Abdoul-Salam Ouédraogo

Human papillomavirus genotype distribution and cervical squamous intraepithelial lesions among high-risk women with and without HIV-1 infection in Burkina Faso

Human papillomavirus (HPV) infection and cervical squamous intraepithelial lesions (SILs) were studied in 379 high-risk women. Human papillomavirus DNA was detected in 238 of 360 (66.1%) of the beta-globin-positive cervical samples, and 467 HPV isolates belonging to 35 types were identified. Multiple (2–7 types) HPV infections were observed in 52.9% of HPV-infected women. The most prevalent HPV types were HPV-52 (14.7%), HPV-35 (9.4%), HPV-58 (9.4%), HPV-51 (8.6%), HPV-16 (7.8%), HPV-31 (7.5%), HPV-53 (6.7%), and HPV-18 (6.4%). Human immunodeficiency virus type 1 (HIV-1) seroprevalence was 36.0%. Human papillomavirus prevalence was significantly higher in HIV-1-infected women (87 vs 54%, prevalence ratio (PR)=1.61, 95% confidence interval (CI): 1.4–1.8). High-risk HPV types (71 vs 40%, PR=1.79, 95% CI: 1.5–2.2), in particular HPV-16+18 (22 vs 9%, PR=2.35, 95% CI: 1.4–4.0), and multiple HPV infections (56 vs 23%, PR=2.45, 95% CI: 1.8–3.3) were more prevalent in HIV-1-infected women. High-grade SIL (HSIL) was identified in 3.8% of the women. Human immunodeficiency virus type 1 infection was strongly associated with presence of HSIL (adjusted odds ratio=17.0; 95% CI 2.2–134.1, P=0.007) after controlling for high-risk HPV infection and other risk factors for HSIL. Nine of 14 (63%) HSIL cases were associated with HPV-16 or HPV-18 infection, and might have been prevented by an effective HPV-16/18 vaccine.

Baseline Meningococcal Carriage in Burkina Faso before the Introduction of a Meningococcal Serogroup A Conjugate Vaccine

ABSTRACT The serogroup A meningococcal conjugate vaccine MenAfriVac has the potential to confer herd immunity by reducing carriage prevalence of epidemic strains. To better understand this phenomenon, we initiated a meningococcal carriage study to determine the baseline carriage rate and serogroup distribution before vaccine introduction in the 1- to 29-year old population in Burkina Faso, the group chosen for the first introduction of the vaccine. A multiple cross-sectional carriage study was conducted in one urban and two rural districts in Burkina Faso in 2009. Every 3 months, oropharyngeal samples were collected from >5,000 randomly selected individuals within a 4-week period. Isolation and identification of the meningococci from 20,326 samples were performed by national laboratories in Burkina Faso. Confirmation and further strain characterization, including genogrouping, multilocus sequence typing, and porA-fetA sequencing, were performed in Norway. The overall carriage prevalence for meningococci was 3.98%; the highest prevalence was among the 15- to 19-year-olds for males and among the 10- to 14-year-olds for females. Serogroup Y dominated (2.28%), followed by serogroups X (0.44%), A (0.39%), and W135 (0.34%). Carriage prevalence was the highest in the rural districts and in the dry season, but serogroup distribution also varied by district. A total of 29 sequence types (STs) and 51 porA-fetA combinations were identified. The dominant clone was serogroup Y, ST-4375, P1.5-1,2-2/F5-8, belonging to the ST-23 complex (47%). All serogroup A isolates were ST-2859 of the ST-5 complex with P1.20,9/F3-1. This study forms a solid basis for evaluating the impact of MenAfriVac introduction on serogroup A carriage.

Review of STI and HIV epidemiological data from 1990 to 2001 in urban Burkina Faso: implications for STI and HIV control

Objectives: To better understand the sexually transmitted infection (STI)/HIV dynamics in an urban west African setting in order to adapt STI/HIV control efforts accordingly. Methods: Review of STI and HIV epidemiological studies performed over the past decade in Bobo-Dioulasso, the second city of Burkina Faso. Trends in STI prevalence among commercial sex workers and the general population were assessed over time through studies that used the same recruitment and laboratory diagnostic procedures. Variations in aetiologies of vaginal discharge, urethral discharge, and genital ulcers were also evaluated among patients consulting for genital infection complaints. Antenatal clinic based surveys provided data to assess HIV trend among the general population. Results: We observed an important decline of classic bacterial STI such as syphilis, Neisseria gonorrhoea, Chlamydia trachomatis, and Haemophilus ducrey infections in all study groups. Trichomoniasis also declined but to a lesser extent. HIV infection followed the same trend at the same time, with a significant decline in the 15–19 year age group of pregnant women, suggesting a possible decrease of HIV incidence. Although no evidence of a causal relation can be drawn from this review, adoption of safer sex behaviour, introduction of the syndromic management (SM) approach, or higher antibiotic use may have contributed to these changes. Conclusions: Classic bacterial STI declined over the past decade in parallel with a stabilisation of HIV infection. Variations in syndromes aetiology and sexual behaviours should be monitored as part of STI surveillance in order to improve STI syndromic management algorithms and to adapt HIV/STI prevention efforts.

Persistent low carriage of serogroup A Neisseria meningitidis two years after mass vaccination with the meningococcal conjugate vaccine, MenAfriVac

BackgroundThe conjugate vaccine against serogroup A Neisseria meningitidis (NmA), MenAfriVac, is currently being introduced throughout the African meningitis belt. In repeated multicentre cross-sectional studies in Burkina Faso we demonstrated a significant effect of vaccination on NmA carriage for one year following mass vaccination in 2010. A new multicentre carriage study was performed in October-November 2012, two years after MenAfriVac mass vaccination.MethodsOropharyngeal samples were collected and analysed for presence of N. meningitidis (Nm) from a representative selection of 1-29-year-olds in three districts in Burkina Faso using the same procedures as in previous years. Characterization of Nm isolates included serogrouping, multilocus sequence typing, and porA and fetA sequencing. A small sample of invasive isolates collected during the epidemic season of 2012 through the national surveillance system were also analysed.ResultsFrom a total of 4964 oropharyngeal samples, overall meningococcal carriage prevalence was 7.86%. NmA prevalence was 0.02% (1 carrier), significantly lower (OR, 0.05, P = 0.005, 95% CI, 0.006-0.403) than pre-vaccination prevalence (0.39%). The single NmA isolate was sequence type (ST)-7, P1.20,9;F3-1, a clone last identified in Burkina Faso in 2003. Nm serogroup W (NmW) dominated with a carriage prevalence of 6.85%, representing 87.2% of the isolates. Of 161 NmW isolates characterized by molecular techniques, 94% belonged to the ST-11 clonal complex and 6% to the ST-175 complex. Nm serogroup X (NmX) was carried by 0.60% of the participants and ST-181 accounted for 97% of the NmX isolates. Carriage prevalence of serogroup Y and non-groupable Nm was 0.20% and 0.18%, respectively. Among the 20 isolates recovered from meningitis cases, NmW dominated (70%), followed by NmX (25%). ST-2859, the only ST with a serogroup A capsule found in Burkina Faso since 2004, was not found with another capsule, neither among carriage nor invasive isolates.ConclusionsThe significant reduction of NmA carriage still persisted two years following MenAfriVac vaccination, and no cases of NmA meningitis were recorded. High carriage prevalence of NmW ST-11 was consistent with the many cases of NmW meningitis in the epidemic season of 2012 and the high proportion of NmW ST-11 among the characterized invasive isolates.

Effect of HIV-1 and antiretroviral therapy on herpes simplex virus type 2: a prospective study in African women.

Objectives: To document the natural history of herpes simplex virus type 2 (HSV-2) in relation to HIV and highly active antiretroviral therapy (HAART) in Africa, a longitudinal study was conducted of women in the placebo arms of two randomised controlled trials of HSV-suppressive therapy in Burkina Faso. Methods: 22 HIV-uninfected women (group 1), 30 HIV-1-infected women taking HAART (group 2), and 68 HIV-1-infected women not eligible for HAART (group 3) were followed over 24 weeks. HSV-2 DNA was detected on alternate weeks using real-time PCR from cervicovaginal lavages. Plasma HIV-1 RNA was measured every month. CD4 cell counts were measured at enrolment. Results: Ulcers occurred on 1.9%, 3.1% and 7.2% of visits in groups 1, 2 and 3 (p = 0.02). Cervicovaginal HSV-2 DNA was detected in 45.5%, 63.3% and 67.6% of women (p = 0.11), and on 4.3%, 9.7% and 15.5% of visits in the three groups (p<0.001). Among HIV-infected women, cervicovaginal HSV-2 DNA was detected more frequently during ulcer episodes (adjusted risk ratio (aRR) 2.79, 95% CI 2.01 to 3.86) and less frequently among women practising vaginal douching (aRR 0.60, 95% CI 0.40 to 0.91). Compared with women not taking HAART and with CD4 cell counts of 500 cells/μl or greater, women on HAART had a similar risk of HSV-2 shedding (aRR 0.95, 95% CI 0.52 to 1.73), whereas women with CD4 cell counts of 200–500 cells/μl were more likely to shed HSV-2 (aRR 1.71, 95% CI 1.02 to 2.86). Conclusions: HSV-2 reactivations occur more frequently among HIV-infected women, particularly those with low CD4 cell counts, and are only partly reduced by HAART. HSV therapy may benefit HIV-infected individuals during HAART.

Performance of Xpert MTB/RIF and Alternative Specimen Collection Methods for the Diagnosis of Tuberculosis in HIV-Infected Children

BACKGROUND The diagnosis of tuberculosis in human immunodeficiency virus (HIV)-infected children is challenging. We assessed the performance of alternative specimen collection methods for tuberculosis diagnosis in HIV-infected children using Xpert MTB/RIF (Xpert). METHODS HIV-infected children aged ≤13 years with suspected intrathoracic tuberculosis were enrolled in 8 hospitals in Burkina Faso, Cambodia, Cameroon, and Vietnam. Gastric aspirates were taken for children aged <10 years and expectorated sputum samples were taken for children aged ≥10 years (standard samples); nasopharyngeal aspirate and stool were taken for all children, and a string test was performed if the child was aged ≥4 years (alternative samples). All samples were tested with Xpert. The diagnostic accuracy of Xpert for culture-confirmed tuberculosis was analyzed in intention-to-diagnose and per-protocol approaches. RESULTS Of 281 children enrolled, 272 (96.8%) had ≥1 specimen tested with Xpert (intention-to-diagnose population), and 179 (63.5%) had all samples tested with Xpert (per-protocol population). Tuberculosis was culture-confirmed in 29/272 (10.7%) children. Intention-to-diagnose sensitivities of Xpert performed on all, standard, and alternative samples were 79.3% (95% confidence interval [CI], 60.3-92.0), 72.4% (95% CI, 52.8-87.3), and 75.9% (95% CI, 56.5-89.7), respectively. Specificities were ≥97.5%. Xpert combined on nasopharyngeal aspirate and stool had intention-to-diagnose and per-protocol sensitivities of 75.9% (95% CI, 56.5-89.7) and 75.0% (95% CI, 47.6-92.7), respectively. CONCLUSIONS The combination of nasopharyngeal aspirate and stool sample is a promising alternative to methods usually recommended by national programs. Xpert performed on respiratory and stools samples enables rapid confirmation of tuberculosis diagnosis in HIV-infected children. CLINICAL TRIALS REGISTRATION The ANRS (Agence Nationale de Recherche sur le Sida) 12229 PAANTHER (Pediatric Asian African Network for Tuberculosis and HIV Research) 01 study is registered at ClinicalTrials.gov (NCT01331811).

Phenotypic and genotypic characterization of meningococcal carriage and disease isolates in Burkina Faso after mass vaccination with a serogroup a conjugate vaccine

BackgroundThe conjugate vaccine against serogroup A Neisseria meningitidis (NmA), MenAfriVac, was first introduced in mass vaccination campaigns of the 1-29-year-olds in Burkina Faso in 2010. The aim of this study was to genetically characterize meningococcal isolates circulating in Burkina Faso before and up to 13 months after MenAfriVac mass vaccination.MethodsA total of 1,659 meningococcal carriage isolates were collected in a repeated cross-sectional carriage study of the 1-29-year-olds in three districts of Burkina Faso in 2010 and 2011, before and up to 13 months after mass vaccination. Forty-two invasive isolates were collected through the national surveillance in Burkina Faso in the same period. All the invasive isolates and 817 carriage isolates were characterized by serogroup, multilocus sequence typing and porA-fetA sequencing.ResultsSeven serogroup A isolates were identified, six in 2010, before vaccination (4 from carriers and 2 from patients), and one in 2011 from an unvaccinated patient; all were assigned to sequence type (ST)-2859 of the ST-5 clonal complex. No NmA carriage isolate and no ST-2859 isolate with another capsule were identified after vaccination. Serogroup X carriage and disease prevalence increased before vaccine introduction, due to the expansion of ST-181, which comprised 48.5% of all the characterized carriage isolates. The hypervirulent serogroup W ST-11 clone that was responsible for most of meningococcal disease in 2011 and 2012 was not observed in 2010; it appeared during the epidemic season of 2011, when it represented 40.6% of the serogroup W carriage isolates.ConclusionsSuccessive clonal waves of ST-181 and ST-11 may explain the changing epidemiology in Burkina Faso after the virtual disappearance of NmA disease and carriage. No ST-2859 strain of any serogroup was found after vaccination, suggesting that capsule switching of ST-2859 did not occur, at least not during the first 13 months after vaccination.

Longitudinal effect following initiation of highly active antiretroviral therapy on plasma and cervico-vaginal HIV-1 RNA among women in Burkina Faso

Background: Highly active antiretroviral therapy (HAART) could decrease HIV-1 transmissibility by reducing genital and plasma HIV-1 RNA. Methods: We evaluated the effect of HAART on genital and plasma HIV-1 RNA in a cohort of 39 antiretroviral-naïve women in Burkina Faso. Cervico-vaginal lavages were collected before HAART initiation and at six visits over 28 weeks while on HAART. Blood samples were collected at baseline and at three and four visits for CD4 and plasma HIV-1 RNA measurements, respectively. Results: Before HAART, 72% of women had detectable genital HIV-1 RNA. After 18 weeks on HAART, only one woman (2.5%) had detectable plasma HIV-1 RNA and two women (5.1%) had detectable genital HIV-1 RNA. Similar results were observed at each follow-up visit. However, 16/34 (47%) women with consistently undetectable plasma HIV-1 RNA shed HIV-1 at least once between weeks 18 and 28. In samples with detectable genital HIV-1, the mean quantity of HIV-1 RNA decreased from 3.87 prior to HAART to 3.04 log10 copies/mL at last visit (median 29 weeks; a 6.8-fold decrease in absolute number of copies/mL) (p = 0.04). A significant median CD4 lymphocyte cell gain of 121 cells/μL (interquartile range 59 to 204) was measured between pre-HAART and last visit. Conclusion: These findings suggest that HAART could play a role in reducing HIV transmission in Africa; however, they underscore the need to emphasise safe sex practices with patients taking HAART.

Carriage of Neisseria lactamica in 1- to 29-Year-Old People in Burkina Faso: Epidemiology and Molecular Characterization

ABSTRACT Neisseria lactamica is a true commensal bacterium occupying the same ecological niche as the pathogenic Neisseria meningitidis, which is responsible for outbreaks and large epidemics, especially in sub-Saharan Africa. To better understand the epidemiology of N. lactamica in Africa and its relationship to N. meningitidis, we studied N. lactamica carriage in 1- to 29-year-old people living in three districts of Burkina Faso from 2009 to 2011. N. lactamica was detected in 18.2% of 45,847 oropharyngeal samples. Carriage prevalence was highest among the 2-year-olds (40.1%) and decreased with age. Overall prevalence was higher for males (19.1%) than females (17.5%) (odds ratio [OR], 1.11; 95% confidence interval [CI], 1.04 to 1.18), while among the 18- to 29-year-olds, carriage prevalence was significantly higher in women (9.1%) than in men (3.9%) (OR, 2.49; 95% CI, 1.94 to 3.19). Carriage prevalence of N. lactamica was remarkably homogeneous in the three districts of Burkina Faso and stable over time, in comparison with carriage of N. meningitidis (P. A. Kristiansen et al., Clin. Vaccine Immunol. 18:435–443, 2011). There was no significant seasonal variation of N. lactamica carriage and no significant change in carriage prevalence after introduction of the serogroup A meningococcal conjugate vaccine, MenAfriVac. Multilocus sequence typing was performed on a selection of 142 isolates. The genetic diversity was high, as we identified 62 different genotypes, of which 56 were new. The epidemiology of N. lactamica carriage and the molecular characteristics of carried isolates were similar to those reported from industrialized countries, in contrast to the particularities of N. meningitidis carriage and disease epidemiology in Burkina Faso.

The Establishment and Diversification of Epidemic-Associated Serogroup W Meningococcus in the African Meningitis Belt, 1994 to 2012

Meningococcal disease (meningitis and bloodstream infections) threatens millions of people across the meningitis belt of sub-Saharan Africa. A vaccine introduced in 2010 protects against Africa’s then-most common cause of meningococcal disease, N. meningitidis serogroup A. However, other serogroups continue to cause epidemics in the region—including serogroup W. The rapid identification of strains that have been associated with prior outbreaks can improve the assessment of outbreak risk and enable timely preparation of public health responses, including vaccination. Phylogenetic analysis of newly sequenced serogroup W strains isolated from 1994 to 2012 identified two groups of strains linked to large epidemics in Burkina Faso, one being descended from a strain that caused an outbreak during the Hajj pilgrimage in 2000. We find that applying whole-genome sequencing to meningococcal disease surveillance collections improves the discrimination among strains, even within a single nation-wide epidemic, which can be used to better understand pathogen spread. ABSTRACT Epidemics of invasive meningococcal disease (IMD) caused by meningococcal serogroup A have been eliminated from the sub-Saharan African so-called “meningitis belt” by the meningococcal A conjugate vaccine (MACV), and yet, other serogroups continue to cause epidemics. Neisseria meningitidis serogroup W remains a major cause of disease in the region, with most isolates belonging to clonal complex 11 (CC11). Here, the genetic variation within and between epidemic-associated strains was assessed by sequencing the genomes of 92 N. meningitidis serogroup W isolates collected between 1994 and 2012 from both sporadic and epidemic IMD cases, 85 being from selected meningitis belt countries. The sequenced isolates belonged to either CC175 (n = 9) or CC11 (n = 83). The CC11 N. meningitidis serogroup W isolates belonged to a single lineage comprising four major phylogenetic subclades. Separate CC11 N. meningitidis serogroup W subclades were associated with the 2002 and 2012 Burkina Faso epidemics. The subclade associated with the 2012 epidemic included isolates found in Burkina Faso and Mali during 2011 and 2012, which descended from a strain very similar to the Hajj (Islamic pilgrimage to Mecca)-related Saudi Arabian outbreak strain from 2000. The phylogeny of isolates from 2012 reflected their geographic origin within Burkina Faso, with isolates from the Malian border region being closely related to the isolates from Mali. Evidence of ongoing evolution, international transmission, and strain replacement stresses the importance of maintaining N. meningitidis surveillance in Africa following the MACV implementation. IMPORTANCE Meningococcal disease (meningitis and bloodstream infections) threatens millions of people across the meningitis belt of sub-Saharan Africa. A vaccine introduced in 2010 protects against Africa’s then-most common cause of meningococcal disease, N. meningitidis serogroup A. However, other serogroups continue to cause epidemics in the region—including serogroup W. The rapid identification of strains that have been associated with prior outbreaks can improve the assessment of outbreak risk and enable timely preparation of public health responses, including vaccination. Phylogenetic analysis of newly sequenced serogroup W strains isolated from 1994 to 2012 identified two groups of strains linked to large epidemics in Burkina Faso, one being descended from a strain that caused an outbreak during the Hajj pilgrimage in 2000. We find that applying whole-genome sequencing to meningococcal disease surveillance collections improves the discrimination among strains, even within a single nation-wide epidemic, which can be used to better understand pathogen spread.