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Showing papers by "Nicole Vidal published in 2019"


Journal ArticleDOI
TL;DR: The distribution of HIV-1 subtypes and recombinants changed over time in countries, regions, and globally as well as at a global level during 2005-15, where subtype B increased, subtypes A and D were stable, and subtypes C and G and CRF02_AG decreased.
Abstract: Summary Background Global genetic diversity of HIV-1 is a major challenge to the development of HIV vaccines. We aimed to estimate the regional and global distribution of HIV-1 subtypes and recombinants during 1990–2015. Methods We searched PubMed, EMBASE (Ovid), CINAHL (Ebscohost), and Global Health (Ovid) for HIV-1 subtyping studies published between Jan 1, 1990, and Dec 31, 2015. We collected additional unpublished HIV-1 subtyping data through a global survey. We included prevalence studies with HIV-1 subtyping data collected during 1990–2015. We grouped countries into 14 regions and analysed data for four time periods (1990–99, 2000–04, 2005–09, and 2010–15). The distribution of HIV-1 subtypes, circulating recombinant forms (CRFs), and unique recombinant forms (URFs) in individual countries was weighted according to the UNAIDS estimates of the number of people living with HIV (PLHIV) in each country to generate regional and global estimates of HIV-1 diversity in each time period. The primary outcome was the number of samples designated as HIV-1 subtypes A, B, C, D, F, G, H, J, K, CRFs, and URFs. The systematic review is registered with PROSPERO, number CRD42017067164. Findings This systematic review and global survey yielded 2203 datasets with 383 519 samples from 116 countries in 1990–2015. Globally, subtype C accounted for 46·6% (16 280 897/34 921 639 of PLHIV) of all HIV-1 infections in 2010–15. Subtype B was responsible for 12·1% (4 235 299/34 921 639) of infections, followed by subtype A (10·3%; 3 587 003/34 921 639), CRF02_AG (7·7%; 2 705 110/34 921 639), CRF01_AE (5·3%; 1 840 982/34 921 639), subtype G (4·6%; 1 591 276/34 921 639), and subtype D (2·7%; 926 255/34 921 639). Subtypes F, H, J, and K combined accounted for 0·9% (311 332/34 921 639) of infections. Other CRFs accounted for 3·7% (1 309 082/34 921 639), bringing the proportion of all CRFs to 16·7% (5 844 113/34 921 639). URFs constituted 6·1% (2 134 405/34 921 639), resulting in recombinants accounting for 22·8% (7 978 517/34 921 639) of all global HIV-1 infections. The distribution of HIV-1 subtypes and recombinants changed over time in countries, regions, and globally. At a global level during 2005–15, subtype B increased, subtypes A and D were stable, and subtypes C and G and CRF02_AG decreased. CRF01_AE, other CRFs, and URFs increased, leading to a consistent increase in the global proportion of recombinants over time. Interpretation Global and regional HIV diversity is complex and evolving, and is a major challenge to HIV vaccine development. Surveillance of the global molecular epidemiology of HIV-1 remains crucial for the design, testing, and implementation of HIV vaccines. Funding None.

189 citations


Journal ArticleDOI
TL;DR: The real-time generation of genomic information at the start of the 2018 Ebola virus disease (EVD) outbreak in North Kivu Province demonstrated that the EVD outbreak in the North KIVu and Ituri Provinces was distinct from the 2018 EVD outbreaks in Équateur Province of the Democratic Republic of the Congo.
Abstract: Summary Background The real-time generation of information about pathogen genomes has become a vital goal for transmission analysis and characterisation in rapid outbreak responses. In response to the recently established genomic capacity in the Democratic Republic of the Congo, we explored the real-time generation of genomic information at the start of the 2018 Ebola virus disease (EVD) outbreak in North Kivu Province. Methods We used targeted-enrichment sequencing to produce two coding-complete Ebola virus genomes 5 days after declaration of the EVD outbreak in North Kivu. Subsequent sequencing efforts yielded an additional 46 genomes. Genomic information was used to assess early transmission, medical countermeasures, and evolution of Ebola virus. Findings The genomic information demonstrated that the EVD outbreak in the North Kivu and Ituri Provinces was distinct from the 2018 EVD outbreak in Equateur Province of the Democratic Republic of the Congo. Primer and probe mismatches to Ebola virus were identified in silico for all deployed diagnostic PCR assays, with the exception of the Cepheid GeneXpert GP assay. Interpretation The first two coding-complete genomes provided actionable information in real-time for the deployment of the rVSVΔG-ZEBOV-GP Ebola virus envelope glycoprotein vaccine, available therapeutics, and sequence-based diagnostic assays. Based on the mutations identified in the Ebola virus surface glycoprotein (GP12) observed in all 48 genomes, deployed monoclonal antibody therapeutics (mAb114 and ZMapp) should be efficacious against the circulating Ebola virus variant. Rapid Ebola virus genomic characterisation should be included in routine EVD outbreak response procedures to ascertain efficacy of medical countermeasures. Funding Defense Biological Product Assurance Office.

54 citations


Journal ArticleDOI
TL;DR: Ten days after the declaration of the Ebola outbreak in the Democratic Republic of Congo, rapid identification of the species Zaires 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.
Abstract: 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.

38 citations


Journal ArticleDOI
TL;DR: It is found that subtype C spread at least three-fold faster than other subtypes circulating in Central and East Africa following a 15-year period of local transmission in southern DRC, and it is suggested that socio-historical rather than evolutionary factors may have determined the epidemiological fate of sub type C in sub-Saharan Africa.
Abstract: Since the ignition of the HIV-1 group M pandemic in the beginning of the 20th century, group M lineages have spread heterogeneously throughout the world. Subtype C spread rapidly through sub-Saharan Africa and is currently the dominant HIV lineage worldwide. Yet the epidemiological and evolutionary circumstances that contributed to its epidemiological expansion remain poorly understood. Here, we analyse 346 novel pol sequences from the DRC to compare the evolutionary dynamics of the main HIV-1 lineages, subtypes A1, C and D. Our results place the origins of subtype C in the 1950s in Mbuji-Mayi, the mining city of southern DRC, while subtypes A1 and D emerged in the capital city of Kinshasa, and subtypes H and J in the less accessible port city of Matadi. Following a 15-year period of local transmission in southern DRC, we find that subtype C spread at least three-fold faster than other subtypes circulating in Central and East Africa. In conclusion, our results shed light on the origins of HIV-1 main lineages and suggest that socio-historical rather than evolutionary factors may have determined the epidemiological fate of subtype C in sub-Saharan Africa.

31 citations


Journal ArticleDOI
TL;DR: The frequency and potential long-term presence of viral RNA in semen confirmed that systematic prevention measures in male survivors are required and suggested that knowledge on viral reservoir in immune-privileged sites and its impact are still incomplete.
Abstract: Background With the increasing frequency and impact of Ebola virus disease (EVD) outbreaks illustrated by recent epidemics, a good understanding of the extent of viral persistance or ribonucleic acid (RNA) detection in body fluids from survivors is urgently needed. Methods Ebola viral RNA shedding was studied with molecular assays in semen (n = 1368), urine (n = 1875), cervicovaginal fluid (n = 549), saliva (n = 900), breast milk (n = 168), and feces (n = 558) from EVD survivors in Guinea (PostEbogui cohort, n = 802) at a regular base period until 40 months after inclusion. Results Twenty-seven of 277 (9.8%) male survivors tested positive for Ebola RNA in at least 1 semen sample. The probability of remaining positive for Ebola RNA in semen was estimated at 93.02% and 60.12% after 3 and 6 months. Viral RNA in semen was more frequent in patients with eye pain (P = .036), joint pain (P = .047), and higher antibody levels to Ebola virus antigens (nucleoprotein [P = .001], glycoprotein [P = .05], and viral protein-40 [P = .05]). Ebola RNA was only rarely detected in the following body fluids from EVD survivors: saliva (1 of 454), urine (2 of 593), breast milk (2 of 168), cervicovaginal secretions (0 of 273), and feces (0 of 330). Ribonucleic acid was detected in breast milk 1 month after delivery but 500 days after discharge of Ebola treatment unit (ETU) in 1 woman who became pregnant 7 months after discharge from the ETU. Conclusions The frequency and potential long-term presence of viral RNA in semen confirmed that systematic prevention measures in male survivors are required. Our observation in breast milk suggests that our knowledge on viral reservoir in immune-privileged sites and its impact are still incomplete.

27 citations


Journal ArticleDOI
TL;DR: Retrospectively, the feasibility of using genomics to rapidly characterise a new Ebola virus variant within the timeframe of an outbreak is shown andylogenetic analysis provides further indications that these variants are evolving at differing rates.
Abstract: Summary Background The 2018 Ebola virus disease (EVD) outbreak in Equateur Province, Democratic Republic of the Congo, began on May 8, and was declared over on July 24; it resulted in 54 documented cases and 33 deaths. We did a retrospective genomic characterisation of the outbreak and assessed potential therapeutic agents and vaccine (medical countermeasures). Methods We used target-enrichment sequencing to produce Ebola virus genomes from samples obtained in the 2018 Equateur Province outbreak. Combining these genomes with genomes associated with known outbreaks from GenBank, we constructed a maximum-likelihood phylogenetic tree. In-silico analyses were used to assess potential mismatches between the outbreak strain and the probes and primers of diagnostic assays and the antigenic sites of the experimental rVSVΔG-ZEBOV-GP vaccine and therapeutics. An in-vitro flow cytometry assay was used to assess the binding capability of the individual components of the monoclonal antibody cocktail ZMapp. Findings A targeted sequencing approach produced 16 near-complete genomes. Phylogenetic analysis of these genomes and 1011 genomes from GenBank revealed a distinct cluster, confirming a new Ebola virus variant, for which we propose the name “Tumba”. This new variant appears to have evolved at a slower rate than other Ebola virus variants (0·69 × 10−3 substitutions per site per year with “Tumba” vs 1·06 × 10−3 substitutions per site per year without “Tumba”). We found few sequence mismatches in the assessed assay target regions and antigenic sites. We identified nine amino acid changes in the Ebola virus surface glycoprotein, of which one resulted in reduced binding of the 13C6 antibody within the ZMapp cocktail. Interpretation Retrospectively, we show the feasibility of using genomics to rapidly characterise a new Ebola virus variant within the timeframe of an outbreak. Phylogenetic analysis provides further indications that these variants are evolving at differing rates. Rapid in-silico analyses can direct in-vitro experiments to quickly assess medical countermeasures. Funding Defense Biological Product Assurance Office .

24 citations


Journal ArticleDOI
TL;DR: A high level of virological failure and a high percentage of viral resistance among children receiving health care in decentralized facilities in Senegal is observed.
Abstract: In Senegal in 2015, an estimated 4800 children were living with HIV, with 1200 receiving ARV treatment, of whom half had follow-up care in decentralized sites outside Dakar. However, until now no studies have determined the efficacy of pediatric treatment in decentralized settings, even though the emergence of viral resistance, particularly among children in Africa, is a well-known phenomenon. This study aimed to assess the virological status of HIV-infected children in all decentralized facilities to help improve access to quality care. A cross-sectional epidemiological and virological study was conducted in all of Senegal’s regions, except Dakar, between March and June 2015 and sought to include all HIV-infected children and adolescents (0–19 years), treated or not with ARVs. Socio-demographic and clinical data and a blood sample on blotting paper were collected for children from treatment sites. Samples were routed on public transportation, assisted by a network of community health workers. A viral load (VL) assay was performed for each child, followed by genotyping when it exceeded 1000 copies/mL (3 log10). Of the 851 identified children, 666 (78%) were enrolled in the study. Half of the children were girls, and the average age was 8 years (6 months–19 years). Most of the children (96.7%) were infected with HIV-1, and 90% were treated with ART, primarily with AZT + 3TC + NVP/EFV therapeutic regimen. The median duration of time on ART was 21 months (1–129). VL was measured for 2% of children before this study. Almost two-thirds (64%) of the children are experiencing virological failure. Among them, there was resistance to at least one drug for 86.5% of cases. Also, 25% children presented resistance to one drug and 40% to two out of three. For nearly one-third of the children presenting resistance, none of the three drugs of the treatment was active. Factors associated with virological failure were male sex, follow-up by a generalist rather than a specialist, and treatment interruptions. We observed a high level of virological failure and a high percentage of viral resistance among children receiving health care in decentralized facilities in Senegal.

18 citations


DOI
01 Nov 2019
TL;DR: Ebola outbreaks in West Africa in 2014 and those in the DRC that began in 2018 were an opportunity to develop and deploy new diagnostic techniques in laboratories in Guinea and the Democratic Republic of the Congo, making it possible to identify the infectious agent rapidly, to trace contamination chains in real time, and to develop a reliable serological tool for differential diagnoses.
Abstract: Emerging infectious diseases appear recurrently and represent a threat to global health security. Africa is particularly exposed to the risks of infectious epidemics, due to both the number of circulating infectious agents, especially in wildlife, and the social and environmental factors that promote their epidemic spread. Ebola outbreaks in West Africa in 2014 and those in the DRC that began in 2018 were an opportunity to develop and deploy new diagnostic techniques in laboratories in Guinea and the Democratic Republic of the Congo (DRC). These tools made it possible to identify the infectious agent rapidly, to trace contamination chains in real time to enable effective interventions, and to develop a reliable serological tool for differential diagnoses. Today, equipped and functional facilities exist in both countries, led by Guinean and Congolese researchers trained to high levels of competence and benefiting from unique experience and field knowledge.

1 citations