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[Progressive sensorineural hearing loss from infectious agents].

The progressive sensorineural hearing loss due to infectious causes can involve different etiological agents like bacteria, viruses, protozoons or mycetes. These infectious agents can act in various ways: directly through a labyrinthitis that may destroy the neuroepithelium; through an ischaemic process secondary to a septic embolus; or through a thrombus. In some cases the damage can occur in a meningitis context, because of the passage of the germ in the inner through the nerves, the vases or the labyrinthine liquids. Bacterial meningitis is one of the causes of progressive sensorinueral hea

How has Guinea learnt from the response to outbreaks? A learning health system analysis.

INTRODUCTION: Learning is a key attribute of a resilient health system and, therefore, is central to health system strengthening. The main objective of this study was to analyse how Guinea's health system has learnt from the response to outbreaks between 2014 and 2021. METHODS: We used a retrospective longitudinal single embedded case study design, applying the framework conceptualised by Sheikh and Abimbola for analysing learning health systems. Data were collected employing a mixed methods systematic review carried out in March 2022 and an online survey conducted in April 2022. RESULTS: Th

Differences in affinity of binding of lymphocytic choriomeningitis virus strains to the cellular receptor alpha-dystroglycan correlate with viral tropism and disease kinetics.

alpha-Dystroglycan (alpha-DG) was recently identified as a receptor for lymphocytic choriomeningitis virus (LCMV) and several other arenaviruses, including Lassa fever virus (W. Cao, M. D. Henry, P. Borrow, H. Yamada, J. H. Elder, E. V. Ravkov, S. T. Nichol, R. W. Compans, K. P. Campbell, and M. B. A. Oldstone, Science 282:2079-2081, 1998). Data presented in this paper indicate that the affinity of binding of LCMV to alpha-DG determines viral tropism and the outcome of infection in mice. To characterize this relationship, we evaluated the interaction between alpha-DG and several LCMV strains,

Rodent-borne infections in rural Ghanaian farming communities.

Rodents serve as reservoirs and/or vectors for several human infections of high morbidity and mortality in the tropics. Population growth an … ed. An in-house enzyme-linked immunosorbent assay (ELISA), for immunoglobulin G (IgG) antibodies to Lassa virus was positive in 34 (5%) of the human samples. Using commercial kits, antibodies to hantavirus serotypes, Puumala and Dobrava, and Leptospira bacteria were detected in 11%, 12% and 21% of the human samples, respectively. Forty percent of residents in …

Development of real-time reverse transcriptase qPCR assays for the detection of Punta Toro virus and Pichinde virus.

BACKGROUND: Research with high biocontainment pathogens such as Rift Valley fever virus (RVFV) and Lassa virus (LASV) is expensive, potentially hazardous, and limited to select institutions. Surrogate pathogens such as Punta Toro virus (PTV) for RVFV infection and Pichinde virus (PICV) for LASV infection allow research to be performed under more permissive BSL-2 conditions. Although used as infection models, PTV and PICV have no standard real-time RT-qPCR assays to detect and quantify pathogenesis. PTV is also a human pathogen, making a standardized detection assay essential for biosurveillanc…

Hearing Loss in COVID-19 Patients: An Audiological Profile of Symptomatic and Asymptomatic COVID-19 Patients in Qatar.

Background and objective Viral infections caused by cytomegalovirus, lymphocytic choriomeningitis virus, varicella-zoster virus, herpes simplex type 1 and type 2, rubella, measles, rubeola, HIV, West Nile virus, Lassa virus, and mumps are known to be associated with hearing loss. There have been reports of inner ear involvement in coronavirus disease 2019 (COVID-19) patients but the extent and variations in cochlear involvement of symptomatic and asymptomatic patients has not been adequately described. This study aimed to evaluate the hearing status among symptomatic and asymptomatic COVID-19 …

Chaperonin TRiC/CCT Participates in Mammarenavirus Multiplication in Human Cells via Interaction with the Viral Nucleoprotein.

The eukaryotic chaperonin containing tailless complex polypeptide 1 ring complex (CCT, also known as TCP-1 Ring Complex, TRiC/CCT) participates in the folding of 5% to 10% of the cellular proteome and has been involved in the life cycle of several viruses, including dengue, Zika, and influenza viruses, but the mechanisms by which the TRiC/CCT complex contributes to virus multiplication remain poorly understood. Here, we document that the nucleoprotein (NP) of the mammarenavirus lymphocytic choriomeningitis virus (LCMV) is a substrate of the human TRiC/CCT complex, and that pharmacological inhi

[Marburg, Lassa and Ebola viral hemorrhagic fevers (author's transl)].

For each of these three fevers recently described, the authors report the history of their identification. The features of the three viruses, and the clinical aspects of the diseases they induce, are also indicated. The laboratory diagnosis is described. Practical indications are given for the transportation of the specimens to the only three high security laboratories in the world. The laboratory diagnosis is described. Some cautions are indicated handling and treating patients. It must be envisaged also to organize a four degrees quarantive cautions; compulsory for necropsies, burials, and o

Pathways to health resilience: A cross-country analysis of health system response to re-emerging infectious diseases in Sub-Saharan Africa.

Sub-Saharan Africa (SSA) faces recurrent threats from re-emerging infectious diseases, including Ebola virus disease, cholera, measles, Lassa fever, and Marburg virus disease. This study assessed the resilience of health systems in 25 SSA countries from 2000 to 2023 using a multidimensional resilience index and a first-order Markov state-transition framework. Country-year observations were classified as Low Resilience, Moderate Resilience, or High Resilience based on epidemiological performance, health financing, surveillance, response capacity, and recovery indicators. Resilience was heteroge

Evolutionary analysis of Old World arenaviruses reveals a major adaptive contribution of the viral polymerase.

The Old World (OW) arenavirus complex includes several species of rodent-borne viruses, some of which (i.e., Lassa virus, LASV and Lymphocytic choriomeningitis virus, LCMV) cause human diseases. Most LCMV and LASV infections are caused by rodent-to-human transmissions. Thus, viral evolution is largely determined by events that occur in the wildlife reservoirs. We used a set of human- and rodent-derived viral sequences to investigate the evolutionary history underlying OW arenavirus speciation, as well as the more recent selective events that accompanied LASV spread in West Africa. We show that…

Characterization of the Glycoprotein Stable Signal Peptide in Mediating Pichinde Virus Replication and Virulence.

Arenaviruses can cause lethal hemorrhagic fevers in humans with few preventative and therapeutic measures. The arenaviral glycoprotein stable signal peptide (SSP) is unique among signal peptides in that it is an integral component of the mature glycoprotein complex (GPC) and plays important roles not only in GPC expression and processing but also in the membrane fusion process during viral entry. Using the Pichinde virus (PICV) reverse genetics system, we analyzed the effects of alanine substitutions at many conserved residues within the SSP on viral replication in cell culture and in a guinea

Высокая степень последовательности пластичности некодовой Интергенной области Аренавируса (IGR) позволяет использовать невирусный универсальный синтетик IGR для аттенизации аренавирусов.

НЕЗАВИСИМЫЙ: Геморрагические лихорадки (ГФА) создают серьезные проблемы в области здравоохранения в регионах, где они эндемичны. Озабоченность в связи с патогенными ареновирусами усиливается из-за отсутствия вакцины от арены, лицензируемой УЛХ, и из-за того, что нынешняя антиаренавирусная терапия ограничивается немаркированным использованием ребравирина, который лишь частично эффективен. Недавно мы продемонстрировали, что некодирующий межгенный регион (МКР), присутствующий в каждом сегменте аренвирусного генома, в сегменте S и L (S-IGR и L-IGR, соответственно), играет важную роль в контроле за

Совпадение в аннотации оригинала
UNLABELLED: Hemorrhagic fever arenaviruses (HFAs) pose important public health problems in regions where they are endemic. Concerns about hu … arenavirus lymphocytic choriomeningitis virus (rLCMVs), whose S-IGRs were replaced by the S-IGR of Lassa virus (LASV) or an entirely nonviral S-IGR-like sequence (Ssyn), are viable, indicating that the function of S-IGR tolerates a high degree of sequence plasticity. In addition, rLCMVs whose L-IGRs were replaced by Ssyn or S-IGRs of the very distantly relat …

The C-terminal region of lymphocytic choriomeningitis virus nucleoprotein contains distinct and segregable functional domains involved in NP-Z interaction and counteraction of the type I interferon response.

Several arenaviruses cause hemorrhagic fever (HF) disease in humans that is associated with high morbidity and significant mortality. Arenav … istinct and segregable NP functions. A similar NP-Z interaction was confirmed for the HF arenavirus Lassa virus (LASV). Notably, LCMV NP interacted similarly with both LCMV Z and LASV Z, while LASV NP interacted only with LASV Z. Our results also suggest the presence of a conserved protein domain within NP but with specific amino acid residues playing key rol …

Infectious medical waste (IMW) and disease transmission: A critical public health challenge in Africa and the global implications - A systematic review.

BACKGROUND: Infectious Medical Waste (IMW) from both human and animal healthcare sources have the potential to transmit diseases in human populations due to its pathogenic composition. Conversely, a paucity of data regarding cause-and-effect relationships inhibits our understanding of the extent to which disease transmission occurs. In parts of Africa where the management of IMW is not prioritized, the risks to public health, along with its global implications cannot be ignored. METHODOLOGY: A systematic literature search following the PRISMA guidelines was conducted across five electronic da

Potent inhibition of arenavirus infection by a novel fusion inhibitor.

Several arenaviruses, including Lassa and Lujo viruses in Africa and five New World arenavirus (NWA) species in the Americas, cause life-threatening viral hemorrhagic fevers. In the absence of licensed antiviral therapies, these viruses pose a significant public health risk. The envelope glycoprotein complex (GPC) mediates arenavirus entry through a pH-dependent fusion of the viral and host endosomal membranes. It thus is recognized as a viable target for small-molecule fusion inhibitors. Here, we report on the antiviral activity and pre-clinical development of the novel broad-spectrum arenavi

Comparison of broad-spectrum antiviral activities of the synthetic rocaglate CR-31-B (-) and the eIF4A-inhibitor Silvestrol.

Rocaglates, a class of natural compounds isolated from plants of the genus Aglaia, are potent inhibitors of translation initiation. They are proposed to form stacking interactions with polypurine sequences in the 5'-untranslated region (UTR) of selected mRNAs, thereby clamping the RNA substrate onto eIF4A and causing inhibition of the translation initiation complex. Since virus replication relies on the host translation machinery, it is not surprising that the rocaglate Silvestrol has broad-spectrum antiviral activity. Unfortunately, synthesis of Silvestrol is sophisticated and time-consuming,

A systematic screen of FDA-approved drugs for inhibitors of biological threat agents.

BACKGROUND: The rapid development of effective medical countermeasures against potential biological threat agents is vital. Repurposing existing drugs that may have unanticipated activities as potential countermeasures is one way to meet this important goal, since currently approved drugs already have well-established safety and pharmacokinetic profiles in patients, as well as manufacturing and distribution networks. Therefore, approved drugs could rapidly be made available for a new indication in an emergency. METHODOLOGY/PRINCIPAL FINDINGS: A large systematic effort to determine whether exi