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1.
PLoS One ; 19(1): e0294860, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38166089

RESUMO

INTRODUCTION: Despite declines in new HIV diagnoses both globally and in Kenya, parts of Western Kenya still report high HIV prevalence and incidence. We evaluated HIV prevalence to inform the development of policies for strategic and targeted HIV prevention interventions. METHODS: Adult participants aged 18-35 years were recruited in Kisumu County and screened for HIV for a prospective HIV incidence cohort. Questionnaires assessed HIV-associated risk behaviors. Participants who tested positive for HIV were disaggregated into groups based on prior knowledge of their HIV status: previously-diagnosed and newly-diagnosed. In separate analyses by prior knowledge, robust Poisson regression was used to estimate prevalence ratios (PRs) and 95% confidence intervals (CIs) for factors potentially associated with a positive HIV test in each group, as compared to participants without HIV. RESULTS: Of 1059 participants tested for HIV, 196 (18.5%) had a positive HIV test. Among PLWH, 78 (39.8%) were newly diagnosed with HIV at screening. After adjusting for other variables, previously-diagnosed HIV was more common among females than males (PR 2.70, 95%CI 1.69-4.28), but there was no observed sex difference in newly-diagnosed HIV prevalence (PR 1.05, 95%CI 0.65-1.69). Previously-diagnosed HIV was also more common among people reporting consistent use of condoms with primary sexual partners as compared to inconsistent condom use (PR 3.19, 95%CI 2.09-4.86), but newly-diagnosed HIV was not associated with such a difference between consistent and inconsistent condom use (PR 0.73, 95%CI 0.25-2.10). CONCLUSION: Prevalence of newly-diagnosed HIV was high, at approximately 8% of participants, and not statistically different between genders, highlighting the need for improved HIV case finding regardless of sex. The higher prevalence of previously-diagnosed HIV in female participants may reflect higher rates of HIV testing through more encounters with the healthcare system. Higher prevalence of consistent condom use amongst those previously-diagnosed suggests behavioral change to reduce HIV transmission, a potential benefit of policies to facilitate earlier HIV diagnosis.


Assuntos
Infecções por HIV , Adulto , Humanos , Feminino , Masculino , Estudos Prospectivos , Quênia/epidemiologia , Prevalência , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Sexo Seguro , Parceiros Sexuais , Preservativos
2.
AIDS ; 37(4): 625-635, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36398743

RESUMO

OBJECTIVE: Cervical cancer is a common preventable cancer among African women living with HIV (WLWH). Molecular diagnostics for high-risk human papillomavirus (HR-HPV) genotypes are standard components of cervical cancer screening in resource-rich countries but not in resource-limited settings. We evaluated HR-HPV genotypes among women with and without HIV in four African countries to inform cervical cancer preventive strategies. METHODS: The African Cohort Study (AFRICOS) enrolled participants with and without HIV at 12 clinics in Tanzania, Kenya, Uganda, and Nigeria. Cervical cytobrush specimens from women were genotyped for 14 HR-HPV types using the multiplex Seegene Anyplex real-time PCR assay. Robust Poisson regression was used to estimate relative risks (RRs) and 95% confidence intervals (CIs) for factors associated with HR-HPV in WLWH. RESULTS: From January 2015 to March 2020, 868 WLWH and 134 women living without HIV (WLWoH) were tested for HR-HPV with prevalence of 50.9 and 38.1%, respectively ( P  = 0.007). Among WLWH, 844 (97.4%) were antiretroviral therapy (ART)-experienced and 772 (89.7%) virally suppressed 1000 copies/ml or less. The most frequent HR-HPV types among WLWH were HPV-16 (13.5%), HPV-52 (9.5%), and HPV-35 (9.3%). HR-HPV infection was more common among Tanzanian WLWH (adjusted RR: 1.23, 95% CI 1.05-1.44, P  = 0.012). Also, WLWH with CD4 + T cells of less than 200 cell/µl had 1.51-fold increased risk of having HR-HPV (95% CI 1.23-1.86, P  < 0.001). CONCLUSION: HR-HPV was common in WLWH in four African countries, particularly among women with low CD4 + cell count. Scale up of HPV vaccines and development of vaccines with broader activity against less common HR-HPV types may improve cervical cancer prevention in Africa.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Infecções por HIV/complicações , Neoplasias do Colo do Útero/diagnóstico , Fatores de Risco , Papillomavirus Humano , Estudos de Coortes , Infecções por Papillomavirus/complicações , Detecção Precoce de Câncer , Quênia , Genótipo , Papillomaviridae/genética , Prevalência
3.
BMC Immunol ; 23(1): 12, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35287587

RESUMO

BACKGROUND: Human immunodeficiency virus type 1 (HIV-1) causes impairment of T and B cell responses, which begins during the acute phase of infection and is not completely restored by antiretroviral treatment. Regulatory T cell (Tregs) can improve overall disease outcome by controlling chronic inflammation but may also suppress beneficial HIV-1 specific immune responses. We aimed to analyze the profile of Tregs and their correlation with the status of T cells activation, the expression of IL-2 and IFNγ and the profile of HIV-1 specific antibodies response in Mozambican people living chronically with HIV-1 (PLWH-C). RESULTS: In PLWH-C, the proportion of total Tregs was positively correlated with the proportion of IL-2+CD4 T cells (r = 0.647; p = 0.032) and IL-2+IFNγ+CD8 T cells (r = 0.551; p = 0.014), while the proportions of Helios+Tregs correlated inversely with levels of IL-2+CD8 T cells (r = - 0.541; p = 0.017). Overall, PLWH-C, with (82%) or without virologic suppression (64%), were seronegative for at least HIV-1 p31, gp160 or p24, and the breadth of antibody responses was positively correlated with proportions of CD38+HLA-DR+CD8 T cells (r = 0.620; p = 0.012), viral load (r = 0.452; p = 0.040) and inversely with absolute CD4 T cells count (r = - 0.481; p = 0.027). Analysis of all individuals living HIV-1 showed that the breadth of HIV-1 antibody responses was inversely correlated with the proportion of Helios+Tregs (r = - 0.45; p = 0.02). CONCLUSION: Among Mozambican people living with HIV-1, seronegativity to some HIV-1 proteins is common, particularly in virologically suppressed individuals. Furthermore, lower diversity of HIV-specific antibodies is correlated to lower immune activation, lower viral replication and higher CD4 counts, in PLWH-C. Elevation in the proportion of Helios+Tregs is related to a reduction of CD8 T expressing intracellular IL-2, in PLWH-C, but may contribute to impairment of B cell function.


Assuntos
Infecções por HIV , HIV-1 , Diversidade de Anticorpos , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Humanos , Interleucina-2/metabolismo , Ativação Linfocitária , Moçambique , Linfócitos T Reguladores
4.
AIDS ; 35(14): 2401-2404, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34482354

RESUMO

Among 582 participants in Western Kenya who were retrospectively tested from January through March 2020, 19 (3.3%) had detectable SARS-CoV-2 antibodies. The prevalence of detectable SARS-CoV-2 antibodies was similar between participants with and without HIV (3.1% vs. 4%, P = 0.68). One participant reported a cough in the preceding week but others denied symptoms. These may represent cross-reactivity or asymptomatic infections that predated the first reported COVID-19 cases in Kenya.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/diagnóstico , Infecções por HIV , Infecções por HIV/epidemiologia , Humanos , Quênia/epidemiologia , Prevalência , Estudos Retrospectivos , SARS-CoV-2/imunologia
5.
BMC Infect Dis ; 21(1): 937, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34503469

RESUMO

BACKGROUND: Malaria and schistosomiasis present considerable disease burden in tropical and sub-tropical areas and severity is worsened by co-infections in areas where both diseases are endemic. Although pathogenesis of these infections separately is well studied, there is limited information on the pathogenic disease mechanisms and clinical disease outcomes in co-infections. In this study, we investigated the prevalence of malaria and schistosomiasis co-infections, and the hematologic and blood chemistry abnormalities in asymptomatic adults in a rural fishing community in western Kenya. METHODS: This sub-study used samples and data collected at enrollment from a prospective observational cohort study (RV393) conducted in Kisumu County, Kenya. The presence of malaria parasites was determined using microscopy and real-time-PCR, and schistosomiasis infection by urine antigen analysis (CCA). Hematological analysis and blood chemistries were performed using standard methods. Statistical analyses were performed to compare demographic and infection data distribution, and hematologic and blood chemistry parameters based on different groups of infection categories. Clinically relevant hematologic conditions were analyzed using general linear and multivariable Poisson regression models. RESULTS: From February 2017 to May 2018, we enrolled 671 participants. The prevalence of asymptomatic Plasmodium falciparum was 28.2% (157/556) and schistosomiasis 41.2% (229/562), with 18.0% (100/556) of participants co-infected. When we analyzed hematological parameters using Wilcoxon rank sum test to evaluate median (IQR) distribution based on malarial parasites and/or schistosomiasis infection status, there were significant differences in platelet counts (p = 0.0002), percent neutrophils, monocytes, eosinophils, and basophils (p < 0.0001 each). Amongst clinically relevant hematological abnormalities, eosinophilia was the most prevalent at 20.6% (116/562), whereas thrombocytopenia was the least prevalent at 4.3% (24/562). In univariate model, Chi-Square test performed for independence between participant distribution in different malaria parasitemia/schistosomiasis infection categories within each clinical hematological condition revealed significant differences for thrombocytopenia and eosinophilia (p = 0.006 and p < 0.0001, respectively), which was confirmed in multivariable models. Analysis of the pairwise mean differences of liver enzyme (ALT) and kidney function (Creatinine Clearance) indicated the presence of significant differences in ALT across the infection groups (parasite + /CCA + vs all other groups p < .003), but no differences in mean Creatinine Clearance across the infection groups. CONCLUSIONS: Our study demonstrates the high burden of asymptomatic malaria parasitemia and schistosomiasis infection in this rural population in Western Kenya. Asymptomatic infection with malaria or schistosomiasis was associated with laboratory abnormalities including neutropenia, leukopenia and thrombocytopenia. These abnormalities could be erroneously attributed to other diseases processes during evaluation of diseases processes. Therefore, evaluating for co-infections is key when assessing individuals with laboratory abnormalities. Additionally, asymptomatic infection needs to be considered in control and elimination programs given high prevalence documented here.


Assuntos
Coinfecção , Malária Falciparum , Malária , Esquistossomose , Adulto , Infecções Assintomáticas/epidemiologia , Coinfecção/epidemiologia , Estudos Transversais , Humanos , Quênia/epidemiologia , Malária/complicações , Malária/epidemiologia , Malária Falciparum/complicações , Malária Falciparum/epidemiologia , Plasmodium falciparum , Prevalência , Estudos Prospectivos , População Rural , Esquistossomose/complicações , Esquistossomose/epidemiologia
6.
PLoS One ; 16(3): e0249259, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33784358

RESUMO

BACKGROUND: Clinical laboratory reference intervals (RIs) are essential for diagnosing and managing patients in routine clinical care as well as establishing eligibility criteria and defining adverse events in clinical trials, but may vary by age, gender, genetics, nutrition and geographic location. It is, therefore, critical to establish region-specific reference values in order to inform clinical decision-making. METHODS: We analyzed data from a prospective observational HIV incidence cohort study in Kombewa, Kenya. Study participants were healthy males and females, aged 18-35 years, without HIV. Median and 95% reference values (2.5th percentile to 97.5th percentile) were calculated for laboratory parameters including hematology, chemistry studies, and CD4 T cell count. Standard Deviation Ratios (SDR) and Bias Ratios (BR) are presented as measures of effect magnitude. Findings were compared with those from the United States and other Kenyan studies. RESULTS: A total of 299 participants were analyzed with a median age of 24 years (interquartile range: 21-28). Ratio of males to females was 0.9:1. Hemoglobin range (2.5th-97.5th percentiles) was 12.0-17.9 g/dL and 9.5-15.3 g/dL in men and women respectively. In the cohort, MCV range was 59-95fL, WBC 3.7-9.2×103/µL, and platelet 154-401×103/µL. Chemistry values were higher in males; the creatinine RI was 59-103 µmol/L in males vs. 46-76 µmol/L in females (BRUL>.3); and the alanine transferase range was 8.8-45.3 U/L in males vs. 7.5-36.8 U/L in females (SDR>.3). The overall CD4 T cell count RI was 491-1381 cells/µL. Some parameters including hemoglobin, neutrophil, creatinine and ALT varied with that from prior studies in Kenya and the US. CONCLUSION: This study not only provides clinical reference intervals for a population in Kisumu County but also highlights the variations in comparable settings, accentuating the requirement for region-specific reference values to improve patient care, scientific validity, and quality of clinical trials in Africa.


Assuntos
Contagem de Linfócito CD4/normas , Hematologia/normas , Laboratórios , Adolescente , Adulto , Estudos de Coortes , Feminino , Humanos , Quênia , Masculino , Pessoa de Meia-Idade , Valores de Referência , Adulto Jovem
7.
IDCases ; 23: e01035, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33489756

RESUMO

BACKGROUND: Rapid diagnostic tests (RDT) are routinely used in screening for HIV infection. More complex diagnostic algorithms incorporating fourth-generation screening and confirmatory HIV-1/HIV-2 differentiation immunoassays (IA) may be used to confirm HIV infection. Co-infections and autoimmune diseases may lead to falsely reactive HIV diagnostic test results. CASE PRESENTATION: A Kenyan man with asymptomatic schistosomiasis and low risk factors for HIV infection demonstrated an inconsistent and discordant pattern of reactivity on HIV RDT, repeated reactivity on fourth-generation IA and positive at a single time-point for HIV-1 on the Geenius HIV1/HIV2 confirmatory assay during the course of a prospective cohort study with HIV repeat testing. The individual initiated antiretroviral therapy following HIV diagnosis. However, his bi-annual behavioral questionnaire suggested low-risk factors for infection. Supplementary confirmatory serologic and nucleic acid tests were performed and gave discordant results. The participant was determined to be HIV uninfected using cell-associated HIV-1 DNA/RNA testing and antiretroviral therapy was discontinued. DISCUSSION AND CONCLUSIONS: Sole reliance on diagnostic test results may result in misdiagnosis of HIV infection, social harm and potential antiretroviral induced drug toxicity. Interpretation of HIV test results should incorporate multiple parameters.

8.
PLoS One ; 15(4): e0232018, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32352972

RESUMO

INTRODUCTION: In many African countries, laboratory reference values are not established for the local healthy adult population. In Mozambique, reference values are known for young adults (18-24yo) but not yet established for a wider age range. Our study aimed to establish hematological, biochemical and immunological reference values for vaccine trials in Mozambican healthy adults with high-risk for HIV acquisition. METHODS: A longitudinal cohort and site development study in Mozambique between November 2013 and 2014 enrolled 505 participants between 18 to 35 years old. Samples from these healthy participants, were analyzed to determine reference values. All volunteers included in the analysis were clinically healthy and human immunodeficiency virus (HIV), hepatitis B and C virus, and syphilis negative. Median and reference ranges were calculated for the hematological, biochemical and immunological parameters. Ranges were compared with other African countries, the USA and the US National Institute of Health (NIH) Division of AIDS (DAIDS) toxicity tables. RESULTS: A total of 505 participant samples were analyzed. Of these, 419 participants were HIV, hepatitis B and C virus and syphilis negative including 203 (48.5%) females and 216 (51.5%) males, with a mean age of 21 years. In the hematological parameters, we found significant differences between sex for erythrocytes, hemoglobin, hematocrit, MCV, MCH and MCHC as well as white blood cells, neutrophils and platelets: males had higher values than females. There were also significant differences in CD4+T cell values, 803 cells/µL in men versus 926 cells/µL in women. In biochemical parameters, men presented higher values than women for the metabolic, enzymatic and renal parameters: total and direct bilirubin, ALT and creatinine. CONCLUSION: This study has established reference values for healthy adults with high-risk for HIV acquisition in Mozambique. These data are helpful in the context of future clinical research and patient care and treatment for the general adult population in the Mozambique and underline the importance of region-specific clinical reference ranges.


Assuntos
Células Sanguíneas/química , Infecções por HIV/prevenção & controle , Testes Hematológicos/normas , Adulto , Plaquetas/química , Estudos de Coortes , Feminino , Infecções por HIV/sangue , Hematócrito/normas , Hemoglobinas/análise , Humanos , Contagem de Leucócitos/normas , Leucócitos/química , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Moçambique/epidemiologia , Valores de Referência , Fatores de Risco
9.
Transfusion ; 53(3): 505-17, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22823283

RESUMO

BACKGROUND: Emergency whole blood transfusion is a lifesaving procedure employed on modern battlefields. Rapid device tests (RDTs) are frequently used to mitigate transfusion-transmitted infection risks. STUDY DESIGN AND METHODS: A limited evaluation of the RDT formerly used on battlefields was performed using 50 donor plasma samples and commercially available panels. Five hepatitis C virus (HCV) RDTs with sufficient stated sensitivity and thermostability were assessed using 335 HCV-positive and 339 HCV-negative donor plasma samples, 54 seroconversion panel plasma samples, and 84 HCV-positive and 84 HCV-negative spiked whole blood under normal, hot, and cold storage conditions and normal and hot test conditions, plus an ease-of-use survey. RESULTS: BioRapid HCV test sensitivity on donor plasma was 84% (95% confidence interval [CI], 70.9%-92.8%). Using all positive plasma samples, OraQuick HCV sensitivity exceeded all comparators (99.4%, 95% CI, 98.0%-99.9%, p<0.05). Specificity was consistently high, led by OraQuick HCV at 99.7% (95% CI, 98.6%-100%), statistically superior only to Axiom HCV (p<0.05). Using seroconversion panels, only OraQuick HCV showed equivalent or earlier HCV detection compared to the gold standard. Using spiked whole blood, specificity was consistently high, and sensitivity ranged significantly from 34.5% (95% CI, 25.0%-45.1%) for CORE HCV to 98.8% (95% CI, 94.3%-99.9%) for OraQuick HCV. All comparator RDTs were significantly less sensitive than OraQuick HCV at one or more stress condition. CONCLUSION: This HCV RDT comparison identified significant sensitivity differences, particularly using whole blood under extreme storage and testing conditions. These data support OraQuick HCV superiority and illustrate the value of RDT evaluation under simulated field conditions.


Assuntos
Doadores de Sangue , Seleção do Doador/métodos , Serviços Médicos de Emergência , Anticorpos Anti-Hepatite C/sangue , Kit de Reagentes para Diagnóstico , Algoritmos , Doadores de Sangue/estatística & dados numéricos , Preservação de Sangue/métodos , Segurança do Sangue , Técnicas de Laboratório Clínico/instrumentação , Técnicas de Laboratório Clínico/métodos , Eficiência , Serviços Médicos de Emergência/métodos , Serviços Médicos de Emergência/normas , Hepatite C/sangue , Hepatite C/diagnóstico , Anticorpos Anti-Hepatite C/análise , Humanos , Kit de Reagentes para Diagnóstico/normas , Sensibilidade e Especificidade , Fatores de Tempo
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