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Every Ebola outbreak is most likely the result of independent zoonotic events. More than four decades after the first identification of the Ebola virus, its reservoir remains unknown. We have shown in this work that the prevalence of Ebola virus in wildlife was very low with antibodies against Ebola virus (Zaire and / or Sudan) detected in less than 1% of bats tested in the DRC, Guinea and Cameroon; and 0% in non-human primates from the DRC, Cote d'Ivoire and Cameroon, during inter-epidemic period. No antibodies were detected in samples collected during the epidemic period in the DRC, and the search for Ebola RNA in these studies was negative. Nevertheless, we have confirmed and characterized in humans, new variants of the Ebola virus which caused the recent outbreaks of 2018 in the DRC. Early and ongoing genomic sequencing has been used to guide public health interventions.Thus, despite the presence of antibodies to the Ebola virus, the role of bats as a reservoir species remains unclear, as the detection of viral RNA is still rare. Ebola virus antibodies are very rare in non-human primates, confirming that PNH are not reservoir species. Efforts to recover the reservoir of this virus must continue because it is the only way that will allow us to effectively prevent future outbreaks. ; Chaque épidémie de la maladie à virus Ebola résulte très probablement d'événements zoonotiques indépendants. Plus de quatre décennies après la première identification du virus Ebola, son réservoir demeure encore inconnu. Nous avons montré dans ce travail que la prévalence du virus Ebola dans la faune sauvage était très faible avec une présence d'anticorps anti-virus Ebola (Zaïre et/ou Sudan) chez moins de 1% des chauves-souris testées de la RDC, Guinée et Cameroun ; et de 0% chez les primates non humains de la RDC, Cote d'Ivoire et Cameroun, en période inter-épidémique. Aucun anticorps n'a été détecté dans les échantillons prélevés en période épidémique en RDC. La recherche de l'ARN du virus Ebola, au cours de ces études, était ...

Every Ebola outbreak is most likely the result of independent zoonotic events. More than four decades after the first identification of the Ebola virus, its reservoir remains unknown. We have shown in this work that the prevalence of Ebola virus in wildlife was very low with antibodies against Ebola virus (Zaire and / or Sudan) detected in less than 1% of bats tested in the DRC, Guinea and Cameroon; and 0% in non-human primates from the DRC, Cote d'Ivoire and Cameroon, during inter-epidemic period. No antibodies were detected in samples collected during the epidemic period in the DRC, and the search for Ebola RNA in these studies was negative. Nevertheless, we have confirmed and characterized in humans, new variants of the Ebola virus which caused the recent outbreaks of 2018 in the DRC. Early and ongoing genomic sequencing has been used to guide public health interventions.Thus, despite the presence of antibodies to the Ebola virus, the role of bats as a reservoir species remains unclear, as the detection of viral RNA is still rare. Ebola virus antibodies are very rare in non-human primates, confirming that PNH are not reservoir species. Efforts to recover the reservoir of this virus must continue because it is the only way that will allow us to effectively prevent future outbreaks. ; Chaque épidémie de la maladie à virus Ebola résulte très probablement d'événements zoonotiques indépendants. Plus de quatre décennies après la première identification du virus Ebola, son réservoir demeure encore inconnu. Nous avons montré dans ce travail que la prévalence du virus Ebola dans la faune sauvage était très faible avec une présence d'anticorps anti-virus Ebola (Zaïre et/ou Sudan) chez moins de 1% des chauves-souris testées de la RDC, Guinée et Cameroun ; et de 0% chez les primates non humains de la RDC, Cote d'Ivoire et Cameroun, en période inter-épidémique. Aucun anticorps n'a été détecté dans les échantillons prélevés en période épidémique en RDC. La recherche de l'ARN du virus Ebola, au cours de ces études, était ...

Every Ebola outbreak is most likely the result of independent zoonotic events. More than four decades after the first identification of the Ebola virus, its reservoir remains unknown. We have shown in this work that the prevalence of Ebola virus in wildlife was very low with antibodies against Ebola virus (Zaire and / or Sudan) detected in less than 1% of bats tested in the DRC, Guinea and Cameroon; and 0% in non-human primates from the DRC, Cote d'Ivoire and Cameroon, during inter-epidemic period. No antibodies were detected in samples collected during the epidemic period in the DRC, and the search for Ebola RNA in these studies was negative. Nevertheless, we have confirmed and characterized in humans, new variants of the Ebola virus which caused the recent outbreaks of 2018 in the DRC. Early and ongoing genomic sequencing has been used to guide public health interventions.Thus, despite the presence of antibodies to the Ebola virus, the role of bats as a reservoir species remains unclear, as the detection of viral RNA is still rare. Ebola virus antibodies are very rare in non-human primates, confirming that PNH are not reservoir species. Efforts to recover the reservoir of this virus must continue because it is the only way that will allow us to effectively prevent future outbreaks. ; Chaque épidémie de la maladie à virus Ebola résulte très probablement d'événements zoonotiques indépendants. Plus de quatre décennies après la première identification du virus Ebola, son réservoir demeure encore inconnu. Nous avons montré dans ce travail que la prévalence du virus Ebola dans la faune sauvage était très faible avec une présence d'anticorps anti-virus Ebola (Zaïre et/ou Sudan) chez moins de 1% des chauves-souris testées de la RDC, Guinée et Cameroun ; et de 0% chez les primates non humains de la RDC, Cote d'Ivoire et Cameroun, en période inter-épidémique. Aucun anticorps n'a été détecté dans les échantillons prélevés en période épidémique en RDC. La recherche de l'ARN du virus Ebola, au cours de ces études, était ...

Our knowledge on simian immune deficiency virus (SIV) diversity and evolution in the different nonhuman primate species is still incomplete. In this study, we report the full genome characterization of a new SIV from a red-tailed monkey (2013DRC-I8), from the Cercopithecus ascanius whitesidei subspecies, in the Democratic Republic of Congo (DRC). The new full-length genome is 9,926 bp long, and the genomic structure is similar to that of other SIVs with the absence of vpx and vpu genes. The new SIVasc-13DRC-I8 strain fell within the Cercopithecus specific SIV lineage. SIVasc-13DRC-I8 and previously reported SIVrtg from the C.a. schmidti subspecies in Uganda did not form a separate species-specific SIV lineage. These observations provide additional evidence for high genetic diversity and the complex evolution of SIVs in the Cercopithecus genus. More studies on a large number of monkeys from a wider geographic area are needed to understand SIV evolution.

Like the majority of emerging infectious diseases, HIV and HTLV are of zoonotic origin. Here we assess the risk of cross-species transmissions of their simian counterparts, SIV and STLV, from nonhuman primates (NHP) to humans in the Democratic Republic of Congo (DRC). A total of 331 samples, derived from NHP bushmeat, were collected as dried blood spots (DBS, n=283) or as tissue samples (n=36) at remote forest sites in northern and eastern DRC. SIV antibody prevalences in DBS were estimated with a novel high throughput immune assay with antigens representing the actual known diversity of HIV/SIV lineages. Antibody positive samples were confirmed by PCR and sequence analysis. Screening for STLV infection was done with universal primers in tax and new strains were further characterized in LTR. SIV and STLV infection in tissue samples was done by PCR only. Overall, 5% and 15.4% of NHP bushmeat was infected with SIV and STLV respectively. A new SIV lineage was identified in Allen's swamp monkeys (Allenopithecus nigroviridis). Three new STLV-1 subtypes were identified in Allen's swamp monkeys (Allenopithecus nigroviridis), blue monkeys (Cercopithecus mitis), red tailed guenons (Cercopithecus ascanius schmidti) and agile mangabeys (Cercocebus agilis). SIV and STLV prevalences varied according to species and geographic region. Our study illustrates clearly, even on a small sample size from a limited number of geograhic areas, that our knowledge on the genetic diversity and geographic distribution of simian retroviruses is still limited and that humans continue to be exposed to relative high proportions on infected NHP bushmeat.

Four types of human T cell lymphotropic viruses (HTLV) have been described (HTLV-1 to HTLV-4) with three of them having closely related simian virus analogues named STLV-1, −2, and −3. To assess the risk of cross-species transmissions of STLVs from nonhuman primates to humans in the Democratic Republic of Congo, a total of 330 samples, derived from primate bushmeat, were collected at remote forest sites where people rely on bushmeat for subsistence. STLV prevalences and genetic diversity were estimated by PCR and sequence analysis of tax-rex and LTR fragments. Overall, 7.9% of nonhuman primate bushmeat is infected with STLVs. We documented new STLV-1 and STLV-3 variants in six out of the seven species tested and showed for the first time STLV infection in C. mona wolfi, C. ascanius whitesidei, L. aterrimus aterrimus, C. angolensis, and P. tholloni. Our results provide increasing evidence that the diversity and geographic distribution of PTLVs are much greater than previously thought.

The recent large outbreaks of Ebola virus disease (EVD) in West Africa and the Democratic Republic of the Congo (DRC) have highlighted the need for rapid diagnostic tests to control this disease. In this study, we clinically evaluated a previously developed immunochromatography-based kit, QuickNavi(TM)-Ebola. During the 2018 outbreaks in DRC, 928 blood samples from EVD-suspected cases were tested with QuickNavi(TM)-Ebola and the WHO-approved GeneXpert. The sensitivity and specificity of QuickNavi(TM)-Ebola, estimated by comparing it to GeneXpert-confirmed cases, were 85% (68/80) and 99.8% (846/848), respectively. These results indicate the practical reliability of QuickNavi(TM)-Ebola for point-of-care diagnosis of EVD.

The recent large outbreaks of Ebola virus disease (EVD) in West Africa and the Democratic Republic of the Congo (DRC) have highlighted the need for rapid diagnostic tests to control this disease. In this study, we clinically evaluated a previously developed immunochromatography-based kit, QuickNavi(TM)-Ebola. During the 2018 outbreaks in DRC, 928 blood samples from EVD-suspected cases were tested with QuickNavi(TM)-Ebola and the WHO-approved GeneXpert. The sensitivity and specificity of QuickNavi(TM)-Ebola, estimated by comparing it to GeneXpert-confirmed cases, were 85% (68/80) and 99.8% (846/848), respectively. These results indicate the practical reliability of QuickNavi(TM)-Ebola for point-of-care diagnosis of EVD.

With 12 of the 31 outbreaks, the Democratic Republic of Congo (DRC) is highly affected by Ebolavirus disease (EVD). To better understand the role of bats in the ecology of Ebola viruses, we conducted surveys in bats during two recent EVD outbreaks and in two areas with previous outbreaks. Dried blood spots were tested for antibodies to ebolaviruses and oral and rectal swabs were screened for the presence of filovirus using a broadly reactive semi-nested RT-PCR. Between 2018 and 2020, 892 (88.6%) frugivorous and 115 (11.4%) insectivorous bats were collected. Overall, 11/925 (1.2%) to 100/925 (10.8%) bats showed antibodies to at least one Ebolavirus antigen depending on the positivity criteria. Antibodies were detected in fruit bats from the four sites and from species previously documented to harbor Ebola antibodies or RNA. We tested for the first time a large number of bats during ongoing EVD outbreaks in DRC, but no viral RNA was detected in the 676 sampled bats. Our study illustrates the difficulty to document the role of bats as a source of Ebolaviruses as they might clear quickly the virus. Given the increasing frequency of EVD outbreaks, more studies on the animal reservoir are urgently needed.

International audience ; With 12 of the 31 outbreaks, the Democratic Republic of Congo (DRC) is highly affected by Ebolavirus disease (EVD). To better understand the role of bats in the ecology of Ebola viruses, we conducted surveys in bats during two recent EVD outbreaks and in two areas with previous outbreaks. Dried blood spots were tested for antibodies to ebolaviruses and oral and rectal swabs were screened for the presence of filovirus using a broadly reactive semi-nested RT-PCR. Between 2018 and 2020, 892 (88.6%) frugivorous and 115 (11.4%) insectivorous bats were collected. Overall, 11/925 (1.2%) to 100/925 (10.8%) bats showed antibodies to at least one Ebolavirus antigen depending on the positivity criteria. Antibodies were detected in fruit bats from the four sites and from species previously documented to harbor Ebola antibodies or RNA. We tested for the first time a large number of bats during ongoing EVD outbreaks in DRC, but no viral RNA was detected in the 676 sampled bats. Our study illustrates the difficulty to document the role of bats as a source of Ebolaviruses as they might clear quickly the virus. Given the increasing frequency of EVD outbreaks, more studies on the animal reservoir are urgently needed.

International audience ; With 12 of the 31 outbreaks, the Democratic Republic of Congo (DRC) is highly affected by Ebolavirus disease (EVD). To better understand the role of bats in the ecology of Ebola viruses, we conducted surveys in bats during two recent EVD outbreaks and in two areas with previous outbreaks. Dried blood spots were tested for antibodies to ebolaviruses and oral and rectal swabs were screened for the presence of filovirus using a broadly reactive semi-nested RT-PCR. Between 2018 and 2020, 892 (88.6%) frugivorous and 115 (11.4%) insectivorous bats were collected. Overall, 11/925 (1.2%) to 100/925 (10.8%) bats showed antibodies to at least one Ebolavirus antigen depending on the positivity criteria. Antibodies were detected in fruit bats from the four sites and from species previously documented to harbor Ebola antibodies or RNA. We tested for the first time a large number of bats during ongoing EVD outbreaks in DRC, but no viral RNA was detected in the 676 sampled bats. Our study illustrates the difficulty to document the role of bats as a source of Ebolaviruses as they might clear quickly the virus. Given the increasing frequency of EVD outbreaks, more studies on the animal reservoir are urgently needed.

International audience ; With 12 of the 31 outbreaks, the Democratic Republic of Congo (DRC) is highly affected by Ebolavirus disease (EVD). To better understand the role of bats in the ecology of Ebola viruses, we conducted surveys in bats during two recent EVD outbreaks and in two areas with previous outbreaks. Dried blood spots were tested for antibodies to ebolaviruses and oral and rectal swabs were screened for the presence of filovirus using a broadly reactive semi-nested RT-PCR. Between 2018 and 2020, 892 (88.6%) frugivorous and 115 (11.4%) insectivorous bats were collected. Overall, 11/925 (1.2%) to 100/925 (10.8%) bats showed antibodies to at least one Ebolavirus antigen depending on the positivity criteria. Antibodies were detected in fruit bats from the four sites and from species previously documented to harbor Ebola antibodies or RNA. We tested for the first time a large number of bats during ongoing EVD outbreaks in DRC, but no viral RNA was detected in the 676 sampled bats. Our study illustrates the difficulty to document the role of bats as a source of Ebolaviruses as they might clear quickly the virus. Given the increasing frequency of EVD outbreaks, more studies on the animal reservoir are urgently needed.

Ten days after the declaration of the Ebola outbreak in the Democratic Republic of Congo, rapid identification of the species Zaire Ebola virus using partial gene amplification and nanopore sequencing backed up the use of the recombinant vesicular stomatitis virus–Zaire Ebola virus vaccine in the recommended ring vaccination strategy.

Ten days after the declaration of the Ebola outbreak in the Democratic Republic of Congo, rapid identification of the species Zaire Ebola virus using partial gene amplification and nanopore sequencing backed up the use of the recombinant vesicular stomatitis virus-Zaire Ebola virus vaccine in the recommended ring vaccination strategy.

International audience ; Background Epidemic arbovirus transmission occurs among humans by mosquito bites and the sylvatic transmission cycles involving non-human primates (NHPs) still exists. However, limited data are available on the extent in NHPs infections and their role. In this study, we have developed and validated a high-throughput serological screening tool to study the circulation of multiple arboviruses that represent a significant threat to human health, in NHPs in Central Africa.Methodology/Principal findings Recombinant proteins NS1, envelope domain-3 (DIII) for the dengue (DENV), yellow fever (YFV), usutu (USUV), west nile (WNV) and zika (ZIKV) and envelope 2 for the chikungunya (CHIKV) and o'nyong-nyong (ONNV) were coupled to Luminex beads to detect IgG directed against these viruses. Evaluation of test performance was made using 161 human sera of known arboviral status (66 negative and 95 positive). The sensitivity and specificity of each antigen were determined by statistical methods and ROC curves (except for ONNV and USUV). All NS1 antigens (except NS1-YFV), CHIKV-E2 and WNV-DIII had sensitivities and specificities > 95%. For the other DIII antigens, the sensitivity was low, limiting the interest of their use for seroprevalence studies. Few simultaneous reactions were observed between the CHIKV+ samples and the NS1 antigens to the non-CHIKV arboviruses. On the other hand, the DENV+ samples crossed-reacted with NS1 of all the DENV serotypes (1 to 4), as well as with ZIKV, USUV and to a lesser extent with YFV. A total of 3,518 samples of 29 species of NHPs from Cameroon and the Democratic Republic of Congo (DRC) were tested against NS1 (except YFV), E2 (CHIKV/ONNV) and DIII (WNV) antigens. In monkeys (n = 2,100), the global prevalence varied between 2 and 5% for the ten antigens tested. When we stratified by monkey's biotope, the arboreal species showed the highest reactivity. In monkeys from Cameroon, the highest IgG prevalence were observed against ONNV-E2 and DENV2-NS1 with 3.95% and ...