OBJECTIVES:To develop a population pharmacokinetic (popPK) model to understand factors affecting the broadly neutralizing HIV antibody (bNAb) VR07-523LS disposition and infant predicted serum neutralization 80% inhibitory dilution titre ratio (PT80) and its potential relationship to antiviral effects. METHODS:PK data from two studies were used: infants exposed to HIV initiating therapy ≤5 days of age (IMPAACT P1112, n = 21) and healthy adults (VRC605, n = 25). The infant study implemented fixed subcutaneous (s.c.) dosing whereas the adult study implemented weight-based dosing, via both intravenous (i.v.) and s.c. routes. Monte Carlo simulation assessed two doses (80 mg followed by 100 mg at 12 weeks) to determine the maintenance of levels >10 µg/mL in virtual infants. The broadly neutralizing antibodies (bNAbs) concentration/IC80 ratio (PT80) was calculated on the basis of simulated concentrations from the popPK model and VRC07-523LS HIV-1 sensitivity (IC80) distribution. RESULTS:This model predicts typical infant CL/F and t1/2 of 159 mL/day/70 kg and 39 days. Comparatively, predicted adult typical CL/F and t1/2 were 269 mL/day/70 kg and 31 days. Concentrations were >10 µg/mL in >87% of virtual infants at 12 weeks following one dose and >98% at 24 weeks following two doses. Median (90% predictive interval) PT80 was 163 (71-383), 116 (51-274) and 61 (26-144) at 6, 8 and 12 weeks, respectively. Significant model covariates included age (infant versus adult) and multiple dosing. CONCLUSIONS:Age and repeat dosing influence VRC07-523LS PK. An 80-mg dose followed by 100 mg at 12 weeks rapidly achieves and maintains concentrations >10 µg/mL for >24 weeks. This dosing strategy is expected to result in antiviral effects in patients with sensitive viruses and supports further evaluation of VRC07-523LS.

Youth living with HIV (YLWH) face psychosocial challenges and HIV-related stigma, which impact adherence to antiretroviral therapy (ART). This study was designed to understand better the change in mental health symptoms and experiences with stigma among YLWH in Tanzania who completed the original pilot Sauti ya Vijana (SYV), a mental health and life skills group intervention. YLWH who completed SYV and demonstrated a change of ≥2 points in either direction on their Patient Health Questionnaire PHQ-9 (depression screener) from baseline to 18 months were purposively sampled. HIV Stigma was measured using 10-questions from the Berger HIV Stigma Scale, and findings ranged from 4-16 for internal stigma and 6-24 for external stigma. In-depth interviews (IDI) were conducted in Kiswahili and included topics such as history of mental health challenges, perceptions of stigma, and experiences with the SYV intervention. Interviews were transcribed, translated to English, and analyzed for emergent themes. Ten youth, 18-25 years of age, were interviewed; 70% were male. Mean (SD) PHQ-9 scores were 7.3 (SD = 3.5) at baseline and 5.6 (SD = 5.0) at 18 months. All participants reported experiencing intermittent episodes of mental health challenges due to difficult interpersonal relationships and fear of stigma. Youth relied on peer support and skills from the SYV intervention to cope with mental health challenges and stigma. Participants reported fear of being stigmatized by others, which led to behaviors such as skipping medication or avoiding situations for worry about unintentional disclosure. All participants endorsed experiencing external stigma on the HIV stigma scale; however, only 3 of 10 participants reported experiencing enacted stigma when directly asked to describe an experience during in-depth interviews. Participants described how SYV helped them have "more confidence", accept themselves, and incorporate positive coping skills such as relaxation (deep breathing) when they felt stressed. The findings suggest SYV helped YLWH accept themselves, develop positive coping methods, and identify and form peer social support; but stigma remains common. Descriptions of stigma were not recognized as such; experiences of enacted stigma were acknowledged by some participants. More research is needed to understand and measure mental distress and wellness as well as stigma in this population so that interventions may more accurately detect change in key outcomes.

ABSTRACT Background Children living with HIV (CLWH) are at high risk of colonization and infection by bacterial respiratory pathogens. Microbes in the upper respiratory microbiome can prevent colonization by these pathogens. The impact of HIV infection on development of the upper respiratory microbiome during childhood is poorly understood. Methods We enrolled healthy CLWH (<5 years) and age- and sex-matched HIV-exposed, uninfected (HEU) and HIV-unexposed, uninfected (HUU) children in a cross-sectional study conducted in Botswana. We used shotgun metagenomic sequencing to compare the nasopharyngeal microbiomes of children by HIV status. Findings Of 143 children, 44 were CLWH, 49 were HEU, and 50 were HUU. Nasopharyngeal microbiome composition differed by HIV status (p=0·043, R 2 =0·019). The relative abundance of Corynebacterium pseudodiphtheriticum was lower in CLWH compared to HEU and HUU children (p=0·01). Among CLWH, a low (<25%) CD4+ cell percentage was associated with microbiome composition (p=0·009, R 2 =0·042) and lower relative abundances of Corynebacterium propinquum (p=0·003), C. pseudodiphtheriticum (p=0·007), and Dolosigranulum pigrum (p=0·004). The relative abundances of C. propinquum, C. pseudodiphtheriticum and D. pigrum in the nasopharyngeal microbiome were negatively correlated with the abundances of Streptococcus pneumoniae and Staphylococcus aureus . Interpretation CLWH with HIV-associated immunosuppression have altered nasopharyngeal microbiome composition and lower abundances of bacterial species associated with respiratory health during childhood. These findings suggest that the upper respiratory microbiome may contribute to the high risk of bacterial respiratory infections among CLWH. Funding National Institutes of Health, Duke Center for AIDS Research, Penn Center for AIDS Research RESEARCH IN CONTEXT Evidence before this study We searched PubMed for research articles published from database inception through November 20, 2022, using the terms (“nasopharyngeal” OR “nasal” OR “upper respiratory”) AND (“HIV” OR “human immunodeficiency virus”) AND (“microbiome” OR “microbiota”) AND (“pediatric” OR “child” OR “children” OR “infants”). This search returned five articles, three of which collected nasopharyngeal specimens from children living with HIV (CLWH). The objective of two of these articles was pathogen identification using culture- and polymerase chain reaction-based methods. The remaining study characterized the nasopharyngeal microbiomes of children with pneumonia, children with upper respiratory infections, and healthy children in Botswana using 16S rRNA sequencing. Genera associated with respiratory health were less abundant in CLWH with pneumonia, but no data was available for healthy CLWH. Thus, it remained unknown if the microbiome alterations observed in CLWH were associated with HIV or with pneumonia. Added value of this study To our knowledge, this is the first study to investigate the nasopharyngeal microbiome in healthy CLWH using metagenomic sequencing. To account for shifts in the microbiome that occur with age, we enrolled age- and sex-matched HIV-exposed, uninfected and HIV-unexposed children for each CLWH. The use of shotgun metagenomic sequencing allowed us to investigate differences in the microbiome at the species level. We found that HIV infection and HIV-associated immunosuppression were associated with an altered nasopharyngeal microbiome and a lower abundance of species associated with respiratory health and resistance to colonization by common bacterial respiratory pathogens. Implications of all the available evidence These findings suggest that HIV-associated alterations in the nasopharyngeal microbiome may predispose CLWH to colonization by bacterial respiratory pathogens responsible for invasive infection and death. Strategies to reduce pathogen colonization through modification of the microbiome hold promise for reducing infectious morbidity and mortality in CLWH.

Children living with HIV (CLWH) are at high risk of colonization and infection by respiratory pathogens, though this risk can be reduced by other microbes in the upper respiratory microbiome. The impact of HIV infection on the pediatric upper respiratory microbiome is poorly understood, and we sought to address this knowledge gap by identifying associations between HIV infection and the nasopharyngeal microbiomes of Batswana children. We enrolled Batswana CLWH (<5 years) and age- and sex-matched HIV-exposed, uninfected and HIV-unexposed, uninfected children in a cross-sectional study. We used shotgun metagenomic sequencing to compare nasopharyngeal microbiomes by HIV status. Among the 143 children in this study, HIV and HIV-associated immunosuppression were associated with alterations in nasopharyngeal microbiome composition, including lower abundances of Corynebacterium species associated with resistance to bacterial pathogen colonization. These findings suggest that the upper respiratory microbiome may contribute to the high risk of respiratory infections among CLWH.

The mechanisms by which respiratory viruses predispose to secondary bacterial infections remain poorly characterized. Using 2,409 nasopharyngeal swabs from 300 infants enrolled in a prospective cohort study in Botswana, we perform a detailed analysis of factors that influence the dynamics of bacterial pathobiont colonization during infancy. We quantify the extent to which viruses increase the acquisition of Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae. We provide evidence of cooperative interactions between these pathobionts while identifying host characteristics and environmental exposures that influence the odds of pathobiont colonization during early life. Using 16S rRNA gene sequencing, we demonstrate that respiratory viruses result in losses of putatively beneficial Corynebacterium and Streptococcus species that are associated with a lower odds of pathobiont acquisition. These findings provide important insights into viral-bacterial relationships in the upper respiratory tract of direct relevance to respiratory infections and suggest that the bacterial microbiota is a potentially modifiable mechanism by which viruses promote bacterial respiratory infections.

BACKGROUND:Vertical HIV-1 transmission despite antiretroviral therapy may be mitigated by the use of long-acting, broadly neutralizing, monoclonal antibodies (bNAb) such as VRC07-523LS. The present study was designed to determine the safety and pharmacokinetics of VRC07-523LS. METHODS:VRC07-523LS, 80 mg/dose, was administered subcutaneously after birth to non-breastfed (cohort 1; N = 11, enrolled in USA) and breastfed (cohort 2; N = 11, enrolled in South Africa and Zimbabwe) infants exposed to HIV-1. Breastfed infants (cohort 2) received a second 100-mg dose at 12 weeks if still receiving breastmilk. All infants received antiretroviral prophylaxis in addition to VRC07-523LS. VRC07-523LS levels were compared to VRC01 levels, as determined previously in this study. RESULTS:Local reactions (all grade ≤ 2) occurred after dose 1 in 18% of infants in cohort 1 and after doses 1 and 2 in 100% of infants in cohort 2. The VRC07-523LS dose at birth (mean 26 mg/kg) achieved a mean ± SD plasma level of 222.3 ± 71.6 mcg/mL by 24 hours and 18.4 ± 7.2 mcg/mL at week 12, prior to dose 2. The pre-established target of ≥ 10 mcg/mL at week 12 was met in 94% of infants. The terminal half-life of VRC07-523LS was observed to be 39.2 ± 5.0 days. At week 4 and week 8, bNAb levels were significantly higher (P ≤ .002) after one dose of VRC07-523LS, compared to one dose of VRC01 (20 mg/kg). No infant included in the study acquired HIV-1. CONCLUSIONS:VRC07-523LS was well tolerated with pharmacokinetics that support further studies of potent long-acting bNAbs together with antiretrovirals to prevent HIV-1 acquisition in infants.

BACKGROUND:Approximately 130 000 infants acquire HIV annually despite global maternal antiretroviral therapy scale-up. We evaluated the potential clinical impact and cost-effectiveness of offering long-acting, anti-HIV broadly neutralizing antibody (bNAb) prophylaxis to infants in three distinct settings. METHODS:We simulated infants in Côte d'Ivoire, South Africa, and Zimbabwe using the Cost-Effectiveness of Preventing AIDS Complications-Pediatric (CEPAC-P) model. We modeled strategies offering a three-bNAb combination in addition to WHO-recommended standard-of-care oral prophylaxis to infants: a) with known, WHO-defined high-risk HIV exposure at birth (HR-HIVE); b) with known HIV exposure at birth (HIVE); or c) with or without known HIV exposure (ALL). Modeled infants received 1-dose, 2-doses, or Extended (every 3 months through 18 months) bNAb dosing. Base case model inputs included 70% bNAb efficacy (sensitivity analysis range: 10-100%), 3-month efficacy duration/dosing interval (1-6 months), and $20/dose cost ($5-$100/dose). Outcomes included pediatric HIV infections, life expectancy, lifetime HIV-related costs, and incremental cost-effectiveness ratios (ICERs, in US$/year-of-life-saved [YLS], assuming a ≤ 50% GDP per capita cost-effectiveness threshold). FINDINGS:The base case model projects that bNAb strategies targeting HIVE and ALL infants would prevent 7-26% and 10-42% additional pediatric HIV infections, respectively, compared to standard-of-care alone, ranging by dosing approach. HIVE-Extended would be cost-effective (cost-saving compared to standard-of-care) in Côte d'Ivoire and Zimbabwe; ALL-Extended would be cost-effective in South Africa (ICER: $882/YLS). BNAb strategies targeting HR-HIVE infants would result in greater lifetime costs and smaller life expectancy gains than HIVE-Extended. Throughout most bNAb efficacies and costs evaluated in sensitivity analyses, targeting HIVE infants would be cost-effective in Côte d'Ivoire and Zimbabwe, and targeting ALL infants would be cost-effective in South Africa. INTERPRETATION:Adding long-acting bNAbs to current standard-of-care prophylaxis would be cost-effective, assuming plausible efficacies and costs. The cost-effective target population would vary by setting, largely driven by maternal antenatal HIV prevalence and postpartum incidence.

The mechanisms by which respiratory viruses predispose to secondary bacterial infections remain poorly characterized. Using 2,409 nasopharyngeal swabs from 300 infants in Botswana, we performed a detailed analysis of factors that influence the dynamics of bacterial pathobiont colonization during infancy. We quantify the extent to which viruses increase the acquisition of Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae. We provide evidence of cooperative interactions between these pathobionts while identifying host characteristics and environmental exposures that influence the odds of pathobiont colonization during early life. Using 16S rRNA gene sequencing, we demonstrate that respiratory viruses result in losses of putatively beneficial Corynebacterium and Streptococcus species that are associated with a lower odds of pathobiont acquisition. These findings provide novel insights into viral-bacterial relationships in the URT of direct relevance to respiratory infections and suggest that the URT bacterial microbiota is a potentially modifiable mechanism by which viruses promote bacterial respiratory infections.

Background In 2012, Botswana introduced 13-valent pneumococcal conjugate vaccine (PCV-13) to its childhood immunization program in a 3+0 schedule, achieving coverage rates of above 90% by 2014. In other settings, PCV introduction has been followed by an increase in carriage or disease caused by non-vaccine serotypes, including some serotypes with a high prevalence of antibiotic resistance. Methods We characterized the serotype epidemiology and antibiotic resistance of pneumococcal isolates cultured from nasopharyngeal samples collected from infants (≤12 months) in southeastern Botswana between 2016 and 2019. Capsular serotyping was performed using the Quellung reaction. E-tests were used to determine minimum inhibitory concentrations for common antibiotics. Results We cultured 264 pneumococcal isolates from samples collected from 150 infants. At the time of sample collection, 81% of infants had received at least one dose of PCV-13 and 53% had completed the three-dose series. PCV-13 serotypes accounted for 27% of isolates, with the most prevalent vaccine serotypes being 19F (n = 20, 8%), 19A (n = 16, 6%), and 6A (n = 10, 4%). The most frequently identified non-vaccine serotypes were 23B (n = 29, 11%), 21 (n = 12, 5%), and 16F (n = 11, 4%). Only three (1%) pneumococcal isolates were resistant to amoxicillin; however, we observed an increasing prevalence of penicillin resistance using the meningitis breakpoint (2016: 41%, 2019: 71%; Cochran-Armitage test for trend, p = 0.0003) and non-susceptibility to trimethoprim-sulfamethoxazole (2016: 55%, 2019: 79%; p = 0.04). Three (1%) isolates were multi-drug resistant. Conclusions PCV-13 serotypes accounted for a substantial proportion of isolates colonizing infants in Botswana during a four-year period starting four years after vaccine introduction. A low prevalence of amoxicillin resistance supports its continued use as the first-line agent for non-meningeal pneumococcal infections. The observed increase in penicillin resistance at the meningitis breakpoint and the low prevalence of resistance to ceftriaxone supports use of third-generation cephalosporins for empirical treatment of suspected bacterial meningitis.

BackgroundCoformulated bictegravir, emtricitabine, and tenofovir alafenamide is a single-tablet regimen and was efficacious and well tolerated in children and adolescents with HIV (aged 6 years to <18 years) in a 48-week phase 2/3 trial. In this study, we report data from children aged at least 2 years and weighing 14 kg to less than 25 kg.MethodsWe conducted this open-label, multicentre, multicohort, single-arm study in South Africa, Thailand, Uganda, and the USA. Participants were virologically suppressed children with HIV, aged at least 2 years, weighing 14 kg to less than 25 kg. Participants received bictegravir (30 mg), emtricitabine (120 mg), and tenofovir alafenamide (15 mg) once daily, switching to bictegravir (50 mg), emtricitabine (200 mg), and tenofovir alafenamide (25 mg) upon attaining a bodyweight of at least 25 kg. The study included pharmacokinetic evaluation at week 2 to confirm the dose of coformulated bictegravir, emtricitabine, and tenofovir alafenamide for this weight band by comparing with previous adult data. Primary outcomes were bictegravir area under the curve over the dosing interval (AUCtau) and concentration at the end of the dosing interval (Ctau) at week 2, and incidence of treatment-emergent adverse events and laboratory abnormalities until the end of week 24 in all participants who received at least one dose of bictegravir, emtricitabine, and tenofovir alafenamide. This study is registered with ClinicalTrials.gov, NCT02881320.FindingsOverall, 22 participants were screened (from Nov 14, 2018, to Jan 11, 2020), completed treatment with bictegravir, emtricitabine, and tenofovir alafenamide (until week 48), and entered an extension phase. The geometric least squares mean (GLSM) ratio for AUCtau for bictegravir was 7·6% higher than adults (GLSM ratio 107·6%, 90% CI 96·7–119·7); Ctau was 34·6% lower than adults (65·4%, 49·1–87·2). Both parameters were within the target exposure range previously found in adults, children, or both”. Grade 3–4 laboratory abnormalities occurred in four (18%) participants by the end week 24 and six (27%) by the end of week 48. Drug-related adverse events occurred in three participants (14%) by the end of week 24 and week 48; none were severe. No Grade 3–4 adverse events, serious adverse events, or adverse events leading to discontinuation occurred by the end of week 24 and week 48.InterpretationData support the use of single-tablet coformulated bictegravir (30 mg), emtricitabine (120 mg), and tenofovir alafenamide (15 mg) for treatment of HIV in children aged at least 2 years and weighing 14 kg to less than 25 kg.FundingGilead Sciences.

Background: Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory illness among young children. Human immunodeficiency virus (HIV)-exposed, uninfected (HEU) children experience a higher burden of RSV disease and have immune abnormalities that may influence their responses to live-attenuated RSV vaccines. Methods: In a pooled analysis of clinical trials of 7 live-attenuated, intranasal RSV vaccines conducted by the IMPAACT Network among children 6 to <25 months of age with serum RSV-neutralizing titers of <1:40, the infectivity and immunogenicity of these vaccines were compared among HEU and HIV-unexposed, uninfected (HUU) children. Nasal washes were collected during the first 28 days after vaccination. Serum RSV-neutralizing and anti-RSV F glycoprotein immunoglobulin G (IgG) antibodies were measured prior to and 56 days after vaccination, and before and after the following winter season. Results: Of 156 children, 90 (58%) were HUU and 66 (42%) were HEU. Seventy-six (84%) HUU and 63 (95%) HEU participants were infected with vaccine (shed vaccine virus and/or had a >= 4-fold rise in serum RSV antibodies at 56 days after vaccination). HUU children had higher serum RSV-neutralizing and anti-RSV F IgG titers prior to vaccination. Compared to HEU children, lower percentages of HUU children had >= 4-fold rises in RSV-neutralizing (67% vs 88%) and anti-RSV F IgG (70% vs 89%) titers at 56 days after vaccination. Conclusions: Live-attenuated RSV vaccines are highly immunogenic in HEU children. Given their increased burden of RSV disease and higher early childhood mortality in some settings, HEU children should be prioritized for vaccination against RSV as these vaccines become available.

ABSTRACT Introduction Approximately 130 000 infants acquire HIV annually despite global maternal antiretroviral therapy scale-up. We evaluated the potential clinical impact and cost-effectiveness of offering long-acting, anti-HIV broadly neutralizing antibody (bNAb) prophylaxis to infants in three distinct settings. Methods We simulated infants in Côte d’Ivoire, South Africa, and Zimbabwe using the Cost-Effectiveness of Preventing AIDS Complications-Pediatric (CEPAC-P) model. We modeled strategies offering a three-bNAb combination in addition to WHO-recommended standard-of-care oral prophylaxis to infants: a) with known, WHO-defined high-risk HIV exposure at birth ( HR-HIVE ); b) with known HIV exposure at birth ( HIVE ); or c) with or without known HIV exposure ( ALL ). Modeled infants received 1-dose , 2-doses , or Extended (every 3 months through 18 months) bNAb dosing. Base case model inputs included 70% bNAb efficacy (sensitivity analysis range: 10-100%), 3-month efficacy duration/dosing interval (1-6 months), and $20/dose cost ($5-$100/dose). Outcomes included pediatric HIV infections, life expectancy, lifetime HIV-related costs, and incremental cost-effectiveness ratios (ICERs, in US$/year-of-life-saved [YLS], assuming a < 50% GDP per capita cost-effectiveness threshold). Results The base case model projects that bNAb strategies targeting HIVE and ALL infants would prevent 7-26% and 10-42% additional pediatric HIV infections, respectively, compared to standard-of-care alone, ranging by dosing approach. HIVE-Extended would be cost-effective (cost-saving compared to standard-of-care) in Côte d’Ivoire and Zimbabwe; ALL-Extended would be cost-effective in South Africa (ICER: $882/YLS). BNAb strategies targeting HR-HIVE infants would result in greater lifetime costs and smaller life expectancy gains than HIVE-Extended . Throughout most bNAb efficacies and costs evaluated in sensitivity analyses, targeting HIVE infants would be cost-effective in Côte d’Ivoire and Zimbabwe, and targeting ALL infants would be cost-effective in South Africa. Discussion Adding long-acting bNAbs to current standard-of-care prophylaxis would be cost-effective, assuming plausible efficacies and costs. The cost-effective target population would vary by setting, largely driven by maternal antenatal HIV prevalence and postpartum incidence.

Abstract Introduction Infant HIV prophylaxis with broadly neutralizing anti‐HIV antibodies (bNAbs) could provide long‐acting protection against vertical transmission. We sought to estimate the potential clinical impact and cost‐effectiveness of hypothetical bNAb prophylaxis programmes for children known to be HIV exposed at birth in three sub‐Saharan African settings. Methods We conducted a cost‐effectiveness analysis using the CEPAC‐Pediatric model, simulating cohorts of infants from birth through death in Côte d'Ivoire, South Africa and Zimbabwe. These settings were selected to reflect a broad range of HIV care cascade characteristics, antenatal HIV prevalence and budgetary constraints. We modelled strategies targeting bNAbs to only WHO‐designated “high‐risk” HIV‐exposed infants (HR‐HIVE) or to all HIV‐exposed infants (HIVE). We compared four prophylaxis approaches within each target population: standard of care oral antiretroviral prophylaxis (SOC), and SOC plus bNAbs at birth (1‐dose), at birth and 3 months (2‐doses), or every 3 months throughout breastfeeding (Extended). Base‐case model inputs included bNAb efficacy (60%/dose), effect duration (3 months/dose) and costs ($60/dose), based on published literature. Outcomes included paediatric HIV incidence and incremental cost‐effectiveness ratios (ICERs) calculated from discounted life expectancy and lifetime HIV‐related costs. Results The model projects that bNAbs would reduce absolute infant HIV incidence by 0.3–2.2% (9.6–34.9% relative reduction), varying by country, prophylaxis approach and target population. In all three settings, HR‐HIVE–1‐dose would be cost‐saving compared to SOC. Using a 50% GDP per capita ICER threshold, HIVE‐Extended would be cost‐effective in all three settings with ICERs of $497/YLS in Côte d'Ivoire, $464/YLS in South Africa and $455/YLS in Zimbabwe. In all three settings, bNAb strategies would remain cost‐effective at costs up to $200/dose if efficacy is ≥30%. If the bNAb effect duration were reduced to 1 month, the cost‐effective strategy would become HR‐HIVE–1‐dose in Côte d'Ivoire and Zimbabwe and HR‐HIVE–2‐doses in South Africa. Findings regarding the cost‐effectiveness of bNAb implementation strategies remained robust in sensitivity analyses regarding breastfeeding duration, maternal engagement in postpartum care, early infant diagnosis uptake and antiretroviral treatment costs. Conclusions At current efficacy and cost estimates, bNAb prophylaxis for HIV‐exposed children in sub‐Saharan African settings would be a cost‐effective intervention to reduce vertical HIV transmission.

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 lg/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 con-centrations 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.(c) 2022 Elsevier Ltd. All rights reserved.

Background: Youth living with human immunodeficiency virus (YLWH) are vulnerable to incomplete adherence to antiretroviral therapy in the context of stigma, decreased hope for future, and mental health challenges. Despite these challenges, few mental health interventions have been developed to support YLWH. Previous randomized results from the Sauti ya Vijana (SYV; "The Voice of Youth") mental health intervention were indicative of the intervention's benefits in promoting virologic suppression. Methods: SYV is a group-based mental health and life skills intervention (pilot, individually randomized group treatment trial) developed alongside YLWH. SYV was comprised of 10, 90-minute sessions based on evidence-based treatment models designed to improve coping, social support, and hope for future as a pathway to improved adherence and virologic suppression. At baseline, YLWH 12 to 24 years of age were randomized to SYV or standard of care. Participants included in this secondary analysis were enrolled in SYV's crossover waves due to either being randomized to standard of care or inability to attend an earlier group, and therefore delayed intervention exposure. Measured outcomes included self-reported mental health measures, self-reported human immunodeficiency virus measures (stigma and adherence), and human immunodeficiency virus ribonucleic acid. Data was collected at baseline, preintervention, and postintervention timepoints. Participants were included if they attended a crossover wave and had data at all 3 timepoints. Results: Twenty-one crossover participants met inclusion criteria. Mean scores of self-reported mental health questionnaires were in an asymptomatic range both pre- and postintervention. Viral suppression was N = 15 (71%) preintervention compared to N = 17 (81%) postintervention. The participants who became virologically suppressed had no change in antiretroviral therapy. Conclusions: Despite the small sample size, findings from this study demonstrate that mental wellbeing may be an important pathway to improved HIV outcomes for YLWH. The same trend toward virologic suppression pre- to postintervention was demonstrated in the randomized pilot trial and suggests that SYV holds promise to improve HIV outcomes. Data from this analysis support the fully powered trial that is now underway.

Pneumococcal conjugate vaccines reduce the burden of invasive pneumococcal disease, but the sustained effect of these vaccines can be diminished by an increase in disease caused by non-vaccine serotypes. To describe pneumococcal serotype epidemiology in Botswana following introduction of 13-valent pneumococcal conjugate vaccine (PCV-13) in July 2012, we performed molecular serotyping of 268 pneumococcal strains isolated from 221 children between 2012 and 2017. The median (interquartile range) age of the children included in this analysis was 6 (3,12) months. Fifty-nine percent of the children had received at least one dose of PCV-13 and 35% were fully vaccinated with PCV-13. While colonization by vaccine serotypes steadily declined following PCV-13 introduction, 25% of strains isolated more than 3 years after vaccine introduction were PCV-13 serotypes. We also observed an increase in colonization by non-vaccine serotypes 21 and 23B, which have been associated with invasive pneumococcal disease and antibiotic resistance in other settings.

Two promising live-attenuated RSV candidate vaccines, RSV/Delta NS2/Delta 1313/I1314L and RSV/276, were evaluated in 65 healthy children aged 6-24 months. Both products were restricted in replication; however, RSV/276 recipients had excess cough events. RSV/Delta NS2/Delta 1313/I1314L is a candidate for further clinical evaluation. Background This United States-based study compared 2 candidate vaccines: RSV/Delta NS2/Delta 1313/I1314L, attenuated by NS2 gene-deletion and temperature-sensitivity mutation in the polymerase gene; and RSV/276, attenuated by M2-2 deletion. Methods RSV-seronegative children aged 6-24 months received RSV/Delta NS2/Delta 1313/I1314L (10(6) plaque-forming units [PFU]), RSV/276 (10(5) PFU), or placebo intranasally. Participants were monitored for vaccine shedding, reactogenicity, and RSV serum antibodies, and followed over the subsequent RSV season. Results Enrollment occurred September 2017 to October 2019. During 28 days postinoculation, upper respiratory illness and/or fever occurred in 64% of RSV/Delta NS2/Delta 1313/I1314L, 84% of RSV/276, and 58% of placebo recipients. Symptoms were generally mild. Cough was more common in RSV/276 recipients than RSV/Delta NS2/Delta 1313/I1314L (48% vs 12%; P = .012) or placebo recipients (17%; P = .084). There were no lower respiratory illness or serious adverse events. Eighty-eight and 96% of RSV/Delta NS2/Delta 1313/I1314L and RSV/276 recipients were infected with vaccine (shed vaccine and/or had >= 4-fold rises in RSV antibodies). Serum RSV-neutralizing titers and anti-RSV F IgG titers increased >= 4-fold in 60% and 92% of RSV/Delta NS2/Delta 1313/I1314L and RSV/276 vaccinees, respectively. Exposure to community RSV during the subsequent winter was associated with strong anamnestic RSV-antibody responses. Conclusions Both vaccines had excellent infectivity and were well tolerated. RSV/276 induced an excess of mild cough. Both vaccines were immunogenic and primed for strong anamnestic responses.

BACKGROUND Recent studies have indicated that broadly neutralizing antibodies (bnAbs) in children may develop earlier after HIV infection compared to adults. METHODS We evaluated plasma from 212 ART-naïve, children living with HIV (1-3 years-old). Neutralization breadth and potency was assessed using a panel of 10 viruses and compared to adults with chronic HIV. The magnitude, epitope specificity and IgG subclass distribution of Env-specific antibodies were assessed using a binding antibody multiplex assay. RESULTS 1-year-old children demonstrated neutralization breadth comparable to chronically-infected adults, while 2 and 3-year olds exhibited significantly greater neutralization breadth (p=0.014). Similarly, binding antibody responses increased with age, with levels in 2 and 3 year-old children comparable to adults. Overall, there was no significant difference in antibody specificities or IgG subclass distribution between the pediatric and adult cohorts. Interestingly, the neutralization activity was mapped to a single epitope (CD4 binding site, V2 or V3 glycans) in only 5 of 38 pediatric broadly neutralizing samples, suggesting most children may develop a polyclonal neutralization response. CONCLUSIONS These results contribute to a growing body of evidence suggesting that initiating HIV immunization early in life may present advantages for the development of broadly neutralizing antibody responses.