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During the 10th outbreak of Ebola virus disease in the Democratic Republic of the Congo, the Institut National de Recherche Biomédicale strategically positioned 13 decentralized field laboratories with dedicated equipment to quickly detect cases as the outbreak evolved. The laboratories were operated by national staff, who quickly handed over competencies and skills to local persons to successfully manage future outbreaks. Laboratories analyzed ≈230,000 Ebola diagnostic samples under stringent biosafety measures, documentation, and database management. Field laboratories diversified their activities (diagnosis, chemistry and hematology, survivor follow-up, and genomic sequencing) and shipped 127,993 samples from the field to a biorepository in Kinshasa under good conditions. Deploying decentralized and well-equipped laboratories run by local personnel in at-risk countries for Ebola virus disease outbreaks is an efficient response; all activities are quickly conducted in the field.

Summary: Background: Ebola virus disease (EVD) outbreaks have emerged in Central and West Africa. EVD diagnosis relies principally on RT-PCR testing with GeneXpert®, which has logistical and cost restrictions at the peripheral level of the health system. Rapid diagnostic tests (RDTs) would offer a valuable alternative at the point-of-care to reduce the turn-around time, if they show good performance characteristics. We evaluated the performance of four EVD RDTs against the reference standard GeneXpert® on stored EVD positive and negative blood samples collected between 2018 and 2021 from outbreaks in eastern Democratic Republic of the Congo (DRC). Methods: We conducted a prospective and observational study in the laboratory on QuickNavi-Ebola™, OraQuick® Ebola Rapid Antigen, Coris® EBOLA Ag K-SeT, and Standard® Q Ebola Zaïre Ag RDTs using left-over archived frozen EDTA whole blood samples. We randomly selected 450 positive and 450 negative samples from the EVD biorepositories in DRC, across a range of GeneXpert® cycle threshold values (Ct-values). RDT results were read by three persons and we considered an RDT result as “positive”, when it was flagged as positive by at least two out of the three readers. We estimated the sensitivity and specificity through two independent generalized (logistic) linear mixed models (GLMM). Findings: 476 (53%) of 900 samples had a positive GeneXpert Ebola result when retested. The QuickNavi-Ebola™ showed a sensitivity of 56.8% (95% CI 53.6–60.0) and a specificity of 97.5% (95% CI 96.2–98.4), the OraQuick® Ebola Rapid Antigen test displayed 61.6% (95% CI 57.0–65.9) sensitivity and 98.1% (95% CI 96.2–99.1) specificity, the Coris® EBOLA Ag K-SeT showed 25.0% (95% CI 22.3–27.9) sensitivity and 95.9% (95% CI 94.2–97.1) specificity, and the Standard® Q Ebola Zaïre Ag displayed 21.6% (95% CI 18.1–25.7) sensitivity and 99.1% (95% CI 97.4–99.7) specificity. Interpretation: None of the RDTs evaluated approached the ''desired or acceptable levels'' for sensitivity set out in the WHO target product profile, while all of the tests met the ''desired level'' for specificity. Nevertheless, the QuickNavi-Ebola™ and OraQuick® Ebola Rapid Antigen Test demonstrated the most favorable profiles, and may be used as frontline tests for triage of suspected-cases while waiting for RT-qPCR confirmatory testing. Funding: Institute of Tropical Medicine Antwerp/EDCTP PEAU-EBOV-RDC project.

ABSTRACT: Objectives: To describe the characteristics of nosocomial cases of Ebola virus disease (EVD) in the Democratic Republic of the Congo between July 2018 and May 2020 in order to inform future interventions. Methods: Nosocomial cases of EVD were identified during outbreak response surveillance, and a retrospective analysis of cases was conducted according to demographic characteristics and type of health facility (HF). Results: Of 3481 cases of EVD, 579 (16.6%) were nosocomial. Of these, 332 cases occurred in women (57.3%). Patients and visitors accounted for 419 cases (72.4%), of which 79 (18.9%) were aged 6–≤18 years and 108 (25.8%) were aged ≤5 years. Health workers (HWs) accounted for the remaining 160 (27.6%) nosocomial cases. The case fatality rate (CFR) for HWs (66/160, 41.3%) was significantly lower than the CFR for patients and visitors (292/419, 69.7%) (P39 beds) had the highest prevalence of nosocomial EVD (148/579, 25.6%). Among HFs with at least one case of nosocomial infection, 50.0% (98/196) were privately owned. Conclusions: Nurses and traditional healers should be targeted for infection prevention and control training, and supportive supervision should be provided to HFs to mitigate EVD transmission.

After a pilot study, we tested 443 cadavers using OraQuick Ebola rapid diagnostic tests during surveillance after the 10th Ebola outbreak in the Democratic Republic of the Congo. No false negative and 2% false-positive results were reported. Quickly returning results and engaging the community enabled timely public health actions.

Summary: Background: A paucity of data is available on virologic and biochemical characteristics of paediatric Ebolavirus disease (EVD), compared to adults. Methods: We conducted a retrospective chart review of children (7.6 log10copies/mL, alanine transaminase >525 U/L, C-reactive protein >100 mg/L, blood urea nitrogen >7.5 mmol/L, rhabdomyolysis, and.acute kidney injury. Interpretation: Paediatric EVD patients, like adults, experience multiorgan dysfunction with life-threatening electrolyte imbalances, hypoglycaemia, kidney injury, liver injury, and rhabdomyolysis. Paediatric patients have significantly higher VLs throughout the course of EVD than adults. Funding: This study was not funded.

Abstract Background Design thinking allows challenging problems to be redefined in order to identify alternative user-center strategies and solutions. To address the many challenges associated with collecting and reporting data during the 2014 Ebola outbreak in Guinea, Liberia and Sierra Leone, we used a design thinking approach to build the Global Ebola Laboratory Data collection and reporting system. Main text We used the five-stage Design Thinking model proposed by Hasso-Plattner Institute of Design at Stanford in Guinea, Liberia and Sierra Leone. This approach offers a flexible model which focuses on empathizing, defining, ideating, prototyping, and testing. A strong focus of the methodology includes end-users’ feedback from the beginning to the end of the process. This is an iterative methodology that continues to adapt according to the needs of the system. The stages do not need to be sequential and can be run in parallel, out of order, and repeated as necessary. Design thinking was used to develop a data collection and reporting system, which contains all laboratory data from the three countries during one of the most complicated multi-country outbreaks to date. The data collection and reporting system was used to orient the response interventions at the district, national, and international levels within the three countries including generating situation reports, monitoring the epidemiological and operational situations, providing forecasts of the epidemic, and supporting Ebola-related research and the Ebola National Survivors programs within each country. Conclusions Our study demonstrates the numerous benefits that arise when using a design thinking methodology during an outbreak to solve acute challenges within the national health information system and the authors recommend it’s use during future complex outbreaks.

At the end of the 2013–2016 Ebola virus disease outbreak in Guinea, we implemented an alert system for early detection of Ebola resurgence among survivors. Survivors were asked to report health alerts in their household and provide body fluid specimens for laboratory testing. During April–September 2016, a total of 1,075 (88%) of 1,215 survivors participated in the system; follow up occurred at a median of 16 months after discharge (interquartile range 14–18 months). Of these, 784 acted as focal points and reported 1,136 alerts (including 4 deaths among survivors). A total of 372 (91%) of 408 eligible survivors had >1 semen specimen tested; of 817 semen specimens, 5 samples from 4 survivors were positive up to 512 days after discharge. No lochia (0/7) or breast milk (0/69) specimens tested positive. Our findings underscore the importance of long-term monitoring of survivors’ semen samples in an Ebola-affected country.

The 2013–2016 Ebola virus (EBOV) outbreak in West Africa was the largest and most complex outbreak ever, with a total number of cases and deaths higher than in all previous EBOV outbreaks combined. The outbreak was characterized by rapid spread of the infection in nations that were weakly prepared to handle it. EBOV ribonucleic acid (RNA) is known to persist in body fluids following disease recovery, and studying this persistence is crucial for controlling such epidemics. Observational cohort studies investigating EBOV persistence in semen require following up recently recovered survivors of Ebola virus disease (EVD), from recruitment to the time when their semen tests negative for EBOV, the endpoint being time-to-event. Because recruitment of EVD survivors takes place weeks or months following disease recovery, the event of interest may have already occurred. Survival analysis methods are the best suited for the estimation of the virus persistence in body fluids but must account for left- and interval-censoring present in the data, which is a more complex problem than that of presence of right censoring alone. Using the Sierra Leone Ebola Virus Persistence Study, we discuss study design issues, endpoint of interest and statistical methodologies for interval- and right-censored non-parametric and parametric survival modelling. Using the data from 203 EVD recruited survivors, we illustrate the performance of five different survival models for estimation of persistence of EBOV in semen. The interval censored survival analytic methods produced more precise estimates of EBOV persistence in semen and were more representative of the source population than the right censored ones. The potential to apply these methods is enhanced by increased availability of statistical software to handle interval censored survival data. These methods may be applicable to diseases of a similar nature where persistence estimation of pathogens is of interest.

BackgroundOnly one recommendation currently exists for the treatment of Lassa fever (LF), which is ribavirin administered in conjunction with supportive care. This recommendation is primarily based on evidence generated from a single clinical trial that was conducted more than 30 years ago-the methodology and results of which have recently come under scrutiny. The requirement for novel therapeutics and reassessment of ribavirin is therefore urgent. However, a significant amount of work now needs to be undertaken to ensure that future trials for LF can be conducted consistently and reliably to facilitate the efficient generation of evidence.MethodologyWe convened a consultation group to establish the position of clinicians and researchers on the core components of future trials. A Core Eligibility Criteria (CEC), Core Case Definition (CCD), Core Outcome Set (COS) and Core Data Variables (CDV) were developed through the process of a multi-stakeholder consultation that took place using a modified-Delphi methodology.ResultsA consensus position was achieved for each aspect of the framework, which accounts for the inclusion of pregnant women and children in future LF clinical trials. The framework consists of 8 core criteria, as well as additional considerations for trial protocols.ConclusionsThis project represents the first step towards delineating the clinical development pathway for new Lassa fever therapeutics, following a period of 40 years without advancement. Future planned projects will bolster the work initiated here to continue the advancement of LF clinical research through a regionally-centred, collaborative methodology, with the aim of delineating a clear pathway through which LF clinical trials can progress efficiently and ensure sustainable investments are made in research capacity at a regional level.

Process mapping is a systems thinking approach used to understand, analyse and optimise processes within complex systems. We aim to demonstrate how this methodology can be applied during disease outbreaks to strengthen response and health systems. Process mapping exercises were conducted during three unique emerging disease outbreak contexts with different: mode of transmission, size, and health system infrastructure. System functioning improved considerably in each country. In Sierra Leone, laboratory testing was accelerated from 6 days to within 24 hours. In the Democratic Republic of Congo, time to suspected case notification reduced from 7 to 3 days. In Nigeria, key data reached the national level in 48 hours instead of 5 days. Our research shows that despite the chaos and complexities associated with emerging pathogen outbreaks, the implementation of a process mapping exercise can address immediate response priorities while simultaneously strengthening components of a health system.

Summary: Following cessation of continuous Ebola virus (EBOV) transmission within Western Africa, sporadic EBOV disease (EVD) cases continued to re-emerge beyond the viral incubation period. Epidemiological and genomic evidence strongly suggests that this represented transmission from EVD survivors. To investigate whether persistent infections are characterized by ongoing viral replication, we sequenced EBOV from the semen of nine EVD survivors and a subset of corresponding acute specimens. EBOV evolutionary rates during persistence were either similar to or reduced relative to acute infection rates. Active EBOV replication/transcription continued during convalescence, but decreased over time, consistent with viral persistence rather than viral latency. Patterns of genetic divergence suggest a moderate relaxation of selective constraints within the sGP carboxy-terminal tail during persistent infections, but do not support widespread diversifying selection. Altogether, our data illustrate that EBOV persistence in semen, urine, and aqueous humor is not a quiescent or latent infection. : Whitmer et al. find that Ebola virus continues replication/transcription within the eye and male genital tract of Ebola virus disease survivors. They describe viral replication, evolutionary rates, and selective pressures experienced during acute and persistent infection. Keywords: Ebola virus, EVD survivors, persistent viral infection, evolutionary pressure, evolutionary rates, RNA hyper-editing

Crimean-Congo haemorrhagic fever (CCHF) is the most widespread, tick-borne viral disease affecting humans. The disease is endemic in many regions, such as Africa, Asia, Eastern and Southern Europe, and Central Asia. Recently, the incidence of CCHF has increased rapidly in the countries of the World Health Organization Eastern Mediterranean Region (WHO EMR), with sporadic human cases and outbreaks of CCHF being reported from a number of countries in the region. Despite the rapidly growing incidence of the disease, there are currently no accurate data on the burden of the disease in the region due to the different surveillance systems used for CCHF in these countries. In an effort to increase our understanding of the epidemiology and risk factors for the transmission of the CCHF virus (CCHFV; a Nairovirus of the family Bunyaviridae) in the WHO EMR, and to identify the current knowledge gaps that are hindering effective control interventions, a sub-regional meeting was organized in Muscat, Oman, from December 7 to 9, 2015. This article summarizes the current knowledge of the disease in the region, identifies the knowledge gaps that present challenges for the prevention and control of CCHFV, and details a strategic framework for research and development activities that would be necessary to curb the ongoing and new threats posed by CCHFV.

In October 2015, a new case of Ebola virus disease in Guinea was detected. Case investigation, serology, and whole-genome sequencing indicated possible transmission of the virus from an Ebola virus disease survivor to another person and then to the case-patient reported here. This transmission chain over 11 months suggests slow Ebola virus evolution.

BACKGROUND:The 2013-2016 West African Ebola virus disease epidemic was unprecedented in terms of the number of cases and survivors. Prior to this epidemic there was limited data available on the persistence of Ebola virus in survivors' body fluids and the potential risk of transmission, including sexual transmission. METHODOLOGY/PRINCIPAL FINDINGS:Given the urgent need to determine the persistence of Ebola virus in survivors' body fluids, an observational cohort study was designed and implemented during the epidemic response operation in Sierra Leone. This publication describes study implementation methodology and the key lessons learned. Challenges encountered during implementation included unforeseen duration of follow-up, complexity of interpreting and communicating laboratory results to survivors, and the urgency of translating research findings into public health practice. Strong community engagement helped rapidly implement the study during the epidemic. The study was conducted in two phases. The first phase was initiated within five months of initial protocol discussions and assessed persistence of Ebola virus in semen of 100 adult men. The second phase assessed the persistence of virus in multiple body fluids (semen or vaginal fluid, menstrual blood, breast milk, and urine, rectal fluid, sweat, saliva, tears), of 120 men and 120 women. CONCLUSION/SIGNIFICANCE:Data from this study informed national and global guidelines in real time and demonstrated the need to implement semen testing programs among Ebola virus disease survivors. The lessons learned and study tools developed accelerated the implementation of such programs in Ebola virus disease affected countries, and also informed studies examining persistence of Zika virus. Research is a vital component of the public health response to an epidemic of a poorly characterized disease. Adequate resources should be rapidly made available to answer critical research questions, in order to better inform response efforts.

During the recent Ebola outbreak in West Africa several international mobile laboratories were deployed to the mainly affected countries Guinea, Sierra Leone and Liberia to provide ebolavirus diagnostic capacity. Additionally, imported cases and small outbreaks in other countries required global preparedness for Ebola diagnostics. Detection of viral RNA by reverse transcription polymerase chain reaction has proven effective for diagnosis of ebolavirus disease and several assays are available. However, reliability of these assays is largely unknown and requires serious evaluation. Therefore, a proficiency test panel of 11 samples was generated and distributed on a global scale. Panels were analyzed by 83 expert laboratories and 106 data sets were returned. From these 78 results were rated optimal and 3 acceptable, 25 indicated need for improvement. While performance of the laboratories deployed to West Africa was superior to the overall performance there was no significant difference between the different assays applied.

Summary: Background: By January, 2016, all known transmission chains of the Ebola virus disease (EVD) outbreak in west Africa had been stopped. However, there is concern about persistence of Ebola virus in the reproductive tract of men who have survived EVD. We aimed to use biostatistical modelling to describe the dynamics of Ebola virus RNA load in seminal fluid, including clearance parameters. Methods: In this longitudinal study, we recruited men who had been discharged from three Ebola treatment units in Guinea between January and July, 2015. Participants provided samples of seminal fluid at follow-up every 3–6 weeks, which we tested for Ebola virus RNA using quantitative real-time RT-PCR. Representative specimens from eight participants were then inoculated into immunodeficient mice to test for infectivity. We used a linear mixed-effect model to analyse the dynamics of virus persistence in seminal fluid over time. Findings: We enrolled 26 participants and tested 130 seminal fluid specimens; median follow up was 197 days (IQR 187–209 days) after enrolment, which corresponded to 255 days (228–287) after disease onset. Ebola virus RNA was detected in 86 semen specimens from 19 (73%) participants. Median duration of Ebola virus RNA detection was 158 days after onset (73–181; maximum 407 days at end of follow-up). Mathematical modelling of the quantitative time-series data showed a mean clearance rate of Ebola virus RNA from seminal fluid of −0·58 log units per month, although the clearance kinetic varied greatly between participants. Using our biostatistical model, we predict that 50% and 90% of male survivors clear Ebola virus RNA from seminal fluid at 115 days (90% prediction interval 72–160) and 294 days (212–399) after disease onset, respectively. We also predicted that the number of men positive for Ebola virus RNA in affected countries would decrease from about 50 in January 2016, to fewer than 1 person by July, 2016. Infectious virus was detected in 15 of 26 (58%) specimens tested in mice. Interpretation: Time to clearance of Ebola virus RNA from seminal fluid varies greatly between individuals and could be more than 13 months. Our predictions will assist in decision-making about surveillance and preventive measures in EVD outbreaks. Funding: This study was funded by European Union's Horizon 2020 research and innovation programme, Directorate-General for International Cooperation and Development of the European Commission, Institut national de la santé et de la recherche médicale (INSERM), German Research Foundation (DFG), and Innovative Medicines Initiative 2 Joint Undertaking.

In 2014, Ebola virus (EBOV) was identified as the etiological agent of a large and still expanding outbreak of Ebola virus disease (EVD) in West Africa and a much more confined EVD outbreak in Middle Africa. Epidemiological and evolutionary analyses confirmed that all cases of both outbreaks are connected to a single introduction each of EBOV into human populations and that both outbreaks are not directly connected. Coding-complete genomic sequence analyses of isolates revealed that the two outbreaks were caused by two novel EBOV variants, and initial clinical observations suggest that neither of them should be considered strains. Here we present consensus decisions on naming for both variants (West Africa: “Makona”, Middle Africa: “Lomela”) and provide database-compatible full, shortened, and abbreviated names that are in line with recently established filovirus sub-species nomenclatures.

Sequence determination of complete or coding-complete genomes of viruses is becoming common practice for supporting the work of epidemiologists, ecologists, virologists, and taxonomists. Sequencing duration and costs are rapidly decreasing, sequencing hardware is under modification for use by non-experts, and software is constantly being improved to simplify sequence data management and analysis. Thus, analysis of virus disease outbreaks on the molecular level is now feasible, including characterization of the evolution of individual virus populations in single patients over time. The increasing accumulation of sequencing data creates a management problem for the curators of commonly used sequence databases and an entry retrieval problem for end users. Therefore, utilizing the data to their fullest potential will require setting nomenclature and annotation standards for virus isolates and associated genomic sequences. The National Center for Biotechnology Information’s (NCBI’s) RefSeq is a non-redundant, curated database for reference (or type) nucleotide sequence records that supplies source data to numerous other databases. Building on recently proposed templates for filovirus variant naming [ ()////-], we report consensus decisions from a majority of past and currently active filovirus experts on the eight filovirus type variants and isolates to be represented in RefSeq, their final designations, and their associated sequences.

Pneumonic plague is a highly transmissible infectious disease for which fatality rates can be high if untreated; it is considered extremely lethal. Without prompt diagnosis and treatment, disease management can be problematic. In the Democratic Republic of the Congo, 2 outbreaks of pneumonic plague occurred during 2005 and 2006. In 2005, because of limitations in laboratory capabilities, etiology was confirmed only through retrospective serologic studies. This prompted modifications in diagnostic strategies, resulting in isolation of Yersinia pestis during the second outbreak. Results from these outbreaks demonstrate the utility of a rapid diagnostic test detecting F1 antigen for initial diagnosis and public health management, as well as the need for specialized sampling kits and trained personnel for quality specimen collection and appropriate specimen handling and preservation for plague confirmation and Y. pestis isolation. Efficient frontline management and a streamlined diagnostic strategy are essential for confirming plague, especially in remote areas.

To determine the outbreak source of monkeypox virus (MPXV) infections in Unity State, Sudan, in November 2005, we conducted a retrospective investigation. MPXV was identified in a sub-Sahelian savannah environment. Three case notification categories were used: suspected, probable, and confirmed. Molecular, virologic, and serologic assays were used to test blood specimens, vesicular swabs, and crust specimens obtained from symptomatic and recovering persons. Ten laboratory-confirmed cases and 9 probable cases of MPXV were reported during September–December 2005; no deaths occurred. Human-to-human transmission up to 5 generations was described. Our investigation could not fully determine the source of the outbreak. Preliminary data indicate that the MPXV strain isolated during this outbreak was a novel virus belonging to the Congo Basin clade. Our results indicate that MPXV should be considered endemic to the wetland areas of Unity State. This finding will enhance understanding of the ecologic niche for this virus.

To determine reservoir hosts for Marburg virus (MARV), we examined the fauna of a mine in northeastern Democratic Republic of the Congo. The mine was associated with a protracted outbreak of Marburg hemorrhagic fever during 1998–2000. We found MARV nucleic acid in 12 bats, comprising 3.0%–3.6% of 2 species of insectivorous bat and 1 species of fruit bat. We found antibody to the virus in the serum of 9.7% of 1 of the insectivorous species and in 20.5% of the fruit bat species, but attempts to isolate virus were unsuccessful.

Detection and control of emerging infectious diseases in conflict situations are major challenges due to multiple risk factors known to enhance emergence and transmission of infectious diseases. These include inadequate surveillance and response systems, destroyed infrastructure, collapsed health systems and disruption of disease control programs, and infection control practices even more inadequate than those in resource-poor settings, as well as ongoing insecurity and poor coordination among humanitarian agencies. This article outlines factors that potentiate emergence and transmission of infectious diseases in conflict situations and highlights several priority actions for their containment and control.

ABSTRACT Available evidence demonstrates that direct patient contact and contact with infectious body fluids are the primary modes for Ebola virus transmission, but this is based on a limited number of studies. Key areas requiring further study include (i) the role of aerosol transmission (either via large droplets or small particles in the vicinity of source patients), (ii) the role of environmental contamination and fomite transmission, (iii) the degree to which minimally or mildly ill persons transmit infection, (iv) how long clinically relevant infectiousness persists, (v) the role that “superspreading events” may play in driving transmission dynamics, (vi) whether strain differences or repeated serial passage in outbreak settings can impact virus transmission, and (vii) what role sylvatic or domestic animals could play in outbreak propagation, particularly during major epidemics such as the 2013–2015 West Africa situation. In this review, we address what we know and what we do not know about Ebola virus transmission. We also hypothesize that Ebola viruses have the potential to be respiratory pathogens with primary respiratory spread.

The mononegaviral family Filoviridae has eight members assigned to three genera and seven species. Until now, genus and species demarcation were based on arbitrarily chosen filovirus genome sequence divergence values (≈50% for genera, ≈30% for species) and arbitrarily chosen phenotypic virus or virion characteristics. Here we report filovirus genome sequence-based taxon demarcation criteria using the publicly accessible PAirwise Sequencing Comparison (PASC) tool of the US National Center for Biotechnology Information (Bethesda, MD, USA). Comparison of all available filovirus genomes in GenBank using PASC revealed optimal genus demarcation at the 55–58% sequence diversity threshold range for genera and at the 23–36% sequence diversity threshold range for species. Because these thresholds do not change the current official filovirus classification, these values are now implemented as filovirus taxon demarcation criteria that may solely be used for filovirus classification in case additional data are absent. A near-complete, coding-complete, or complete filovirus genome sequence will now be required to allow official classification of any novel “filovirus.” Classification of filoviruses into existing taxa or determining the need for novel taxa is now straightforward and could even become automated using a presented algorithm/flowchart rooted in RefSeq (type) sequences.

Monkeypox is a major public health concern in the Congo Basin area, with changing patterns of human case occurrences reported in recent years. Whether this trend results from better surveillance and detection methods, reduced proportions of vaccinated vs. non-vaccinated human populations, or changing environmental conditions remains unclear. Our objective is to examine potential correlations between environment and transmission of monkeypox events in the Congo Basin. We created ecological niche models based on human cases reported in the Congo Basin by the World Health Organization at the end of the smallpox eradication campaign, in relation to remotely-sensed Normalized Difference Vegetation Index datasets from the same time period. These models predicted independent spatial subsets of monkeypox occurrences with high confidence; models were then projected onto parallel environmental datasets for the 2000s to create present-day monkeypox suitability maps. Recent trends in human monkeypox infection are associated with broad environmental changes across the Congo Basin. Our results demonstrate that ecological niche models provide useful tools for identification of areas suitable for transmission, even for poorly-known diseases like monkeypox.

BACKGROUND: Marburg virus (MARV), a zoonotic pathogen causing severe hemorrhagic fever in man, has emerged in Angola resulting in the largest outbreak of Marburg hemorrhagic fever (MHF) with the highest case fatality rate to date. METHODOLOGY/PRINCIPAL FINDINGS: A mobile laboratory unit (MLU) was deployed as part of the World Health Organization outbreak response. Utilizing quantitative real-time PCR assays, this laboratory provided specific MARV diagnostics in Uige, the epicentre of the outbreak. The MLU operated over a period of 88 days and tested 620 specimens from 388 individuals. Specimens included mainly oral swabs and EDTA blood. Following establishing on site, the MLU operation allowed a diagnostic response in

Si de nombreuses études portent sur la trypanosomoses chez les animaux domestiques, peu de rcherches ont été effectuées sur la faune sauvage d'Afrique occidentale. Les résultats préliminaires sur la comparaison de trois méthodes de dépistages des trypanosomes : le frottis de sang, la détection des antigènes circulants par le technique ELISA et l'isolement in vitro des trypanosomes par le "kit for in vitro isolation" (KIVI), chez les animaux sauvages du parc national de la Comoé en Côte d'ivoire, ont permis de confirmer l'existence de cette infection chez ces animaux sans toutefois identifier de façon précise les espèces de trypanosomes en cause. Des investigations ultérieures permettront d'affiner l'identification des souches de parasites isolées par KIVI.

Le “syndrome nerveux des ovins” en Côte-d’Ivoire est assimilable à la “nécrose du cortex cérébral” (NCC) due à une carence en vitamine B1. Tous les symptômes classiques de la NCC ont été observés (ataxie locomotrice suivie de paralysies) et les lésions histologiques de polioencéphalomalacie ont été mises en évidence. En revanche, les circonstances d’apparition de la maladie sont très différentes dans les deux cas : si la NCC est une maladie des jeunes ruminants à l’engrais dans les pays développés, le syndrome nerveux des ovins se manifeste essentiellement, en Côte-d’lvoire, durant la saison sèche, lorsque le pâturage devient sec et rare et que la complémentation alimentaire est insuffisante. La cause principale, relativement univoque, est donc représentée par une dégradation brutale de la valeur nutritionnelle de la ration alimentaire, mais l’étiopathogénie précise de la maladie reste inconnue. Dans un troupeau atteint, 10 à 30 % des animaux peuvent être malades et 80 à 90 % d’entre eux vont mourir. Sur le plan du diagnostic, aucune épreuve biochimique classique n’est suffisamment spécifique pour être retenue pour une confirmation formelle du syndrome nerveux. Il faut cependant signaler que les CK (créatinine kinase) sont très régulièrement augmentées et que les ASAT (aspartate aminotransférase) sont élevées dans 75 % des cas. Le diagnostic formel reste donc basé, dans les conditions actuelles pratiques de terrain en Afrique, sur l’efficacité du traitement avec la vitamine B1 et, pour l’animal mort, sur l’analyse histologique du cerveau.

Le syndrome nerveux des ovins en Côte d'Ivoire a été présenté pour ses aspects cliniques et épidémiologiques, dans un premier article et il a été assimilé à la nécrose du cortex cérébral liée à une carence en vitamine B1. Les pertes économiques dues à cette maladie s'élèvent de 1500 à 2000 F CFA (30 à 40 FF) par animal entretenu et par an, ce qui justifiait que l'on se penche sur le problème de la prophylaxie. Un programme d'injection hebdomadaire de 100 mg de chlorhydrate de thiamine, pendant toute la durée de la saison sèche, s'est révélé très efficace. De plus, ce programme s'avère rentable pour l'éleveur, si le coût de l'acte (injection) proprement dit n'est pas compté. Si on inclut uniquement le prix du produit, le calcul montre un taux de rémunération des investissements (rapport des bénéfices sur les coûts du programme) de 4,8 (coût de la thiamine à 400 F CFA) à 30,6 (Coût de la thiamine à 66 F CFA). Les autres critères de rentabilité (valeur actualisée nette différentielle et gains induits) etudiés démontrent le même effet positif du schéma de prophylaxie testé.

De 1988 à 1990, une enquête sérologique portant sur un échantillon de 1051 sérums ovins a été menée dans le Sud forestier de la Côte-d'Ivoire afin d'y étudier l'incidence de la fièvre de la vallée du Rift (FVR) et le rôle de ce virus dans la pathologie de la reproduction. La prévalence de la FVR est de 6,85 %. Aucune différence n'a été observée entre les trois régions géographiques déterminées, ni entre les trois années de l'étude. La prévalence augmente avec l'âge de façon significative. La maladie doit être considérée comme enzootique en Côte-d'Ivoire. On trouve une corrélation positive entre séropositivité et avortements, ce qui doit inciter à mieux évaluer l'impact économique de la FVR en santé animale. La présence d 'anticorps chez les animaux âgés de 6 mois à un an, signant une circulation active du virus, implique une surveillance impérative plus large de la situation en Côte-d'Ivoire en raison du risque pour la population humaine en contact avec les animaux.

Au cours de la saison sèche 1990-1991, une épidémie de kératoconjonctivite granuleuse ovine a sévi en Côte-d'Ivoire. L'étiologie chlamydienne de l'affection a été démontrée. Tous les troupeaux ont été atteints avec une morbidité variant de 30 à 70 p. 100. Les lésions de kératite ont été observées sur 5 à 15 p. 100 des malades. Le traitement à l'Auréomycine (ND-Specia, pommade ophtalmique) s'est avéré constamment efficace.

Une vague épizootique de fièvre aphteuse due au type SAT2 a sévi dans les élevages bovins, ovins et porcins en Côte-d'Ivoire. La morbidité peu élevée et la très faible mortalité observées ont amené à préconiser une vaccination uniquement dans les élevages de type intensif et de haute valeur zootechnique.

By analyzing vesicle fluids and crusted scabs from 136 persons with suspected monkeypox, we identified 51 cases of monkeypox by PCR, sequenced the hemagglutinin gene, and confirmed 94% of cases by virus culture. PCR demonstrated chickenpox in 61 patients. Coinfection with both viruses was found in 1 additional patient.

To facilitate rapid, unbiased, differential diagnosis of infectious diseases, we designed GreeneChipPm, a panmicrobial microarray comprising 29,455 sixty-mer oligonucleotide probes for vertebrate viruses, bacteria, fungi, and parasites. Methods for nucleic acid preparation, random primed PCR amplification, and labeling were optimized to allow the sensitivity required for application with nucleic acid extracted from clinical materials and cultured isolates. Analysis of nasopharyngeal aspirates, blood, urine, and tissue from persons with various infectious diseases confirmed the presence of viruses and bacteria identified by other methods, and implicated Plasmodium falciparum in an unexplained fatal case of hemorrhagic feverlike disease during the Marburg hemorrhagic fever outbreak in Angola in 2004–2005.