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1.
J Antimicrob Chemother ; 79(5): 1164-1168, 2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38546752

RESUMO

OBJECTIVES: Integrase strand transfer inhibitors (INSTIs) have been recently recommended as the preferred first-line option for antiretroviral treatment initiators in low- and middle-income countries (LMICs) in response to the growing circulation of resistant HIV to non-nucleoside reverse transcriptase inhibitors (NNRTIs). In this study, we estimated the frequency of pretreatment drug resistance (PDR) to INSTIs in West Africa and Southeast Asia. MATERIALS AND METHODS: Using samples collected from 2015 to 2016, and previously used to assessed PI, NRTI and NNRTI resistance, we generated HIV integrase sequences and identified relevant INSTI PDR mutations using the Stanford and ANRS algorithms. RESULTS: We generated 353 integrase sequences. INSTI PDR frequency was low, 1.1% (4/353) overall, ranging from 0% to 6.3% according to country. However, frequency of PDR to any drug class was very high, 17.9% (95% CI: 13.9%-22.3%), and mostly associated with a high level of NNRTI PDR, 9.7%, and a moderate level of NRTI PDR, 5.3%. CONCLUSIONS: Our results support the recent introduction of INSTIs in LMICs to improve treatment outcome in these settings, but also stress the need for effective actions to prevent uncontrolled emergence of drug resistance to this drug class.


Assuntos
Farmacorresistência Viral , Infecções por HIV , Inibidores de Integrase de HIV , Integrase de HIV , HIV-1 , Humanos , África Ocidental/epidemiologia , Sudeste Asiático/epidemiologia , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Infecções por HIV/epidemiologia , Integrase de HIV/genética , Inibidores de Integrase de HIV/farmacologia , Inibidores de Integrase de HIV/uso terapêutico , HIV-1/efeitos dos fármacos , HIV-1/genética , Mutação , Prevalência
2.
BMC Microbiol ; 24(1): 35, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38262985

RESUMO

BACKGROUND: Diarrhoea is a public health problem, especially in developing countries where it is the second leading cause of child mortality. In Low Income Countries like in Mali, self-medication and inappropriate use of antibiotics due to the scarcity of complementary diagnostic systems can lead to the development of multidrug-resistant bacteria causing diarrhoea. The objective of this work was to determine the microorganisms responsible for diarrhoea in children under 15 years of age and to characterize their sensitivity to a panel of antibiotics used in a peri-urban community in Mali. The study involved outpatient children visiting the Yirimadio Community Health Centre and diagnosed with diarrhoea. Stool samples from those patients were collected and analysed by conventional stools culture and the susceptibility to antibiotics of detected bacteria was determined by the disc diffusion method in an agar medium. RESULT: Overall, 554 patients were included. Children under the age of 3 years accounted for 88.8% (492 of 554) of our study population. Two bacterial species were isolated in this study, Escherichia coli 31.8% (176 of 554) and Salmonella 2.9% (16 of 554). In the 176, E. coli strains resistance to amoxicillin and to cotrimoxazole was seen in 93.8% (165 of 176) and 92.6% ( 163 of 176), respectively. The ESBL resistance phenotype accounted for 39,8% (70 of 176) of E. coli. Sixteen (16) strains of Salmonella were found, of which one strain (6.3%) was resistant to amoxicillin and to amoxicillin + clavulanic acid. Another one was resistant to chloramphenicol (6.3%). Two strains of Salmonella were resistant to cotrimoxazole (12.5%) and two others were resistant to cefoxitin (12.5%). CONCLUSIONS: The data suggest that E. coli is frequently involved in diarrhoea in children under 3 years of age in this peri-urban setting of Bamako, Mali, with a high rate of resistance to amoxicillin and cotrimoxazole, the most widely used antibiotics in the management of diarrhoea in this setting.


Assuntos
Antibacterianos , Saúde Pública , Criança , Humanos , Pré-Escolar , Mali , Combinação Trimetoprima e Sulfametoxazol , Escherichia coli , Farmacorresistência Bacteriana , Amoxicilina , Diarreia , Combinação Amoxicilina e Clavulanato de Potássio , Salmonella
3.
J Med Virol ; 94(9): 4554-4558, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35546445

RESUMO

In sub-Saharan Africa, the Human Herpesvirus 8 (HHV-8) is endemic but with disparities between regions and population studied. Although the virus remains mostly latent, there is some evidence that blood transfusion may represents one of the transmission way for this virus. Here, we evaluated HHV-8 seroprevalence among blood donors in Mali. This cross-sectional study recruited blood donors from the Blood Transfusion Center at Gabriel Touré Hospital, Bamako. Serum was used for the detection of latent HHV-8 immunoglobulin G directed against latent associated nuclear antigen 1 by an indirect immunofluorescence assay. Human immunodeficiency virus 1 (HIV-1), Hepatitis B Virus (HBV), HCV, and Treponema pallidum were also screened. HHV-8 seroprevalence was 10.4% in Malian blood donors. None of the sociodemographic characteristics were associated with HHV-8 infection, although there is a tendency of a higher HHV-8 seroprevalence among participants living in Bamako than those not living there. One individual had coinfection HHV-8/HBV, another HHV-8/HCV while another had HCV and T. pallidum. None has been tested positive for HIV infection. This intermediate seroprevalence in Malian blood donors suggests that the risk of HHV-8 transmission by transfusion should be considered. Further investigations are needed to assess impact of HHV-8 in polytransfused patients residing in an endemic area for this virus.


Assuntos
Infecções por HIV , Hepatite B , Hepatite C , Herpesvirus Humano 8 , Sífilis , Anticorpos Antivirais , Doadores de Sangue , Estudos Transversais , Vírus da Hepatite B , Hepatite C/epidemiologia , Humanos , Mali/epidemiologia , Estudos Soroepidemiológicos
4.
BMC Public Health ; 22(1): 1312, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35804333

RESUMO

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.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Complicações Infecciosas na Gravidez , Algoritmos , Fármacos Anti-HIV/uso terapêutico , Antirretrovirais/uso terapêutico , Feminino , Infecções por HIV/prevenção & controle , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Masculino , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Estudos Retrospectivos , Medição de Risco , Autorrelato , Organização Mundial da Saúde
5.
J Antimicrob Chemother ; 75(5): 1272-1279, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32073629

RESUMO

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.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Criança , Resistência a Medicamentos , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Mali/epidemiologia , Carga Viral
6.
J Antimicrob Chemother ; 74(2): 462-467, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30418575

RESUMO

Background: ART in the developing world has moved to a new era with the WHO recommendation to test and immediately treat HIV-positive individuals. A high frequency of pretreatment HIV drug resistance (PDR) can compromise ART efficacy. Our study presents updated estimates of PDR in seven countries from West Africa (Burkina Faso, Cameroon, Côte d'Ivoire, Mali and Togo) and Southeast Asia (Thailand and Vietnam). Methods: Eligible study participants were adult ART initiators, recruited from December 2015 to November 2016 in major ART clinics in each country. HIV drug resistance (HIVDR) tests were performed for all specimens and interpretation was done using the Stanford algorithm. Results: Overall, 1153 participants were recruited and 1020 nt sequences were generated. PDR frequency among all initiators was 15.9% (95% CI: 13.8%-18.3%) overall, ranging from 9.6% and 10.2% in Burkina Faso and Thailand, respectively, 14.7% in Vietnam, 15.4% in Mali, 16.5% in Côte d'Ivoire and 19.3% in Cameroon, to 24.6% in Togo. The prevalence of NNRTI resistance mutations was 12%; NRTI and PI PDR prevalences were 4% and 3%, respectively. Conclusions: Our study shows that in most countries PDR exceeded 10%, warranting the conduct of nationally representative surveys to confirm this trend. In the meantime, actions to prevent drug resistance, including transition from NNRTIs to more robust drug classes should be urgently implemented.


Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/epidemiologia , HIV-1/efeitos dos fármacos , Adulto , África Ocidental/epidemiologia , Fármacos Anti-HIV/sangue , Sudeste Asiático/epidemiologia , Feminino , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Carga Viral
7.
BMC Infect Dis ; 19(1): 1064, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31856758

RESUMO

BACKGROUND: HIV, HBV and HCV remain a global public health concern especially in Africa. Prevalence of these infections is changing and identification of risk factors associated with each infection in Mali is needed to improve medical care. METHODS: We conducted a cross-sectional study of all individuals donating blood (n = 8207) in 2018 to the blood bank at university hospital in Bamako, Mali, to assess prevalence and risks factors associated with HIV, HBV, HCV and syphilis infections. RESULTS: HIV-seroprevalence was 2.16% and significantly increased with age, being married and decreasing education level. In multivariate analysis, after adjustements with age, marital status and geographical setting, only education level was associated with HIV-infection (OR, 1.54 [95% CI, 1.15-2.07], p = 0.016). HBsAg prevalence was 14.78% and significantly increased with to be male gender. In multivariate analysis, adjusting for age, marital status and type of blood donation, education level (OR, 1.17 [95%CI, 1.05-1.31], p = 0.02) and male gender (OR, 1.37 [95%CI, 1.14-1.65], p = 0.005) were associated with HBV-infection. HCV-prevalence was 2.32% and significantly increased with living outside Bamako. In multivariate analysis, adjusting for gender, age and education level, living outside Bamako was associated with HCV-infection (OR, 1.83 [95% CI, 1.41-2.35], p < 0.001). Syphilis seroprevalence was very low (0.04%) with only 3 individuals infected. Contrary to a prior study, blood donation type was not, after adjustments, an independent risk factor for each infection. CONCLUSIONS: Overall, HIV and HBV infection was higher in individuals with a lower level of education, HBV infection was higher in men, and HCV infection was higher in people living outside of Bamako. Compared to studies performed in 1999, 2002 and 2007 in the same population, we found that HIV and HCV prevalence have decreased in the last two decades whereas HBV prevalence has remained stable. Our finding will help guide infection prevention and treatment programs in Mali.


Assuntos
Doadores de Sangue , Infecções por HIV/epidemiologia , Soroprevalência de HIV/tendências , HIV/imunologia , Hepacivirus/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Sífilis/epidemiologia , Treponema pallidum/imunologia , Adolescente , Adulto , Coinfecção , Estudos Transversais , Feminino , Hospitais Universitários , Humanos , Masculino , Mali , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Adulto Jovem
8.
J Antimicrob Chemother ; 72(4): 1147-1151, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28039275

RESUMO

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.


Assuntos
Anticorpos Anti-HIV/sangue , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/fisiologia , Transmissão Vertical de Doenças Infecciosas , Carga Viral , Adolescente , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Criança , Pré-Escolar , Estudos Transversais , Feminino , Infecções por HIV/transmissão , HIV-1/imunologia , Humanos , Masculino , Estudos Prospectivos , Viremia/imunologia , Adulto Jovem
9.
J Infect Dis ; 214(suppl 3): S164-S168, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27707892

RESUMO

Aware of the rapid spread of Ebola virus (EBOV) during the current West African epidemic, Mali took several proactive steps to rapidly identify cases within its borders. Under the Mali International Center for Excellence in Research program, a collaboration between the National Institute of Allergy and Infectious Diseases and the Malian Ministry of Higher Education and Scientific Research established a national EBOV diagnostic site at the University of Sciences, Techniques and Technologies of Bamako in the SEREFO Laboratory. Two separate introductions of EBOV occurred in Mali from neighboring Guinea, but both chains of transmission were quickly halted, and Mali was declared "Ebola free" on 18 January 2015 and has remained so since. The SEREFO Laboratory was instrumental in the success of Mali's Ebola response by providing timely and accurate diagnostics. As of today, the SEREFO Laboratory has tested 103 samples from 88 suspected cases, 10 of which were EBOV positive, since the Ebola diagnostics unit started in April 2014. The establishment of Ebola diagnostics in the SEREFO Laboratory, safety precautions, and diagnostics are described.


Assuntos
Serviços de Laboratório Clínico/organização & administração , Surtos de Doenças , Ebolavirus/isolamento & purificação , Doença pelo Vírus Ebola/diagnóstico , Ebolavirus/genética , Guiné , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/virologia , Humanos , Mali/epidemiologia , Manejo de Espécimes
10.
Clin Infect Dis ; 61 Suppl 4: S332-8, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26449949

RESUMO

BACKGROUND: In 2002, following establishment of a clinical microbiology laboratory in the government hospital that admits children with severe illnesses in Bamako, Mali, surveillance to identify pathogens causing invasive bacterial infections (septicemia, bacteremia, meningitis, etc) was initiated. METHODS: Parents/guardians of children aged <16 years admitted to l'Hôpital Gabriel Touré with high fever or clinical syndromes compatible with focal invasive bacterial disease were asked for consent to culture their child's blood/body fluid. Standard bacteriologic techniques speciated isolates; Salmonella serovars were determined. RESULTS: From July 2002 through June 2014, 687 nontyphoidal Salmonella (NTS) isolates were obtained from 667 children; 667 yielded a single serovar and 20 grew 2 Salmonella serovars, 1 being NTS. Four serovars accounted for 87% of the 687 NTS isolates, including Salmonella Enteritidis (n = 244 [35.5%]), Salmonella Typhimurium (n = 221 [32.2%]), I:4,[5],12:i:- (n = 42 [6.1%]), and Salmonella Dublin (n = 89 [13.0%]). Of 553 patients with invasive NTS from whom 1 of the 4 predominant serovars was isolated in pure culture, 448 (81.0%) were aged <5 years and case fatality was 20.3%; Salmonella Enteritidis case fatality (27.8%) was higher than for other serovars (P = .0009). NTS disease showed a seasonal peak following the rainy season and into the cool, dry season. Since 2010, Salmonella Enteritidis cases have risen and Salmonella Typhimurium fallen. CONCLUSIONS: NTS has become the predominant invasive pathogen as Haemophilus influenzae type b and pneumococcal vaccine use in Mali has diminished invasive disease due to those pathogens. The age distribution and limited serovars involved make control of NTS disease by vaccines epidemiologically feasible, if products under development prove safe and efficacious.


Assuntos
Infecções por Salmonella/epidemiologia , Infecções por Salmonella/microbiologia , Vacinas contra Salmonella , Salmonella enterica/isolamento & purificação , Adolescente , Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Criança , Pré-Escolar , Doenças Transmissíveis Emergentes , Descoberta de Drogas , Monitoramento Epidemiológico , Feminino , Humanos , Lactente , Masculino , Mali/epidemiologia , Infecções por Salmonella/mortalidade , Infecções por Salmonella/prevenção & controle , Salmonella enterica/classificação , Salmonella enteritidis/isolamento & purificação , Salmonella typhimurium/isolamento & purificação , Estações do Ano , Sorogrupo
11.
J Antimicrob Chemother ; 70(1): 130-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25270328

RESUMO

OBJECTIVES: The genetic barrier (defined as the number of genetic transitions/transversions needed to produce a resistance mutation) can differ between HIV-1 subtypes. The genetic barrier for the new attachment inhibitor BMS-626529 was evaluated in five HIV-1 subtypes. METHODS: Nine substitutions associated with BMS-626529 resistance at seven amino acid positions (116, 204, 375, 426, 434, 475 and 506) were analysed in 300 nucleotide sequences of the env gene encoding the gp120 protein from antiretroviral-naive patients (60 for each subtype and recombinant: B, C, D, CRF01_AE and CRF02_AG). RESULTS: Differently from the B subtype, some resistance mutations were found as natural polymorphisms in the C and D subtypes and the CRF02_AG and CRF01_AE recombinants for four positions of the env gene encoding the gp120 protein (375, 426, 434 and 475). The majority (five out of seven) of amino acid positions studied (116, 426, 434, 475 and 506) were relatively conserved (>63%) between the five HIV-1 subtypes, leading to a similar genetic barrier to mutations associated with resistance to BMS-626529. However, at positions 116 and 506 a minority of C and CRF02_AG subtypes had codons leading to a higher genetic barrier. Different predominant codons were observed at two out of seven positions (204 and 375) between the subtypes, with no effect on the calculated genetic barrier. However, for position 375, a minority of CRF02_AG sequences showed a lower genetic barrier to S375M/T resistance mutations. CONCLUSIONS: In non-B HIV-1 subtypes, four out of seven studied positions presented mutations implicated in BMS-626529 resistance. Despite great variability of the HIV-1 envelope, there was no major impact of polymorphisms on the genetic barrier to acquisition of BMS-626529 resistance.


Assuntos
Farmacorresistência Viral , Proteína gp120 do Envelope de HIV/genética , Inibidores da Fusão de HIV/farmacologia , HIV-1/efeitos dos fármacos , HIV-1/genética , Piperazinas/farmacologia , Triazóis/farmacologia , Substituição de Aminoácidos , Genótipo , Infecções por HIV/virologia , HIV-1/classificação , HIV-1/isolamento & purificação , Humanos , Mutação de Sentido Incorreto , Polimorfismo Genético
12.
J Antimicrob Chemother ; 69(3): 753-6, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24187041

RESUMO

OBJECTIVES: The relevance of low-level HIV DNA in patients who have undergone prolonged therapy is not well understood. The objective of this study was to determine factors that influence the establishment of low-level HIV DNA in long-term treated patients (excluding treatment since acute infection). METHODS: This was a cross-sectional study involving 243 patients receiving highly active antiretroviral therapy (HAART) for ≥6 months (median: 9 years of treatment) with plasma HIV RNA <50 copies/mL at the study timepoint, for whom total DNA measurements were performed. Patients treated since early acute infection or receiving cancer chemotherapeutic/immunosuppressive agents were excluded from the study. RESULTS: Overall, the median HIV DNA was 372 copies/10(6) peripheral blood mononuclear cells (PBMCs). Forty-seven patients had levels of HIV DNA below the limit of detection and 58 patients had low-level HIV DNA (<100 copies/10(6) PBMCs). In multivariate analysis, a low total HIV DNA in HAART-treated patients was clearly associated with a low HIV RNA pre-therapeutic viral load (P < 0.0001), regardless of the cut-off used. CONCLUSIONS: These results may be helpful to identify candidates for future trials aiming at a functional cure of HIV infection, since low total HIV DNA levels will most likely be a prerequisite of successful immunological control of HIV replication.


Assuntos
Terapia Antirretroviral de Alta Atividade/métodos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV/isolamento & purificação , Provírus/isolamento & purificação , Carga Viral , Adulto , Estudos Transversais , DNA Viral/sangue , Feminino , HIV/genética , Humanos , Leucócitos Mononucleares/virologia , Masculino , Pessoa de Meia-Idade , Provírus/genética , RNA Viral/sangue , Estudos Retrospectivos
13.
PLoS One ; 19(3): e0299082, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38446806

RESUMO

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.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Guiné/epidemiologia , SARS-CoV-2/genética , Pandemias , Estudos Retrospectivos , COVID-19/epidemiologia , África Ocidental/epidemiologia , Genômica
14.
J Virol Methods ; 330: 115026, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39233060

RESUMO

Due to shared routes of transmission, including sexual contact and vertical transmission, HIV-HBV co-infection is common, particularly in sub-Saharan Africa. Measurement of viral load (VL), for both HIV and HBV, plays a critical role for determining their infectious phase and monitoring response to antiviral therapy. Implementation of viral load testing in clinical settings is a significant challenge in resource-limited countries, notably because of cost and availability issues. We designed HIV and HBV primers for conserved regions of the HIV and HBV genomes that were specifically adapted to viral strains circulating in West Africa that are HIV-1 subtype CRF02AG and HBV genotype E. We first validated two monoplex qPCR assays for individual quantification and, then developed a multiplex qPCR for simultaneous quantification of both viruses. HIV RNA and HBV DNA amplification was performed in a single tube using a one-step reverse transcription-PCR reaction with primers and probes targeting both viruses. Performance characteristics such as the quantification range, sensitivity, and specificity of this multiplex qPCR assay were compared to reference qPCR tests for both HIV and HBV viral load quantification. The multiplex assay was validated using clinical samples from co- or mono-infected patients and gave comparable viral load quantification to the HIV and HBV reference test respectively. The multiplex qPCR demonstrated an overall sensitivity of 71.25 % [68.16-74.3] for HBV and 82 % [78.09-85.90] for HIV and an overall specificity of 100 % [94.95-100] for both viruses. Although the overall sensitivities of the HIV and HBV assays were lower than the commercial comparator assays, the sensitivity in the clinical decision range of >1000 copies/mL for HIV was 80 % [71.26-88.73] and >1000 IU/mL for HBV was 100 % [95.51-100] which indicates the test results can be used to guide treatment decisions. This in-house developed multiplex qPCR assay represents a useful diagnostic tool as it can be performed on affordable "open" real-time PCR platforms currently used for HIV or SARS-Cov-2 infection surveillance in Mali.

15.
Ticks Tick Borne Dis ; 15(1): 102276, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37967483

RESUMO

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.


Assuntos
Infecções por HIV , Vírus da Febre Hemorrágica da Crimeia-Congo , Febre Hemorrágica da Crimeia , Animais , Humanos , Feminino , Masculino , Estudos Soroepidemiológicos , Mali/epidemiologia , Doadores de Sangue , Estudos Retrospectivos , Anticorpos Antivirais , Gado , Infecções por HIV/epidemiologia
16.
Clin Microbiol Infect ; 30(8): 1067-1073, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38735369

RESUMO

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).


Assuntos
DNA Viral , Vírus da Hepatite B , Hepatite B , Humanos , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , DNA Viral/genética , África , Hepatite B/diagnóstico , Hepatite B/virologia , Ásia , Sensibilidade e Especificidade , Técnicas de Diagnóstico Molecular/métodos , Feminino , Carga Viral/métodos , Masculino , Reação em Cadeia da Polimerase/métodos , Adulto , Reação em Cadeia da Polimerase em Tempo Real/métodos , Pessoa de Meia-Idade
17.
Res Sq ; 2024 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-39281870

RESUMO

Background: People with Latent tuberculosis infection (LTBI) remain the reservoir of tuberculosis. One-third to 1/4 of the world's population is infected. Its reactivation is due to factors that disrupt the host's immune response. Recent findings showed that Schistosoma mansoni coinfection leads to a Th2/Th1 profile which results in an immune modulation that favors the escape of the Mycobacteria. Schistosoma mansoni may contribute to TB incidence in endemic regions. We aimed to investigate the co-infection rate and patient outcomes. Methods: A prospective cohort study was conducted between 2020-2022 at University Clinical Research Center (UCRC), including culture-confirmed active pulmonary TB patients and tested for Schistosoma mansoni in stools using Kato-Katz Technique. After descriptive analysis a logistic regression was performed to determine risk factors associated with TB and Schistosoma mansoni co-infection. Results: Data of 174 tuberculosis-confirmed patients, Kato-Katz tested were analyzed. Males represented 62.6%, mean age was 34.9 ± 13.8 years, 29.9% were smokers, alcohol consumption 13.8%, TB contact history 26.4%, HIV coinfection 11.5%, diabetes 6.3%, undernourished 55.7%. Schistosoma mansoni prevalence was 28.7%. The co-infection was associated with less lung cavitation [aOR = 0.24 [95% CI (0.06-0.85), p = 0.028], unfavorable treatment result [aOR = 2.95 (1.23-7.08), p = 0.015] and death [aOR = 3.43 (1.12-10.58), p = 0.032]. Conclusions: Despite Kato-Katz's low sensitivity, Schistosoma mansoni coinfection was found in one-third of the TB patients; 2.5-fold higher than that of HIV. The coinfection was associated with poor treatment results and death.

18.
Lancet HIV ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39059402

RESUMO

Analytical treatment interruption (ATI) is widely acknowledged as an essential component of studies to advance our understanding of HIV cure, but discussion has largely been focused on adults. To address this gap, we reviewed evidence related to the safety and utility of ATI in paediatric populations. Three randomised ATI trials using CD4 T-cell and clinical criteria to guide restart of antiretroviral therapy (ART) have been conducted. These trials found low risks associated with ATI in children, including reassuring findings pertaining to neurocognitive outcomes. Similar to adults treated during acute infection, infants treated early in life have shifts in virological and immunological parameters that increase their likelihood of achieving ART-free viral control. Early ART limits the size and diversity of the viral reservoir and shapes effective innate and HIV-specific humoral and cellular responses. Several cases of durable ART-free viral control in early treated children have been reported. We recommend that, where appropriate for the study question and where adequate monitoring is available, ATI should be integrated into ART-free viral control research in children living with HIV. Paediatric participants have the greatest likelihood of benefiting and potentially the most years to prospectively realise those benefits. Excluding children from ATI trials limits the evidence base and delays access to interventions.

19.
Res Sq ; 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37609282

RESUMO

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.

20.
Open J Epidemiol ; 13(1): 97-111, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36910425

RESUMO

Tuberculosis disease stands for the second leading cause of death worldwide after COVID-19, most active tuberculosis cases result from the reactivation of latent TB infection through impairment of immune response. Several factors are known to sustain that process. Schistosoma mansoni, a parasite of the helminth genus that possesses switching power from an immune profile type Th1 to Th2 that favors reactivation of latent TB bacteria. The aim of the study was to assess the prevalence of the co-infection between the two endemic infections. Systematic literature was contacted at the University Clinical Research Center at the University of Sciences, Techniques, and Technologies of Bamako in Mali. Original articles were included, and full texts were reviewed to assess the prevalence and better understand the immunological changes that occur during the co-infection. In total, 3530 original articles were retrieved through database search, 53 were included in the qualitative analysis, and data from 10 were included in the meta-analysis. Prevalence of the co-infection ranged from 4% to 34% in the literature. Most of the articles reported that immunity against infection with helminth parasite and more specifically Schistosoma mansoni infection enhances latent TB reactivation through Th1/Th2. In sum, the impact of Schistosoma mansoni co-infection with Mycobacterium tuberculosis is under-investigated. Understanding the role of this endemic tropical parasite as a contributing factor to TB epidemiology and burden could help integrate its elimination as one of the strategies to achieve the END-TB objectives by the year 2035.

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