Differential pathogenesis of closely related 2018 Nigerian outbreak clade III Lassa virus isolates.

Nigeria continues to experience ever increasing annual outbreaks of Lassa fever (LF). The World Health Organization has recently declared Lassa virus (LASV) as a priority pathogen for accelerated research leading to a renewed international effort to develop relevant animal models of disease and effective countermeasures to reduce LF morbidity and mortality in endemic West African countries. A limiting factor in evaluating medical countermeasures against LF is a lack of well characterized animal models outside of those based on infection with LASV strain Josiah originating form Sierra Leone, circa 1976.

Hantavirus Cardiopulmonary Syndrome in Canada.

Hantavirus cardiopulmonary syndrome (HCPS) is a severe respiratory disease caused by Sin Nombre virus in North America (SNV). As of January 1, 2020, SNV has caused 143 laboratory-confirmed cases of HCPS in Canada. We review critical aspects of SNV virus epidemiology and the ecology, biology, and genetics of HCPS in Canada.

Oseltamivir Is Effective against 1918 Influenza Virus Infection of Macaques but Vulnerable to Escape.

The 1918 influenza virus, subtype H1N1, was the causative agent of the most devastating pandemic in the history of infectious diseases. studies have confirmed that extreme virulence is an inherent property of this virus. Here, we utilized the macaque model for evaluating the efficacy of oseltamivir phosphate against the fully reconstructed 1918 influenza virus in a highly susceptible and relevant disease model.

Impact of intensive care unit supportive care on the physiology of Ebola virus disease in a universally lethal non-human primate model.

Background: There are currently limited data for the use of specific antiviral therapies for the treatment of Ebola virus disease (EVD). While there is anecdotal evidence that supportive care may be effective, there is a paucity of direct experimental data to demonstrate a role for supportive care in EVD. We studied the impact of ICU-level supportive care interventions including fluid resuscitation, vasoactive medications, blood transfusion, hydrocortisone, and ventilator support on the pathophysiology of EVD in rhesus macaques infected with a universally lethal dose of Ebola virus strain Makona C07.

The interaction between the Nipah virus nucleocapsid protein and phosphoprotein regulates virus replication.

Continued outbreaks of Henipaviruses in South Asia and Australia cause severe and lethal disease in both humans and animals. Together, with evidence of human to human transmission for Nipah virus and the lack of preventative or therapeutic measures, its threat to cause a widespread outbreak and its potential for weaponization has increased. In this study we demonstrate how overexpression of the Nipah virus nucleocapsid protein regulates viral polymerase activity and viral RNA production.

Seroprevalence of Rift Valley Fever Virus Antibodies in Cattle in Mali, 2005-2014.

Rift Valley fever virus (RVFV) outbreaks have considerable impact on human and animal health. Here, we are reporting a serosurvey of cattle from all regions of Mali. These demonstrated that few had been exposed to RVFV from 2005 to 2014.

Real-Time and End-Point PCR Diagnostics for Ebola Virus.

Reverse transcriptase polymerase chain reaction (RT-PCR)-based techniques allow for highly sensitive and specific detection of RNA viruses. Detection of the amplification products can be achieved using several methods. The following are descriptions of the detection of ebolavirus RNA using end-point RT-PCR (agarose gel visualization of amplification products) and quantitative RT-PCR (Q-RT-PCR), with fluorescent detection using an intercalating dye or detection with the use of 5' hydrolysis probe assays.

Delivering Prolonged Intensive Care to a Non-human Primate: A High Fidelity Animal Model of Critical Illness.

Critical care needs have been rising in recent decades as populations age and comorbidities increase. Sepsis-related admissions to critical care contribute up to 50% of volume and septic shock carries a 35-54% fatality rate. Improvements in sepsis-related care and mortality would have a significant impact of a resource-intensive area of health care delivery.

Inactivation of Zaire ebolavirus Variant Makona in Human Serum Samples Analyzed by Enzyme-Linked Immunosorbent Assay.

Personnel deployed to remote areas during infectious disease outbreaks have limited access to mechanical and chemical inactivation resources. The inactivation of infectious agents present in diagnostic samples is critical to ensure the safety of personnel and the containment of the disease. We evaluated the efficacy of thermal inactivation (exposure to 56°C for 1 hour) and chemical inactivation with 0.

Plasmodium Parasitemia Associated With Increased Survival in Ebola Virus-Infected Patients.

Background: The ongoing Ebola outbreak in West Africa has resulted in 28 646 suspected, probable, and confirmed Ebola virus infections. Nevertheless, malaria remains a large public health burden in the region affected by the outbreak. A joint Centers for Disease Control and Prevention/National Institutes of Health diagnostic laboratory was established in Monrovia, Liberia, in August 2014, to provide laboratory diagnostics for Ebola virus.

Ebola Laboratory Response at the Eternal Love Winning Africa Campus, Monrovia, Liberia, 2014-2015.

West Africa experienced the first epidemic of Ebola virus infection, with by far the greatest number of cases in Guinea, Sierra Leone, and Liberia. The unprecedented epidemic triggered an unparalleled response, including the deployment of multiple Ebola treatment units and mobile/field diagnostic laboratories. The National Institute of Allergy and Infectious Diseases and the Centers for Disease Control and Prevention deployed a joint laboratory to Monrovia, Liberia, in August 2014 to support the newly founded Ebola treatment unit at the Eternal Love Winning Africa (ELWA) campus.

The Merits of Malaria Diagnostics during an Ebola Virus Disease Outbreak.

Malaria is a major public health concern in the countries affected by the Ebola virus disease epidemic in West Africa. We determined the feasibility of using molecular malaria diagnostics during an Ebola virus disease outbreak and report the incidence of Plasmodium spp. parasitemia in persons with suspected Ebola virus infection.

Quantitative serology assays for determination of antibody responses to Ebola virus glycoprotein and matrix protein in nonhuman primates and humans.

The West Africa Ebola virus disease (EVD) outbreak has reached unprecedented magnitude and caused worldwide concerns for the spread of this deadly virus. Recent findings in nonhuman primates (NHPs) demonstrate that antibodies can be protective against EVD. However, the role of antibody response in vaccine-mediated protection is not fully understood.

Analytical Performance Characteristics of the Cepheid GeneXpert Ebola Assay for the Detection of Ebola Virus.

Background: The recently developed Xpert® Ebola Assay is a novel nucleic acid amplification test for simplified detection of Ebola virus (EBOV) in whole blood and buccal swab samples. The assay targets sequences in two EBOV genes, lowering the risk for new variants to escape detection in the test. The objective of this report is to present analytical characteristics of the Xpert® Ebola Assay on whole blood samples.

Ebola viral load at diagnosis associates with patient outcome and outbreak evolution.

Background: Ebola virus (EBOV) causes periodic outbreaks of life-threatening EBOV disease in Africa. Historically, these outbreaks have been relatively small and geographically contained; however, the magnitude of the EBOV outbreak that began in 2014 in West Africa has been unprecedented. The aim of this study was to describe the viral kinetics of EBOV during this outbreak and identify factors that contribute to outbreak progression.

The Contribution of Ebola Viral Load at Admission and Other Patient Characteristics to Mortality in a Médecins Sans Frontières Ebola Case Management Centre, Kailahun, Sierra Leone, June-October 2014.

This paper describes patient characteristics, including Ebola viral load, associated with mortality in a Médecins Sans Frontières Ebola case management centre (CMC).Out of 780 admissions between June and October 2014, 525 (67%) were positive for Ebola with a known outcome. The crude mortality rate was 51% (270/525).

Transmission of Ebola viruses: what we know and what we do not know.

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.

Evaluation of transmission risks associated with in vivo replication of several high containment pathogens in a biosafety level 4 laboratory.

Containment level 4 (CL4) laboratories studying biosafety level 4 viruses are under strict regulations to conduct nonhuman primate (NHP) studies in compliance of both animal welfare and biosafety requirements. NHPs housed in open-barred cages raise concerns about cross-contamination between animals, and accidental exposure of personnel to infectious materials. To address these concerns, two NHP experiments were performed.