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1.
J Med Virol ; 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33554363

RESUMO

The implementation of rapid diagnostic tests (RDTs) may enhance the efficiency of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing, as RDTs are widely accessible and easy to use. The aim of this study was to evaluate the performance of a diagnosis strategy based on a combination of antigen and immunoglobulin M (IgM) or immunoglobulin G (IgG) serological RDTs. Plasma and nasopharyngeal samples were collected between 14 March and 11 April 2020 at hospital admission from 45 patients with reverse transcription polymerase chain reaction (RT-PCR) confirmed COVID-19 and 20 negative controls. SARS-CoV-2 antigen (Ag) was assessed in nasopharyngeal swabs using the Coris Respi-Strip. For IgM/IgG detection, SureScreen Diagnostics and Szybio Biotech RDTs were used in addition to laboratory assays (Abbott Alinity i SARS-CoV-2 IgG and Theradiag COVID-19 IgM enzyme-linked immunosorbent assay). Using the Ag RDT, 13 out of 45 (29.0%) specimens tested positive, the sensitivity was 87.0% for cycle threshold (Ct ) values ≤25% and 0% for Ct values greater than 25. IgG detection was associated with high Ct values and the amount of time after the onset of symptoms. The profile of isolated IgM on RDTs was more frequently observed during the first and second week after the onset of symptoms. The combination of Ag and IgM/IgG RDTs enabled the detection of up to 84.0% of COVID-19 confirmed cases at hospital admission. Antigen and antibody-based RDTs showed suboptimal performances when used alone. However when used in combination, they are able to identify most COVID-19 patients admitted in an emergency department.

2.
Pathogens ; 9(12)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33266071

RESUMO

West Nile virus (WNV) and Usutu virus (USUV) are zoonotic arboviruses. These flaviviruses are mainly maintained in the environment through an enzootic cycle involving mosquitoes and birds. Horses and humans are incidental, dead-end hosts, but can develop severe neurological disorders. Nevertheless, there is little data regarding the involvement of other mammals in the epidemiology of these arboviruses. In this study, we performed a serosurvey to assess exposure to these viruses in captive birds and mammals in a zoo situated in the south of France, an area described for the circulation of these two viruses. A total of 411 samples comprising of 70 species were collected over 16 years from 2003 to 2019. The samples were first tested by a competitive enzyme-linked immunosorbent assay. The positive sera were then tested using virus-specific microneutralization tests against USUV and WNV. USUV seroprevalence in birds was 10 times higher than that of WNV (14.59% versus 1.46%, respectively). Among birds, greater rhea (Rhea Americana) and common peafowl (Pavo cristatus) exhibited the highest USUV seroprevalence. Infections occurred mainly between 2016-2018 corresponding to a period of high circulation of these viruses in Europe. In mammalian species, antibodies against WNV were detected in one dama gazelle (Nanger dama) whereas serological evidence of USUV infection was observed in several Canidae, especially in African wild dogs (Lycaon pictus). Our study helps to better understand the exposure of captive species to WNV and USUV and to identify potential host species to include in surveillance programs in zoos.

3.
J Infect Dis ; 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33206973

RESUMO

We assessed the expression of CD169, a type I interferon-inducible receptor, on monocytes (mCD169) in 53 adult patients admitted to the hospital during the COVID-19 outbreak for a suspicion of SARS-CoV-2 infection. mCD169 was strongly overexpressed in 30 out of 32 (93.7%) confirmed COVID-19 cases, compared to three out of 21 (14.3%) patients in whom the diagnosis of COVID-19 was finally ruled out. mCD169 was associated with the plasma interferon alpha level and thrombocytopenia. mCD169 testing may be helpful for the rapid triage of suspected COVID-19 patients during an outbreak.

4.
mBio ; 11(4)2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32753493

RESUMO

The blood-brain barrier (BBB) largely prevents toxins and pathogens from accessing the brain. Some viruses have the ability to cross this barrier and replicate in the central nervous system (CNS). Zika virus (ZIKV) was responsible in 2015 to 2016 for a major epidemic in South America and was associated in some cases with neurological impairments. Here, we characterized some of the mechanisms behind its neuroinvasion using an innovative in vitro human BBB model. ZIKV efficiently replicated, was released on the BBB parenchyma side, and triggered subtle modulation of BBB integrity as well as an upregulation of inflammatory and cell adhesion molecules (CAMs), which in turn favored leukocyte recruitment. Finally, we showed that ZIKV-infected mouse models displayed similar CAM upregulation and that soluble CAMs were increased in plasma samples from ZIKV-infected patients. Our observations suggest a complex interplay between ZIKV and the BBB, which may trigger local inflammation, leukocyte recruitment, and possible cerebral vasculature impairment.IMPORTANCE Zika virus (ZIKV) can be associated with neurological impairment in children and adults. To reach the central nervous system, viruses have to cross the blood-brain barrier (BBB), a multicellular system allowing a tight separation between the bloodstream and the brain. Here, we show that ZIKV infects cells of the BBB and triggers a subtle change in its permeability. Moreover, ZIKV infection leads to the production of inflammatory molecules known to modulate BBB integrity and participate in immune cell attraction. The virus also led to the upregulation of cellular adhesion molecules (CAMs), which in turn favored immune cell binding to the BBB and potentially increased infiltration into the brain. These results were also observed in a mouse model of ZIKV infection. Furthermore, plasma samples from ZIKV-infected patients displayed an increase in CAMs, suggesting that this mechanism could be involved in neuroinflammation triggered by ZIKV.

5.
Clin Infect Dis ; 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32516409

RESUMO

BACKGROUND: Human encephalitis represents a medical challenge from a diagnostic and therapeutic point of view. We investigated the cause of 2 fatal cases of encephalitis of unknown origin in immunocompromised patients. METHODS: Untargeted metatranscriptomics was applied on the brain tissue of 2 patients to search for pathogens (viruses, bacteria, fungi, or protozoans) without a prior hypothesis. RESULTS: Umbre arbovirus, an orthobunyavirus never previously identified in humans, was found in 2 patients. In situ hybridization and reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) showed that Umbre virus infected neurons and replicated at high titers. The virus was not detected in cerebrospinal fluid by RT-qPCR. Viral sequences related to Koongol virus, another orthobunyavirus close to Umbre virus, were found in Culex pipiens mosquitoes captured in the south of France where the patients had spent some time before the onset of symptoms, demonstrating the presence of the same clade of arboviruses in Europe and their potential public health impact. A serological survey conducted in the same area did not identify individuals positive for Umbre virus. The absence of seropositivity in the population may not reflect the actual risk of disease transmission in immunocompromised individuals. CONCLUSIONS: Umbre arbovirus can cause encephalitis in immunocompromised humans and is present in Europe.

6.
PLoS Negl Trop Dis ; 14(4): e0008223, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32324736

RESUMO

Usutu virus (USUV), an African mosquito-borne flavivirus closely related to West Nile virus, was first isolated in South Africa in 1959. USUV emerged in Europe two decades ago, causing notably massive mortality in Eurasian blackbirds. USUV is attracting increasing attention due to its potential for emergence and its rapid spread in Europe in recent years. Although mainly asymptomatic or responsible for mild clinical signs, USUV was recently described as being associated with neurological disorders in humans such as encephalitis and meningoencephalitis, highlighting the potential health threat posed by the virus. Despite this, USUV pathogenesis remains largely unexplored. The aim of this study was to evaluate USUV neuropathogenicity using in vivo and in vitro approaches. Our results indicate that USUV efficiently replicates in the murine central nervous system. Replication in the spinal cord and brain is associated with recruitment of inflammatory cells and the release of inflammatory molecules as well as induction of antiviral-responses without major modulation of blood-brain barrier integrity. Endothelial cells integrity is also maintained in a human model of the blood-brain barrier despite USUV replication and release of pro-inflammatory cytokines. Furthermore, USUV-inoculated mice developed major ocular defects associated with inflammation. Moreover, USUV efficiently replicates in human retinal pigment epithelium. Our results will help to better characterize the physiopathology related to USUV infection in order to anticipate the potential threat of USUV emergence.


Assuntos
Flavivirus/patogenicidade , Modelos Biológicos , Sistema Nervoso/virologia , Animais , Encéfalo/virologia , Modelos Animais de Doenças , Células Endoteliais/virologia , Células Epiteliais/virologia , Flavivirus/crescimento & desenvolvimento , Humanos , Camundongos , Epitélio Pigmentado Ocular/virologia , Medula Espinal/virologia
7.
Front Microbiol ; 11: 373, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210946

RESUMO

Blood collected and dried on a paper card - dried blood spot (DBS) - knows a growing interest as a sampling method that can be performed outside care facilities by capillary puncture, and transported in a simple and safe manner by mail. The benefits of this method for blood collection and transport has recently led the World Health Organization to recommend DBS for HIV and hepatitis B and C diagnosis. The clinical utility of DBS sampling to improve diagnostics and care of HIV and hepatitis B and C infection in hard to reach populations, key populations and people living in low-income settings was highlighted. Literature about usefulness of DBS specimens in the therapeutic cascade of care - screening, confirmation, quantification of nucleic acids, and resistance genotyping -, was reviewed. DBS samples are suitable for testing antibodies, antigens, or nucleic acids using most laboratory methods. Good sensibility and specificity have been reported for infant HIV diagnosis and diagnosis of hepatitis B and C. The performance of HIV RNA testing on DBS to identified virological failure on antiretroviral therapy is also high but not optimal because of the dilution of dried blood in the elution buffer, reducing the analytical sensitivity, and because of the contamination by intracellular HIV DNA. Standardized protocols are needed for inter-laboratory comparisons, and manufacturers should pursue regulatory approval for in vitro diagnostics using DBS specimens. Despite these limitations, DBS sampling is a clinically relevant tool to improve access to infectious disease diagnosis worldwide.

8.
Clin Infect Dis ; 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32067040

RESUMO

BACKGROUND: Immune control of Epstein-Barr virus (EBV) infection is impaired in HIV-infected individuals. We explored maternal factors associated with EBV acquisition in HIV-exposed uninfected (HEU) infants and the relationship between EBV infection and serious adverse events (SAE) during the first year of life. METHODS: Two hundred and one HEU infants from Uganda enrolled in the ANRS12174 trial were tested for anti-viral capsid antigen (VCA) antibodies at week 50 of life. The date of infection was estimated by testing of EBV DNA at weeks 1, 6, 14, 26, 38 and 50 postpartum on dried blood spot (DBS). RESULTS: Eighty-seven (43%) infants were tested positive for anti-VCA IgG at week 50. Among the 59 infants positive for EBV DNA, 25% were infected within the first 26 weeks. Almost half of them (12%) were infected before week 14. Shedding of EBV in breast milk was associated with EBV DNA in maternal plasma (P=.009), HIV RNA detection (P=.039), lower CD4 count (P=.001) and was correlated with plasma EBV DNA levels (P=.002). EBV infant infection at week 50 was associated with shedding of EBV in breast milk (P=.009) and young maternal age (P=.029). Occurrence of a clinical SAE, including malaria and pneumonia, was associated with higher levels of EBV DNA in infants (P=.010). CONCLUSIONS: By assessing EBV infection in HEU infants we observed that infection during the first year of life is determined by HIV and EBV maternal factors and that EBV DNA levels was higher among infants with clinical SAE.

9.
J Viral Hepat ; 27(5): 540-543, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31895489

RESUMO

Diagnostic of acute hepatitis A virus (HAV) infection is based on the detection of anti-HAV IgM without testing for the pathogen itself. We evaluated the usefulness of HAV RNA testing for confirmation of acute hepatitis A and to provide indications about the level of HAV replication in HIV-positive and HIV-negative subjects during an unprecedented outbreak of HAV observed in France in 2017. HAV RNA was detected in 38 out of 41 (92.6%) subjects with a clinical diagnosis of acute hepatitis A, whereas nine cases tested positive for anti-HAV IgM in whom the diagnosis of acute hepatitis A was not retained were found negative for HAV RNA. All subjects in the control group were also tested negative for HAV RNA. HAV viremia was correlated to ALT peak (r = .64; P < .0001). HIV-infected patients have similar HAV RNA levels but were less likely to have prolonged international normalized ratio of prothrombin time when compared to the HIV-uninfected group (P = .016), suggesting a less severe course of acute hepatitis. HAV RNA was detected in the serum of most of the patients with acute hepatitis A, indicating that the direct detection of HAV can be used to confirm hepatitis A in patients tested positive for anti-HAV IgM antibodies. Nucleic acid tests should serve more broadly during the diagnosis workup of acute hepatitis A to improve the predictive values of HAV in vitro diagnostic tests and to confirm acute hepatitis A in patients tested positive with IgM with moderate or low S/CO values.

10.
Front Immunol ; 10: 1153, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191532

RESUMO

Primary Sjögren's syndrome (pSS) is characterized by B cell hyperactivation, production of autoantibodies and increased risk of B cell lymphomas. Serological profile of Epstein-Barr virus (EBV) reactivation and increase EBV DNA levels in exocrine glands are observed in pSS, but whether these abnormalities are accompanied with disturbed systemic EBV control or have any association with pSS activity remains to be investigated. In this observational study, we initially explored anti-EBV antibodies and cell-free DNA in 395 samples from a cross-sectional plasma collection of pSS patients included in ASSESS French national cohort. Results were assessed in relation with disease activity. Further, to assess cell-associated EBV DNA we organized a case-control study including 20 blood samples from pSS patients followed in University Hospital Center of Montpellier. Results were compared with matched controls. Robust response against EBV early antigen (EA) was observed in pSS patients with anti-SSA/B (Sjögren's syndrome A and B) and anti-SSA autoantibodies compared to anti-SSA/B negatives (P < 0.01 and P = 0.01, respectively). Increased beta-2 microglobulin, kappa and lambda light chains, and immunoglobulin G levels were more frequently observed in anti-EA seropositive pSS subjects compared to anti-EA negative subjects (P < 0.001; P = 0.001; P = 0.003, respectively). Beta-2 microglobulin was independently associated with anti-EA positivity in multivariate analysis (P < 0.001). Plasma cell-free EBV DNA and EBV cellular reservoir was not different between pSS patients and controls. We conclude that serological evidence of EBV reactivation was more frequently observed and more strongly associated with anti-SSA/B status and B cell activation markers in pSS. However, serological profile of EBV reactivation was not accompanied by molecular evidence of systemic EBV reactivation. Our data indicated that EBV infection remains efficiently controlled in the blood of pSS patients.


Assuntos
Anticorpos Antinucleares/sangue , Anticorpos Antivirais/sangue , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/fisiologia , Síndrome de Sjogren/imunologia , Ativação Viral , Adulto , Idoso , Autoantígenos/imunologia , Linfócitos B/imunologia , Biomarcadores , Estudos de Casos e Controles , DNA Viral/análise , DNA Viral/sangue , Infecções por Vírus Epstein-Barr/virologia , Glândulas Exócrinas/virologia , Feminino , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/imunologia , Humanos , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Ribonucleoproteínas/imunologia , Síndrome de Sjogren/sangue , Síndrome de Sjogren/complicações , Síndrome de Sjogren/virologia , Microglobulina beta-2/análise
11.
EBioMedicine ; 39: 315-331, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30579862

RESUMO

BACKGROUND: Zika virus (ZIKV) has recently re-emerged as a pathogenic agent with epidemic capacities as was well illustrated in South America. Because of the extent of this health crisis, a number of more serious symptoms have become associated with ZIKV infection than what was initially described. In particular, neuronal and ocular disorders have been characterized, both in infants and in adults. Notably, the macula and the retina can be strongly affected by ZIKV, possibly by a direct effect of the virus. This is supported by the detection of replicative and infectious virus in lachrimal fluid in human patients and mouse models. METHODS: Here, we used an innovative, state-of-the-art iPSC-derived human retinal pigment epithelium (RPE) model to study ZIKV retinal impairment. FINDINGS: We showed that the human RPE is highly susceptible to ZIKV infection and that a ZIKV African strain was more virulent and led to a more potent epithelium disruption and stronger anti-viral response than an Asian strain, suggesting lineage differences. Moreover, ZIKV infection led to impaired membrane dynamics involved in endocytosis, organelle biogenesis and potentially secretion, key mechanisms of RPE homeostasis and function. INTERPRETATION: Taken together, our results suggest that ZIKV has a highly efficient ocular tropism, which creates a strong inflammatory environment that could have acute or chronic adverse effects. FUND: This work was funded by Retina France, REACTing and La Région Languedoc-Roussillon.


Assuntos
Interferons/metabolismo , Epitélio Pigmentado da Retina/virologia , Infecção por Zika virus/imunologia , Zika virus/patogenicidade , Células Cultivadas , Homeostase , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/imunologia , Células-Tronco Pluripotentes Induzidas/virologia , Interferons/genética , Modelos Biológicos , Fagocitose , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/imunologia , Tropismo Viral , Replicação Viral , Zika virus/classificação , Zika virus/fisiologia , Infecção por Zika virus/genética , Infecção por Zika virus/virologia
12.
J Clin Lab Anal ; 33(3): e22719, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30474140

RESUMO

BACKGROUND: Little is known about the involvement of herpes simplex virus (HSV) or Mycobacterium tuberculosis (MTB) as potentially curable causes of central nervous system (CNS) infections in sub-Saharan Africa. OBJECTIVE: In this study, we developed a PCR assay dedicated to simultaneous testing of HSV1/HSV2 and MTB in Burkina Faso, a country where HSV is neglected as a cause of CNS infection and where TB prevalence is high. METHODS: A consensus HSV1/HSV2 set of primers and probe were designed and combined to primers and probe targeting the IS6110 repetitive insertion sequence of MTB. Analytical performances of the assay were evaluated on reference materials. Cerebrospinal fluid (CSF) collected from subjects with aseptic meningitis was tested for HSV1/HSV2 and MTB DNA. RESULTS: The UL29 gene was chosen as a highly conserved region targeted by the HSV1/HSV2 nucleic acid test. The lower limits of detection were estimated to be 2.45 copies/µL for HSV1, 1.72 copies/µL for HSV2, and 2.54 IS6110 copies per µL for MTB. The PCR was used in 202 CSF collected from subjects suspected of aseptic meningitis. Five samples (2.46%) tested positive, including two children positive for HSV1 (0.99%) and three adults tested positive for MTB (1.47%). CONCLUSION: Using an in-house real-time PCR assay, we showed that both HSV and MTB are etiologic pathogens contributing to aseptic meningitis in Burkina Faso. This molecular test may have clinical utility for early diagnosis for those treatable CNS infections.


Assuntos
DNA Bacteriano/líquido cefalorraquidiano , DNA Viral/líquido cefalorraquidiano , Herpes Simples/diagnóstico , Meningite Asséptica/diagnóstico , Tipagem Molecular/métodos , Tuberculose Meníngea/diagnóstico , Adulto , Burkina Faso , Criança , Herpesvirus Humano 1/genética , Herpesvirus Humano 2/genética , Humanos , Limite de Detecção , Meningite Asséptica/microbiologia , Meningite Asséptica/virologia , Mycobacterium tuberculosis/genética
13.
BMC Infect Dis ; 18(1): 622, 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30514229

RESUMO

BACKGROUND: Nucleic acid tests performed on blood samples collected on Dried Blood Spot (DBS) and detection of HCV core antigen (HCVcAg) are two approaches that may facilitate access to HCV diagnosis in low and middle incomes countries. In this study we evaluate HCV RNA and HCV antigen testing on DBS in HIV/HCV co-infected peoples who inject drugs in Vietnam. METHOD: One hundred and four HIV/HCV seropositive patients managed in outpatient care at the Haiphong Viet Tiep hospital were included in this study from February to March, 2014 (ANRS 12262 study). RESULTS: Eighty-six subjects were tested positive for HCV RNA in serum, median (IQR): 6.9 log10 IU/ml (5.6-7.4 log10 IU/ml). Genotypes consisted of 57 G1 (69%), 3 G3 (4%), and 22 G6 (27%). HCV RNA was detected on DBS specimens in 79 out 86 subjects with chronic hepatitis C (sensitivity 92.5%; 95% CI: 85.1-96.9%). HCV RNA level on DBS and serum was moderately correlated (r = 0.24; p = 0.05) suggesting a degradation of HCV RNA due to transportation and storage conditions. HCVcAg was detected in 75/86 dB specimens (sensitivity: 87.2%; 95% CI: 78.3-93.4%), with a strong positive relationship between DBS HCVcAg and serum HCV RNA levels (r = 0.80; P < 0.0001). CONCLUSIONS: Quantification of HCVcAg on DBS appears to benefit from substantial stability under prolonged storage conditions but with a lower analytical sensitivity compared to DBS HCV RNA testing. Detection of HCV RNA on DBS is an interesting approach for confirming viral replication in HCV seropositive persons but the impact of pre-analytical conditions on the integrity of HCV RNA needs to be controlled.


Assuntos
Teste em Amostras de Sangue Seco/métodos , Infecções por HIV/virologia , Hepatite C/virologia , RNA Viral/análise , Abuso de Substâncias por Via Intravenosa/virologia , Proteínas do Core Viral/análise , Viremia/diagnóstico , Adulto , Coinfecção , Estudos Transversais , Testes Diagnósticos de Rotina , Usuários de Drogas , Feminino , Genótipo , HIV/genética , Infecções por HIV/sangue , Infecções por HIV/complicações , Hepacivirus/genética , Hepatite C/sangue , Hepatite C/complicações , Hepatite C/diagnóstico , Humanos , Testes Imunológicos , Injeções , Masculino , RNA Viral/sangue , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Abuso de Substâncias por Via Intravenosa/sangue , Abuso de Substâncias por Via Intravenosa/complicações , Vietnã , Proteínas do Core Viral/sangue , Proteínas do Core Viral/genética , Viremia/sangue , Viremia/genética
14.
Bull World Health Organ ; 96(11): 750-759, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30455530

RESUMO

Objective: To estimate population-wide hepatitis B and C seroprevalence using dried blood spot samples acquired for human immunodeficiency virus (HIV) surveillance as part of the 2010-2011 Demographic and Health Survey in Burkina Faso. Methods: We used the database acquired during the multistage, clustered, population-based survey, in which 15 377 participants completed questionnaires and provided dried blood spot samples for HIV testing. We extracted sociodemographic and geographic data including age, sex, ethnicity, education, wealth, marital status and region for each participant. We performed hepatitis B and C assays on 14 886 HIV-negative samples between March to October 2015, and calculated weighted percentages of hepatitis seroprevalence for each variable. Findings: We estimated seroprevalence as 9.1% (95% confidence interval, CI: 8.5-9.7) for the hepatitis B surface antigen and 3.6% (95% CI: 3.3-3.8) for hepatitis C virus antibodies, classifying Burkina Faso as highly endemic for hepatitis B and low-intermediate for hepatitis C. The seroprevalence of hepatitis was higher in men than in women, and varied significantly for both with age, education, ethnicity and region. Extremely high HCV-Ab seroprevalence (13.2%; 95% CI: 10.6-15.7) was identified in the Sud-Ouest region, in particular within the youngest age group (15-20 years), indicating an ongoing epidemic. Conclusion: Our population-representative hepatitis seroprevalence estimates in Burkina Faso advocate for the inclusion of hepatitis serological tests and risk factor questionnaire items in future surveys, the results of which are crucial for the development of appropriate health policies and infection control programmes.


Assuntos
Hepatite B/epidemiologia , Hepatite C/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Burkina Faso/epidemiologia , Estudos Transversais , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Características de Residência , Fatores de Risco , Estudos Soroepidemiológicos , Distribuição por Sexo , Fatores Socioeconômicos , Adulto Jovem
15.
J Transl Med ; 16(1): 296, 2018 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-30359283

RESUMO

BACKGROUND: Subclinical mastitis (SCM) is relatively common in lactating women and may be associated with HIV shedding in breast milk. The potential association between HIV infection and breast milk immunologic factors and immune response to SCM needs to be addressed. METHODS: In this cross-sectional study, SCM (Na/K ratio > 1) was tested in 165 mature breast milk samples collected from 40 HIV-infected women who didn't transmit HIV to their child by breastfeeding and 43 HIV-uninfected women enrolled in an interventional cohort in South-Africa (Vertical Transmission Study). The level of 33 immune markers related to Th1/Th2 related response, inflammation and bacterial exposure were compared in ART-naive HIV-infected versus HIV-uninfected women. The associations between HIV infection and SCM on the concentration of immune factors were tested separately by Wilcoxon rank-sum test and corrected for false discovery rate. To control for potential confounder effects and take into account the clustering of breast milk samples from a single woman, multivariate mixed linear models adjusted on child age at the time of sampling were performed for each immune factor. RESULTS: Subclinical mastitis was detected in 15 (37.5%) HIV-infected women and 10 (23.3%) HIV-uninfected women. In the absence of SCM, the breast milk levels of IP-10 and MIG were higher and IL1-RA lower in HIV-infected women than in HIV-uninfected women (respectively p < 0.001, p = 0.001, p = 0.045). In HIV-uninfected women, SCM was characterized by a robust immune response with higher concentrations of a broad panel of Th1 and inflammatory related immune markers than in samples without SCM. By contrast, in HIV-infected women a limited number of immune markers were increased and lower increases were observed in samples with SCM than without SCM. CONCLUSION: HIV infection in ART-naïve women was associated with elevated breast milk levels of IP-10 and MIG, which areTh1-related cytokines induced by IFN-γ. During SCM, a lower and narrower immune response was observed in HIV-infected than HIV-uninfected women, suggesting that HIV infection affects the capacity of the mammary gland to respond to SCM.


Assuntos
Infecções por HIV/complicações , Mastite/complicações , Mastite/imunologia , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Leite Humano/imunologia , Estatísticas não Paramétricas , Adulto Jovem
17.
PLoS One ; 12(8): e0183856, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28850597

RESUMO

BACKGROUND: Viral load monitoring and early Epstein-Barr virus (EBV) DNA detection are essential in routine laboratory testing, especially in preemptive management of Post-transplant Lymphoproliferative Disorder. Targeting the repetitive BamHI-W sequence was shown to increase the sensitivity of EBV DNA quantification, but the variability of BamHI-W reiterations was suggested to be a source of quantification bias. We aimed to assess the extent of variability associated with BamHI-W PCR and its impact on the sensitivity of EBV DNA quantification using the 1st WHO international standard, EBV strains and clinical samples. METHODS: Repetitive BamHI-W- and LMP2 single- sequences were amplified by in-house qPCRs and BXLF-1 sequence by a commercial assay (EBV R-gene™, BioMerieux). Linearity and limits of detection of in-house methods were assessed. The impact of repeated versus single target sequences on EBV DNA quantification precision was tested on B95.8 and Raji cell lines, possessing 11 and 7 copies of the BamHI-W sequence, respectively, and on clinical samples. RESULTS: BamHI-W qPCR demonstrated a lower limit of detection compared to LMP2 qPCR (2.33 log10 versus 3.08 log10 IU/mL; P = 0.0002). BamHI-W qPCR underestimated the EBV DNA load on Raji strain which contained fewer BamHI-W copies than the WHO standard derived from the B95.8 EBV strain (mean bias: - 0.21 log10; 95% CI, -0.54 to 0.12). Comparison of BamHI-W qPCR versus LMP2 and BXLF-1 qPCR showed an acceptable variability between EBV DNA levels in clinical samples with the mean bias being within 0.5 log10 IU/mL EBV DNA, whereas a better quantitative concordance was observed between LMP2 and BXLF-1 assays. CONCLUSIONS: Targeting BamHI-W resulted to a higher sensitivity compared to LMP2 but the variable reiterations of BamHI-W segment are associated with higher quantification variability. BamHI-W can be considered for clinical and therapeutic monitoring to detect an early EBV DNA and a dynamic change in viral load.


Assuntos
DNA Viral , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Herpesvirus Humano 4/genética , Humanos , Sequências Repetitivas de Ácido Nucleico , Sensibilidade e Especificidade , Carga Viral
18.
PLoS One ; 11(9): e0162137, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27603919

RESUMO

Interferon gamma (IFN-γ) release assays (IGRAs) detect Mycobacterium tuberculosis (Mtb) infection regardless of the active (ATB) or latent (LTBI) forms of tuberculosis (TB). In this study, Mtb-specific T cell response against region of deletion 1 (RD1) antigens were explored by a microbead multiplex assay performed in T-SPOT TB assay (T-SPOT) supernatants from 35 patients with ATB and 115 patients with LTBI. T-SPOT is positive when over 7 IFN-γ secreting cells (SC)/250 000 peripheral blood mononuclear cells (PBMC) are enumerated. However, over 100 IFN-γ SC /250 000 PBMC were more frequently observed in the ATB group compared to the LTBI group. By contrast, lower cytokine concentrations and lower cytokine productions relative to IFN-γ secretion were observed for IL 4, IL-12, TNF-α, GM-CSF, Eotaxin and IFN-α when compared to LTBI. Thus, high IFN-γ release and low cytokine secretions in relation with IFN-γ production appeared as signatures of ATB, corroborating that multicytokine Mtb-specific response against RD1 antigens reflects host capacity to contain TB reactivation. In this way, testing cytokine profile in IGRA supernatants would be helpful to improve ATB screening strategy including immunologic tests.


Assuntos
Testes de Liberação de Interferon-gama/métodos , Interferon gama/metabolismo , Tuberculose/imunologia , Adulto , Idoso , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Feminino , Humanos , Tuberculose Latente/diagnóstico , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Razão de Chances , Kit de Reagentes para Diagnóstico
19.
Medicine (Baltimore) ; 95(27): e4005, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27399077

RESUMO

Epstein-Barr virus (EBV) in breast milk and subclinical mastitis (SCM) are both associated with human immunodeficiency virus (HIV) shedding and possibly with postnatal HIV transmission. The objective of this nested case-control study was to investigate the interplay between SCM and EBV replication in breast milk of HIV-infected mothers.The relationships between EBV deoxyribonucleic acid (DNA) shedding, HIV-1 ribonucleic acid (RNA) level, and SCM were explored in breast milk samples of Zambian mothers participating in the ANRS 12174 trial. Mammary gland inflammation was defined as a breast milk sodium to potassium ratio (Na/K) greater than 0.6 and further subclassified as either "possible SCM" (Na/K ratio 0.6-1.0) or SCM (Na/K ratio ≥ 1.0). Breast milk interleukin 8 (IL-8) was measured as a surrogate marker of mammary gland inflammation.EBV DNA was detected in breast milk samples from 42 out of 83 (51%) participants and was associated with HIV-1 shedding in breast milk (P = 0.006). EBV DNA levels were higher in samples with SCM and "possible SCM" compared to non-SCM breast milk samples (P = 0.06; P = 0.007). An EBV DNA level of >200 copies/mL was independently associated with SCM and "possible SCM" (OR: 2.62; 95%: 1.13-6.10). In patients with SCM, higher EBV replication in the mammary gland was associated with a lower induction of IL-8 (P = 0.013). Resistance to DNase treatment suggests that EBV DNA in lactoserum is encapsidated.SCM and decreased IL-8 responses are associated with an increased EBV shedding in breast milk which may in turn facilitate HIV replication in the mammary gland.


Assuntos
Infecções por HIV/transmissão , HIV-1/fisiologia , Herpesvirus Humano 4/fisiologia , Transmissão Vertical de Doença Infecciosa , Mastite/virologia , Leite Humano/virologia , Eliminação de Partículas Virais , Adulto , Contagem de Linfócito CD4 , DNA Viral/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Recém-Nascido , RNA Viral/análise , Zâmbia
20.
J Clin Microbiol ; 54(6): 1641-1643, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27008874

RESUMO

The impact of HIV-1 DNA coamplification during HIV-1 RNA quantification on dried blood spots (DBS) was explored. False-positive HIV RNA detection (22/62, 35%) was associated with high HIV-1 DNA levels. Specificity of HIV-1 RNA assays on DBS should be evaluated following manufacturer protocols on samples with HIV-1 DNA levels of ≥1,000 copies/10(6) peripheral blood mononuclear cells.


Assuntos
DNA Viral/sangue , Erros de Diagnóstico , Infecções por HIV/virologia , HIV-1/isolamento & purificação , RNA Viral/sangue , Manejo de Espécimes/métodos , Carga Viral/métodos , Dessecação , Monitoramento de Medicamentos/métodos , Reações Falso-Positivas , Infecções por HIV/tratamento farmacológico , Humanos
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