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1.
PLOS Glob Public Health ; 4(5): e0003153, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38728356

RESUMEN

As of December 2022, Cameroon had observed a slight resurgence of COVID-19, raising concerns on genomic surveillance of related-SARS-CoV-2 variants under circulation. Following a laboratory-based survey, positive SARS-CoV-2 samples detected from December-2022 through March-2023 were processed for targeted sequencing at the Chantal BIYA International Reference Centre (CIRCB) in Yaoundé-Cameroon. From all positive cases detected, 13 were successfully sequenced (mean age 34 years, 70% female); the majority of the cases were unvaccinated (70%, 9/13) and symptomatic (92%, 12/13); all with flu-like symptoms (100%, 12/12). Following RT-PCR, the median cycle threshold was 22.23 [18-24] for the N gene; and 24.09 [20-26] for the ORF gene, underscoring high viral loads. Phylogenetic analysis of nucleotide sequences identified four major sub-variants in circulation, of which BA.5 (3/13), the recombinants BQ.1.1 (4/13), XBB.1 (4/13) and novel atypical variant of BA.4.6/XBB.1 (2/13). This snapshot surveillance indicates the introduction/emergence and circulation of new Omicron sub-variants, all accompanied by minor/mild symptoms. However, these new sub-variants and recombinants call for continuous genomic surveillance to prevent further resurgence of Covid-19 epidemiological wave.

2.
PLOS Glob Public Health ; 4(4): e0003030, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38573931

RESUMEN

As antiretroviral treatment (ART) coverage for people living with HIV (PLHIV) increases, HIV programmes require up-to-date information about evolving HIV risk behaviour and transmission risk, including those with low-level viremia (LLV; >50 to ≤1000 copies/mL), to guide prevention priorities. We aimed to assess differences in sexual risk behaviours, distribution of viral load (VL) and proportion of transmission across PLHIV subgroups. We analysed data from Population-based HIV Impact Assessment surveys in 14 sub-Saharan African countries during 2015-2019. We estimated adjusted prevalence ratios (aPR) of self-reported HIV high-risk behaviour (multiple partners and condomless sex) across cascade stages via generalised estimation equations. We modelled the proportions of transmission from each subgroup using relative self-reported sexual risk, a Hill function for transmission rate by VL, and proportions within cascade stages from surveys and UNAIDS country estimates for 2010-2020. Compared to PLHIV with undetectable VL (≤50 copies/mL), undiagnosed PLHIV (aPR women: 1.28 [95% CI: 1.08-1.52]; men: 1.61 [1.33-1.95]) and men diagnosed but untreated (2.06 [1.52-2.78]) were more likely to self-report high-risk sex. High-risk behaviour was not significantly associated with LLV. Mean VL was similar among undiagnosed, diagnosed but untreated, and on ART but non-suppressed sub-groups. Across surveys, undiagnosed and diagnosed but untreated contributed most to transmission (40-91% and 1-41%, respectively), with less than 1% from those with LLV. Between 2010 and 2020, the proportion of transmission from individuals on ART but non-suppressed increased. In settings with high ART coverage, effective HIV testing, ART linkage, and retention remain priorities to reduce HIV transmission. Persons with LLV are an increasing share of PLHIV but their contribution to HIV transmission was small. Improving suppression among PLHIV on ART with VL ≥1000 copies/mL will become increasingly important.

3.
Influenza Other Respir Viruses ; 18(4): e13267, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38532666

RESUMEN

BACKGROUND: Cameroon was among the most affected African countries during the first wave of the COVID-19 pandemic; however, the true prevalence of SARS-CoV-2 remains unknown. METHODS: From October to December 2020, we conducted a cross-sectional, age-stratified SARS-CoV-2 seroepidemiological survey at 30 purposively selected community-based sites across Cameroon's 10 regional capitals, sampling 10,000 individuals aged 5 years or older. We employed a parallel SARS-CoV-2 antibody testing algorithm (WANTAI ELISA and Abbott Architect) to improve both the positive predictive value and negative predictive value of seroprevalence. RESULTS: The overall weighted and adjusted seroprevalence of SARS-CoV-2 antibodies across the 10 urban capitals of Cameroon was 10.5% (95% CI: 9.1%-12.0%) among participants aged ≥5 years. Of the 9332 participants, 730 males (13.1%, 95% CI: 11.5%-14.9%) had SARS-CoV-2 antibodies compared to 293 females (8.0%, 95% CI: 6.8%-9.3%). Among those who reported a comorbidity at the time of testing, 15.8% (95% CI: 12.8%-19.4%) were seropositive. We estimated that over 2 million SARS-CoV-2 infections occurred in the 10 regional capitals of Cameroon between October and December 2020, compared to 21,160 cases officially reported at that time translating to one laboratory-confirmed case being reported for every 110 SARS-CoV-2 infections across the 10 urban capitals. CONCLUSION: This study's findings point to extensive and under-reported circulation of SARS-CoV-2 in Cameroon-an almost 100-fold more cases compared to the number of cases reported to the World Health Organization. This finding highlights the importance of conducting serosurveys, especially in settings where access to testing may be limited and to repeat such surveys as part of pandemic tracking.


Asunto(s)
COVID-19 , SARS-CoV-2 , Femenino , Masculino , Humanos , Camerún , Estudios Transversales , Pandemias , Estudios Seroepidemiológicos , Anticuerpos Antivirales
4.
J Acquir Immune Defic Syndr ; 95(4): 313-317, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38412045

RESUMEN

BACKGROUND: HIV testing is a critical step to accessing antiretroviral therapy (ART) because early diagnosis can facilitate earlier initiation of ART. This study presents aggregated data of individuals who self-reported being HIV-positive but subsequently tested HIV-negative during nationally representative Population-Based HIV Impact Assessment surveys conducted in 11 countries from 2015 to 2018. METHOD: Survey participants aged 15 years or older were interviewed by trained personnel using a standard questionnaire to determine HIV testing history and self-reported HIV status. Home-based HIV testing and counseling using rapid diagnostic tests with return of results were performed by survey staff according to the respective national HIV testing services algorithms on venous blood samples. Laboratory-based confirmatory HIV testing for all participants identified as HIV-positives and self-reported positives, irrespective of HIV testing results, was conducted and included Geenius HIV-1/2 and DNA polymerase chain reaction if Geenius was negative or indeterminate. RESULTS: Of the 16,630 participants who self-reported as HIV-positive, 16,432 (98.6%) were confirmed as HIV-positive and 198 (1.4%) were HIV-negative by subsequent laboratory-based testing. Participants who self-reported as HIV-positive but tested HIV-negative were significantly younger than 30 years, less likely to have received ART, and less likely to have received a CD4 test compared with participants who self-reported as HIV-positive with laboratory-confirmed infection. CONCLUSIONS: A small proportion of self-reported HIV-positive individuals could not be confirmed as positive, which could be due to initial misdiagnosis, deliberate wrong self-report, or misunderstanding of the questionnaire. As universal ART access is expanding, it is increasingly important to ensure quality of HIV testing and confirmation of HIV diagnosis before ART initiation.


Asunto(s)
Infecciones por VIH , Humanos , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Autoinforme , Encuestas y Cuestionarios , Errores Diagnósticos , África del Sur del Sahara/epidemiología
5.
Sci Rep ; 13(1): 21654, 2023 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-38066020

RESUMEN

While the SARS-CoV-2 dynamic has been described globally, there is a lack of data from Sub-Saharan Africa. We herein report the dynamics of SARS-CoV-2 lineages from March 2020 to March 2022 in Cameroon. Of the 760 whole-genome sequences successfully generated by the national genomic surveillance network, 74% were viral sub-lineages of origin and non-variants of concern, 15% Delta, 6% Omicron, 3% Alpha and 2% Beta variants. The pandemic was driven by SARS-CoV-2 lineages of origin in wave 1 (16 weeks, 2.3% CFR), the Alpha and Beta variants in wave 2 (21 weeks, 1.6% CFR), Delta variants in wave 3 (11 weeks, 2.0% CFR), and omicron variants in wave 4 (8 weeks, 0.73% CFR), with a declining trend over time (p = 0.01208). Even though SARS-CoV-2 heterogeneity did not seemingly contribute to the breadth of transmission, the viral lineages of origin and especially the Delta variants appeared as drivers of COVID-19 severity in Cameroon.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Camerún/epidemiología , COVID-19/epidemiología , Genómica
6.
Emerg Infect Dis ; 29(11): 2325-2334, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37877591

RESUMEN

Identifying persons who have newly acquired HIV infections is critical for characterizing the HIV epidemic direction. We analyzed pooled data from nationally representative Population-Based HIV Impact Assessment surveys conducted across 14 countries in Africa for recent infection risk factors. We included adults 15-49 years of age who had sex during the previous year and used a recent infection testing algorithm to distinguish recent from long-term infections. We collected risk factor information via participant interviews and assessed correlates of recent infection using multinomial logistic regression, incorporating each survey's complex sampling design. Compared with HIV-negative persons, persons with higher odds of recent HIV infection were women, were divorced/separated/widowed, had multiple recent sex partners, had a recent HIV-positive sex partner or one with unknown status, and lived in communities with higher HIV viremia prevalence. Prevention programs focusing on persons at higher risk for HIV and their sexual partners will contribute to reducing HIV incidence.


Asunto(s)
Infecciones por VIH , Humanos , Adulto , Femenino , Masculino , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , África/epidemiología , Factores de Riesgo , Parejas Sexuales , Recolección de Datos
7.
Microbiol Spectr ; 11(3): e0314822, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37071009

RESUMEN

Population-based HIV Impact Assessments (PHIAs) are national household (HH) surveys that provide HIV diagnosis and CD4 testing with an immediate return of results. Accurate CD4 results improve HIV-positive participants' clinical care and inform the effectiveness of HIV programs. Here, we present CD4 results from the PHIA surveys that were conducted in 11 countries in sub-Saharan Africa between 2015 and 2018. All of the HIV-positive participants and 2 to 5% of the HIV-negative participants were offered Pima CD4 (Abbott, IL, USA) point-of-care (POC) tests. The quality of the CD4 test was ensured by conducting instrument verification, comprehensive training, quality control, a review of testing errors and an analysis of unweighted CD4 data by HIV status, age, gender, and antiretroviral (ARV) treatment status. Overall, CD4 testing was completed for 23,085 (99.5%) of the 23,209 HIV-positive and 7,329 (2.7%) of the 270,741 negative participants in 11 surveys. The instrument error rate was 11.3% (range, 4.4% to 15.7%). The median CD4 values among HIV-positive and HIV-negative participants (aged 15+) were 468 cells/mm3 (interquartile range [IQR], 307 to 654) and 811 cells/mm3 (IQR, 647 to 1,013), respectively. Among the HIV-positive participants (aged 15+), those with detectable ARVs had higher CD4 values (508 cells/mm3) than those with undetectable ARVs (385.5 cells/mm3). Among the HIV-positive participants (aged 15+), 11.4% (2,528/22,253) had a CD4 value of less than 200 cells/mm3, and approximately half of them (1,225/2,528 = 48.5%) had detectable ARVs, whereas 51.5% (1,303/2,528) had no detectable ARVs (P < 0.0001). We successfully implemented high quality POC CD4 testing using Pima instruments. Our data come from nationally representative surveys in 11 countries and provide unique insights regarding the CD4 distribution among HIV-positive individuals as well as the baseline CD4 values among HIV-negative individuals. IMPORTANCE The manuscript describes CD4 levels among HIV-positive individuals and baseline CD4 levels among HIV-negative individuals from 11 sub-Saharan countries, thereby highlighting the importance of CD4 markers in the context of the HIV epidemic. Despite increased ARV access in each country, advanced HIV disease (CD4 < 200 cells/mm3) persists among approximately 11% of HIV-positive individuals. Therefore, it is important that our findings are shared with the scientific community to assist with similar implementations of point-of-care testing and to conduct a review of HIV programmatic gaps.


Asunto(s)
Infecciones por VIH , Sistemas de Atención de Punto , Humanos , Antirretrovirales/uso terapéutico , Recuento de Linfocito CD4 , VIH , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Pruebas en el Punto de Atención , Indicadores de Calidad de la Atención de Salud
8.
Emerg Infect Dis ; 28(13): S181-S190, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36502395

RESUMEN

The COVID-19 pandemic has highlighted the need for resilient health systems with the capacity to effectively detect and respond to disease outbreaks and ensure continuity of health service delivery. The pandemic has disproportionately affected resource-limited settings with inadequate health capacity, resulting in disruptions in health service delivery and worsened outcomes for key health indicators. As part of the US government's goal of ensuring health security, the US Centers for Disease Control and Prevention has used its scientific and technical expertise to build health capacity and address health threats globally. We describe how capacity developed through global health programs of the US Centers for Disease Control and Prevention in Cameroon was leveraged to respond to coronavirus disease and maintain health service delivery. The health system strengthening efforts in Cameroon can be applied in similar settings to ensure preparedness for future global public health threats and improve health outcomes.


Asunto(s)
COVID-19 , Pandemias , Estados Unidos/epidemiología , Humanos , Pandemias/prevención & control , Salud Global , COVID-19/prevención & control , Creación de Capacidad , Centers for Disease Control and Prevention, U.S.
9.
Emerg Infect Dis ; 28(13): S59-S68, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36502414

RESUMEN

The US President's Emergency Plan for AIDS Relief (PEPFAR) supports molecular HIV and tuberculosis diagnostic networks and information management systems in low- and middle-income countries. We describe how national programs leveraged these PEPFAR-supported laboratory resources for SARS-CoV-2 testing during the COVID-19 pandemic. We sent a spreadsheet template consisting of 46 indicators for assessing the use of PEPFAR-supported diagnostic networks for COVID-19 pandemic response activities during April 1, 2020, to March 31, 2021, to 27 PEPFAR-supported countries or regions. A total of 109 PEPFAR-supported centralized HIV viral load and early infant diagnosis laboratories and 138 decentralized HIV and TB sites reported performing SARS-CoV-2 testing in 16 countries. Together, these sites contributed to >3.4 million SARS-CoV-2 tests during the 1-year period. Our findings illustrate that PEPFAR-supported diagnostic networks provided a wide range of resources to respond to emergency COVID-19 diagnostic testing in 16 low- and middle-income countries.


Asunto(s)
COVID-19 , Infecciones por VIH , Humanos , Prueba de COVID-19 , Patología Molecular , Pandemias , SARS-CoV-2 , COVID-19/diagnóstico
10.
J Acquir Immune Defic Syndr ; 87(Suppl 1): S17-S27, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34166309

RESUMEN

BACKGROUND: Conducting HIV surveys in resource-limited settings is challenging because of logistics, limited availability of trained personnel, and complexity of testing. We described the procedures and systems deemed critical to ensure high-quality laboratory data in the population-based HIV impact assessments and large-scale household surveys. METHODS: Laboratory professionals were engaged in every stage of the surveys, including protocol development, site assessments, procurement, training, quality assurance, monitoring, analysis, and reporting writing. A tiered network of household, satellite laboratories, and central laboratories, accompanied with trainings, optimized process for blood specimen collection, storage, transport, and real-time monitoring of specimen quality, and test results at each level proved critical in maintaining specimen integrity and high-quality testing. A plausibility review of aggregate merged data was conducted to confirm associations between key variables as a final quality check for quality of laboratory results. RESULTS: Overall, we conducted a hands-on training for 3355 survey staff across 13 surveys, with 160-387 personnel trained per survey on biomarker processes. Extensive training and monitoring demonstrated that overall, 99% of specimens had adequate volume and 99.8% had no hemolysis, indicating high quality. We implemented quality control and proficiency testing for testing, resolved discrepancies, verified >300 Pima CD4 instruments, and monitored user errors. Aggregate data review for plausibility further confirmed the high quality of testing. CONCLUSIONS: Ongoing engagement of laboratory personnel to oversee processes at all levels of the surveys is critical for successful national surveys. High-quality population-based HIV impact assessments laboratory data ensured reliable results and demonstrated the impact of HIV programs in 13 countries.


Asunto(s)
Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , VIH-1 , Ensayos de Aptitud de Laboratorios/normas , Países en Desarrollo , Monitoreo Epidemiológico , Encuestas Epidemiológicas , Humanos , Personal de Laboratorio/educación , Personal de Laboratorio/normas , Control de Calidad
11.
J Acquir Immune Defic Syndr ; 87(Suppl 1): S73-S80, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34166315

RESUMEN

BACKGROUND: HIV-1 incidence calculation currently includes recency classification by HIV-1 incidence assay and unsuppressed viral load (VL ≥ 1000 copies/mL) in a recent infection testing algorithm (RITA). However, persons with recent classification not virally suppressed and taking antiretroviral (ARV) medication may be misclassified. SETTING: We used data from 13 African household surveys to describe the impact of an ARV-adjusted RITA on HIV-1 incidence estimates. METHODS: HIV-seropositive samples were tested for recency using the HIV-1 Limiting Antigen (LAg)-Avidity enzyme immunoassay, HIV-1 viral load, ARVs used in each country, and ARV drug resistance. LAg-recent result was defined as normalized optical density values ≤1.5. We compared HIV-1 incidence estimates using 2 RITA: RITA1: LAg-recent + VL ≥ 1000 copies/mL and RITA2: RITA1 + undetectable ARV. We explored RITA2 with self-reported ARV use and with clinical history. RESULTS: Overall, 357 adult HIV-positive participants were classified as having recent infection with RITA1. RITA2 reclassified 55 (15.4%) persons with detectable ARV as having long-term infection. Those with detectable ARV were significantly more likely to be aware of their HIV-positive status (84% vs. 10%) and had higher levels of drug resistance (74% vs. 26%) than those without detectable ARV. RITA2 incidence was lower than RITA1 incidence (range, 0%-30% decrease), resulting in decreased estimated new infections from 390,000 to 341,000 across the 13 countries. Incidence estimates were similar using detectable or self-reported ARV (R2 > 0.995). CONCLUSIONS: Including ARV in RITA2 improved the accuracy of HIV-1 incidence estimates by removing participants with likely long-term HIV infection.


Asunto(s)
Algoritmos , Monitoreo Epidemiológico , Infecciones por VIH/diagnóstico , VIH-1 , Adolescente , Adulto , Fármacos Anti-VIH/uso terapéutico , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Adulto Joven
12.
J Acquir Immune Defic Syndr ; 87(Suppl 1): S97-S106, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34166316

RESUMEN

BACKGROUND: Identifying men living with HIV in sub-Saharan Africa (SSA) is critical to end the epidemic. We describe the underlying factors of unawareness among men aged 15-59 years who ever tested for HIV in 13 SSA countries. METHODS: Using pooled data from the nationally representative Population-based HIV Impact Assessments, we fit a log-binomial regression model to identify characteristics related to HIV positivity among HIV-positive unaware and HIV-negative men ever tested for HIV. RESULTS: A total of 114,776 men were interviewed and tested for HIV; 4.4% were HIV-positive. Of those, 33.7% were unaware of their HIV-positive status, (range: 20.2%-58.7%, in Rwanda and Cote d'Ivoire). Most unaware men reported they had ever received an HIV test (63.0%). Age, region, marital status, and education were significantly associated with HIV positivity. Men who had HIV-positive sexual partners (adjusted prevalence ratio [aPR]: 5.73; confidence interval [95% CI]: 4.13 to 7.95) or sexual partners with unknown HIV status (aPR: 2.32; 95% CI: 1.89 to 2.84) were more likely to be HIV-positive unaware, as were men who tested more than 12 months compared with HIV-negative men who tested within 12 months before the interview (aPR: 1.58; 95% CI: 1.31 to 1.91). Tuberculosis diagnosis and not being circumcised were also associated with HIV positivity. CONCLUSION: Targeting subgroups of men at risk for infection who once tested negative could improve yield of testing programs. Interventions include improving partner testing, frequency of testing, outreach and educational strategies, and availability of HIV testing where men are accessing routine health services.


Asunto(s)
Monitoreo Epidemiológico , Infecciones por VIH/epidemiología , VIH-1 , Conocimientos, Actitudes y Práctica en Salud , Encuestas Epidemiológicas , Adolescente , Adulto , África del Sur del Sahara/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
13.
Afr J Lab Med ; 10(1): 1225, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34007816

RESUMEN

BACKGROUND: Competent leadership and management are imperative for delivering quality laboratory services; however, few laboratory managers receive job-specific training in organisational management and leadership. OBJECTIVE: To develop and evaluate participants' competencies in organisational leadership and management as measured through learner and laboratory quality improvement assessments. METHODS: This professional development programme employed a mentored, blended learning approach, utilising in-person didactic and online training, with the practical application of a capstone project in the laboratories. Programme impact was evaluated through a series of pre- and post-laboartory assessments using the Stepwise Laboratory Improvement Process Towards Accreditation checklist, as well as learner-competency assessments through online quizzes and discussions. RESULTS: From 2016 to 2018, 31 managers and quality officers from 16 individual laboratories graduated from the programme having completed capstone projects addressing areas in the entire laboratory testing process. Laboratories increased their compliance with the International Organization for Standardization 15189 standard and all but two laboratories significantly increased their accreditation scores. Two laboratories gained three stars, two laboratories gained two stars, and five laboratories gained one star. Five laboratories subsequently achieved International Organization for Standardization 15189 accreditation in 2019. CONCLUSION: This programme taught leadership theory to laboratory managers and allowed them to implement leadership and management practices in the laboratory setting. Programmes such as this complement existing laboratory quality management training programmes such as Strengthening Laboratory Management Toward Accreditation.

14.
Lancet Infect Dis ; 21(8): 1089-1096, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33773618

RESUMEN

BACKGROUND: Real-time PCR is recommended to detect SARS-CoV-2 infection. However, PCR availability is restricted in most countries. Rapid diagnostic tests are considered acceptable alternatives, but data are lacking on their performance. We assessed the performance of four antibody-based rapid diagnostic tests and one antigen-based rapid diagnostic test for detecting SARS-CoV-2 infection in the community in Cameroon. METHODS: In this clinical, prospective, diagnostic accuracy study, we enrolled individuals aged at least 21 years who were either symptomatic and suspected of having COVID-19 or asymptomatic and presented for screening. We tested peripheral blood for SARS-CoV-2 antibodies using the Innovita (Biological Technology; Beijing, China), Wondfo (Guangzhou Wondfo Biotech; Guangzhou, China), SD Biosensor (SD Biosensor; Gyeonggi-do, South Korea), and Runkun tests (Runkun Pharmaceutical; Hunan, China), and nasopharyngeal swabs for SARS-CoV-2 antigen using the SD Biosensor test. Antigen rapid diagnostic tests were compared with Abbott PCR testing (Abbott; Abbott Park, IL, USA), and antibody rapid diagnostic tests were compared with Biomerieux immunoassays (Biomerieux; Marcy l'Etoile, France). We retrospectively tested two diagnostic algorithms that incorporated rapid diagnostic tests for symptomatic and asymptomatic patients using simulation modelling. FINDINGS: 1195 participants were enrolled in the study. 347 (29%) tested SARS-CoV-2 PCR-positive, 223 (19%) rapid diagnostic test antigen-positive, and 478 (40%) rapid diagnostic test antibody-positive. Antigen-based rapid diagnostic test sensitivity was 80·0% (95% CI 71·0-88·0) in the first 7 days after symptom onset, but antibody-based rapid diagnostic tests had only 26·8% sensitivity (18·3-36·8). Antibody rapid diagnostic test sensitivity increased to 76·4% (70·1-82·0) 14 days after symptom onset. Among asymptomatic participants, the sensitivity of antigen-based and antibody-based rapid diagnostic tests were 37·0% (27·0-48·0) and 50·7% (42·2-59·1), respectively. Cohen's κ showed substantial agreement between Wondfo antibody rapid diagnostic test and gold-standard ELISA (κ=0·76; sensitivity 0·98) and between Biosensor and ELISA (κ=0·60; sensitivity 0·94). Innovita (κ=0·47; sensitivity 0·93) and Runkun (κ=0·43; sensitivity 0·76) showed moderate agreement. An antigen-based retrospective algorithm applied to symptomatic patients showed 94·0% sensitivity and 91·0% specificity in the first 7 days after symptom onset. For asymptomatic participants, the algorithm showed a sensitivity of 34% (95% CI 23·0-44·0) and a specificity of 92·0% (88·0-96·0). INTERPRETATION: Rapid diagnostic tests had good overall sensitivity for diagnosing SARS-CoV-2 infection. Rapid diagnostic tests could be incorporated into efficient testing algorithms as an alternative to PCR to decrease diagnostic delays and onward viral transmission. FUNDING: Médecins Sans Frontières WACA and Médecins Sans Frontières OCG. TRANSLATIONS: For the French and Spanish translations of the abstract see Supplementary Materials section.


Asunto(s)
Anticuerpos Antivirales/sangre , Antígenos Virales/análisis , Infecciones Asintomáticas , Prueba Serológica para COVID-19 , COVID-19/diagnóstico , SARS-CoV-2/inmunología , Estudios de Factibilidad , Humanos , Estudios Prospectivos , Sensibilidad y Especificidad
15.
PLoS One ; 15(7): e0236501, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32706823

RESUMEN

OBJECTIVES: The main objectives of the study are to estimate HIV prevalence, active syphilis prevalence, and correlates of co-infection with HIV in Zambia, among recently sexually active individuals aged 15 to 59 years old. METHODS: We used data from the 2016 Zambia Population-based HIV Impact Assessment (ZAMPHIA), a national household survey that included biomarker testing for HIV and syphilis. Chembio DPP® Syphilis Screen and Confirm Assay was used to distinguish between active and older syphilis infections. This is the first time Chembio DPP® has been used in a national survey. Log-binominal modelling was utilized to understand the risk of acquiring HIV/active syphilis co-infection using select socio-demographic and sexual behavior variables. Multivariable analysis compared those with co-infection and those with no infection. All reported results account for the complex survey design and are weighted. RESULTS: A total of 19,114 individuals aged 15-59 years responded to the individual interview and had a valid syphilis and/or HIV test. The prevalence for those sexually active in the 12 months preceding ZAMPHIA 2016 was 3.5% and 13% for active syphilis and HIV, respectively. The prevalence of HIV/active syphilis co-infection was 1.5%. Factors associated with higher prevalence of co-infection versus no infection among females included, but were not limited to, those living in urban areas (adjusted prevalence ratio (aPR) = 3.0, 95% CI = 1.8, 4.8), those had sexual intercourse before age 15 years (aPR = 1.8, 95% CI = 1.1, 2.9), and those who had two or more sexual partners in the 12 months preceding the survey (aPR = 2.7, 95% CI = 1.6, 4.7). CONCLUSION: These findings show high prevalence for both mono-infection with HIV and syphilis, as well as co-infection with HIV/active syphilis in Zambia. There is a need for better screening and partner services, particularly among those engaging in high-risk sexual behaviors (e.g., engaging in transactional sex).


Asunto(s)
Coinfección/epidemiología , Infecciones por VIH/epidemiología , Sífilis/epidemiología , Adolescente , Adulto , Estudios Transversales , Femenino , VIH-1 , Conductas de Riesgo para la Salud , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Encuestas y Cuestionarios , Sexo Inseguro , Adulto Joven , Zambia/epidemiología
16.
J Int AIDS Soc ; 20 Suppl 72017 11.
Artículo en Inglés | MEDLINE | ID: mdl-29171193

RESUMEN

INTRODUCTION: Logistical complexities of returning laboratory test results to participants have precluded most population-based HIV surveys conducted in sub-Saharan Africa from doing so. For HIV positive participants, this presents a missed opportunity for engagement into clinical care and improvement in health outcomes. The Population-based HIV Impact Assessment (PHIA) surveys, which measure HIV incidence and the prevalence of viral load (VL) suppression in selected African countries, are returning VL results to health facilities specified by each HIV positive participant within eight weeks of collection. We describe the performance of the specimen and data management systems used to return VL results to PHIA participants in Zimbabwe, Malawi and Zambia. METHODS: Consenting participants underwent home-based counseling and HIV rapid testing as per national testing guidelines; all confirmed HIV positive participants had VL measured at a central laboratory on either the Roche CAP/CTM or Abbott m2000 platform. On a bi-weekly basis, a dedicated data management team produced logs linking the VL test result with the participants' contact information and preferred health facility; project staff sent test results confidentially via project drivers, national courier systems, or electronically through an adapted short message service (SMS). Participants who provided cell phone numbers received SMS or phone call alerts regarding availability of VL results. RESULTS AND DISCUSSION: From 29,634 households across the three countries, 78,090 total participants 0 to 64 years in Zimbabwe and Malawi and 0 to 59 years in Zambia underwent blood draw and HIV testing. Of the 8391 total HIV positive participants identified, 8313 (99%) had VL tests performed and 8245 (99%) of these were returned to the selected health facilities. Of the 5979 VL results returned in Zimbabwe and Zambia, 85% were returned within the eight-week goal with a median turnaround time of 48 days (IQR: 33 to 61). In Malawi, where exact return dates were unavailable all 2266 returnable results reached the health facilities by 11 weeks. CONCLUSIONS: The first three PHIA surveys returned the vast majority of VL results to each HIV positive participant's preferred health facility within the eight-week target. Even in the absence of national VL monitoring systems, a system to return VL results from a population-based survey is feasible, but it requires developing laboratory and data management systems and dedicated staff. These are likely important requirements to strengthen return of results systems in routine clinical care.


Asunto(s)
Infecciones por VIH/virología , Revelación de la Verdad , Carga Viral , Adolescente , Adulto , África del Sur del Sahara , Teléfono Celular , Niño , Preescolar , Consejo , Femenino , VIH-1 , Instituciones de Salud , Humanos , Lactante , Recién Nacido , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Relaciones Médico-Paciente , Encuestas y Cuestionarios , Envío de Mensajes de Texto , Adulto Joven
17.
AIDS ; 31(13): 1885-1889, 2017 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-28746086

RESUMEN

OBJECTIVES: The objectives of this study were to determine HIV drug resistance (HIVDR) prevalence in Zambian infants upon diagnosis, and to determine how changing prevention of mother-to-child transmission (PMTCT) drug regimens affect drug resistance. DESIGN: Dried blood spot (DBS) samples from infants in the Lusaka District of Zambia, obtained during routine diagnostic screening, were collected during four different years representing three different PMTCT drug treatment regimens. METHODS: DNA extracted from dried blood spot samples was used to sequence a 1493 bp region of the reverse transcriptase gene. Sequences were analyzed via the Stanford HIVDRdatabase (http://hivdb.standford.edu) to screen for resistance mutations. RESULTS: HIVDR in infants increased from 21.5 in 2007/2009 to 40.2% in 2014. Nonnucleoside reverse transcriptase inhibitor resistance increased steadily over the sampling period, whereas nucleoside reverse transcriptase inhibitor resistance and dual class resistance both increased more than threefold in 2014. Analysis of drug resistance scores in each group revealed increasing strength of resistance over time. In 2014, children with reported PMTCT exposure, defined as infant prophylaxis and/or maternal treatment, showed a higher prevalence and strength of resistance compared to those with no reported exposure. CONCLUSION: HIVDR is on the rise in Zambia and presents a serious problem for the successful lifelong treatment of HIV-infected children. PMTCT affects both the prevalence and strength of resistance and further research is needed to determine how to mitigate its role leading to resistance.


Asunto(s)
Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Farmacorresistencia Viral , Infecciones por VIH/prevención & control , Infecciones por VIH/virología , VIH/efectos de los fármacos , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Sangre/virología , Preescolar , Estudios de Cohortes , Utilización de Medicamentos , Femenino , Genotipo , VIH/enzimología , VIH/genética , Infecciones por VIH/epidemiología , Transcriptasa Inversa del VIH/genética , Humanos , Lactante , Recién Nacido , Masculino , Mutación Missense , Embarazo , Prevalencia , Análisis de Secuencia de ADN , Zambia/epidemiología
18.
MMWR Morb Mortal Wkly Rep ; 65(46): 1285-1290, 2016 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-27880749

RESUMEN

Pediatric human immunodeficiency virus (HIV) infection remains an important public health issue in resource-limited settings. In 2015, 1.4 million children aged <15 years were estimated to be living with HIV (including 170,000 infants born in 2015), with the vast majority living in sub-Saharan Africa (1). In 2014, 150,000 children died from HIV-related causes worldwide (2). Access to timely HIV diagnosis and treatment for HIV-infected infants reduces HIV-associated mortality, which is approximately 50% by age 2 years without treatment (3). Since 2011, the annual number of HIV-infected children has declined by 50%. Despite this gain, in 2014, only 42% of HIV-exposed infants received a diagnostic test for HIV (2), and in 2015, only 51% of children living with HIV received antiretroviral therapy (1). Access to services for early infant diagnosis of HIV (which includes access to testing for HIV-exposed infants and clinical diagnosis of HIV-infected infants) is critical for reducing HIV-associated mortality in children aged <15 years. Using data collected from seven countries supported by the U.S. President's Emergency Plan for AIDS Relief (PEPFAR), progress in the provision of HIV testing services for early infant diagnosis was assessed. During 2011-2015, the total number of HIV diagnostic tests performed among HIV-exposed infants within 6 weeks after birth (tests for early infant diagnosis of HIV), as recommended by the World Health Organization (WHO) increased in all seven countries (Cote d'Ivoire, the Democratic Republic of the Congo, Haiti, Malawi, South Africa, Uganda, and Zambia); however, in 2015, the rate of testing for early infant diagnosis among HIV-exposed infants was <50% in five countries. HIV positivity among those tested declined in all seven countries, with three countries (Cote d'Ivoire, the Democratic Republic of the Congo, and Uganda) reporting >50% decline. The most common challenges for access to testing for early infant diagnosis included difficulties in specimen transport, long turnaround time between specimen collection and receipt of results, and limitations in supply chain management. Further reductions in HIV mortality in children can be achieved through continued expansion and improvement of services for early infant diagnosis in PEPFAR-supported countries, including initiatives targeted to reach HIV-exposed infants, ensure access to programs for early infant diagnosis of HIV, and facilitate prompt linkage to treatment for children diagnosed with HIV infection.


Asunto(s)
Diagnóstico Precoz , Infecciones por VIH/diagnóstico , Tamizaje Masivo/estadística & datos numéricos , África del Sur del Sahara , Región del Caribe , Femenino , Infecciones por VIH/transmisión , Humanos , Lactante , Transmisión Vertical de Enfermedad Infecciosa , Embarazo
19.
J Mol Biol ; 428(11): 2275-2288, 2016 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-27075671

RESUMEN

A key contributor to HIV-1 genetic variation is reverse transcriptase errors. Some mutations result because reverse transcriptase (RT) lacks 3' to 5' proofreading exonuclease and can extend mismatches. However, RT also excises terminal nucleotides to a limited extent, and this activity contributes to AZT resistance. Because HIV-1 mismatch resolution has been studied in vitro but only indirectly during replication, we developed a novel system to study mismatched base pair resolution during HIV-1 replication in cultured cells using vectors that force template switching at defined locations. These vectors generated mismatched reverse transcription intermediates, with proviral products diagnostic of mismatch resolution mechanisms. Outcomes for wild-type (WT) RT and an AZT-resistant (AZT(R)) RT containing a thymidine analog mutation set-D67N, K70R, D215F, and K219Q-were compared. AZT(R) RT did not excise terminal nucleotides more frequently than WT, and for the majority of tested mismatches, both WT and AZT(R) RTs extended mismatches in more than 90% of proviruses. However, striking enzyme-specific differences were observed for one mispair, with WT RT preferentially resolving dC-rC pairs either by excising the mismatched base or switching templates prematurely, while AZT(R) RT primarily misaligned the primer strand, causing deletions via dislocation mutagenesis. Overall, the results confirmed HIV-1 RT's high capacity for mismatch extension during virus replication and revealed dramatic differences in aberrant intermediate resolution repertoires between WT and AZT(R) RTs on one mismatched replication intermediate. Correlating mismatch extension frequencies observed here with reported viral mutation rates suggests a complex interplay of nucleotide discrimination and mismatch extension drives HIV-1 mutagenesis.


Asunto(s)
Reparación de la Incompatibilidad de ADN/genética , ADN Viral/genética , Farmacorresistencia Viral/genética , Transcriptasa Inversa del VIH/metabolismo , VIH-1/genética , Nucleótidos/genética , Replicación Viral/genética , Fármacos Anti-VIH/farmacología , Reparación de la Incompatibilidad de ADN/efectos de los fármacos , Cartilla de ADN/genética , Replicación del ADN/efectos de los fármacos , Replicación del ADN/genética , VIH-1/efectos de los fármacos , Humanos , Mutación/efectos de los fármacos , Mutación/genética , Inhibidores de la Transcriptasa Inversa/farmacología , Moldes Genéticos , Replicación Viral/efectos de los fármacos
20.
Emerg Infect Dis ; 21(11): 2022-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26488116

RESUMEN

The largest recorded Ebola virus disease epidemic began in March 2014; as of July 2015, it continued in 3 principally affected countries: Guinea, Liberia, and Sierra Leone. Control efforts include contact tracing to expedite identification of the virus in suspect case-patients. We examined contact tracing activities during September 20-December 31, 2014, in 2 prefectures of Guinea using national and local data about case-patients and their contacts. Results show less than one third of case-patients (28.3% and 31.1%) were registered as contacts before case identification; approximately two thirds (61.1% and 67.7%) had no registered contacts. Time to isolation of suspected case-patients was not immediate (median 5 and 3 days for Kindia and Faranah, respectively), and secondary attack rates varied by relationships of persons who had contact with the source case-patient and the type of case-patient to which a contact was exposed. More complete contact tracing efforts are needed to augment control of this epidemic.


Asunto(s)
Trazado de Contacto/métodos , Brotes de Enfermedades/prevención & control , Ebolavirus/patogenicidad , Fiebre Hemorrágica Ebola/epidemiología , Salud Pública/métodos , Adulto , Trazado de Contacto/estadística & datos numéricos , Femenino , Guinea/epidemiología , Fiebre Hemorrágica Ebola/transmisión , Humanos , Masculino , Persona de Mediana Edad
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