV-Exposed Uninfected Infants: Associations with Antibody Responses to the Pentavalent Rotavirus Vaccine

We examined associations between B and T cell phenotypic profiles and antibody responses to the pentavalent rotavirus vaccine (RV5) in perinatally HIV-infected (PHIV) infants on antiretroviral therapy and in HIV-exposed uninfected (PHEU) infants enrolled in International Maternal Pediatric Adolescent AIDS Clinical Trials P1072 study (NCT00880698). Of 17 B and T cell subsets analyzed, PHIV and PHEU differed only in the number of CD4+ T cells and frequency of naive B cells, which were higher in PHEU than in PHIV. In contrast, the B and T cell phenotypic profiles of PHIV and PHEU markedly differed from those of geographically matched contemporary HIV-unexposed infants. The frequency of regulatory T and B cells (Treg, Breg) of PHIV and PHEU displayed two patterns of associations: FOXP3+ CD25+ Treg positively correlated with CD4+ T cell numbers; while TGFβ+ Treg and IL10+ Treg and Breg positively correlated with the frequencies of inflammatory and activated T cells. Moreover, the frequencies of activated and inflammatory T cells of PHIV and PHEU positively correlated with the frequency of immature B cells. Correlations were not affected by HIV status and persisted over time. PHIV and PHEU antibody responses to RV5 positively correlated with CD4+ T cell counts and negatively with the proportion of immature B cells, similarly to what has been previously described in chronic HIV infection. Unique to PHIV and PHEU, anti-RV5 antibodies positively correlated with CD4+/CD8+FOXP3+CD25+% and negatively with CD4+IL10+% Tregs. In conclusion, PHEU shared with PHIV abnormal B and T cell phenotypic profiles. PHIV and PHEU antibody responses to RV5 were modulated by typical HIV-associated immune response modifiers except for the association between CD4+/CD8+FOXP3+CD25+Treg and increased antibody production.