In 2022, mpox virus (MPXV) spread worldwide, causing 99,581 mpox cases in 121 countries. Modified vaccinia Ankara (MVA) vaccine use reduced disease in at-risk populations but failed to deliver complete protection. Lag in manufacturing and distribution of MVA resulted in additional MPXV spread, with 12,000 reported cases in 2023 and an additional outbreak in Central Africa of clade I virus.
View Article and Find Full Text PDFWe report strong Zika virus (ZIKV) neutralizing antibody responses in African green monkeys (Chlorocebus sabaeus) up to 1,427 days after ZIKV exposure via the subcutaneous, intravaginal, or intrarectal routes. Our results suggest that immunocompetent African green monkeys previously infected with ZIKV are likely protected from reinfection for years, possibly life, and would not contribute to virus amplification during ZIKV epizootics.
View Article and Find Full Text PDFSmallpox was the most rampant infectious disease killer of the 20th century, yet much remains unknown about the pathogenesis of the variola virus. Using archived tissue from a study conducted at the Centers for Disease Control and Prevention we characterized pathology in 18 cynomolgus macaques intravenously infected with the Harper strain of variola virus. Six macaques were placebo-treated controls, six were tecovirimat-treated beginning at 2 days post-infection, and six were tecovirimat-treated beginning at 4 days post-infection.
View Article and Find Full Text PDFThe 2022 global human monkeypox outbreak emphasizes the importance of maintaining poxvirus research, including enriching a basic understanding of animal models for developing and advancing therapeutics and vaccines. Intravenous administration of monkeypox virus in macaques is arguably one of the best animal models for evaluating the efficacy of medical countermeasures. Here we addressed one criticism of the model, a requirement for a high-titer administration of virus, as well as improving our understanding of monkeypox virus pathogenesis.
View Article and Find Full Text PDFFor over two decades, researchers have sought to improve smallpox vaccines and also develop therapies to ensure protection against smallpox or smallpox-like disease. The 2022 human monkeypox pandemic is a reminder that these efforts should persist. Advancing such therapies have involved animal models primarily using surrogate viruses such as monkeypox virus.
View Article and Find Full Text PDFDisease associated with Nipah virus infection causes a devastating and often fatal spectrum of syndromes predominated by both respiratory and neurologic conditions. Additionally, neurologic sequelae may manifest months to years later after virus exposure or apparent recovery. In the two decades since this disease emerged, much work has been completed in an attempt to understand the pathogenesis and facilitate development of medical countermeasures.
View Article and Find Full Text PDFEbola virus remains a significant public health concern due to high morbidity and mortality rates during recurrent outbreaks in endemic areas. Therefore, the development of countermeasures against Ebola virus remains a high priority, and requires the availability of appropriate animal models for efficacy evaluations. The most commonly used nonhuman primate models for efficacy evaluations against Ebola virus utilize the intramuscular or aerosol route of exposure.
View Article and Find Full Text PDFMost alphaviruses are mosquito-borne and can cause severe disease in humans and domesticated animals. In North America, eastern equine encephalitis virus (EEEV) is an important human pathogen with case fatality rates of 30-90%. Currently, there are no therapeutics or vaccines to treat and/or prevent human infection.
View Article and Find Full Text PDFEbola virus is a continuing threat to human populations, causing a virulent hemorrhagic fever disease characterized by dysregulation of both the innate and adaptive host immune responses. Severe cases are distinguished by an early, elevated pro-inflammatory response followed by a pronounced lymphopenia with B and T cells unable to mount an effective anti-viral response. The precise mechanisms underlying the dysregulation of the host immune system are poorly understood.
View Article and Find Full Text PDFAirborne transmission is predicted to be a prevalent route of human exposure with SARS-CoV-2. Aside from African green monkeys, nonhuman primate models that replicate airborne transmission of SARS-CoV-2 have not been investigated. A comparative evaluation of COVID-19 in African green monkeys, rhesus macaques, and cynomolgus macaques following airborne exposure to SARS-CoV-2 was performed to determine critical disease parameters associated with disease progression, and establish correlations between primate and human COVID-19.
View Article and Find Full Text PDFWe modeled the stability of SARS-CoV-2 on apples, tomatoes, and jalapeño peppers at two temperatures following a low-dose aerosol exposure designed to simulate an airborne transmission event involving droplet nuclei. Infectious virus was not recovered postexposure.
View Article and Find Full Text PDFMosquito-borne and sexual transmission of Zika virus (ZIKV), a TORCH pathogen, recently initiated a series of large epidemics throughout the Tropics. Animal models are necessary to determine transmission risk and study pathogenesis, as well screen antivirals and vaccine candidates. In this study, we modeled mosquito and sexual transmission of ZIKV in the African green monkey (AGM).
View Article and Find Full Text PDFWe explored an emerging technology to produce anti-Hantaan virus (HTNV) and anti-Puumala virus (PUUV) neutralizing antibodies for use as pre- or post-exposure prophylactics. The technology involves hyperimmunization of transchomosomic bovines (TcB) engineered to express human polyclonal IgG antibodies with HTNV and PUUV DNA vaccines encoding GG glycoproteins. For the anti-HTNV product, TcB was hyperimmunized with HTNV DNA plus adjuvant or HTNV DNA formulated using lipid nanoparticles (LNP).
View Article and Find Full Text PDFRecent Ebola virus (EBOV) outbreaks in West Africa and the Democratic Republic of the Congo have highlighted the urgent need for approval of medical countermeasures for treatment and prevention of EBOV disease (EVD). Until recently, when successes were achieved in characterizing the efficacy of multiple experimental EVD therapeutics in humans, the only feasible way to obtain data regarding potential clinical benefits of candidate therapeutics was by conducting well-controlled animal studies. Nonclinical studies are likely to continue to be important tools for screening and development of new candidates with improved pharmacological properties.
View Article and Find Full Text PDFProton radiation therapy has been used clinically since 1952, and major advancements in the last 10 years have helped establish protons as a major clinical modality in the cancer-fighting arsenal. Technologies will always evolve, but enough major breakthroughs have been accomplished over the past 10 years to allow for a major revolution in proton therapy. This paper summarizes the major technology advancements with respect to beam delivery that are now ready for mass implementation in the proton therapy space and encourages vendors to bring these to market to benefit the cancer population worldwide.
View Article and Find Full Text PDFCrimean-Congo hemorrhagic fever (CCHF) is the most medically important tick-borne viral disease of humans and tuberculosis is the leading cause of death worldwide by a bacterial pathogen. These two diseases overlap geographically, however, concurrent infection of CCHF virus (CCHFV) with mycobacterial infection has not been assessed nor has the ability of virus to persist and cause long-term sequela in a primate model. In this study, we compared the disease progression of two diverse strains of CCHFV in the recently described cynomolgus macaque model.
View Article and Find Full Text PDFHantaan virus (HTNV) and Puumala virus (PUUV) are rodent-borne hantaviruses that are the primary causes of hemorrhagic fever with renal syndrome (HFRS) in Europe and Asia. The development of well characterized animal models of HTNV and PUUV infection is critical for the evaluation and the potential licensure of HFRS vaccines and therapeutics. In this study we present three animal models of HTNV infection (hamster, ferret and marmoset), and two animal models of PUUV infection (hamster, ferret).
View Article and Find Full Text PDFConcerns regarding outbreaks of human monkeypox or the potential reintroduction of smallpox into an immunological naïve population have prompted the development of animal models and countermeasures. Here we present a marmoset model of monkeypox and smallpox disease utilizing a relevant poxvirus via a natural exposure route. We found that 1000 plaque forming units (PFU) of Monkeypox virus was sufficient to recapitulate smallpox disease, to include an incubation period of approximately 13 days, followed by the onset of rash, and death between 15 and 17 days.
View Article and Find Full Text PDFRift Valley fever virus (RVFV) is an important mosquito-borne veterinary and human pathogen that has caused large outbreaks of severe disease throughout Africa and the Arabian Peninsula. Currently, no licensed vaccine or therapeutics exists to treat this potentially deadly disease. The explosive nature of RVFV outbreaks and the severe consequences of its accidental or intentional introduction into RVFV-free areas provide the impetus for the development of novel vaccine candidates for use in both livestock and humans.
View Article and Find Full Text PDFEbola virus disease (EVD), caused by Ebola virus (EBOV), is a severe illness characterized by case fatality rates of up to 90%. The sporadic nature of outbreaks in resource-limited areas has hindered the ability to characterize the pathogenesis of EVD at all stages of infection but particularly early host responses. Pathogenesis is often studied in nonhuman primate (NHP) models of disease that replicate major aspects of human EVD.
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