Pathogenesis of Chapare virus in cynomolgus macaques.

Chapare virus (CHAPV) is an emerging New World arenavirus that is the causative agent of Chapare haemorrhagic fever (CHHF) responsible for recent outbreaks with alarmingly high case fatality rates in Bolivia near the Brazilian border. Here, we describe a nonhuman primate (NHP) model of CHHF infection which represents an essential tool to understand this emerging biological threat agent. Cynomolgus macaques challenged intravenously with CHAPV develop clinical disease, which recapitulates several key features of human CHHF.

Safety Toxicology Study of Reassortant Mopeia-Lassa Vaccine in Guinea Pigs.

Background: (1)Mopeia-Lassa reassortant ML29 virus is an investigational, reassortant virus vaccine for the prevention of Lassa fever caused by Lassa virus (LASV).

Methods: (2)The vaccine virus ML29-SF was prepared in Vero cells using a serum-free culture medium under Good Manufacturing Practice. A 2-week repeat dose toxicity study was performed in guinea pigs under Good Laboratory Practice (GLP) regulations to assess the local and systemic toxicological effects.

Lassa virus protein-protein interactions as mediators of Lassa fever pathogenesis.

Viral hemorrhagic Lassa fever (LF), caused by Lassa virus (LASV), is a significant public health concern endemic in West Africa with high morbidity and mortality rates, limited treatment options, and potential for international spread. Despite advances in interrogating its epidemiology and clinical manifestations, the molecular mechanisms driving pathogenesis of LASV and other arenaviruses remain incompletely understood. This review synthesizes current knowledge regarding the role of LASV host-virus interactions in mediating the pathogenesis of LF, with emphasis on interactions between viral and host proteins.

Natural History of Chapare Virus Infection in Strain 13 Guinea Pigs.

Chapare virus (CHAPV) is an emerging arenavirus first discovered in Bolivia. Clinical cases have a high case-fatality rate and a concerning capacity for person-to-person spread. Animal models of Chapare hemorrhagic fever are needed to study pathogenesis and development of medical counter measures.

Pathogenic and Apathogenic Strains of Lymphocytic Choriomeningitis Virus Have Distinct Entry and Innate Immune Activation Pathways.

Lymphocytic choriomeningitis virus (LCMV) and Lassa virus (LASV) share many genetic and biological features including subtle differences between pathogenic and apathogenic strains. Despite remarkable genetic similarity, the viscerotropic WE strain of LCMV causes a fatal LASV fever-like hepatitis in non-human primates (NHPs) while the mouse-adapted Armstrong (ARM) strain of LCMV is deeply attenuated in NHPs and can vaccinate against LCMV-WE challenge. Here, we demonstrate that internalization of WE is more sensitive to the depletion of membrane cholesterol than ARM infection while ARM infection is more reliant on endosomal acidification.

Single-Dose Immunogenic DNA Vaccines Coding for Live-Attenuated Alpha- and Flaviviruses.

Single-dose, immunogenic DNA (iDNA) vaccines coding for whole live-attenuated viruses are reviewed. This platform, sometimes called immunization DNA, has been used for vaccine development for flavi- and alphaviruses. An iDNA vaccine uses plasmid DNA to launch live-attenuated virus vaccines in vitro or in vivo.

Characterization of Ebola Virus Mucosal Challenge Routes in Cynomolgus Macaques.

(EBOV) causes Ebola virus disease (EVD), a devastating viral hemorrhagic fever in humans. Nonhuman primate (NHP) models of EVD traditionally use intramuscular infection with higher case fatality rates and reduced mean time-to-death compared to contact transmission typical of human cases of EVD. A cynomolgus macaque model of oral and conjunctival EBOV was used to further characterize the more clinically relevant contact transmission of EVD.

Evaluation of molnupiravir (EIDD-2801) efficacy against SARS-CoV-2 in the rhesus macaque model.

Molnupiravir (EIDD-2801) is a prodrug of a ribonucleoside analogue that is currently being used under a US FDA emergency use authorization for the treatment of mild to moderate COVID-19. We evaluated molnupiravir for efficacy as an oral treatment in the rhesus macaque model of SARS-CoV-2 infection. Twenty non-human primates (NHPs) were challenged with SARS-CoV-2 and treated with 75 mg/kg (n = 8) or 250 mg/kg (n = 8) of molnupiravir twice daily by oral gavage for 7 days.

Curriculum Guidelines for Graduate and Undergraduate Virology Courses.

Curriculum guidelines for virology are needed to best guide student learning due to the continuous and ever-increasing volume of virology information, the need to ensure that undergraduate and graduate students have a foundational understanding of key virology concepts, and the importance in being able to communicate that understanding to both other virologists and nonvirologists. Such guidelines, developed by virology educators and the American Society for Virology Education and Career Development Committee, are described herein.

Single dose rVSVΔG-JUNVGP vaccine protects guinea pigs against lethal Junin virus challenge.

Junin virus (JUNV) is a pathogen of biodefense importance due to its potential for aerosol transmission and mortality rates reaching 30%. Currently, there are no JUNV vaccines licensed by the United States Food and Drug Administration (FDA) for at-risk individuals. A vaccine based on recombinant vesicular stomatitis virus (rVSV) has been effectively used to prevent Ebola virus disease in humans.

Lassa Virus Vaccine Candidate ML29 Generates Truncated Viral RNAs Which Contribute to Interfering Activity and Attenuation.

Defective interfering particles (DIPs) are naturally occurring products during virus replication in infected cells. DIPs contain defective viral genomes (DVGs) and interfere with replication and propagation of their corresponding standard viral genomes by competing for viral and cellular resources, as well as promoting innate immune antiviral responses. Consequently, for many different viruses, including mammarenaviruses, DIPs play key roles in the outcome of infection.

Advanced Safety and Genetic Stability in Mice of a Novel DNA-Launched Venezuelan Equine Encephalitis Virus Vaccine with Rearranged Structural Genes.

The safety and genetic stability of V4020, a novel Venezuelan Equine Encephalitis Virus (VEEV) vaccine based on the investigational VEEV TC-83 strain, was evaluated in mice. V4020 was generated from infectious DNA, contains a stabilizing mutation in the E2-120 glycoprotein, and includes rearrangement of structural genes. After intracranial inoculation (IC), replication of V4020 was more attenuated than TC-83, as documented by low clinical scores, inflammation, viral load in brain, and earlier viral clearance.

Social Anxiety and Perceived Social Support: Gender Differences and the Mediating Role of Communication Styles.

Social anxiety has been linked with lower perceived social support, and there is some evidence that communication styles may explain this relationship. In addition, a body of literature has found gender differences in social anxiety, communication, and perceived social support. The purpose of this exploratory study was to investigate six communication styles as mediators of the relationship between social anxiety and perceived social support and whether such relationships vary by gender.

Fireworks and Seafood Boils: The Epidemiology of Burns in Louisiana.

Epidemiological trends provide a means for targeting efforts in burn prevention. There have been but few regional-specific studies concerning burns in the southern United States. This study describes burn injury trends experienced by a single burn center in Louisiana.

Novel DNA-launched Venezuelan equine encephalitis virus vaccine with rearranged genome.

Novel live-attenuated V4020 vaccine was prepared for Venezuelan equine encephalitis virus (VEEV), an alphavirus from the Togaviridae family. The genome of V4020 virus was rearranged, with the capsid gene expressed using a duplicate subgenomic promoter downstream from the glycoprotein genes. V4020 also included both attenuating mutations from the TC83 VEEV vaccine secured by mutagenesis to prevent reversion mutations.

Attenuated Replication of Lassa Virus Vaccine Candidate ML29 in STAT-1 Mice.

Lassa virus (LASV), a highly prevalent mammalian arenavirus endemic in West Africa, can cause Lassa fever (LF), which is responsible for thousands of deaths annually. LASV is transmitted to humans from naturally infected rodents. At present, there is not an effective vaccine nor treatment.