Leukocyte Activation Patterns in Hospitalized Children: Comparing SARS-CoV-2, Bacterial Infections, and Inflammatory Pathologies.

In adults, monocytes and neutrophils play important roles in the hyper-inflammatory responses' characteristic of severe forms of SARS-CoV-2 infection. We assessed leukocyte activation in 55 children attending the emergency department for acute fever between March 2020 and September 2021. The following markers were analyzed by flow cytometry: CD169 and HLA-DR on monocytes, CD64 and CD16 on neutrophils, CD38 on lymphocytes TCD8. Fifteen of the children had SARS-CoV-2 infection, 15 had bacterial infections, 15 had inflammatory diseases. We observed overexpression of CD169 on monocytes and CD38 on lymphocytes T in all patients with a diagnosis of SARS-CoV-2, while overexpression of CD64 on neutrophils was observed with bacterial infections and inflammatory diseases. There was a decrease in the expression of HLA-DR on monocytes in the bacterial infection and inflammatory pathology groups. Leukocyte analysis identifies distinct activation patterns in children during SARS-CoV-2 infections, bacterial infections, and inflammatory diseases.

Optimised prevention of postnatal HIV transmission in Zambia and Burkina Faso (PROMISE-EPI): a phase 3, open-label, randomised controlled trial.

BACKGROUND: Transmission through breastfeeding accounts for more than half of the unacceptably high number of new paediatric HIV infections worldwide. We hypothesised that, in addition to maternal antiretroviral therapy (ART), extended postnatal prophylaxis with lamivudine, guided by point-of-care assays for maternal viral load, could reduce postnatal transmission. METHODS: We did a phase 3, open-label, randomised controlled trial at four health-care facilities in Zambia and four health-care facilities in Burkina Faso. Mothers with HIV and their breastfed infants without HIV attending the second visit of the Expanded Programme of Immunisation (EPI-2; infant age 6-8 weeks) were randomly assigned 1:1 to intervention or control groups. In the intervention group, maternal viral load was measured using Xpert HIV viral load assay at EPI-2 and at 6 months, with results provided immediately. Infants whose mothers had a viral load of 1000 copies per mL or higher were started on lamivudine syrup twice per day for 12 months or 1 month after breastfeeding discontinuation. The control group followed national guidelines for prevention of postnatal transmission of HIV. The primary outcome assessed by modified intention to treat was infant HIV infection at age 12 months, with HIV DNA point-of-care testing at 6 months and at 12 months. This trial is registered with ClinicalTrials.gov (NCT03870438). FINDINGS: Between Dec 12, 2019 and Sept 30, 2021, 34 054 mothers were screened for HIV. Among them, 1506 mothers with HIV and their infants without HIV, including 1342 mother and infant pairs from Zambia and 164 from Burkina Faso, were eligible and randomly assigned 1:1 to the intervention (n=753) or control group (n=753). At baseline, the median age of the mothers was 30·6 years (IQR 26·0-34·7), 1480 (98·4%) of 1504 were receiving ART, and 169 (11·5%) of 1466 had a viral load ≥1000 copies/mL. There was one case of HIV transmission in the intervention group and six in the control group, resulting in a transmission incidence of 0·19 per 100 person-years (95% CI 0·005-1·04) in the intervention group and 1·16 per 100 person-years (0·43-2·53) in the control group, which did not reach statistical significance (p=0·066). HIV-free survival and serious adverse events were similar in both groups. INTERPRETATION: Our intervention, initiated at EPI-2 and based on extended single-drug postnatal prophylaxis guided by point-of-care maternal viral load could be an important strategy for paediatric HIV elimination. FUNDING: The EDCTP2 programme with the support of the UK Department of Health & Social Care.

Using adult care visits to diagnose HIV infection in children, Burkina Faso.

Objective: To estimate the feasibility, positivity rate and cost of offering child testing for human immunodeficiency virus (HIV) to mothers living with HIV attending outpatient clinics in Burkina Faso. Methods: We conducted this implementation study in nine outpatient clinics between October 2021 and June 2022. We identified all women ≤ 45 years who were attending these clinics for their routine HIV care and who had at least one living child aged between 18 months and 5 years whose HIV status was not known. We offered these mothers an HIV test for their child at their next outpatient visit. We calculated intervention uptake, HIV positivity rate and costs. Findings: Of 799 eligible children, we tested 663 (83.0%) and identified 16 new HIV infections: 2.5% (95% confidence interval, CI: 1.5-4.1). Compared with HIV-negative children, significantly more HIV-infected children were breastfed beyond 12 months (P-value: 0.003) and they had not been tested before (P-value: 0.003). A significantly greater proportion of mothers of HIV-infected children were unaware of the availability of child testing at 18 months (P-value: < 0.001) and had more recently learnt their HIV status (P-value: 0.01) than mothers of HIV-negative children. The intervention cost 98.1 United States dollars for one child testing HIV-positive. Barriers to implementing this strategy included shortages of HIV tests, increased workload for health-care workers and difficulty accessing children not living with their mothers. Conclusion: Testing HIV-exposed children through their mothers in outpatient clinics is feasible and effective in a low HIV-prevalence setting such as Burkina Faso. Implementation of this strategy to detect undiagnosed HIV-infected children is recommended.

Evaluation of the prevention of mother-to-child transmission of HIV programs at the second immunization visit in Burkina Faso and Zambia.

OBJECTIVE: Our study aimed to assess the PMTCT indicators in Burkina Faso and Zambia using a patient-orientated innovative strategy based on the second visit in the Expanded Program on Immunization (EPI-2) visit at 6-8 weeks. DESIGN: This was a cross sectional study. METHODS: We assessed women attending EPI-2 at primary healthcare facilities in Burkina Faso and Zambia with their children about their exposure to PMTCT interventions. For women living with HIV (WLHIV), viral load was measured and their children were tested for HIV DNA using point of care devices. RESULTS: Overall, 25 093 were enrolled from Burkina Faso and 8961 women from Zambia. Almost, all women attended at least one antenatal care visit. Among those aware of their HIV-positive status, 95.8 and 99.2% were on antiretroviral therapy (ART) in Burkina Faso and Zambia, respectively. Among WLHIV on ART, 75 and 79.2% achieved a viral load suppression (viral load <1000 copies/ml) in Burkina Faso and Zambia, respectively. Infant postnatal prophylaxis was administered from birth until EPI-2 to 60.9 and 89.7% of HIV-exposed children in Burkina Faso and Zambia, respectively. In Burkina Faso, only 60 of 192 (31.3%) of HIV-exposed children were sampled at day 42 for early infant diagnosis (EID) and 3 (1.6%) received a result by EPI-2. In Zambia, these figures were 879 of 1465 (64.0%) and 9.9% (145/1465), respectively for HIV-exposed children sampled at birth. CONCLUSION: This evaluation strategy at EPI-2 visit could strengthen program monitoring and help identifying gaps to be addressed on the last mile towards elimination of MTCT of HIV.

SARS-CoV-2 nucleocapsid antigen in plasma of children hospitalized for COVID-19 or with incidental detection of SARS-CoV-2 infection.

In hospitalized children, SARS-CoV-2 infection can present as either a primary reason for admission (patients admitted for COVID-19) or an incidental finding during follow-up (patients admitted with COVID-19). We conducted a nested case-control study within a cohort of pediatric patients with confirmed SARS-CoV-2 infection, to investigate the concentration of plasma nucleocapsid antigen (N-Ag) in children admitted for COVID-19 or with COVID-19. While reverse transcriptase polymerase chain reaction Ct values in nasopharyngeal swab were similar between the two groups, children admitted for COVID-19 had a higher rate of detectable N-Ag (12/18 (60.7%) versus 6/18 (33.3%), p = 0.0455) and a higher concentration of N-Ag (medians: 19.51 g/mL vs. 1.08 pg/mL, p = 0.0105). In children hospitalized for COVID-19, the youngest had higher concentration of N-Ag (r = -0.74, p = 0.0004). We also observed a lower prevalence of detectable spike antibodies in children hospitalized for COVID-19 compared to those hospitalized for other medical reasons (3/15 [20%] vs. 13/16 [81.25%], respectively, p = < 0.0011), but similar rates of IgG nucleocapsid antibodies (5/14 [35.7%] vs. 6/17 [35.3%], respectively, p = 0.99). Our findings indicate that N-Ag is associated with COVID-19-related hospitalizations in pediatric patients, and less frequently detected in children tested positive for SARS-CoV-2 but hospitalized for another medical reason. Further studies are needed to confirm the value of N-Ag in identifying COVID-19 disease infections in which SARS-CoV-2 is the main pathogen responsible for symptoms.

Leptospirosis Cases among Outpatients with Non-Malaria Fever Attending Primary Care Clinics during the Rainy Season in Bobo Dioulasso, Burkina Faso.

Leptospirosis is presumably an important cause of non-malarial fever in West Africa. In this study, outpatients consulting in primary care clinics during the rainy season were tested for leptospirosis, and clinical characteristics associated with leptospirosis cases were explored. Patients with fever ≥ 39°C were recruited in nine primary health care centers in Bobo Dioulasso (Burkina Faso). Diagnosis of malaria was ruled out using a rapid diagnostic test (RDT; SD Bioline Malaria®). Leptospirosis cases were defined as patients who tested positive for Leptospira IgM (Leptocheck-WB RDT and Leptospira IgM ELISA assay, Panbio) or DNA in plasma (LipL32 polymerase chain reaction [PCR]). Among 350 patients, 202 tested positive for malaria and were excluded, and 148 met the eligibility criteria and were included. Among these, 26 subjects were considered to be leptospirosis cases: 23 tested positive for Leptospira IgM (15.5%) and three tested positive by PCR (2.2%). Headaches, abdominal symptoms, and myalgia were frequently reported without any difference between leptospirosis cases and negative cases. Cough was more frequently observed among subjects testing positive for leptospirosis (P = 0.02). Water exposure, presence of a skin injury, and walking barefoot were associated with a Leptospira-positive test. All leptospirosis cases recovered without sequelae. A significant portion of outpatients with non-malarial febrile illness during the rainy season in Burkina Faso had epidemiological factors associated with leptospirosis and tested positive for Leptospira. The favorable outcome of leptospirosis cases was reassuring; this could be due in particular to the young age of the patients.

Mosquito (Diptera: Culicidae) populations in contrasting areas of the western regions of Burkina Faso: species diversity, abundance and their implications for pathogen transmission.

BACKGROUND: Mosquitoes (Diptera: Culicidae) can have a significant negative impact on human health. The urbanization of natural environments and their conversion for agricultural use, as well as human population growth, may affect mosquito populations and increase the risk of emerging or re-emerging mosquito-borne diseases. We report on the variety and number of adult mosquitoes found in four environments with varying degrees of human impact (rural, urban, rice fields, and forest) located in a savannah zone of West Africa. METHODS: Mosquitoes were collected from two regions (Hauts-Bassins and Sud-Ouest) of Burkina Faso during five periods between August 2019 and June 2021. Sampling sites were grouped according to environment. Mosquitoes were collected using BG-Sentinel traps and double net traps, and Prokopack Aspirators. Statistical analyses were performed using R software version 4.1.2. Logistic regression, using generalised mixed linear models, was used to test the effect of environment on mosquito abundance and diversity. Alpha diversity analysis was also performed, using the vegan package. RESULTS: A total of 10,625 adult mosquitoes were collected, belonging to 33 species and five genera: Culex, Aedes, Anopheles, Mansonia, and Ficalbia. The most dominant species were Culex quinquefasciatus, Anopheles gambiae sensu lato and Aedes aegypti. Alpha diversity was similar in the two regions. Habitat had a significant effect on mosquito species richness, the Shannon index and the Simpson index. The rural environment had the highest species richness (n = 28) followed by the forest environment (n = 24). The highest number of mosquitoes (4977/10,625) was collected in the urban environment. CONCLUSIONS: The species composition of the mosquito populations depended on the type of environment, with fewer species in environments with a high human impact such as urban areas and rice fields. Due to the diversity and abundance of the mosquito vectors, the human populations of all of the environments examined are considered to be at potential risk of mosquito-borne diseases.

HCV RNA Quantification by a Domestic Commercial Assay: A Case Study among People Who Inject Drugs in Vietnam.

The desired performance of nucleic acid testing (NAT) may vary if used for disease diagnosis or for the evaluation of the therapeutic efficacy of a treatment, although in most cases, the same assay is used. However, these tests may not be affordable in many situations including in low/middle income countries that in response have developed domestic assays. Given the example of HCV NAT among people who inject drugs in Vietnam, we aimed at evaluating a domestic assay versus an FDA- and CE-approved assay. This cross-evaluation revealed that (i) the domestic assay had a poorer sensitivity with a threshold of detection above 104 IU/mL, and (ii) the FDA-approved assay had a percentage of false negative results close to 1%. Together, in the present study, the domestic assay had a performance compatible with diagnosis purposes (given that this population was 70% HCV seropositive) but not compatible with HCV treatment monitoring (given that treatment failures are rare and the observed viremia frequently below the threshold of detection). This study highlights the need for a proper evaluation of HCV RNA domestic assays in order to efficiently contribute to the WHO HCV elimination target by 2030.

Facilitators and barriers to infant post-natal HIV prophylaxis, a qualitative sub-study of the PROMISE-EPI trial in Lusaka, Zambia.

Background: Infant post-natal prophylaxis (PNP) is used to prevent HIV transmission through breastfeeding. The WHO edited recommendations but so far there is no consensus on the duration of prophylaxis and the type of drug used depends on national guidelines. In Zambia, the national recommendations include a three-drug prophylaxis, composed of a dispersible combined tablet of zidovudine (AZT) and lamivudine (3TC) and an oral suspension of nevirapine (NVP) for 12 weeks or until the mother's viral load is <1,000 cp/mL. The PROMISE-EPI study, modified the PNP regimen to lamivudine only, initiated at 6 weeks and continued until 12 months to all HIV exposed uninfected infants of virally unsuppressed mothers. Our aim in this analysis was to identify barriers and facilitators to this extended PNP, the keystone toward an effective prevention. Methods: Individual interviews and focus group discussion (FGD) were conducted with PROMISE-EPI participants who had received prophylaxis for their children from the national program up to 6 weeks and then lamivudine oral solution in PROMISE-EPI study. Health care providers and PROMISE-EPI staff were also interviewed. Sessions were recorded, transcribed verbatim and translated from local languages into English. An initial code-book was designed and then adapted on the basis of the emerging themes, to allow a descriptive thematic analysis. Results: More barriers to PNP adherence were identified with triple drug prophylaxis than with lamivudine. These barriers were related to the formulation and bitter taste of AZT/3TC tablets. The ready to use formulation and sweet taste of lamivudine syrup were appreciated by mothers. Extended PNP proposed in the PROMISE-EPI study was globally well accepted and strategies were found to increase adherence. Adherence to lamivudine appeared to be better than the mothers' adherence to their own antiretroviral therapy. Conclusion: Accompanying mothers living with HIV and giving them the choice of the PNP to prevent transmission via breastfeeding (type of PNP regimen and extended PNP in non-adherent mothers), may be one of the keys to reducing the burden of pediatric HIV acquisition in low and middle income countries.

Quantification of Female Chimeric Cells in the Tonsils of Male Children and Their Determinants.

The factors influencing mother-to-child cell trafficking and persistence over children's lives have yet to be established. The quantification of maternal microchimerism was previously reported through HLA-based approaches, which introduced bias regarding the tolerogenic environment. We aimed to identify cells of maternal origin irrespective of the HLA repertoire and to ascertain the determinants of microchimeric cells. This case-control study enrolled 40 male infants attending pediatric surgery from January 2022 to October 2022. Female cells were quantified in infants' tonsil tissue by using cytogenetic fluorescent in situ hybridization (FISH) coupled with optimized automated microscopy. Out of the 40 infants, half (47.4%) had been breastfed for more than one month, a quarter for less a month, and 10 children (26.3%) were never breastfed. XX cells were observed in male tonsils in two-thirds of participants at a median density of 5 cells per 100,000 cells. In univariate analyses, child age was negatively associated with a high female cell density. In exploratory multivariate analyses, previous breastfeeding is a likely determinant of the persistence of these cells in the host, as well as the rank among siblings. Part of the benefit of breastmilk for child health may therefore be driven by breastfeeding-related microchimerism.

Differential effects of Usutu and West Nile viruses on neuroinflammation, immune cell recruitment and blood-brain barrier integrity.

Usutu (USUV) and West Nile (WNV) viruses are two closely related Flavivirus belonging to Japanese encephalitis virus serogroup. Evidence of increased circulation of these two arboviruses now exist in Europe. Neurological disorders are reported in humans mainly for WNV, despite the fact that the interaction and effects of viral infections on the neurovasculature are poorly described, notably for USUV. Using a human in vitro blood-brain barrier (BBB) and a mouse model, this study characterizes and compares the cerebral endothelial cell permissiveness, innate immunity and inflammatory responses and immune cell recruitment during infection by USUV and WNV. Both viruses are able to infect and cross the human BBB but with different consequences. We observed that WNV infects BBB cells resulting in significant endothelium impairment, potent neuroinflammation and immune cell recruitment, in agreement with previous studies. USUV, despite being able to infect BBB cells with higher replication rate than WNV, does not strongly affect endothelium integrity. Importantly, USUV also induces neuroinflammation, immune cell recruitment such as T lymphocytes, monocytes and dendritic cells (DCs) and was able to infect dendritic cells (DCs) more efficiently compared to WNV, with greater propensity for BBB recruitment. DCs may have differential roles for neuroinvasion of the two related viruses.

Prevention of mother-to-child transmission of HIV at the second immunization visit: a cross-sectional study, Burkina Faso.

Objective: To evaluate the performance of the cascade of activities for prevention of mother-to-child transmission (PMTCT) of human immunodeficiency virus (HIV) at the second immunization visit in Burkina Faso. Methods: In a cross-sectional study, we recruited mothers attending the second immunization visit for their infant in 20 health centres of Bobo-Dioulasso city, Burkina Faso over 12 months (2019-2020). We administered a short questionnaire to 14 176 mothers and performed HIV serological tests on mothers who had not been tested in the last 3 months. All mothers were asked about their attendance for antenatal care and HIV rapid testing. HIV-infected mothers were also asked about the timing of their HIV diagnosis, antiretroviral therapy, pre-exposure prophylaxis initiation at birth and infant diagnosis of HIV. Findings: Of 14 136 respondents, 13 738 (97.2%) had at least one HIV serological test in their lifetime. Of 13 078 mothers who were never tested or were HIV-negative, 12 454 (95.2%) were tested during or after their last pregnancy. Among HIV-infected mothers already aware of their status, 110/111 (99.1%) women were on antiretroviral therapy. Among HIV-exposed infants, 84/101 (83.2%) babies received 6 weeks of antiretroviral prophylaxis at birth and 58/110 (52.7%) had a blood sample collected for early infant diagnosis. Only two mothers received their child's test results at the time of the second immunization visit. Four mothers were newly diagnosed as HIV-positive during the study. Conclusion: Collecting data at the second immunization visit, a visit rarely missed by mothers, could be useful for identifying gaps in the PMTCT cascade in settings where mothers are difficult to reach, such as in low-income countries with intermediate or low HIV prevalence.

Evaluation of post-infectious inflammatory reactions in a retrospective study of 3 common invasive bacterial infections in pediatrics.

Infectious diseases can result in unanticipated post-infectious inflammatory reactions (PIIR). Our aim was to explore PIIR in 3 frequent pediatric bacterial invasive infections in France by a retrospective monocentric study. We included children hospitalized between 2003 and 2012 for Streptococcus pneumoniae (SP), Neisseria meningitidis (NM), or Streptococcus pyogenes invasive infections. The PIIR had to have occurred between 3 and 15 days without fever despite an individually tailored antibiotic therapy. A descriptive analysis was carried out to determine PIIR risk factors. We included 189 patients, of whom 72, 79, and 38 exhibited invasive infections caused by S pyogenes, SP, and NM, respectively. The mean age was 44 months. PIIR were observed in 39 cases, occurring after a median of 8 days (5-12), with a median duration of 3 days (2-6). Fever, arthritis, and pleural effusion were observed in 87%, 28.2%, and 25.6%, respectively. In multivariate analysis, PIIR were associated with pleuropneumonia, hospitalization in an intensive care unit (ICU), and elevated C-reactive protein (CRP). PIIR were observed in 20% of children after SP, NM, or S pyogenes invasives infections. Their occurrence was associated with the initial severity but not the etiological microorganism. Further studies are warranted to confirm these findings.

Long-Term Persistence of Mitochondrial DNA Instability among HCV-Cured People Who Inject Drugs.

People who inject drugs (PWID) are a population exposed to many genotoxicants and with a high prevalence of HCV infection. Direct-acting antiviral (DAA) regimens are now widely used to treat chronic HCV infection. Although side effects to treatment are currently rare, the long-term effects such as suspicions of de novo hepatocellular carcinoma (HCC) occurrence or HCC recurrence and cardiac defects are still up for debate. Given the structure of DAAs, the molecules have a potential mitochondrial DNA (mtDNA) genotoxicity. We have previously reported acute mtDNA toxicity of three DAA regimens among PWID with a strong impact on the rate of mtDNA deletion, less on the quantity of mtDNA copy per cell at sustained viral response at 12 weeks (SVR12). Herein, we report the mtDNA parameters nine months after drug discontinuation. We observed that the percentage of the deleted mtDNA genome increased over time. No exposure to any other genotoxicants during this period was associated with a high deletion percentage, suggesting that the replicative advantage of the deleted molecules outweighed their elimination processes. Such observation calls for longer-term follow-up and may contribute to the molecular basis of subclinical side effects of DAA treatments.