Publications by authors named "Eric J Sefing"

Article Synopsis
  • Five New World mammarenaviruses (NWMs) can cause serious hemorrhagic fever, and they enter human cells using the transferrin receptor 1 (hTfR1).
  • An antibody called ch128.1/IgG1 effectively blocks these viruses from infecting cells by targeting hTfR1 and preventing the viral GP1 protein from binding.
  • In tests, ch128.1/IgG1 also protected genetically modified mice from lethal NWMs and showed promise as a therapeutic option without significantly disrupting normal iron uptake.
View Article and Find Full Text PDF
Article Synopsis
  • Live-attenuated virus vaccines, like the Candid#1 strain for Junín virus (JUNV), are effective but pose risks of reverting to a pathogenic form, which has led to their lack of approval in the U.S.
  • A study found that a modified version of Candid#1, known as K33S rCan, is safe for guinea pigs, generates strong immune responses, and protects against lethal JUNV infections.
  • Genetic analysis showed that K33S rCan does not revert to virulence in neonatal mice, indicating its potential as a safe second-generation vaccine for JUNV.
View Article and Find Full Text PDF
Article Synopsis
  • - Junín virus (JUNV) is a dangerous virus causing Argentine hemorrhagic fever (AHF), with its disease mechanisms not fully understood, but a high interferon-α (IFN-α) response correlates with worse outcomes.
  • - Mice engineered to express the human transferrin receptor 1 (hTfR1) develop severe illness when infected with JUNV, marked by increased levels of serum IFN-α.
  • - The study reveals that both the entry of JUNV through hTfR1 and the activation of the type I IFN response are crucial in causing severe disease in these mice, highlighting potential pathways for understanding and treating AHF.
View Article and Find Full Text PDF
Article Synopsis
  • - Rift Valley fever virus (RVFV) is a mosquito-borne virus found in sub-Saharan Africa and the Arabian Peninsula, and currently, there are no approved treatments or vaccines for severe infections in humans.
  • - Galidesivir (BCX4430) is an antiviral drug that has shown effectiveness against over 20 viruses in lab tests and was tested in hamsters for its ability to combat RVFV infection.
  • - The study found that administering galidesivir either intramuscularly or intraperitoneally significantly improved survival rates in infected hamsters and reduced the presence of the virus in various organs, suggesting it could be a viable treatment for severe RVFV and similar diseases.
View Article and Find Full Text PDF
Article Synopsis
  • Old and New World arenaviruses cause viral hemorrhagic fever, leading to severe symptoms like bleeding, fluid loss, and organ failure, with limited treatment options available.
  • Researchers modified favipiravir treatment to include a high-dose loading period, achieving complete protection in guinea pigs from Argentine hemorrhagic fever when treatment started two days after infection.
  • This new strategy not only protected some animals even when treatment was delayed but also significantly reduced virus levels in their bodies, marking a breakthrough in using small molecule antivirals against deadly JUNV infections.
View Article and Find Full Text PDF
Article Synopsis
  • Favipiravir is approved in Japan for treating influenza and is effective against various RNA viruses, including Ebola; ribavirin is another licensed drug with similar activity.
  • Studies show that favipiravir and ribavirin work together to effectively inhibit bunyavirus infections in cell cultures and laboratory animals, possibly due to their different ways of functioning.
  • Research indicates that combining a low dose of ribavirin with favipiravir enhances its effectiveness against Junin virus in guinea pigs and Pichinde virus in hamsters, showing promise for treating hemorrhagic fever viruses.
View Article and Find Full Text PDF

Favipiravir (T-705) is a new anti-influenza drug approved for human use in Japan and progressing through Phase 3 clinical trials in the U.S. In addition to its potent inhibitory effects against influenza virus infection, the compound has been shown to be broadly active against RNA viruses from 9 different families, including the Arenaviridae.

View Article and Find Full Text PDF
Article Synopsis
  • - Rift Valley fever virus (RVFV) can cause serious health issues like hemorrhagic fever and has a high fatality rate in hospitalized patients; currently, there are no vaccines or treatments approved for human use.
  • - Research on a modified vaccine strain, rMP12-C13type, showed promising results, providing significant protection in hamsters when administered shortly after RVFV infection, unlike the standard MP-12 vaccine.
  • - The study indicates that the truncated NSs protein in rMP12-C13type may enhance the immune response, allowing for effective post-exposure vaccination and suggesting a longer time frame for potential prophylaxis against RVFV infections.
View Article and Find Full Text PDF
Article Synopsis
  • Rift Valley fever virus (RVFV) poses a significant health risk to humans and animals, is transmitted through various means, and currently lacks approved vaccines or treatments.
  • The study evaluates DEF201, an adenovirus-vectored interferon alpha, which provides a potential pre- and post-exposure treatment option in a hamster model of RVFV infection.
  • Administration of DEF201 intranasally showed complete protection from RVFV even when given shortly before exposure, while post-exposure treatment was effective within 6 hours but not later, indicating its promise as a countermeasure against RVFV.
View Article and Find Full Text PDF

Background: Junín virus (JUNV), the etiologic agent of Argentine hemorrhagic fever (AHF), is classified by the NIAID and CDC as a Category A priority pathogen. Presently, antiviral therapy for AHF is limited to immune plasma, which is readily available only in the endemic regions of Argentina. T-705 (favipiravir) is a broadly active small molecule RNA-dependent RNA polymerase inhibitor presently in clinical evaluation for the treatment of influenza.

View Article and Find Full Text PDF

Background: Tacaribe virus (TCRV) is a less biohazardous relative of the highly pathogenic clade B New World arenaviruses that cause viral hemorrhagic fever syndromes and require handling in maximum containment facilities not readily available to most researchers. AG129 type I and II interferon receptor knockout mice have been shown to be susceptible to TCRV infection, but the pathogenic mechanisms contributing to the lethal disease are unclear.

Methods: To gain insights into the pathogenesis of TCRV infection in AG129 mice, we assessed hematologic and cytokine responses during the course of infection, as well as changes in the permeability of the vascular endothelium.

View Article and Find Full Text PDF

Background: Junín virus (JUNV) and several other clade B New World arenaviruses cause human disease ranging from mild febrile illness to severe viral haemorrhagic fever. These viruses pose a significant threat to national security and safe and effective therapies are limited except in Argentina, where immune plasma is the standard of care for treating JUNV infection in cases of Argentine haemorrhagic fever.

Methods: An in vitro screen of the Chemtura library identified several compounds with activity against Tacaribe virus (TCRV), a clade B arenavirus closely related to JUNV.

View Article and Find Full Text PDF

Punta Toro virus (PTV; Bunyaviridae, Phlebovirus) is related to Rift Valley fever virus (RVFV), a pathogenic agent which causes severe disease in humans and livestock primarily in the sub-Saharan region of Africa. The recent range expansion of RVFV and the potential for its intentional release into naïve populations pose a significant threat to public health and agriculture. Studies modeling disease in rodents and nonhuman primates have shown that PTV and RVFV are highly sensitive to the antiviral effects of alpha interferon (IFN-α), an important component of the innate antiviral host response.

View Article and Find Full Text PDF

Several arenaviruses can cause viral hemorrhagic fever, a severe disease with case-fatality rates in hospitalized individuals ranging from 15-30%. Because of limited prophylaxis and treatment options, new medical countermeasures are needed for these viruses classified by the National Institutes of Allergy and Infectious Diseases (NIAID) as top priority biodefense Category A pathogens. Recombinant consensus interferon alpha (cIFN-α) is a licensed protein with broad clinical appeal.

View Article and Find Full Text PDF

Background: A growing number of arenaviruses can cause a devastating viral hemorrhagic fever (VHF) syndrome. They pose a public health threat as emerging viruses and because of their potential use as bioterror agents. All of the highly pathogenic New World arenaviruses (NWA) phylogenetically segregate into clade B and require maximum biosafety containment facilities for their study.

View Article and Find Full Text PDF