Optimizing the World Health Organization algorithm for HIV vertical transmission risk assessment by adding maternal self-reported antiretroviral therapy adherence.

BACKGROUND: The World Health Organization (WHO) risk assessment algorithm for vertical transmission of HIV (VT) assumes the availability of maternal viral load (VL) result at delivery and early viral control 4 weeks after initiating antiretroviral treatment (ART). However, in many low-and-middle-income countries, VL is often unavailable and mothers' ART adherence may be suboptimal. We evaluate the inclusion of the mothers' self-reported adherence into the established WHO-algorithm to identify infants eligible for enhanced post-natal prophylaxis when mothers' VL result is not available at delivery. METHODS: We used data from infants with perinatal HIV infection and their mothers enrolled from May-2018 to May-2020 in Mozambique, South Africa, and Mali. We retrospectively compared the performance of the WHO-algorithm with a modified algorithm which included mothers' adherence as an additional factor. Infants were considered at high risk if born from mothers without a VL result in the 4 weeks before delivery and with adherence <90%. RESULTS: At delivery, 143/184(78%) women with HIV knew their status and were on ART. Only 17(12%) obtained a VL result within 4 weeks before delivery, and 13/17(76%) of them had VL ≥1000 copies/ml. From 126 women on ART without a recent VL result, 99(79%) had been on ART for over 4 weeks. 45/99(45%) women reported suboptimal (< 90%) adherence. A total of 81/184(44%) infants were classified as high risk of VT as per the WHO-algorithm. The modified algorithm including self-adherence disclosure identified 126/184(68%) high risk infants. CONCLUSIONS: In the absence of a VL result, mothers' self-reported adherence at delivery increases the number of identified infants eligible to receive enhanced post-natal prophylaxis.

Characterization of drug resistance and the defective HIV reservoir in virally suppressed vertically infected children in Mali.

BACKGROUND: In the perspective of ART-free HIV remission, vertically infected children treated with suppressive ART from early infancy represent an optimal population model to better understand the genetic complexity of the reservoir. OBJECTIVES: To evaluate the proportion of defective viral population and the genotypic resistance patterns in cell-associated HIV DNA. METHODS: In a cohort including 93 ART-treated vertically HIV-infected (VHIV) children in Mali with plasma HIV-1 RNA ≤50 copies/mL for at least 6 months, we studied total HIV DNA, percentage of defective genomes and resistance by reverse transcriptase and protease bulk sequencing from whole blood in dried blood spots. RESULTS: Children had a median age of 9.9 years at the time of inclusion (IQR = 7.6-13.4) and 3.3 years (IQR = 2-7) at ART initiation; median ART duration was 5.5 years (IQR = 3.7-7.3). The median level of total HIV DNA was 470 copies/106 cells with one patient presenting undetectable HIV DNA (<66 copies/106 cells). We observed the presence of at least one stop codon in viruses from 34 patients (37%). The presence of stop codons was not correlated with the level of HIV DNA or duration of ART. We showed a high prevalence of HIV-1 resistance in DNA with 26% of children harbouring virus resistant to at least one NRTI and 40% to at least one NNRTI. CONCLUSIONS: While these VHIV children were successfully treated for a long time, they showed high prevalence of resistance in HIV DNA and a moderate defective HIV reservoir.

Qualitative and quantitative HIV antibodies and viral reservoir size characterization in vertically infected children with virological suppression.

Background: Absence of detectable viraemia after treatment cessation in some vertically HIV-infected (VHIV) children suggests that early initiation of HAART could lead to functional cure. Objectives: We described the factors associated with HIV antibody levels and the viral reservoir size in HAART-treated VHIV children. Methods: Study included 97 VHIV children with virological suppression, in Bamako, Mali. The anti-gp41 antibody activities and HIV serostatus were assessed. The viral reservoir size was measured by quantifying total cell-associated HIV DNA. Results: Among the children studied, the median total HIV DNA level was 445 copies/10 6 cells (IQR = 187-914) and the median anti-gp41 antibody activity was 0.29 OD (IQR = 0.18-0.75). Low activity of anti-gp41 antibodies was associated with a younger age of HAART initiation ( P = 0.01). Overall, eight HIV-1 seroreversions were identified. Conclusions: Study identified potential candidates with low viral reservoir and low antibody levels or activities for future trials aiming to reduce HIV-1 reservoir to limit HAART duration.

Seroprevalence of Crimean-Congo hemorrhagic fever virus among people living with HIV in Brazzaville, Congo and among blood donors in Bamako, Mali.

Crimean-Congo hemorrhagic fever virus (CCHFV) is the causative agent of Crimean-Congo hemorrhagic fever (CCHF), a highly contagious and potentially fatal emerging disease. We assessed CCHFV seroprevalence by conducting a serological survey of two cohorts from Brazzaville, Congo and Bamako, Mali. We retrospectively screened 581 sera samples, including 352 from monitoring centers for people living with HIV (PLWH) in Brazzaville and 229 provided by the Blood Transfusion Center at Gabriel Touré Hospital in Bamako. An ELISA kit (ID Screen® CCHF Double Antigen Multi-species, Innovative Diagnostics) was used to detect total anti-CCHFV antibodies in serum. CCHFV seroprevalence was 0.6% in the PLWH cohort in Brazzaville, all in a peri­urban area near livestock/agriculture, and 1.75% in a cohort of blood donors in Bamako, half living in a peri­urban area near livestock/agriculture and the others performing risk-exposure activities, such as working as a butcher or with frequent rural travels. PLWH from Brazzaville were mostly female, older, and more highly educated, with a tertiary sector activity and living in an urban biotope without livestock/agricultural activities in the surroundings, in contrast to the blood donors of Bamako, who were younger and more likely to live in peri­urban/rural areas with livestock/agricultural activities in the surroundings. Despite a low CCHFV seroprevalence, our study indicates human contact with CCHFV in sub-urban areas of the capital cities of Congo and Mali associated with previously described CCHFV risk factors.

Genomic characterization of SARS-CoV-2 in Guinea, West Africa.

SARS-CoV-2 has claimed several million lives since its emergence in late 2019. The ongoing evolution of the virus has resulted in the periodic emergence of new viral variants with distinct fitness advantages, including enhanced transmission and immune escape. While several SARS-CoV-2 variants of concern trace their origins back to the African continent-including Beta, Eta, and Omicron-most countries in Africa remain under-sampled in global genomic surveillance efforts. In an effort to begin filling these knowledge gaps, we conducted retrospective viral genomic surveillance in Guinea from October 2020 to August 2021. We found that SARS-CoV-2 clades 20A, 20B, and 20C dominated throughout 2020 until the coincident emergence of the Alpha and Eta variants of concern in January 2021. The Alpha variant remained dominant throughout early 2021 until the arrival of the Delta variant in July. Surprisingly, despite the small sample size of our study, we also found the persistence of the early SARS-CoV-2 clade 19B as late as April 2021. Together, these data help fill in our understanding of the SARS-CoV-2 population dynamics in West Africa early in the COVID-19 pandemic.

Development and field evaluation in African and Asian countries of an hepatitis B virus PCR on open polyvalent platforms to determine treatment eligibility: results from the "Agence Nationale de Recherche sur le Sida et les hépatites" 12327 study.

OBJECTIVES: Widespread testing and treatment are essential to eliminate hepatitis B virus (HBV) infection as a public health concern. However, in resource-limited countries, access to HBV PCR is limited. In this study, we developed a quantitative HBV PCR assay on open molecular platforms and evaluate its performance in diagnosing clinically significant HBV DNA thresholds as defined by the WHO (2000 IU/mL, 20 000 IU/mL, and 200 000 IU/mL). METHODS: We implemented our HBV PCR test in seven African and Asian countries and France, using either an in-house laboratory method or a European conformity for in vitro diagnostic (CE-IVD) marked version of the PCR (Generic HBV Charge Virale, Biocentric). Results were compared with reference tests (Roche Cobas AmpliPrep/Cobas TaqMan and Abbott RealTime on Abbott m2000). RESULTS: There was a good agreement between the HBV DNA results of 1015 samples tested by the PCR on open polyvalent platforms and the results from reference tests (mean difference (bias ± standard deviation [SD]): -0.3 ± 0.7 log10 IU/mL and -0.2 ± 0.9 log10 IU/mL when compared with Roche and Abbott tests, respectively). Kappa-Cohen agreements between the HBV PCR on open polyvalent platforms and the Roche/Abbott assays appeared almost perfect for HBV DNA levels ranged from >20 000 to 200 000 IU/mL and >200 000 IU/mL, substantial and moderate for HBV DNA levels ranged from 2000 to 20 000 IU/mL when compared with Abbott and Roche, respectively. The assay's performance was consistent across genotypes A, B, C, D, and E. DISCUSSION: This field evaluation showed that our HBV PCR test is a valuable alternative to proprietary PCR systems. PCR assays on open platforms contribute to expanding clinical laboratory solutions for diagnosing individuals who meet the viral load criteria for antiviral therapy (>20 000 IU/mL) and mother-to-child prophylaxis (>200 000 IU/mL).

Metabolic and Immune Consequences of Antibiotic Related Microbiome Alterations during first-line Tuberculosis Treatment in Bamako, Mali.

Background: Tuberculosis (TB) infection is known to lead to the unbalance of the gut microbiota and act synergistically on the decline of the host immune response, when untreated. Moreover, previous work has found a correlation between dysbiosis in the gut microbiota composition and the use of antibiotics. However, there is a need for an in-depth understanding of the metabolic and immune consequences of antibiotic-related microbiome alterations during first-line TB treatment. Methods: In a longitudinal cohort study, which included TB-infected cohorts and healthy individuals (control group), we studied the anti-TB-related changes in the gut microbiota composition and related functional consequences. Sputum, whole blood and stool samples were collected from participants at four time-points including before (Month-0), during (Month-2), at the end of drug treatment (Month-6) and 9 months after treatment (Month-15). Controls were sampled at inclusion and Month-6. We analyzed the microbiota composition and microbial functional pathways with shotgun metagenomics, analyzed the blood metabolomics using high-performance liquid chromatography (HPLC), and measured the levels of metabolites and cytokines with cytometric bead array. Results: We found that the gut microbiota of patients infected with TB was different from that of the healthy controls. The gut microbiota became similar to healthy controls after treatment but was still significantly different after 6 months treatment and at the follow up 9 months after treatment. Our data also showed disturbance in the plasma metabolites such as tryptophan and tricarboxylic acids components of patients during TB treatment. Levels of IL-4, IL-6, IL-10, and IFN-γ decreased during treatment and levels were maintained after treatment completion, while IL-17A known to have a strong link with the gut microbiota was highly expressed during treatment period and longer than the 9-month post treatment completion. We found that some fatty acids were negatively correlated with the abundance of taxa. For example, Roseburia, Megasphaera, and alpha proteobacterium HIMB5 species were negatively correlated (rho = -0.6) with the quinolinate production. Conclusion: Changes in the composition and function of gut microbiota was observed in TB patients before and after treatment compared to healthy controls. The differences persisted at nine months after treatment completion. Alterations in some bacterial taxa were correlated to the changes in metabolite levels in peripheral blood, thus the altered microbial community might lead to changes in immune status that influence the disease outcome and future resistance to infections.

Characterization of HIV-1 antiretroviral drug resistance after second-line treatment failure in Mali, a limited-resources setting.

OBJECTIVES: We describe the outcomes of second-line drug resistance profiles and predict the efficacy of drugs for third-line therapy in patients monitored without the benefit of plasma HIV-1 RNA viral load (VL) or resistance testing. METHODS: We recruited 106 HIV-1-infected patients after second-line treatment failure in Mali. VL was determined by the Abbott RealTime system and the resistance by the ViroSeq HIV-1 genotyping system. The resistance testing was interpreted using the latest version of the Stanford algorithm. RESULTS: Among the 106 patients, 93 had isolates successfully sequenced. The median age, VL and CD4 cells were respectively 35 years, 72 000 copies/mL and 146 cells/mm(3). Patients were exposed to a median of 4 years of treatment and to six antiretrovirals. We found 20% of wild-type viruses. Resistance to etravirine was noted in 38%, to lopinavir in 25% and to darunavir in 12%. The duration of prior nucleos(t)ide reverse transcriptase inhibitor exposure was associated with resistance to abacavir (P < 0.0001) and tenofovir (P = 0.0001), and duration of prior protease inhibitor treatment with resistance to lopinavir (P < 0.0001) and darunavir (P = 0.06). CONCLUSION: Long duration of therapy prior to failure was associated with high levels of resistance and is directly related to limited access to VL monitoring and delayed switches to second-line treatment, precluding efficacy of drugs for third-line therapy. This study underlines the need for governments and public health organizations to recommend the use of VL monitoring and also the availability of darunavir and raltegravir for third-line therapies in the context of limited-resource settings.

Primaquine as a Candidate for HHV-8-Associated Primary Effusion Lymphoma and Kaposi's Sarcoma Treatment.

Human Herpesvirus 8 (HHV-8) is associated with three main severe orphan malignancies, Kaposi's sarcoma (KS), multicentric Castleman's disease (MCD), and primary effusion lymphoma (PEL), which present few therapeutic options. We identified the antimalarial primaquine diphosphate (PQ) as a promising therapeutic candidate for HHV-8-associated PEL and KS. Indeed, PQ strongly reduced cell viability through caspase-dependent apoptosis, specifically in HHV-8-infected PEL cells. Reactive oxygen species (ROS)- and endoplasmic reticulum (ER) stress-mediated apoptosis signaling pathways were found to be part of the in vitro cytotoxic effect of PQ. Moreover, PQ treatment had a clinically positive effect in a nonobese diabetic (NOD)/SCID xenograft PEL mouse model, showing a reduction in tumor growth and an improvement in survival. Finally, an exploratory proof-of-concept clinical trial in four patients harboring severe KS was conducted, with the main objectives to assess the efficacy, the safety, and the tolerability of PQ, and which demonstrated a positive efficacy on Kaposi's sarcoma-related lesions and lymphedema.

Machine learning outperformed logistic regression classification even with limit sample size: A model to predict pediatric HIV mortality and clinical progression to AIDS.

Logistic regression (LR) is the most common prediction model in medicine. In recent years, supervised machine learning (ML) methods have gained popularity. However, there are many concerns about ML utility for small sample sizes. In this study, we aim to compare the performance of 7 algorithms in the prediction of 1-year mortality and clinical progression to AIDS in a small cohort of infants living with HIV from South Africa and Mozambique. The data set (n = 100) was randomly split into 70% training and 30% validation set. Seven algorithms (LR, Random Forest (RF), Support Vector Machine (SVM), K-Nearest Neighbor (KNN), Naïve Bayes (NB), Artificial Neural Network (ANN), and Elastic Net) were compared. The variables included as predictors were the same across the models including sociodemographic, virologic, immunologic, and maternal status features. For each of the models, a parameter tuning was performed to select the best-performing hyperparameters using 5 times repeated 10-fold cross-validation. A confusion-matrix was built to assess their accuracy, sensitivity, and specificity. RF ranked as the best algorithm in terms of accuracy (82,8%), sensitivity (78%), and AUC (0,73). Regarding specificity and sensitivity, RF showed better performance than the other algorithms in the external validation and the highest AUC. LR showed lower performance compared with RF, SVM, or KNN. The outcome of children living with perinatally acquired HIV can be predicted with considerable accuracy using ML algorithms. Better models would benefit less specialized staff in limited resources countries to improve prompt referral in case of high-risk clinical progression.

High Prevalence of Anal Oncogenic Human Papillomavirus Infection in Young Men Who Have Sex with Men Living in Bamako, Mali.

BACKGROUND: High-risk human papillomavirus (HR-HPV) anal infection is a major problem among men who have sex with men (MSM) living in sub-Saharan Africa. The prevalence of anal HR-HPV infection and associated risk factors were estimated in a cross-sectional study in MSM living in Bamako, Mali. METHODS: MSM consulting at sexual health center of the National NGO Soutoura, Bamako, were prospectively included. Sociodemographic and clinical-biological data were collected. HPV detection and genotyping were performed from anal swabs using multiplex real-time PCR. Risk factors associated with anal HPV infection were assessed by logistic regression analysis. RESULTS: Fifty MSM (mean age, 24.2 years; range, 18-35) of which 32.0% were infected with HIV-1, were prospectively included. The overall prevalence of anal HPV infection of any genotypes was 70.0% (35/50) with 80.0% (28/35) of swabs positive for HR-HPV. HR-HPV-58 was the most detected genotype [13/35 (37.1%)], followed by HR-HPV-16 and low-risk (LR)-HPV-6 [12/35 (34.2%)], LR-HPV-40 [10/35 (28.6%)], LR-HPV-11 [9/35 (25.7%)], HR-HPV-51 [8/35 (22.8%)], HR-HPV types 18 and 39 [7/35 (20.0%)] and LR-HPV-43 [6/35 (17.1%)]. HR-HPV-52 and LR-HPV-44 were detected in lower proportions [5/35 (14.3%) and 4/35 (11.4%), respectively]. LR-HPV-42, LR-HPV-54, HR-HPV-31 and HR-HPV-35 were detected in very low proportions [3/35 (8.5%)]. Multiple HR-HPV infections were diagnosed in one-third of anal samples [16/50 (32.0%)], including around half of HR-HPV-positive anal swabs [16/35 (45.7%)]. More than half [27/50 (54.0%)] swabs were infected by at least one of HPV genotypes targeted by Gardasil-9® vaccine, including a majority of vaccine HR-HPV [22/50 (44.0%)]. In multivariate analysis, participation to sex in group was associated with anal infection by multiple HPV (aOR: 4.5, 95% CI: 1.1-18.1%; P = 0.032), and HIV-1 infection was associated with anal shedding of multiple HR-HPV (aOR: 5.5, 95% CI: 1.3-24.5%; P = 0.024). CONCLUSIONS: These observations indicate that the MSM community living in Bamako is at high-risk for HR-HPV anal infections, with a unique epidemiological HPV genotypes profile and high prevalence of anal HPV covered by the Gardasil-9® vaccine. Scaling up prevention strategies against HPV infection and related cancers adapted to this highly vulnerable MSM community should be urgently prioritized with innovative interventions.

Resistance-associated mutations to etravirine (TMC-125) in antiretroviral-naïve patients infected with non-B HIV-1 subtypes.

Susceptibility to etravirine (ETR), an expanded-spectrum nonnucleoside reverse transcriptase inhibitor (NNRTI), is dependent on the type and number of NNRTI resistance-associated mutations (RAMs). Studies have shown that some HIV-1 subtypes may have natural polymorphisms described as ETR RAMs. This study addresses the prevalence of ETR RAMs in treatment-naïve patients infected with HIV-1 non-B subtypes and its potential impact on ETR susceptibility. The prevalence of ETR RAMs in 726 antiretroviral-naïve patients infected with non-B HIV-1 subtypes was studied. ETR genotypic resistance was interpreted according to Agence Nationale de Recherches sur le SIDA and Stanford algorithms. NNRTI phenotypic susceptibilities of samples with at least one ETR RAM were measured. Overall, 75 (10.3%) of 726 sequences harbored at least one ETR RAM: sequences from 72 patients (10%) each had one ETR RAM, and sequences from 3 patients (0.4%) each had two ETR RAMs (V90I and Y181C in one case and V90I and A98G in two cases). None of the viruses had three or more ETR RAMs, and none were consequently classified as resistant to ETR. All sequences with two ETR RAMs belonged to subtype CRF02_AG. The presence of one ETR RAM was statistically more frequent in subtype CRF02_AG than in other non-B subtypes (P=0.004). Three new mutation profiles (E138A and V179I, Y181C and H221Y, and V90I and Y181C) showing decreased ETR phenotypic susceptibility were identified. In conclusion, although the prevalence of ETR RAMs in treatment-naïve patients infected with non-B HIV-1 subtypes was 10%, in most cases this had no significant impact on ETR susceptibility. However, the transmission of drug-resistant viruses with Y181C in a non-B genetic background has a potential for impact on ETR susceptibility.

Re-engagement in care of people living with HIV lost to follow-up after initiation of antiretroviral therapy in Mali: Who returns to care?

OBJECTIVES: We assessed cumulative incidence rates of and factors associated with re-engagement in HIV care for PLHIV lost to follow-up in Mali. METHODS: HIV-1-infected individuals lost to follow-up before 31/12/2013, ≥ 18 years old, who started ART from 2006 to 2012 at one of 16 care centres were considered. Loss to follow-up (LTFU) was defined as an interruption of ≥ 6 months during follow-up. The re-engagement in care in PLHIV lost to follow-up before 31/12/2013 was defined as having at least one clinical visit after LTFU. The cumulative incidence rates of re-engagement in care was estimated by Kaplan-Meier and its predictive factors were assessed using Cox models. Socio-demographic characteristics, clinical and immune status, period, region, centre expertise level, and distance from home at the start of ART plus a combined variable of duration of ART until LTFU and 12-month change in CD4 count were assessed. Multiple imputation was used to deal with missing data. RESULTS: We included 3,650 PLHIV lost to follow-up before December 2013, starting ART in nine outpatient clinics and seven hospitals (5+2 in Bamako and 4+5 in other regions): 35% male, median (IQR) age 35 (29-43), and duration of ART until LTFU 11 months (5-22). Among these PLHIV, 1,975 (54%) were definitively LTFU and 1,675 (46%) subsequently returned to care. The cumulative incidence rates of re-engagement in care rose from 39.0% at one year to 47.0% at three years after LTFU. Predictors of re-engagement in care were starting ART with WHO stage 1-2 and CD4 counts ≥ 200 cells/µL, being treated for ≥ 12 months with CD4 count gain ≥ 50 cells/µL, or being followed in Bamako. People followed at regional hospitals or outpatient clinics ≥ 5 km away, or being treated for ≥ 12 months with CD4 count gain < 50 cells/µL were less likely to return to care. CONCLUSIONS: Starting ART with a higher CD4 count, better gain in CD4 count, and being followed either in Bamako or close to home in the regions were associated with re-engagement in care.

Diagnostic Laboratories' Capacities and Preparedness for Emerging Viral Diseases in Guinea and Mali.

The 2014-2016 Ebola epidemic in Guinea highlighted the need for more extensive evaluation of laboratories diagnostic capacities and preparedness in anticipation of future emerging viral disease outbreaks. We developed a questionnaire to assess the diagnostic capacities and preparedness of the four major medical laboratories in Guinea and Mali that are responsible for the provision of Ebola, Lassa, and Dengue diagnostics. The questionnaire inquired about the current state and need for equipment and reagents and adequacy of equipment and training received. In Guinea, all three diagnostic laboratories have the capacity and are well-prepared to perform Ebola diagnostics, however, only two have the capacity and trained staff to diagnose Lassa and none are currently prepared to diagnose Dengue infection. In Mali, the University Clinical Research Center (UCRC) laboratory, which was in charge of Ebola diagnostics during the last epidemic, currently has the capacity and is prepared to diagnose Ebola, Lassa, and Dengue infections. Combined, Guinea and Mali appear to have complementary capacity and preparedness to diagnose these Category A Priority Pathogens. While, the equipment, reagents and training efforts should be maintained, the gap in Dengue diagnostic capability in Guinea should be addressed with further equipping and training of additional district laboratories to strengthen the public health response for all viral diseases in these high-risk, yet, low-resource settings.

Genetic barriers for integrase inhibitor drug resistance in HIV type-1 B and CRF02_AG subtypes.

BACKGROUND: HIV type-1 (HIV-1) integrase (IN) inhibitor resistance is the consequence of mutations that are selected in the viral IN gene targeted by antiretroviral drugs, such as raltegravir (RAL) and elvitegravir (EVG). The genetic barrier, defined as the number of viral mutations required to overcome the drug-selective pressure, is one of the important factors in the development of drug resistance. The genetic barrier for IN inhibitor resistance was compared between HIV-1 subtype B and HIV-1 subtype CRF02_AG, which is highly prevalent in West Africa and becoming more frequent in developed countries. METHODS: IN nucleotide sequences from 73 HIV-1 subtype B and 77 HIV-1 subtype CRF02_AG antiretroviral-naive patients were examined at 19 IN amino acid positions implicated in RAL and EVG resistance. RESULTS: The majority (14/19) of the studied positions showed a high degree of conservation of the predominant codon sequences leading to a similar genetic barrier between subtypes B and CRF02_AG. Nevertheless, at positions 140 and 151, the variability between subtypes affected the genetic barrier for the mutations G140C, G140S and V1511 with a higher genetic barrier being calculated for subtype CRF02_AG. CONCLUSIONS: The major IN mutations E92Q, Q148K/R/H, N155H and E157Q (implicated in the resistance of IN inhibitors RAL and EVG) are highly conserved between subtypes B and CRF02_AG and display a similar genetic barrier. However, subtype CRFO2_AG showed a higher genetic barrier to acquire mutations 6140S, 6140C and V1511 as compared with subtype B, which could play a role in the resistance to RAL and/or EV6.

Evaluation of Two HIV Rapid Diagnostic Tests in a Context of Strains' Genetic Diversity in Mali.

The rapid diagnostic tests used in most resource-limited countries offer little specificity in the differentiation of HIV-1, HIV-2, and HIV-1 + 2. World Health Organization (WHO) does periodically evaluate rapid tests in use in the South Countries. Despite the prequalification from WHO, it is necessary at local level to conduct comparative studies between the available tests. To do this in Mali, we conducted a cross-sectional study at the University Teaching Hospital Gabriel Touré and the Research and Training Center (SEREFO) of Bamako on 172 samples from retrospective and prospective studies. The goal of this project was to compare the following rapid tests: "HIV TRI-DOT" and OnSite HIV1/2 Ab Plus Combo Rapid Test for screening HIV-1 and HIV-2 to "ImmunoComb II BiSpot" (gold standard). The sensibility and specificity of "HIV TRI-DOT" for HIV-1 detection were 100% each [95% confidence interval (CI): 87.13-100 and 95.31-100]. Its performance for HIV-2 detection was 95.24% (95% CI: 84.21-98.68) (sensibility) and 100% (95% CI: 72.25-100) (specificity). The positive and negative predictive values were, respectively, 100% (95% CI: 91.24-100) and 83.33% (95% CI: 55.20-95.30). The sensibility and specificity of OnSite HIV1/2 Ab Plus Combo Rapid Test assay performance were 100% (95% CI: 87.13-100 and 95.31-100). Overall, OnSite HIV ½ Ab Combo Rapid Test proved to be a good test for warm countries and does not require refrigeration in these settings. Blood and its products can be used to perform the test, unlike "ImmunoComb II BiSpot" and "HIV TRI-DOT," which must be kept cold and cannot be done with whole blood.

Evolution of genetic diversity and drug resistance mutations in HIV-1 among untreated patients from Mali between 2005 and 2006.

OBJECTIVES: To describe HIV-1 variants circulating in Mali and to estimate the rate of transmission of HIV-1 drug resistance in 2006. PATIENTS AND METHODS: Viral reverse transcriptase (RT) and protease (PR) genes from 198 antiretroviral (ARV)-naive patients diagnosed HIV-1 positive in May 2006 in Bamako and Segou were sequenced. RESULTS: Although CRF02_AG was always the predominant HIV-1 subtype observed (72%), a higher genetic diversity than that in 2005 was observed. The overall prevalence of primary resistance is 11.5% in Mali in 2006, according to the 2007 IAS-USA list of mutations [nucleoside RT inhibitor (NRTI): 1.5%, non-NRTI (NNRTI): 9% and PI: 1%], and 2.5% (NRTI: 1%, NNRTI: 1.5% and PI: 0%), according to the Stanford list of mutations. There was no significant difference between 2005 and 2006 in the overall primary resistance prevalence or in the prevalence of mutations in the different ARV classes. Resistance mutations found in RT and PR genes are in agreement with the highly active antiretroviral therapy regimen available in Mali, except for V90I, V106I and A98G mutations which are associated with etravirine resistance, but polymorphic in non-B subtypes. CONCLUSIONS: HIV-1 genetic diversity seems increased in Mali, but the overall HIV-1 primary resistance prevalence remains low. This is consistent with the findings from other West African countries where prevalence rates are lower than 5%. However, considering the large scaling up of ARV use in this country, it is necessary to regularly monitor the development of primary resistance in Mali.

Very high prevalence of extended-spectrum beta-lactamase-producing Enterobacteriaceae in bacteriemic patients hospitalized in teaching hospitals in Bamako, Mali.

The worldwide dissemination of extended-spectrum beta-lactamase producing Enterobacteriaceae, (ESBL-E) and their subset producing carbapenemases (CPE), is alarming. Limited data on the prevalence of such strains in infections from patients from Sub-Saharan Africa are currently available. We determined, here, the prevalence of ESBL-E/CPE in bacteriemic patients in two teaching hospitals from Bamako (Mali), which are at the top of the health care pyramid in the country. During one year, all Enterobacteriaceae isolated from bloodstream infections (E-BSI), were collected from patients hospitalized at the Point G University Teaching Hospital and the pediatric units of Gabriel Touré University Teaching Hospital. Antibiotic susceptibility testing, enzyme characterization and strain relatedness were determined. A total of 77 patients had an E-BSI and as many as 48 (62.3%) were infected with an ESBL-E. ESBL-E BSI were associated with a previous hospitalization (OR 3.97 95% IC [1.32; 13.21]) and were more frequent in hospital-acquired episodes (OR 3.66 95% IC [1.07; 13.38]). Among the 82 isolated Enterobacteriaceae, 58.5% were ESBL-E (20/31 Escherichia coli, 20/26 Klebsiella pneumoniae and 8/15 Enterobacter cloacae). The remaining (5 Salmonella Enteritidis, 3 Morganella morganii 1 Proteus mirabilis and 1 Leclercia adecarboxylata) were ESBL negative. CTX-M-1 group enzymes were highly prevalent (89.6%) among ESBLs; the remaining ones being SHV. One E. coli produced an OXA-181 carbapenemase, which is the first CPE described in Mali. The analysis of ESBL-E relatedness suggested a high rate of cross transmission between patients. In conclusion, even if CPE are still rare for the moment, the high rate of ESBL-BSI and frequent cross transmission probably impose a high medical and economic burden to Malian hospitals.

Prevalence of ESBL-producing Enterobacteriaceae isolated from blood cultures in Mali.

INTRODUCTION: The increasing frequency of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae is becoming a serious public health concern. This study sought to determine ESBL frequency in Enterobacteriaceae isolated from patients' blood cultures in two university teaching hospitals of Bamako, Mali. METHODOLOGY: During a three-month period, the presence of Enterobacteriaceae from blood cultures of patients admitted to the university teaching hospitals of Bamako was evaluated. The microbial identifications were initially performed with an API 20E gallery and VITEK2 locally in Mali, and then confirmation in France was performed with a mass spectrometry MALDI-TOF in the bacteriology laboratory of the university teaching hospital of Bichat. Antibiotic susceptibility profiles were determined by the diffusion method as recommended by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). RESULTS: The isolated species were K. pneumoniae (14/40; 35.0%), E. coli (11/40; 27.5%), and E. cloacae (9/40; 22.5%). Of the strains isolated, 21/34 (61.8%) had an ESBL phenotype, including 10/14 (71.4%) K. pneumoniae, 8/11 (72.7%) E. coli, and 3/9 (33.3%) E. cloacae. Resistances associated with ESBL strains of K. pneumoniae, E. coli, and E. cloacae were as follows: gentamicin (10/10, 100%; 6/8, 75%; 2/3, 67%, respectively), amikacin (2/10, 20%; 0/8, 0%; 0/3, 0%, respectively), ofloxacin (8/10, 80%; 7/8, 87%; 3/3, 100%, respectively), and cotrimoxazole (10/10, 100%; 6/8, 75%; 3/3, 100%, respectively). CONCLUSION: Almost two-thirds (61.8%) of Enterobacteriaceae isolated from our blood cultures were ESBL producers. Only susceptibilities to carbapenems and to amikacin were fully conserved within the strains.