Skip to main content

Genomic and #Clinical #Analysis of a #Fatal Human #Lyssavirus irkut Case: Evidence for a Natural Focus in the Russian Far East

Image
By G.M.

Abstract

In this report, we document and analyze a case in which the Irkut virus (IRKV) (Mononegavirales: Rhabdoviridae) caused a fatal human case following a bat bite in June 2021. Unfortunately, the available data did not permit a detailed taxonomic classification of the carrier bat (Chiroptera). The event occurred in the southwestern part of the Sikhote-Alin mountain region (Russian Far East) covered by the Ussuri taiga forest. The symptoms of the illness began with the following: fever; pronounced psychomotor and motor agitation; tremor of the lower jaw and tongue; aphasia; dyslexia; and dysphagia. These rapidly developed, leading to a severe and fatal encephalitis. The patient was not vaccinated for rabies and did not receive rabies immunoglobulin. Using brain sections prepared from the deceased, molecular diagnostics were performed: immunofluorescence (polyclonal anti-rabies immunoglobulin) indicating the presence of the lyssavirus antigen; and RT-PCR indicating traces of viral RNA. Sectional material (brain) was used for whole-genome sequencing, resulting in a near-complete sequence of the lyssavirus genome. The obtained genomic sequence was identified as the Irkut virus. A comparative analysis of the new sequence and other currently available IRKV sequences (NCBI) revealed differences. Specifically, amino acid differences between antigenic sites in the isolate and those of the rabies vaccine strain used regionally were noted. The patient history and subsequent analysis confirm human IRKV infection following bat contact. Like other fatal cases of IRKV infection described earlier, this case occurred in the southern part of the Russian Far East. Two have occurred in the southwestern part of the Sikhote-Alin mountain region. This indicates the possible existence of an active, natural viral focus.

Source: Viruses, https://www.mdpi.com/1999-4915/17/6/769

____

Labels:

Comments

Post a Comment

Popular posts from this blog

#Neuroinvasive #Oropouche virus in a patient with #HIV from extra-Amazonian #Brazil

By G.M.
{Excerpt} A novel reassortant Oropouche virus (OROV) lineage (with medium [M], large [L], and small [S] RNA segments : M1L2S2) has driven Brazil's largest and most geographically widespread OROV epidemic , expanding beyond the endemic Amazon basin to establish local transmission across multiple Brazilian states and other previously unaffected Latin American countries . The rapid spread of this lineage underscores its evolutionary potential and reinforces its significance as a public health threat .1 Similar to chikungunya and Zika viruses, expanding arboviruses can exhibit unexpected clinical and epidemiological shifts , including vertical transmissions , neuroinvasive effects, and potentially fatal outcomes.2–4 Although OROV typically causes self-limited febrile illness, accumulating clinical and experimental evidence suggests neurotropic potential .5 This Correspondence describes the first confirmed case of neuroinvasive OROV infection caused by the emergent M1L2S2 lineage in ext...
Post a Comment
Read more »

No evidence of immune #exhaustion after repeated #SARS-CoV-2 #vaccination in vulnerable and healthy populations

By G.M.
Abstract Frequent SARS-CoV-2 vaccination in vulnerable populations has raised concerns that this may contribute to T cell exhaustion , which could negatively affect the quality of immune protection. Herein, we examined the impact of repeated SARS-CoV-2 vaccination on T cell phenotypic and functional exhaustion in frail older adults in long-term care (n = 23), individuals on immunosuppressive drugs (n = 10), and healthy adults (n = 43), in Canada . Spike-specific CD4+ and CD8+ T cell levels did not decline in any cohort following repeated SARS-CoV-2 vaccination, nor did the expression of exhaustion markers on spike-specific or total T cells increase. T cell production of multiple cytokines (i.e. polyfunctionality) in response to the spike protein of SARS-CoV-2 did not decline in any cohort following repeated vaccination. None of the cohorts displayed elevated levels of terminally differentiated T cells following multiple SARS-CoV-2 vaccinations. Thus, repeated SARS-CoV-2 vaccination was...
Post a Comment
Read more »

Chimeric #hemagglutinin and #M2 #mRNA #vaccine for broad #influenza subtype protection

By G.M.
Abstract Since multiple and unpredicted influenza viruses cause seasonal epidemics and even high-risk pandemics , developing a universal influenza vaccine is essential to provide broad protection against various influenza subtypes. Combined with the mRNA lipid nanoparticle-encapsulated (mRNA-LNP) vaccine platform and chimeric immunogen strategy , we developed a novel cocktail mRNA vaccine encoding chimeric HAs (cH5/1-BV, cH7/3) and intact M2 (termed Fluaxe), which confers broad protection against major circulating IAVs and IBVs , as well as highly pathogenic avian influenza . Two-dose intramuscular immunization of Fluaxe in mice elicited cross-reactive neutralizing antibodies , T cell responses, and long-lived immunity, resulting in robust protection against multiple lethal influenza virus infections and severe acute lung injuries . In particular, intramuscular administration stimulated systemic immunity together with a prominent lung tropism of memory cells . Moreover, Fluaxe immuniza...
Post a Comment
Read more »