Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 268
Filtrar
2.
Emerg Infect Dis ; 30(4): 761-765, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38526165

RESUMEN

In September 2022, deaths of pigs manifesting pox-like lesions caused by swinepox virus were reported in Tshuapa Province, Democratic Republic of the Congo. Two human mpox cases were found concurrently in the surrounding community. Specific diagnostics and robust sequencing are needed to characterize multiple poxviruses and prevent potential poxvirus transmission.


Asunto(s)
Mpox , Poxviridae , Suipoxvirus , Humanos , Animales , Porcinos , Mpox/epidemiología , Monkeypox virus/genética , República Democrática del Congo/epidemiología
3.
Lancet Microbe ; 5(2): e109-e118, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38278165

RESUMEN

BACKGROUND: The Democratic Republic of the Congo has had 15 Ebola virus disease (EVD) outbreaks, from 1976 to 2023. On June 1, 2020, the Democratic Republic of the Congo declared an outbreak of EVD in the western Équateur Province (11th outbreak), proximal to the 2018 Tumba and Bikoro outbreak and concurrent with an outbreak in the eastern Nord Kivu Province. In this Article, we assessed whether the 11th outbreak was genetically related to previous or concurrent EVD outbreaks and connected available epidemiological and genetic data to identify sources of possible zoonotic spillover, uncover additional unreported cases of nosocomial transmission, and provide a deeper investigation into the 11th outbreak. METHODS: We analysed epidemiological factors from the 11th EVD outbreak to identify patient characteristics, epidemiological links, and transmission modes to explore virus spread through space, time, and age groups in the Équateur Province, Democratic Republic of the Congo. Trained field investigators and health professionals recorded data on suspected, probable, and confirmed cases, including demographic characteristics, possible exposures, symptom onset and signs and symptoms, and potentially exposed contacts. We used blood samples from individuals who were live suspected cases and oral swabs from individuals who were deceased to diagnose EVD. We applied whole-genome sequencing of 87 available Ebola virus genomes (from 130 individuals with EVD between May 19 and Sept 16, 2020), phylogenetic divergence versus time, and Bayesian reconstruction of phylogenetic trees to calculate viral substitution rates and study viral evolution. We linked the available epidemiological and genetic datasets to conduct a genomic and epidemiological study of the 11th EVD outbreak. FINDINGS: Between May 19 and Sept 16, 2020, 130 EVD (119 confirmed and 11 probable) cases were reported across 13 Équateur Province health zones. The individual identified as the index case reported frequent consumption of bat meat, suggesting the outbreak started due to zoonotic spillover. Sequencing revealed two circulating Ebola virus variants associated with this outbreak-a Mbandaka variant associated with the majority (97%) of cases and a Tumba-like variant with similarity to the ninth EVD outbreak in 2018. The Tumba-like variant exhibited a reduced substitution rate, suggesting transmission from a previous survivor of EVD. INTERPRETATION: Integrating genetic and epidemiological data allowed for investigative fact-checking and verified patient-reported sources of possible zoonotic spillover. These results demonstrate that rapid genetic sequencing combined with epidemiological data can inform responders of the mechanisms of viral spread, uncover novel transmission modes, and provide a deeper understanding of the outbreak, which is ultimately needed for infection prevention and control during outbreaks. FUNDING: WHO and US Centers for Disease Control and Prevention.


Asunto(s)
Ebolavirus , Fiebre Hemorrágica Ebola , Estados Unidos , Humanos , Animales , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/prevención & control , Estudios Retrospectivos , República Democrática del Congo/epidemiología , Filogenia , Teorema de Bayes , Ebolavirus/genética , Brotes de Enfermedades , Genómica , Zoonosis/epidemiología
4.
AIDS Res Hum Retroviruses ; 40(3): 181-187, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37335033

RESUMEN

Type-1 HIV (HIV-1) group M (HIV-1M) genetic diversity is highest in the Congo Basin where the epidemic ignited a century ago. HIV-1M has diversified into multiple subtypes, sub-subtypes, and circulating and unique recombinant forms (CRFs/URFs). An unanswered question is why some rare subtypes never reached epidemic levels despite their age. Several studies identified the role of HIV-1M accessory genes nef and vpu in virus adaptation to human hosts and subsequent spread. Other reports also pointed out the pivotal role of gag in transmissibility, virulence, and replication capacity. In this study we characterized the HIV-1 gag gene of 148 samples collected in different localities of the Democratic Republic of the Congo (DRC) between 1997 and 2013. We used nested polymerase chain reaction (PCR) to amplify the whole gag gene. PCR products were sequenced either by Sanger method or by next generation sequencing on Illumina MiSeq or iSeq100 platforms. Generated sequences were used for subsequent analyses using different bioinformatic tools. Phylogenetic analysis of the generated sequences revealed a high genetic diversity with up to 22 different subtypes, sub-subtypes, CRFs. Up to 15% (22/148) URFs were identified, in addition to rare subtypes such as H, J, and K. At least two amino acid motifs present in the gag gene have been shown to modulate HIV-1 replication, budding, and fitness: the P(T/S)AP and the LYPXnL motifs. Structural analysis revealed the presence of P(T/S)AP in all the 148 sequences with the majority (136/148) bearing the PTAP. Three samples presented a duplication of this motif. The LYPXnL motif was identified in 38 of 148 sequences. There was no clear link between the frequency of these motifs and HIV-1M subtypes. In summary, we confirmed a high genetic diversity of HIV-1M in the DRC. We observed the presence of amino acid motifs important for viral replication and budding even in some rare HIV-1 subtypes. Their impact on viral fitness needs be further evaluated by in vitro studies.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , VIH-1 , Humanos , República Democrática del Congo/epidemiología , Filogenia , VIH-1/genética , Genes gag/genética , Variación Genética
5.
Lancet Infect Dis ; 24(3): 266-274, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38043556

RESUMEN

BACKGROUND: The use of specific anti-Ebola virus therapy, especially monoclonal antibodies, has improved survival in patients with Ebola virus disease. We aimed to assess the effect of monoclonal antibodies on anti-Ebola virus antibody responses in survivors of the 2018-20 Ebola outbreak in the Democratic Republic of the Congo. METHODS: In this observational prospective cohort study, participants were enrolled at three Ebola survivor clinics in Beni, Mangina, and Butembo (Democratic Republic of the Congo). Eligible children and adults notified as survivors of Ebola virus disease (ie, who had confirmed Ebola virus disease [RT-PCR positive in blood sample] and were subsequently declared recovered from the virus [RT-PCR negative in blood sample] with a certificate of recovery from Ebola virus disease issued by an Ebola treatment centre) during the 2018-20 Ebola virus disease outbreak were invited to participate in the study. Participants were recruited on discharge from Ebola treatment centres and followed up for 12-18 months depending on recruitment date. Routine follow-up assessments were done at 1, 3, 6, and 12-18 months after inclusion. We collected sociodemographic (age, sex, visit site), clinical (anti-Ebola virus drugs), and laboratory data (RT-PCR and Ct values). The primary outcome was the antibody concentrations against Ebola virus glycoprotein, nucleoprotein, and 40-kDa viral protein antigens over time assessed in all participants. Antibody concentrations were measured by the multiplex immunoassay, and the association between anti-Ebola virus antibody levels and the relevant exposures, such as anti-Ebola virus disease drugs (ansuvimab, REGN-EB3, ZMapp, or remdesivir), was assessed using both linear and logistic mixed regression models. This study is registered at ClinicalTrials.gov, NCT04409405. FINDINGS: Between April 16, 2020, and Oct 18, 2021, 1168 survivors were invited to participate in the Les Vainqueurs d'Ebola cohort study. 787 survivors were included in the study, of whom 358 had data available for antibody responses. 85 (24%) of 358 were seronegative for at least two Ebola virus antigens on discharge from the Ebola treatment centre. The antibody response over time fluctuated but a continuous decrease in an overall linear evolution was observed. Quantitative modelling showed a decrease in nucleoprotein, glycoprotein, and VP-40 antibody concentrations over time (p<0·0001) with the fastest decrease observed for glycoprotein. The probability of being seropositive for at least two antigens after 36 months was 53·6% (95% CI 51·6-55·6) for participants who received ansuvimab, 73·5% (71·5-75·5) for participants who received REGN-EB3, 76·8% (74·8-78·8) for participants who received remdesivir, and 78·5% (76·5-80·5) for participants who received ZMapp. INTERPRETATION: Almost a quarter of survivors were seronegative on discharge from the Ebola treatment centre and antibody concentrations decreased rapidly over time. These results indicate that monoclonal antibodies might negatively affect the production of anti-Ebola virus antibodies in survivors of Ebola virus disease which could increase the risk of reinfection or reactivation. FUNDING: The French National Agency for AIDS Research-Emergent Infectious Diseases-The French National Institute of Health and Medical Research, the French National Research Institute for Development, and the European and Developing Countries Clinical Trials Partnership. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.


Asunto(s)
Ebolavirus , Fiebre Hemorrágica Ebola , Adulto , Niño , Humanos , Fiebre Hemorrágica Ebola/tratamiento farmacológico , Fiebre Hemorrágica Ebola/epidemiología , Formación de Anticuerpos , Estudios de Cohortes , Estudios Prospectivos , República Democrática del Congo/epidemiología , Anticuerpos Antivirales , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales/farmacología , Sobrevivientes , Glicoproteínas , Nucleoproteínas/farmacología , Nucleoproteínas/uso terapéutico
6.
Emerg Infect Dis ; 30(1): 172-176, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38019211

RESUMEN

We report a cluster of clade I monkeypox virus infections linked to sexual contact in the Democratic Republic of the Congo. Case investigations resulted in 5 reverse transcription PCR-confirmed infections; genome sequencing suggest they belonged to the same transmission chain. This finding demonstrates that mpox transmission through sexual contact extends beyond clade IIb.


Asunto(s)
Mpox , Humanos , Mpox/epidemiología , Monkeypox virus/genética , República Democrática del Congo/epidemiología , Reacción en Cadena de la Polimerasa/métodos
7.
Open Forum Infect Dis ; 10(12): ofad582, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38156046

RESUMEN

Background: A prospective study was extended to the new antiretroviral and monitoring strategies in HIV-infected adults in low-income countries (NAMSAL-ANRS)-12313 trial, a 96-week open-label, multicenter, randomized phase 3 trial comparing dolutegravir (DTG) 50 mg with efavirenz 400 mg (EFV400), both administered with tenofovir disoproxil fumarate and lamivudine (TDF/3TC) as first-line treatment for antiretroviral therapy (ART)-naive people living with human immunodeficiency virus type 1 (HIV). Noninferiority of DTG to EFV400 was demonstrated at 48-week and sustained at 96 weeks. Here, we present results at 192-week. Methods: Previous trial participants were reconsented and followed up on their initial randomization arm (1:1 DTG/TDF/3TC:EFV400/TDF/3TC). Assessments included changes in viral suppression, biological parameters, and new serious adverse events (SAEs). Results: Among the participants enrolled in the trial, 81% (499/613) were analyzed at week 192: 84% (261/310) on DTG/TDF/3TC and 78% (238/303) on EFV400/TDF/3TC. HIV RNA suppression was maintained in 69% (214/310) on DTG/TDF/3TC-based and 62% (187/303) on EFV400/TDF/3TC-based regimens (difference, 7.3% [95% confidence interval, -.20 to 14.83]; P = .057). Five (DTG/TDF/3TC = 2; EFV400/TDF/3TC = 3) new viral failures (World Health Organization definition) without related resistance DTG mutations and 24 new SAEs were observed (DTG/TDF/3TC = 13; EFV400/TDF/3TC = 11). Mean weight gain was +9.4 kg on DTG/TDF/3TC and +5.9 kg on EFV400/TDF/3TC. The percentage of participants with obesity increased from 6.9% to 27.7% on DTG/TDF/3TC (P < .0001) and from 8.3% to 16.7% on EFV400/TDF/3TC (P = .0033). Conclusions: Four-year follow-up of people with HIV on DTG- and EFV400-based regimens showed long-term efficacy and safety of both ARTs, markedly among participants on DTG/TDF/3TC with high baseline viral load. However, unexpected substantial weight gain over time was prominent among participants on DTG/TDF/3TC, which should be closely monitored. Clinical Trials Registration. NCT02777229.

8.
Viruses ; 15(11)2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38005934

RESUMEN

To estimate the prevalence of IgG antibodies against six arboviruses in people living with HIV-1 (PLWHIV) in Madagascar, we tested samples collected between January 2018 and June 2021. We used a Luminex-based serological assay to detect IgG antibodies against antigens from Dengue virus serotypes 1-4 (DENV1-4), Zika virus (ZIKV), West Nile virus (WNV), Usutu virus (USUV), Chikungunya virus (CHIKV), and O'nyong nyong virus (ONNV). Of the 1036 samples tested, IgG antibody prevalence was highest for ONNV (28.4%), CHIKV (26.7%), WNV-NS1 (27.1%), DENV1 (12.4%), USUV (9.9%), and DENV3 (8.9%). ZIKV (4.9%), DENV2 (4.6%), WNV-D3 (5.1%), and DENV4 (1.4%) were lower. These rates varied by province of origin, with the highest rates observed in Toamasina, on the eastern coast (50.5% and 56.8%, for CHIKV and ONNV, respectively). The seroprevalence increased with age for DENV1 and 3 (p = 0.006 and 0.038, respectively) and WNV DIII (p = 0.041). The prevalence of IgG antibodies against any given arborvirus varied over the year and significantly correlated with rainfalls in the different areas (r = 0.61, p = 0.036). Finally, we found a significant correlation between the seroprevalence of antibodies against CHIKV and ONNV and the HIV-1 RNA plasma viral load. Thus, PLWHIV in Madagascar are highly exposed to various arboviruses. Further studies are needed to explain some of our findings.


Asunto(s)
Arbovirus , Fiebre Chikungunya , Virus Chikungunya , Infecciones por VIH , Virus del Nilo Occidental , Infección por el Virus Zika , Virus Zika , Humanos , Infección por el Virus Zika/diagnóstico , Madagascar/epidemiología , Inmunoglobulina G , Estudios Seroepidemiológicos , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Anticuerpos Antivirales
9.
Viruses ; 15(9)2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37766333

RESUMEN

The seroprevalence to orthoebolaviruses was studied in 9594 bats (5972 frugivorous and 3622 insectivorous) from Cameroon, the Democratic Republic of Congo (DRC) and Guinea, with a Luminex-based serological assay including recombinant antigens of four orthoebolavirus species. Seroprevalence is expressed as a range according to different cut-off calculations. Between 6.1% and 18.9% bat samples reacted with at least one orthoebolavirus antigen; the highest reactivity was seen with Glycoprotein (GP) antigens. Seroprevalence varied per species and was higher in frugivorous than insectivorous bats; 9.1-27.5% versus 1.3-4.6%, respectively. Seroprevalence in male (13.5%) and female (14.4%) bats was only slightly different and was higher in adults (14.9%) versus juveniles (9.4%) (p < 0.001). Moreover, seroprevalence was highest in subadults (45.4%) when compared to mature adults (19.2%), (p < 0.001). Our data suggest orthoebolavirus circulation is highest in young bats. More long-term studies are needed to identify birthing pulses for the different bat species in diverse geographic regions and to increase the chances of detecting viral RNA in order to document the genetic diversity of filoviruses in bats and their pathogenic potential for humans. Frugivorous bats seem more likely to be reservoirs of orthoebolaviruses, but the role of insectivorous bats has also to be further examined.

10.
Pathogens ; 12(7)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37513764

RESUMEN

Human Mpox cases are increasingly reported in Africa, with the highest burden in the Democratic Republic of Congo (DRC). While case reporting on a clinical basis can overestimate infection rates, laboratory confirmation by PCR can underestimate them, especially on suboptimal samples like blood, commonly used in DRC. Here we used a Luminex-based assay to evaluate whether antibody testing can be complementary to confirm cases and to identify human transmission chains during outbreak investigations. We used left-over blood samples from 463 patients, collected during 174 outbreaks between 2013 and 2022, with corresponding Mpox and VZV PCR results. In total, 157 (33.9%) samples were orthopox-PCR positive and classified as Mpox+; 124 (26.8%) had antibodies to at least one of the three Mpox peptides. The proportion of antibody positive samples was significantly higher in Mpox positive samples (36.9%) versus negative (21.6%) (p < 0.001). By combining PCR and serology, 66 additional patients were identified, leading to an Mpox infection rate of 48.2% (223/463) versus 33.9% when only PCR positivity is considered. Mpox infections were as such identified in 14 additional health zones and 23 additional outbreaks (111/174 (63.8%) versus 88/174 (50.6%)). Our findings highlight the urgent need of rapid on-site diagnostics to circumvent Mpox spread.

11.
Open Forum Infect Dis ; 10(5): ofad216, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37152188

RESUMEN

Background: We aimed to estimate the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seroprevalence among the general population in Conakry, Guinea and Yaounde, Cameroon after the coronavirus disease 2019 Omicron wave. Methods: We conducted population-based, age-stratified seroprevalence surveys in Conakry and Yaounde (May and June 2022). We collected demographic and epidemiologic information and dried blood spot samples that were tested for SARS-CoV-2 immunoglobulin G (IgG) antibodies using recombinant nucleocapsid and spike proteins with Luminex technology. Results: Samples were obtained from 1386 and 1425 participants in Guinea and Cameroon, respectively. The overall age-standardized SARS-CoV-2 IgG seroprevalence against spike and nucleocapsid proteins was 71.57% (95% confidence interval [CI], 67.48%-75.33%) in Guinea and 74.71% (95% CI, 71.99%-77.25%) in Cameroon. Seroprevalence increased significantly with age categories. Female participants were more likely than male participants to be seropositive. The seroprevalence in unvaccinated participants was 69.6% (95% CI, 65.5%-73.41%) in Guinea and 74.8% (95% CI, 72.04%-77.38%) in Cameroon. In multivariate analysis, only age, sex, and education were independently associated with seropositivity. Conclusions: These findings show a high community transmission after the different epidemiological waves including Omicron, especially among people aged >40 years. In addition, our results suggest that the spread of SARS-CoV-2 has been underestimated as a significant proportion of the population has already contracted the virus and that vaccine strategies should focus on vulnerable populations.

12.
Nat Microbiol ; 8(6): 1039-1050, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37169918

RESUMEN

Humans and other primates harbour complex gut bacterial communities that influence health and disease, but the evolutionary histories of these symbioses remain unclear. This is partly due to limited information about the microbiota of ancestral primates. Here, using phylogenetic analyses of metagenome-assembled genomes (MAGs), we show that hundreds of gut bacterial clades diversified in parallel (that is, co-diversified) with primate species over millions of years, but that humans have experienced widespread losses of these ancestral symbionts. Analyses of 9,460 human and non-human primate MAGs, including newly generated MAGs from chimpanzees and bonobos, revealed significant co-diversification within ten gut bacterial phyla, including Firmicutes, Actinobacteriota and Bacteroidota. Strikingly, ~44% of the co-diversifying clades detected in African apes were absent from available metagenomic data from humans and ~54% were absent from industrialized human populations. In contrast, only ~3% of non-co-diversifying clades detected in African apes were absent from humans. Co-diversifying clades present in both humans and chimpanzees displayed consistent genomic signatures of natural selection between the two host species but differed in functional content from co-diversifying clades lost from humans, consistent with selection against certain functions. This study discovers host-species-specific bacterial symbionts that predate hominid diversification, many of which have undergone accelerated extinctions from human populations.


Asunto(s)
Microbioma Gastrointestinal , Hominidae , Animales , Humanos , Filogenia , Pan troglodytes , Primates , Hominidae/microbiología , Bacterias/genética
13.
Trop Med Int Health ; 28(7): 508-516, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37243412

RESUMEN

BACKGROUND: Many SARS-CoV-2 seroprevalence surveys since the end of 2020 have disqualified the first misconception that Africa had been spared by the pandemic. Through the analysis of three SARS-CoV-2 seroprevalence surveys carried out in Benin as part of the ARIACOV project, we argue that the integration of epidemiological serosurveillance of the SARS-CoV-2 infection in the national surveillance packages would be of great use to refine the understanding of the COVID-19 pandemic in Africa. METHODS: We carried out three repeated cross-sectional surveys in Benin: two in Cotonou, the economic capital in March and May 2021, and one in Natitingou, a semi-rural city in the north of the country in August 2021. Total and weighted-by-age-group seroprevalences were estimated and the risk factors for SARS-CoV-2 infection were assessed by multivariate logistic regression. RESULTS: In Cotonou, a slight increase in overall age-standardised SARS-CoV-2 seroprevalence from 29.77% (95% CI: 23.12%-37.41%) at the first survey to 34.86% (95% CI: 31.57%-38.30%) at the second survey was observed. In Natitingou, the globally adjusted seroprevalence was 33.34% (95% CI: 27.75%-39.44%). A trend of high risk for SARS-CoV 2 seropositivity was observed in adults over 40 versus the young (less than 18 years old) during the first survey in Cotonou but no longer in the second survey. CONCLUSIONS: Our results show that, however, rapid organisation of preventive measures aimed at breaking the chains of transmission, they were ultimately unable to prevent a wide spread of the virus in the population. Routine serological surveillance on strategic sentinel sites and/or populations could constitute a cost-effective compromise to better anticipate the onset of new waves and define public health strategies.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Adolescente , Benin/epidemiología , COVID-19/epidemiología , Pandemias , Estudios Transversales , Estudios Seroepidemiológicos , Anticuerpos Antivirales
14.
Viruses ; 15(2)2023 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-36851551

RESUMEN

Bats are at the origin of human coronaviruses, either directly or via an intermediate host. We tested swabs from 4597 bats (897 from the Democratic Republic of Congo (DRC), 2191 from Cameroon and 1509 from Guinea) with a broadly reactive PCR in the RdRp region. Coronaviruses were detected in 903 (19.6%) bats and in all species, with more than 25 individuals tested. The highest prevalence was observed in Eidolon helvum (239/733; 39.9%) and Rhinolophus sp. (306/899; 34.1%), followed by Hipposideros sp. (61/291; 20.9%). Frugivorous bats were predominantly infected with beta coronaviruses from the Nobecovirus subgenus (93.8%), in which at least 6 species/genus-specific subclades were observed. In contrast, insectivorous bats were infected with beta-coronaviruses from different subgenera (Nobecovirus (8.5%), Hibecovirus (32.8%), Merbecovirus (0.5%) and Sarbecovirus (57.6%)) and with a high diversity of alpha-coronaviruses. Overall, our study shows a high prevalence and genetic diversity of coronaviruses in bats and illustrates that Rhinolophus bats in Africa are infected at high levels with the Sarbecovirus subgenus, to which SARS-CoV-2 belongs. It is important to characterize in more detail the different coronavirus lineages from bats for their potential to infect human cells, their evolution and to study frequency and modes of contact between humans and bats in Africa.


Asunto(s)
Quirópteros , Coronavirus , Animales , Camerún , Quirópteros/virología , Coronavirus/aislamiento & purificación
15.
Nat Commun ; 14(1): 1033, 2023 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-36823144

RESUMEN

The malaria parasite Plasmodium falciparum causes substantial human mortality, primarily in equatorial Africa. Enriched in affected African populations, the B*53 variant of HLA-B, a cell surface protein that presents peptide antigens to cytotoxic lymphocytes, confers protection against severe malaria. Gorilla, chimpanzee, and bonobo are humans' closest living relatives. These African apes have HLA-B orthologs and are infected by parasites in the same subgenus (Laverania) as P. falciparum, but the consequences of these infections are unclear. Laverania parasites infect bonobos (Pan paniscus) at only one (TL2) of many sites sampled across their range. TL2 spans the Lomami River and has genetically divergent subpopulations of bonobos on each side. Papa-B, the bonobo ortholog of HLA-B, includes variants having a B*53-like (B07) peptide-binding supertype profile. Here we show that B07 Papa-B occur at high frequency in TL2 bonobos and that malaria appears to have independently selected for different B07 alleles in the two subpopulations.


Asunto(s)
Antígenos de Histocompatibilidad Clase I , Malaria Falciparum , Pan paniscus , Plasmodium , Animales , Malaria Falciparum/genética , Pan paniscus/genética , Pan paniscus/parasitología , Péptidos , Filogenia , Antígenos de Histocompatibilidad Clase I/genética
16.
Genome Biol ; 23(1): 212, 2022 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-36224660

RESUMEN

Earth's environments harbor complex consortia of microbes that affect processes ranging from host health to biogeochemical cycles. Understanding their evolution and function is limited by an inability to isolate genomes in a high-throughput manner. Here, we present a workflow for bacterial whole-genome sequencing using open-source labware and the OpenTrons robotics platform, reducing costs to approximately $10 per genome. We assess genomic diversity within 45 gut bacterial species from wild-living chimpanzees and bonobos. We quantify intraspecific genomic diversity and reveal divergence of homologous plasmids between hosts. This enables population genetic analyses of bacterial strains not currently possible with metagenomic data alone.


Asunto(s)
Genoma Bacteriano , Microbiota , Animales , Bacterias/genética , Genómica , Metagenoma , Microbiota/genética , Pan troglodytes/genética , Filogenia , Flujo de Trabajo
17.
Commun Biol ; 5(1): 1020, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-36167977

RESUMEN

Chimpanzees (Pan troglodytes) harbor rich assemblages of malaria parasites, including three species closely related to P. falciparum (sub-genus Laverania), the most malignant human malaria parasite. Here, we characterize the ecology and epidemiology of malaria infection in wild chimpanzee reservoirs. We used molecular assays to screen chimpanzee fecal samples, collected longitudinally and cross-sectionally from wild populations, for malaria parasite mitochondrial DNA. We found that chimpanzee malaria parasitism has an early age of onset and varies seasonally in prevalence. A subset of samples revealed Hepatocystis mitochondrial DNA, with phylogenetic analyses suggesting that Hepatocystis appears to cross species barriers more easily than Laverania. Longitudinal and cross-sectional sampling independently support the hypothesis that mean ambient temperature drives spatiotemporal variation in chimpanzee Laverania infection. Infection probability peaked at ~24.5 °C, consistent with the empirical transmission optimum of P. falciparum in humans. Forest cover was also positively correlated with spatial variation in Laverania prevalence, consistent with the observation that forest-dwelling Anophelines are the primary vectors. Extrapolating these relationships across equatorial Africa, we map spatiotemporal variation in the suitability of chimpanzee habitat for Laverania transmission, offering a hypothetical baseline indicator of human exposure risk.


Asunto(s)
Hominidae , Malaria Falciparum , Malaria , Plasmodium , Animales , Estudios Transversales , ADN Mitocondrial/genética , Humanos , Malaria/epidemiología , Malaria/parasitología , Malaria/veterinaria , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Pan troglodytes/genética , Filogenia , Plasmodium/genética
18.
Viruses ; 14(8)2022 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-36016364

RESUMEN

In West Africa, research on the hepatitis E virus (HEV) is barely covered, despite the recorded outbreaks. The low level of access to safe water and adequate sanitation is still one of the main factors of HEV spread in developing countries. HEV infection induces acute or sub-clinical liver diseases with a mortality rate ranging from 0.5 to 4%. The mortality rate is more alarming (15 to 25%) among pregnant women, especially in the last trimester of pregnancy. Herein, we conducted a multicentric socio-demographic and seroepidemiological survey of HEV in Senegal among pregnant women. A consecutive and non-redundant recruitment of participants was carried out over the period of 5 months, from March to July 2021. A total of 1227 consenting participants attending antenatal clinics responded to a standard questionnaire. Plasma samples were collected and tested for anti-HEV IgM and IgG by using the WANTAI HEV-IgM and IgG ELISA assay. The overall HEV seroprevalence was 7.8% (n = 96), with 0.5% (n = 6) and 7.4% (n = 91) for HEV IgM and HEV IgG, respectively. One of the participant samples was IgM/IgG-positive, while four were declared indeterminate to anti-HEV IgM as per the manufacturer's instructions. From one locality to another, the seroprevalence of HEV antibodies varied from 0 to 1% for HEV IgM and from 1.5 to 10.5% for HEV IgG. The data also showed that seroprevalence varied significantly by marital status (p < 0.0001), by the regularity of income (p = 0.0043), and by access to sanitation services (p = 0.0006). These data could serve as a basis to setup national prevention strategies focused on socio-cultural, environmental, and behavioral aspects for a better management of HEV infection in Senegal.


Asunto(s)
Virus de la Hepatitis E , Hepatitis E , Femenino , Anticuerpos Antihepatitis , Humanos , Inmunoglobulina G , Inmunoglobulina M , Embarazo , Mujeres Embarazadas , Derivación y Consulta , Factores de Riesgo , Senegal/epidemiología , Estudios Seroepidemiológicos
19.
Open Forum Infect Dis ; 9(5): ofac152, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35493112

RESUMEN

We conducted 3 successive seroprevalence surveys, 3 months apart, using multistage cluster sampling to measure the extent and dynamics of the severe acute respiratory syndrome coronavirus 2 epidemic in Conakry, the capital city of Guinea. Seroprevalence increased from 17.3% (95% CI, 12.4%-23.8%) in December 2020 during the first survey (S1) to 28.9% (95% CI, 25.6%-32.4%) in March/April 2021 (S2), then to 42.4% (95% CI, 39.5%-45.3%) in June 2021 (S3). This significant overall trend of increasing seroprevalence (P < .0001) was also significant in every age class, illustrating a sustained transmission within the whole community. These data may contribute to defining cost-effective response strategies.

20.
Viruses ; 14(4)2022 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-35458511

RESUMEN

BACKGROUND: Studies have linked bats to outbreaks of viral diseases in human populations such as SARS-CoV-1 and MERS-CoV and the ongoing SARS-CoV-2 pandemic. METHODS: We carried out a longitudinal survey from August 2020 to July 2021 at two sites in Zimbabwe with bat-human interactions: Magweto cave and Chirundu farm. A total of 1732 and 1866 individual bat fecal samples were collected, respectively. Coronaviruses and bat species were amplified using PCR systems. RESULTS: Analysis of the coronavirus sequences revealed a high genetic diversity, and we identified different sub-viral groups in the Alphacoronavirus and Betacoronavirus genus. The established sub-viral groups fell within the described Alphacoronavirus sub-genera: Decacovirus, Duvinacovirus, Rhinacovirus, Setracovirus and Minunacovirus and for Betacoronavirus sub-genera: Sarbecoviruses, Merbecovirus and Hibecovirus. Our results showed an overall proportion for CoV positive PCR tests of 23.7% at Chirundu site and 16.5% and 38.9% at Magweto site for insectivorous bats and Macronycteris gigas, respectively. CONCLUSIONS: The higher risk of bat coronavirus exposure for humans was found in December to March in relation to higher viral shedding peaks of coronaviruses in the parturition, lactation and weaning months of the bat populations at both sites. We also highlight the need to further document viral infectious risk in human/domestic animal populations surrounding bat habitats in Zimbabwe.


Asunto(s)
Alphacoronavirus , COVID-19 , Quirópteros , Animales , COVID-19/epidemiología , Evolución Molecular , Femenino , Genoma Viral , Filogenia , SARS-CoV-2/genética , Zimbabwe/epidemiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...