Evaluation of waning of IgG antibody responses after rVSVΔG-ZEBOV-GP and Ad26.ZEBOV, MVA-BN-Filo Ebola virus disease vaccines: a modelling study from the PREVAC randomized trial.

rVSVΔG-ZEBOV-GP and Ad26.ZEBOV, MVA-BN-Filo are WHO-prequalified vaccination regimens against Ebola virus disease (EVD). Challenges associated with measuring long-term clinical protection warrant the evaluation of immune response kinetics after vaccination.

The deployment of mobile diagnostic laboratories for Ebola virus disease diagnostics in Sierra Leone and Guinea.

Background: Ebola virus emerged in West Africa in December 2013. The ease of mobility, porous borders, and lack of public health infrastructure led to the largest Ebola virus disease (EVD) outbreak to date.

Intervention: The 2013 EVD outbreak signalled the need for laboratory diagnostic capabilities in areas without strong public health systems.

The first epidemiological and virological influenza surveillance in the Republic of Guinea revealed the predominance of influenza A/H3N2 and B Victoria viruses.

Little is known about respiratory viruses infection in Guinea. Influenza surveillance has not been implemented in Guinea mainly because of the paucity of laboratory infrastructure and capacity. This paper presents the first influenza surveillance data in Guinea.

Longitudinal antibody and T cell responses in Ebola virus disease survivors and contacts: an observational cohort study.

Background: The 2013-16 Ebola virus disease epidemic in west Africa caused international alarm due to its rapid and extensive spread resulting in a significant death toll and social unrest within the affected region. The large number of cases provided an opportunity to study the long-term kinetics of Zaire ebolavirus-specific immune response of survivors in addition to known contacts of those infected with the virus.

Methods: In this observational cohort study, we worked with leaders of Ebola virus disease survivor associations in two regions of Guinea, Guéckédou and Coyah, to recruit survivors of Ebola virus disease, contacts from households of individuals known to have had Ebola virus disease, and individuals who were not knowingly associated with infected individuals or had not had Ebola virus disease symptoms to serve as negative controls.

A 40-Month Follow-Up of Ebola Virus Disease Survivors in Guinea (PostEbogui) Reveals Long-Term Detection of Ebola Viral Ribonucleic Acid in Semen and Breast Milk.

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.

Creating a National Specimen Referral System in Guinea: Lessons From Initial Development and Implementation.

In the wake of the 2014-2016, West Africa Ebola virus disease (EVD) outbreak, the Government of Guinea recognized an opportunity to strengthen its national laboratory system, incorporating capacity and investments developed during the response. The Ministry of Health (MOH) identified creation of a holistic, safe, secure, and timely national specimen referral system as a priority for improved detection and confirmation of priority diseases, in line with national Integrated Disease Surveillance and Response guidelines. The project consisted of two parts, each led by different implementing partners working collaboratively together and with the Ministry of Health: the development and approval of a national specimen referral policy, and pilot implementation of a specimen referral system, modeled on the policy, in three prefectures.

Assessing health systems in Guinea for prevention and control of priority zoonotic diseases: A One Health approach.

To guide One Health capacity building efforts in the Republic of Guinea in the wake of the 2014-2016 Ebola virus disease (EVD) outbreak, we sought to identify and assess the existing systems and structures for zoonotic disease detection and control. We partnered with the government ministries responsible for human, animal, and environmental health to identify a list of zoonotic diseases - rabies, anthrax, brucellosis, viral hemorrhagic fevers, trypanosomiasis and highly pathogenic avian influenza - as the country's top priorities. We used each priority disease as a case study to identify existing processes for prevention, surveillance, diagnosis, laboratory confirmation, reporting and response across the three ministries.

Serological Evidence of Ebola Virus Infection in Rural Guinea before the 2014 West African Epidemic Outbreak.

Questions remain as to whether an unnoticed Ebola outbreak occurred in Guinea before the 2014-2016 epidemic. To address this, we used a highly sensitive and specific Luminex-based assay for Ebola virus (EBOV) antibody detection to screen blood samples collected in the framework of the Demographic Health Survey performed in 2012 in Guinea. One sample (GF069) of 1,483 tested was positive at very high immunoglobulin G titer to Zaire EBOV in Guinée Forestière.

Dynamics of cholera epidemics from Benin to Mauritania.

Background: The countries of West Africa are largely portrayed as cholera endemic, although the dynamics of outbreaks in this region of Africa remain largely unclear.

Methodology/principal Findings: To understand the dynamics of cholera in a major portion of West Africa, we analyzed cholera epidemics from 2009 to 2015 from Benin to Mauritania. We conducted a series of field visits as well as multilocus variable tandem repeat analysis and whole-genome sequencing analysis of V.

Infection prevention and control training and capacity building during the Ebola epidemic in Guinea.

Background: During the 2014-2016 Ebola epidemic in West Africa, a key epidemiological feature was disease transmission within healthcare facilities, indicating a need for infection prevention and control (IPC) training and support.

Methods: IPC training was provided to frontline healthcare workers (HCW) in healthcare facilities that were not Ebola treatment units, as well as to IPC trainers and IPC supervisors placed in healthcare facilities. Trainings included both didactic and hands-on components, and were assessed using pre-tests, post-tests and practical evaluations.

Sensitivity, Specificity, and Public-Health Utility of Clinical Case Definitions Based on the Signs and Symptoms of Cholera in Africa.

During 2014, Africa reported more than half of the global suspected cholera cases. Based on the data collected from seven countries in the African Cholera Surveillance Network (Africhol), we assessed the sensitivity, specificity, and positive and negative predictive values of clinical cholera case definitions, including that recommended by the World Health Organization (WHO) using culture confirmation as the gold standard. The study was designed to assess results in real-world field situations in settings with recent cholera outbreaks or endemicity.

Temporo-spatial dynamics and behavioural patterns of 2012 cholera epidemic in the African mega-city of Conakry, Guinea.

Background: Cholera is endemic in Guinea, having suffered consecutive outbreaks from 2004 to 2008 followed by a lull until the 2012 epidemic. Here we describe the temporal-spatial and behavioural characteristics of cholera cases in Conakry during a three-year period, including the large-scale 2012 epidemic.

Methods: We used the national and African Cholera Surveillance Network (Africhol) surveillance data collected from every cholera treatment centre in Conakry city from August 2011 to December 2013.

Operational evaluation of rapid diagnostic testing for Ebola Virus Disease in Guinean laboratories.

Background: Rapid Diagnostic Tests (RDTs) for Ebola Virus Disease (EVD) at the point of care have the potential to increase access and acceptability of EVD testing and the speed of patient isolation and secure burials for suspect cases. A pilot program for EVD RDTs in high risk areas of Guinea was introduced in October 2015. This paper presents concordance data between EVD RDTs and PCR testing in the field as well as an assessment of the acceptability, feasibility, and quality assurance of the RDT program.

Implementation of broad screening with Ebola rapid diagnostic tests in Forécariah, Guinea.

Background: Laboratory-enhanced surveillance is critical for rapidly detecting the potential re-emergence of Ebola virus disease. Rapid diagnostic tests (RDT) for Ebola antigens could expand diagnostic capacity for Ebola virus disease.

Objectives: The Guinean National Coordination for Ebola Response conducted a pilot implementation to determine the feasibility of broad screening of patients and corpses with the OraQuick Ebola RDT.

Different features of Vδ2 T and NK cells in fatal and non-fatal human Ebola infections.

Background: Human Ebola infection is characterized by a paralysis of the immune system. A signature of αβ T cells in fatal Ebola infection has been recently proposed, while the involvement of innate immune cells in the protection/pathogenesis of Ebola infection is unknown. Aim of this study was to analyze γδ T and NK cells in patients from the Ebola outbreak of 2014-2015 occurred in West Africa, and to assess their association with the clinical outcome.

Analysis of Diagnostic Findings From the European Mobile Laboratory in Guéckédou, Guinea, March 2014 Through March 2015.

Background: A unit of the European Mobile Laboratory (EMLab) consortium was deployed to the Ebola virus disease (EVD) treatment unit in Guéckédou, Guinea, from March 2014 through March 2015.

Methods: The unit diagnosed EVD and malaria, using the RealStar Filovirus Screen reverse transcription-polymerase chain reaction (RT-PCR) kit and a malaria rapid diagnostic test, respectively.

Results: The cleaned EMLab database comprised 4719 samples from 2741 cases of suspected EVD from Guinea.

Unique human immune signature of Ebola virus disease in Guinea.

Despite the magnitude of the Ebola virus disease (EVD) outbreak in West Africa, there is still a fundamental lack of knowledge about the pathophysiology of EVD. In particular, very little is known about human immune responses to Ebola virus. Here we evaluate the physiology of the human T cell immune response in EVD patients at the time of admission to the Ebola Treatment Center in Guinea, and longitudinally until discharge or death.

Spatial and temporal evolution of Lassa virus in the natural host population in Upper Guinea.

This study aimed at reconstructing the spatial and temporal evolution of Lassa virus (LASV) in the natural host population. To this end, we generated 132 partial nucleoprotein sequences of LASV from M. natalensis trapped in 12 villages around Faranah, Upper Guinea, over a period of 12 years.

Real-time, portable genome sequencing for Ebola surveillance.

The Ebola virus disease epidemic in West Africa is the largest on record, responsible for over 28,599 cases and more than 11,299 deaths. Genome sequencing in viral outbreaks is desirable to characterize the infectious agent and determine its evolutionary rate. Genome sequencing also allows the identification of signatures of host adaptation, identification and monitoring of diagnostic targets, and characterization of responses to vaccines and treatments.

Feasibility of Xpert Ebola Assay in Médecins Sans Frontières Ebola Program, Guinea.

Rapid diagnostic methods are essential in control of Ebola outbreaks and lead to timely isolation of cases and improved epidemiologic surveillance. Diagnosis during Ebola outbreaks in West Africa has relied on PCR performed in laboratories outside this region. Because time between sampling and PCR results can be considerable, we assessed the feasibility and added value of using the Xpert Ebola Assay in an Ebola control program in Guinea.

Use of Viremia to Evaluate the Baseline Case Fatality Ratio of Ebola Virus Disease and Inform Treatment Studies: A Retrospective Cohort Study.

Background: The case fatality ratio (CFR) of Ebola virus disease (EVD) can vary over time and space for reasons that are not fully understood. This makes it difficult to define the baseline CFRs needed to evaluate treatments in the absence of randomized controls. Here, we investigate whether viremia in EVD patients may be used to evaluate baseline EVD CFRs.