Performance of VIDAS® Diagnostic Tests for the Automated Detection of Dengue Virus NS1 Antigen and of Anti-Dengue Virus IgM and IgG Antibodies: A Multicentre, International Study.

Dengue is a serious mosquito-transmitted disease caused by the dengue virus (DENV). Rapid and reliable diagnosis of DENV infection is urgently needed in dengue-endemic regions. We describe here the performance evaluation of the CE-marked VIDAS® dengue immunoassays developed for the automated detection of DENV NS1 antigen and anti-DENV IgM and IgG antibodies. A multicenter concordance study was conducted in 1296 patients from dengue-endemic regions in Asia, Latin America, and Africa. VIDAS® dengue results were compared to those of competitor enzyme-linked immunosorbent assays (ELISA). The VIDAS® dengue assays showed high precision (CV ≤ 10.7%) and limited cross-reactivity (≤15.4%) with other infections. VIDAS® DENGUE NS1 Ag showed high positive and negative percent agreement (92.8% PPA and 91.7% NPA) in acute patients within 0-5 days of symptom onset. VIDAS® Anti-DENGUE IgM and IgG showed a moderate-to-high concordance with ELISA (74.8% to 90.6%) in post-acute and recovery patients. PPA was further improved in combined VIDAS® NS1/IgM (96.4% in 0-5 days acute patients) and IgM/IgG (91.9% in post-acute patients) tests. Altogether, the VIDAS® dengue NS1, IgM, and IgG assays performed well, either alone or in combination, and should be suitable for the accurate diagnosis of DENV infection in dengue-endemic regions.

Coinfections with SARS-CoV-2 variants and influenza virus during the 2019 Coronavirus disease pandemic in Burkina Faso: A surveillance study.

Background and Aim: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) particularly the variants of concern coinfections with influenza is a public health concern in Africa. We aimed to characterize the SARS-CoV-2 variants and determine the rate of coinfections with influenza in Burkina Faso. Methods: COVID-19 surveillance study was conducted between August 2021 and January 2022 using reverse transcription polymerase chain reaction (RT-PCR). Positive specimens were further screened for SARS-CoV-2 variants using the multiple variants real-time PCR kits. In addition, influenza virus strains were detected by RT-PCR in SARS-CoV-2 positive specimens using the CDC primers, probes, and protocols. Results: Of 324 specimens assessed, the Omicron and Delta variants of SARS-CoV-2 were the most prevalent with 27.2% [95% confident interval (CI): 22.5-32.4] and 22.2% [95% CI: 17.9-27.2], respectively. The Beta and Gamma variants were detected in 4.3% [95% CI: 2.4-7.1] and 0.3% [95% CI: 0.0-1.7], respectively. Coinfections of Omicron and Beta variants were reported in 21.3% [95% CI: 17.0-26.2], Omicron and Delta variants in 1.2% [95% CI: 0.3-3.1] of specimens, and the Omicron-Gamma variants' coinfections in 0.6% [95% CI: 0.1-2.2]. One COVID-19 specimen with an undetected SARS-CoV-2 variant was also tested positive for the seasonal influenza A (H3N2) virus. No cases of pandemic influenza A (H1N1)pdm09, seasonal A/H1N1, and influenza B were detected. Conclusions: The current World Health Organization SARS-CoV-2 variants of concern were prevalent and their coinfections with influenza were uncommon. Continuous surveillance of both pathogens is, however, needed because of their public health implications.

Magnitude and associated factors of latent tuberculosis infection due to Mycobacterium tuberculosis complex among high-risk groups in urban Bobo-Dioulasso, Burkina Faso.

Objectives: To determine the prevalence and risk factors for latent tuberculosis infection (LTBI) among three high-risk groups - household contacts of TB index cases, healthcare workers and slaughterhouse workers - in Bobo-Dioulasso, Burkina Faso. Methods: Participants were recruited to this cross-sectional study from March to July 2020 after giving informed consent. Sociodemographic, clinical and biological data were collected using a structured questionnaire. The QuantiFERON-TB Gold Plus test (QFT-Plus) and the tuberculin skin test (TST) were used for detection of LTBI. Bivariate and multivariate logistic regression analyses were performed to identify risk factors for LTBI. Results: The prevalence of LTBI among 101 participants (age range 15-68 years) was 67.33% [95% confidence interval (CI) 57.27-76.33] and 84.16% (95% CI 75.55-90.66) based on QFT-Plus and TST results, respectively. Compared with healthcare workers and household contacts of TB index cases, the prevalence of LTBI among slaughterhouse workers was significantly higher for both QTF-Plus (96.8%; P<0.001) and TST (100%; P=0.003). Working in a slaughterhouse [adjusted odds ratio (AOR) 1.095, 95% CI 1.00-2.036], smoking (AOR 4.214, 95% CI 1.051-16.899), ≥15 years of exposure (AOR 5.617, 95% CI 1.202-32.198), having an animal at home (AOR 2.735, 95% CI 1.102-6.789) and protozoal infection (AOR 2.591, 95% CI 1.034-6.491) were significantly associated with LTBI on the QFT-Plus assay. Conclusion: The prevalence of LTBI was high in all three groups, particularly slaughterhouse workers. The risk factors identified could form the basis of targeted intervention.

Serological and molecular detection of Leishmania species in dog peripheral blood from Bobo-Dioulasso city, a confirmation of canine leishmaniasis enzootic area for Burkina Faso.

Canine leishmaniasis is increasingly reported worldwide and represent a threat to both animal and human health. In a previous pilot study conducted in Bobo-Dioulasso, the second town of Burkina Faso, we reported five cases of canine leishmaniasis. With the perspective of a One Health action plan, and in the context of increasing urbanization, this study aimed to provide new information on Leishmania spp in dogs in this city. A cross-sectional survey was carried out from May to August 2018 in six districts of the city in order to record clinical and biological data from domestic dogs randomly selected per district. Blood samples were collected into EDTA tubes (4-5 mL), treated and stored at -20 °C until further analyses. The infection status of the dogs was performed by serological tests using plasma, and real time-PCR (RT-PCR) to detect Leishmania parasites using buffy coats. Nested PCR was used for typing the Leishmania species in dogs which were found to be RT-PCR positive. A total of 147 dogs were examined clinically and sampled for blood collection, including 53.7% females and 46.3% of males with a median age of 3 years. The seroincidence of Leishmania parasites within this dog population was 4.76% (95% CI:2.26-9.72). The incidence of Leishmania was 10.88% (95% CI: 6.73-17.11) by RT-PCR which was significantly more sensitive (p = 0,047) and a fair concordance was observed between both tests (Kappa = 0.39, p < 0.001). The characterization of Leishmania species revealed that L. major was circulating in this domestic dog population. Our results confirmed the persistence of zoonotic circulation of Leishmania parasites such as L. major currently in Bobo-Dioulasso city and highlight the need for targeted interventions in order to control transmission of leishmaniasis in this region.

Pharmacokinetic study of two different rifabutin doses co-administered with lopinavir/ritonavir in African HIV and tuberculosis co-infected adult patients.

BACKGROUND: This study aimed to assess the pharmacokinetic profile of 150 mg rifabutin (RBT) taken every other day (every 48 h) versus 300 mg RBT taken every other day (E.O.D), both in combination with lopinavir/ritonavir (LPV/r), in adult patients with human immunodeficiency virus (HIV) and tuberculosis (TB) co-infection. METHODS: This is a two-arm, open-label, pharmacokinetic, randomised study conducted in Burkina Faso between May 2013 and December 2015. Enrolled patients were randomised to receive either 150 mg RBT EOD (arm A, 9 subjects) or 300 mg RBT EOD (arm B, 7 subjects), both associated with LPV/r taken twice daily. RBT plasma concentrations were evaluated after 2 weeks of combined HIV and TB treatment. Samples were collected just before drug ingestion and at 1, 2, 3, 4, 6, 8, and 12 h after drug ingestion to measure plasma drug concentration using an HPLC-MS/MS assay. RESULTS: The Cmax and AUC0-12h medians in arm A (Cmax = 296 ng/mL, IQR: 205-45; AUC0-12h = 2528 ng.h/mL, IQR: 1684-2735) were lower than those in arm B (Cmax = 600 ng/mL, IQR: 403-717; AUC0-12h = 4042.5 ng.h/mL, IQR: 3469-5761), with a statistically significant difference in AUC0-12h (p = 0.044) but not in Cmax (p = 0.313). No significant differences were observed in Tmax (3 h versus 4 h). Five patients had a Cmax below the plasma therapeutic limit (< 300 ng/mL) in the 150 mg RBT arm, while the Cmax was above this threshold for all patients in the 300 mg RBT arm. Additionally, at 48 h after drug ingestion, all patients had a mycobacterial minimum inhibitory concentration (MIC) above the limit (> 64 ng/mL) in the 300 mg RBT arm, while 4/9 patients had such values in the 150 mg RBT arm. CONCLUSION: This study confirmed that the 150 mg dose of rifabutin ingested EOD in combination with LPV/r is inadequate and could lead to selection of rifamycin-resistant mycobacteria. TRIAL REGISTRATION: PACTR201310000629390, 28th October 2013.

Pharmacokinetics of plasma lopinavir and ritonavir in tuberculosis-HIV co-infected African adult patients also receiving rifabutin 150 or 300 mg three times per week.

BACKGROUND: To evaluate the pharmacokinetic of plasma lopinavir (LPV) and ritonavir (RTV) when co-administered with three times weekly (TPW) rifabutin (RBT) at a dose of either 150 or 300 mg in African tuberculosis (TB) and HIV co-infected adult patients. METHODS: This is a pharmacokinetic study conducted in Ouagadougou among patients treated with a standard dosage of LPV/RTV 400/100 mg twice daily and RBT 150 mg TPW (arm A = 9 patients) or rifabutin 300 mg TPW (arm B = 7 patients) based regimens. Patients were recruited from the Bogodogo and Kossodo district hospitals in Ouagadougou from May 2013 to December 2015. Study inclusion criteria were that the patients were between 18 and 60 years of age, HIV-1 infected with pulmonary tuberculosis confirmed or suspected. Subsequent blood samples for pharmacokinetic monitoring were collected at 1, 2, 3, 4, 6, 8 and 12 h after combined drug ingestion for plasma drug monitoring using HPLC/MS assays. RESULTS: The medians LPV Cmax and Tmax were respectively, 20 µg/mL and 4 h for the RBT 150 mg group (arm A) and 7.7 µg/mL and 3 h for the RBT 300 mg group (arm B). The AUC0-12 of LPV was 111.8 µg h/mL in patients belonging to arm A versus 69.9 µg/mL for those in arm B (p = 0.313). The C0 of LPV was lower than 4 µg/mL in three patients receiving RBT 300 mg. Of note, the RTV plasma concentrations were nearly halved among patients on RBT 300 mg compared to those on lower RBT doses. The AUC0-12 of RTV in arm A was 12.7 µg h/mL versus 6.6 µg h/ml in arm B (p = 0.313). CONCLUSION: In our study, the pharmacokinetic of LPV and RTV was found to be highly variable when coadministrated with RBT 150 mg or 300 mg three times per week. There is a need for specific large study to verify clinical and virological effects of this variation, especially when coadministrated with RBT of 300 mg TPW, and to prevent viral resistance in response to under-dosing of LPV. Trial registration PACTR201310000629390. Registered 28 October 2013, http://www.pactr.org/.

Human immunodeficiency virus type 1 drug resistance in a subset of mothers and their infants receiving antiretroviral treatment in Ouagadougou, Burkina Faso.

The emergence of HIV-1 drug resistance (HIVDR) is a public health problem that affects women and children. Local data of HIVDR is critical to improving their care and treatment. So, we investigated HIVDR in mothers and infants receiving antiretroviral therapy (ART) at Saint Camille Hospital of Ouagadougou, Burkina Faso. This study included 50 mothers and 50 infants on ART. CD4 and HIV-1 viral load were determined using FACSCount and Abbott m2000rt respectively. HIVDR was determined in patients with virologic failure using ViroSeq HIV-1 Genotyping System kit on the 3130 Genetic Analyzer. The median age was 37.28 years in mothers and 1.58 year in infants. Sequencing of samples showed subtypes CRF02_AG (55.56%), CRF06_cpx (33.33%) and G (11.11%). M184V was the most frequent and was associated with highlevel resistance to 3TC, FTC, and ABC. Other mutations such as T215F/Y, D67N/E, K70R, and K219Q were associated with intermediate resistance to TDF, AZT, and 3TC. No mutation to LPV/r was detected among mothers and infants. The findings of HIVDR in some mothers and infants suggested the change of treatment for these persons.

Dengue Fever in Burkina Faso, 2016.

We report 1,327 probable cases of dengue in Burkina Faso in 2016. Of 35 serum samples tested by a trioplex test, 19 were confirmed dengue virus (DENV)‒positive: 11 DENV-2, 6 DENV-3, 2 nontypeable, and 1 DENV-2/DENV-3 co-infection. Molecular testing should be conducted to correctly identify causative agents in this complex infectious disease landscape.

Human immunodeficiency virus type 1 drug resistance in a subset of mothers and their infants receiving antiretroviral treatment in Ouagadougou, Burkina Faso

The emergence of HIV-1 drug resistance (HIVDR) is a public health problem that affects women and children. Local data of HIVDR is critical to improving their care and treatment. So, we investigated HIVDR in mothers and infants receiving antiretroviral therapy (ART) at Saint Camille Hospital of Ouagadougou, Burkina Faso. This study included 50 mothers and 50 infants on ART. CD4 and HIV-1 viral load were determined using FACSCount and Abbott m2000rt respectively. HIVDR was determined in patients with virologic failure using ViroSeq HIV-1 Genotyping System kit on the 3130 Genetic Analyzer. The median age was 37.28 years in mothers and 1.58 year in infants. Sequencing of samples showed subtypes CRF02_AG (55.56%), CRF06_cpx (33.33%) and G (11.11%). M184V was the most frequent and was associated with highlevel resistance to 3TC, FTC, and ABC. Other mutations such as T215F/Y, D67N/E, K70R, and K219Q were associated with intermediate resistance to TDF, AZT, and 3TC. No mutation to LPV/r was detected among mothers and infants. The findings of HIVDR in some mothers and infants suggested the change of treatment for these persons

School Children's Intestinal Parasite and Nutritional Status One Year after Complementary School Garden, Nutrition, Water, Sanitation, and Hygiene Interventions in Burkina Faso.

The potential health benefits of combined agricultural, nutrition, water, sanitation, and hygiene (WASH) interventions are poorly understood. We aimed to determine whether complementary school garden, nutrition, and WASH interventions reduce intestinal parasites and improve school children's nutritional status in two regions of Burkina Faso. A cluster-randomized controlled trial was conducted in the Plateau Central and Center-Ouest regions of Burkina Faso. A total of 360 randomly selected children, aged 8-15 years, had complete baseline and end-line survey data. Mixed regression models were used to assess the impact of the interventions, controlling for baseline characteristics. The prevalence of intestinal parasitic infections decreased both in intervention and control schools, but the decrease was significantly higher in the intervention schools related to the control schools (odds ratio [OR] of the intervention effect = 0.2, 95% confidence interval [CI] = 0.1-0.5). Indices of undernutrition did not decrease at end-line in intervention schools. Safe handwashing practices before eating and the use of latrines at schools were significantly higher in the intervention schools than in the control schools at end-line (OR = 6.9, 95% CI = 1.4-34.4, and OR = 14.9, 95% CI = 1.4-153.9, respectively). Parameters of water quality remained unchanged. A combination of agricultural, nutritional, and WASH-related interventions embedded in the social-ecological systems and delivered through the school platform improved several child health outcomes, including intestinal parasitic infections and some WASH-related behaviors. Sustained interventions with stronger household and community-based components are, however, needed to improve school children's health in the long-term.

Prevalence and risk factors of undernutrition among schoolchildren in the Plateau Central and Centre-Ouest regions of Burkina Faso.

BACKGROUND: Multiple factors determine children's nutritional status, including energy and nutrient intake, recurrent infectious diseases, access (or lack thereof) to clean water and improved sanitation, and hygiene practices, among others. The "Vegetables go to School: improving nutrition through agricultural diversification" (VgtS) project implements an integrated school garden programme in five countries, including Burkina Faso. The aim of this study was to determine the prevalence of undernutrition and its risk factors among schoolchildren in Burkina Faso before the start of the project. METHODS: In February 2015, a cross-sectional survey was carried out among 455 randomly selected children, aged 8-14 years, in eight schools in the Plateau Central and Centre-Ouest regions of Burkina Faso. Nutritional status was determined by anthropometric assessment. Helminth and intestinal protozoa infections were assessed using the Kato-Katz and a formalin-ether concentration method. A urine filtration technique was used to identify Schistosoma haematobium eggs. Prevalence of anaemia was determined by measuring haemoglobin levels in finger-prick blood samples. Questionnaires were administered to children to determine their knowledge of nutrition and health and their related attitudes and practices (KAP). Questionnaires were also administered to the children's caregivers to identify basic household socio-demographic and economic characteristics, and water, sanitation and hygiene (WASH) conditions. To determine the factors associated with schoolchildren's nutritional status, mixed logistic regression models were used. Differences and associations were considered statistically significant if P-values were below 0.05. RESULTS: Complete datasets were available for 385 children. The prevalence of undernutrition, stunting and thinness were 35.1%, 29.4% and 11.2%, respectively. The multivariable analysis revealed that undernutrition was associated with older age (i.e. 12-14 years compared to <12 years; adjusted odds ratio (aOR) = 3.45, 95% confidence interval (CI) 2.12-5.62, P < 0.001), multiple pathogenic parasitic infections (aOR = 1.87, 95% CI 1.02-3.43, P = 0.044) and with moderate and severe anaemia in children (aOR = 2.52, 95% CI 1.25-5.08, P = 0.010). CONCLUSIONS: We found high prevalence of undernutrition among the children surveyed in the two study regions of Burkina Faso. We further observed that undernutrition, anaemia and parasitic infections were strongly associated. In view of these findings, concerted efforts are needed to address undernutrition and associated risk factors among school-aged children. As part of the VgtS project, WASH, health education and nutritional interventions will be implemented with the goal to improve children's health. TRIAL REGISTRATION: ISRCTN17968589 (date assigned: 17 July 2015).

Prevalence of intestinal parasitic infections and associated risk factors among schoolchildren in the Plateau Central and Centre-Ouest regions of Burkina Faso.

BACKGROUND: Unsafe drinking water, unimproved sanitation and lack of hygiene pose health risks, particularly to children in low- and middle-income countries. This study aimed to assess the prevalence and risk factors of intestinal parasitic infections in school-aged children in two regions of Burkina Faso. METHODS: A cross-sectional survey was carried out in February 2015 with 385 children aged 8-14 years from eight randomly selected schools in the Plateau Central and Centre-Ouest regions of Burkina Faso. Stool samples were subjected to the Kato-Katz and a formalin-ether concentration method for the diagnosis of helminths and intestinal protozoa infections. Urine samples were examined with a urine filtration technique for Schistosoma haematobium eggs. Water samples from community sources (n = 37), children's households (n = 95) and children's drinking water cups (n = 113) were analysed for contamination with coliform bacteria and faecal streptococci. Data on individual and family-level risk factors were obtained using a questionnaire. Mixed logistic regression models were employed to determine factors associated with intestinal parasitic infections in schoolchildren. RESULTS: Intestinal parasitic infections were highly prevalent; 84.7 % of the children harboured intestinal protozoa, while helminth infections were diagnosed in 10.7 % of the children. We found significantly lower odds of pathogenic intestinal protozoa infection (Entamoeba histolytica/E. dispar and Giardia intestinalis) among children from the Plateau Central, compared to the Centre-Ouest region (P < 0.001). Children from households with "freely roaming domestic animals" (P = 0.008), particularly dogs (P = 0.016) showed higher odds of G. intestinalis, and children reporting exposure to freshwater sources through domestic chores had higher odds of S. haematobium infection compared to children without this water contact activity (P = 0.035). Water quality, household drinking water source and storage did not emerge as significant risk factors for intestinal parasitic infections in children. CONCLUSIONS: Intestinal protozoa but not helminths were highly prevalent among schoolchildren in randomly selected schools in two regions of Burkina Faso. Our findings call for specific public health measures tailored to school-aged children and rural communities in this part of Burkina Faso. It will be interesting to assess the effect of water, sanitation and hygiene interventions on the transmission of intestinal parasitic infections. TRIAL REGISTRATION: ISRCTN17968589 (date assigned: 17 July 2015).

Complementary school garden, nutrition, water, sanitation and hygiene interventions to improve children's nutrition and health status in Burkina Faso and Nepal: a study protocol.

BACKGROUND: Malnutrition and intestinal parasitic infections are common among children in Burkina Faso and Nepal. However, specific health-related data in school-aged children in these two countries are scarce. In the frame of a larger multi-stakeholder project entitled "Vegetables go to School: Improving Nutrition through Agricultural Diversification" (VgtS), a study has been designed with the objectives to: (i) describe schoolchildren's health status in Burkina Faso and Nepal; and to (ii) provide an evidence-base for programme decisions on the relevance of complementary school garden, nutrition, water, sanitation and hygiene (WASH) interventions. METHODS/DESIGN: The studies will be conducted in the Centre Ouest and the Plateau Central regions of Burkina Faso and the Dolakha and Ramechhap districts of Nepal. Data will be collected and combined at the level of schools, children and their households. A range of indicators will be used to examine nutritional status, intestinal parasitic infections and WASH conditions in 24 schools among 1144 children aged 8-14 years at baseline and a 1-year follow-up. The studies are designed as cluster randomised trials and the schools will be assigned to two core study arms: (i) the 'complementary school garden, nutrition and WASH intervention' arm; and the (ii) 'control' arm with no interventions. Children will be subjected to parasitological examinations using stool and urine samples and to quality-controlled anthropometric and haemoglobin measurements. Drinking water will be assessed for contamination with coliform bacteria and faecal streptococci. A questionnaire survey on nutritional and health knowledge, attitudes and practices (KAP) will be administered to children and their caregivers, also assessing socioeconomic, food-security and WASH conditions at household level. Focus group and key-informant interviews on children's nutrition and hygiene perceptions and behaviours will be conducted with their caregivers and school personnel. DISCUSSION: The studies will contribute to fill a data gap on school-aged children in Burkina Faso and Nepal. The data collected will also serve to inform the design of school-based interventions and will contribute to deepen the understanding of potential effects of these interventions to improve schoolchildren's health in resource-constrained settings. Key findings will be used to provide guidance for the implementation of health policies at the school level in Burkina Faso and Nepal. TRIAL REGISTRATION: ISRCTN30840 (date assigned: 17 July 2015).

Evaluation of the diagnostic performance and operational characteristics of four rapid immunochromatographic syphilis tests in Burkina Faso.

BACKGROUND AND OBJECTIVE: Little information is available on the rapid diagnostic testing for syphilis in Burkina Faso. The objectives of the study were (i) to assess the sensitivity and specificity of four on site rapid tests in comparison with Treponema pallidum haemagglutination assay (TPHA) as a gold standard and (ii) to evaluate the operational characteristics of those tests among health workers in a maternity unit. METHODS: Four rapid syphilis tests commercially available in Burkina Faso were evaluated using archived serum samples and Treponema pallidum hemagglutination assay (TPHA) as the gold standard. Blood samples were collected between November 2011 and June 2012 from blood donors at the Regional Blood Transfusion Center of Ouagadougou. The sensitivity and specificity of the tests were calculated. Evaluation of operational characteristics such as clarity of pamphlet, complexity of technique, duration, was conducted in a first-level healthcare center with health workers in maternity unit. RESULTS: Alere DetermineTM Syphilis was the most sensitive of the four rapid syphilis tests evaluated. It was followed by SD Bioline Syphilis 3.0, Cypress Diagnostics Syphilis Quick test and Accu-Tell ® Rapid Anti-TP, which was the least sensitive. The four tests demonstrated a good diagnostic specificity for syphilis (95-98%), and healthcare workers found them easy to use. CONCLUSIONS: The study allowed confirming the good performance of three of four rapid syphilis tests in Burkina Faso. More research will be conducted to assess the feasibility of introducing selected rapid tests for syphilis in antenatal care services.

Antipneumococcal seroprevalence and pneumococcal carriage during a meningococcal epidemic in Burkina Faso, 2006.

BACKGROUND: To better understand the high incidence of pneumococcal meningitis in the African meningitis belt, we conducted a pneumococcal seroprevalence study during a meningococcal meningitis epidemic in Western Burkina Faso, March 2006. METHODS: In 3 villages experiencing epidemics, we included 624 healthy persons (1-39 years) by cluster sampling. We determined pneumococcal serum immunoglobulin G (IgG) antibody concentrations against 12 serotypes contained in 13-valent pneumococcal conjugate vaccine, and evaluated determinants for IgG ≥ 0.35 µg/mL by multivariate logistic regression. RESULTS: The percentage of subjects with serotype-specific IgG concentrations ≥0.35 µg/mL increased with age and was similar for the different serotypes: it was 20%-43% among 1-4-year-olds and 56%-90% among 20-39-year-olds. Prevalence of IgG ≥ 0.35 µg/mL against serotype 1 was up to 71% after age 10 years. During multivariate analyses, determinants of IgG concentrations ≥0.35 µg/mL varied by serotype; for 5 and 6 serotypes, respectively, female sex (around 2-fold increased odds) and cigarette smoking (about 5-fold reduced odds) predicted elevated titers. CONCLUSIONS: Despite a substantially higher historical pneumococcal meningitis incidence in Burkina Faso, the general population has an antibody seroprevalence against 12 pneumococcal serotypes similar to that reported from the United Kingdom. The role of putatively protective antibody seroprevalence in preventing pneumococcal meningitis in the meningitis belt requires more thorough evaluation.

A novel pharmacokinetic approach to predict virologic failure in HIV-1-infected paediatric patients.

OBJECTIVE: The objective of this study was to develop in children an HIV dynamic model able to predict simultaneously the viral load and CD4 lymphocyte evolutions, and to take into account, through a composite inhibition score, the relative contribution of each drug of the combination efavirenz-didanosine-lamivudine and use this score as a predictor of treatment failure in a multidrug therapy. DESIGN: Open phase II trial (BURKINAME - ANRS 12103) registered in the ClinicalTrials.gov database (http://clinicaltrials.gov) with the no. NCT00122538. METHODS: Forty-nine children aged from 2.5 to 15 years were administered once-daily dose of lamivudine, didanosine and efavirenz. The three drugs effect was then characterized by a composite inhibition score combining the effect of each drug, according to their site and mechanism of action and their relative contribution. RESULTS: Efavirenz was the most potent antiretroviral and was responsible for 65% of the total effect, and then didanosine for 23% and lamivudine was the less potent with 12% of the total observed effect. An EC90 for efavirenz was determined (3.3 mg/l). AUC90 was estimated for lamivudine and didanosine: 8.4 and 1.5 mg h/l, respectively. The composite inhibition score was the best predictor of virologic failure compared with the concentrations of each drug taken independently [hazard ratio (HR) 0.6 per 10% increase, 95% confidence interval (CI) 0.41-0.88]. CONCLUSION: The relative contributions of three combined drugs were assessed on plasma viral load and CD4 lymphocyte count kinetics in HIV-1-infected children. Pharmacokinetics targets have been suggested for lamivudine and didanosine. A composite inhibition score has been determined to be a high predictor of treatment failure in a multidrug therapy.

Seroprevalence of bactericidal, specific IgG antibodies and incidence of meningitis due to group A Neisseria meningitidis by age in Burkina Faso 2008.

BACKGROUND: We investigated serological correlates of protection against Neisseria meningitidis serogroup A (NmA) in Burkina Faso before the introduction of NmA conjugate vaccine. METHODOLOGY/PRINCIPAL FINDINGS: We collected blood from a representative sample (N = 1022) of Bobo-Dioulasso residents. Sera were evaluated for serum bactericidal antibody (SBA) activity against NmA strains of immunotype L11 (F8238) and L10 (3125) and NmA-specific IgG. Seroprevalence was compared to the age-specific NmA meningitis incidence in Bobo-Dioulasso during March 2007-February 2008. Meningococcal carriage was evaluated in a subset (N = 538). Geometric mean titres (GMT)/concentrations (GMC) of SBA and NmA-specific IgG increased with age, peaking around age 20 years. Overall, 70% of our sample had NmA-specific IgG ≥2 ug/mL. Meningitis incidence was highest in those aged <6 months and 5-19 years. No NmA carriers were found. Compared to the reference strain SBA, GMTs were higher against a locally isolated strain and around 40-fold lower against Dutch strain 3125. CONCLUSIONS/SIGNIFICANCE: This study provides estimates of natural immunity to NmA, according to a variety of antibody measures, which will be helpful in ascertaining antibody persistence after MenAfriVac™ introduction. Age-specific seroprevalence of reference strain SBA titres most likely reflects exposure to meningococci and consecutive reactive immunity. We could not define any serological correlate of protection.

Morbidity after antiretroviral therapy initiation in HIV-1-infected children in West Africa: temporal trends and relation to CD4 count.

BACKGROUND: Although 90% of HIV-1-infected children live in sub-Saharan Africa, morbidity data after highly active antiretroviral therapy (HAART) initiation in these settings are limited. The objective of this study was to document the incidence of AIDS-defining events and non-AIDS-defining diseases in African children receiving HAART. METHODS: Incidences rates (IRs) of AIDS-defining events and 10 other common diseases were estimated overall and by current CD4-strata (<15%, 15 - <25% and ≥25%) from 2 prospective cohorts of African children. RESULTS: One hundred eighty-eight children contributing to 355 children-years were included. The documented morbidity IRs per 100 children-years were upper respiratory infections, 100 (87-114); infectious diarrhea, 37 (31-44); World Health Organization (WHO) stage 2 events, 22.9 (18.2-28.1); and WHO stage 3/4 events, 12.3 (9.1-16.7). IRs of WHO stage 2 events, severe bacterial infections, infectious diarrhea and pneumonia decreased linearly across all CD4%-strata, whereas WHO stage 3/4 events and viral infections occurred mostly when CD4% <15%. Overall, IRs decreased during the first 2 years on HAART except for upper respiratory infection, mycosis and oral candidiasis. CONCLUSION: This incidence of AIDS- and non-AIDS-defining diseases declined substantially after HAART in 2 African cohorts, although estimates remained high compared with high-resource settings. Without renewed efforts to increase antiretroviral scale-up, children in developing countries will continue to have a high burden of infections.

[Characteristics of parent-adolescent communication about sexuality and HIV in Bobo-Dioulasso, Burkina Faso]. / Caractéristiques de la communication parents-adolescentes sur la sexualité et le VIH à Bobo-Dioulasso, Burkina Faso.

Adolescent females are a key target audience in the fight against sexually transmitted infections and HIV in sub-Saharan Africa. One issue is that families in Africa play a very limited role in sex education. The objective of this study was to examine parent-child communication from a qualitative perspective by exploring the characteristics and quality of parent-child communication. A cross-sectional study was conducted between April and September 2009 in Bobo-Dioulasso (Burkina Faso). The study included 40 parent-child pairs (50% of in-school children and 50% of out-of-school children). Individual interviews and focus groups were conducted. The data were analyzed using Stata version 9.1 (quantitative data) and QSR Nvivo 2.0 (qualitative data). The study found that 74% (14/19) of out-of-school children communicated with their parents, compared to just 45% of in-school children (p = 0.07). Mother-child communication was found to be the most common type of parent-child communication, with 59% (13/22) of families who communicated about sexuality and HIV preferring mother-child communication. Further research is needed to identify the factors determining better communication among out-of-school children.