Fatal Human Cases Research Articles

Rabies epidemiology in the central of Tunisia: A Call for a One-Health Approach

Abstract Background Advocating for a One-Health approach is crucial for ensuring effective rabies surveillance in Africa, including Tunisia. Collecting information is essential to evaluate the prevalence of dog bites and rabies in Tunisia. To address this, we conducted an analysis of reported incidents in the central region of Tunisia from 2019 to 2022. This analysis aimed to generate valuable insights that can inform strategies for rabies elimination in Tunisia, highlighting the importance of the One-Health approach. Methods We carried out a descriptive study using surveillance data from Monastir governorate in Central Tunisia. All humans exposed to animals, residents in Monastir Governorate and declared to the regional directorate of primary health care from January 1, 2019 to December 31, 2022 were included in our study. Data were entered, cleaned, and analyzed using Excel. Results During the studied period, 7789 cases of human exposures to animals were reported with an annual average of 1969 ± 207 exposures per year. The annual incidence rate of exposure to animal bites was 324 per 100,000 population. The sex-ratio was 2.07 and almost one third of exposed humans were aged less than 15 years-old. The most listed offending animals were dogs (65.2%), followed by cats (24.4%). The number of exposures by unvaccinated dogs increased significantly during our study period. Post-exposure prophylaxis (PEP) was applied among 99% (n = 7772) of declared exposures. Among them, 2.5% (n = 202) did not complete the PEP recommended protocol. During our study period, rabies was confirmed in 39 animals. Two fatal human rabies cases were declared respectively in 2021 and 2022. Conclusions Rabies remains a worrying health problem in Tunisia with a high percentage reported among youth and males. Targeting children and adolescents by education and information campaigns about preventive measures and mass dog vaccination are the key to ending this scourge. Key messages • It is crucial to reinforce preventive strategies, such as mass dog vaccination programs. • Public awareness about rabies prevention should be enforced in order to decrease Human rabies risks.

Rift Valley fever virus is able to cross the human blood-brain barrier in vitro by direct infection with no deleterious effects.

Rift Valley fever (RVF) is a zoonotic arboviral disease that causes recurrent epidemics in Africa that may trigger fatal neurological disorders. However, the mechanisms of neuroinvasion by which the RVF virus (RVFV) reaches the human central nervous system (CNS) remain poorly characterized. In particular, it is not clear how RVFV is able to cross the human blood-brain barrier (hBBB), which is a neurovascular endothelium that protects the brain by regulating brain and blood exchanges. To explore these mechanisms, we used an in vitro hBBB model to mimic in vivo hBBB selectiveness and apicobasal polarity. Our results highlight the ability of RVFV to cross the hBBB by direct infection in a non-structural protein S (NSs)-independent but strain-dependent manner, leading to astrocyte and pericyte infections. Interestingly, RVFV infection did not induce hBBB disruption and was associated with progressive elimination of infected cells with no impairment of the tight junction protein scaffold and barrier function. Our work also shows that NSs, a well described RVFV virulence factor, limited the establishment of the hBBB-induced innate immune response and subsequent lymphocyte recruitment. These results provide in vitro confirmation of the ability of RVFV to reach human CNS by direct infection of the hBBB without altering its barrier function, and provide new directions to explore human RVFV neurovirulence and neuroinvasion mechanisms.IMPORTANCEThe RVF virus (RVFV) is capable of infecting humans and inducing severe and fatal neurological disorders. Neuropathogenesis and human central nervous system (CNS) invasion mechanisms of RVFV are still unknown, with only historical studies of autopsy data from fatal human cases in the 1980s and exploration studies in rodent models. One of the gaps in understanding RVFV human pathogenesis is how RVFV is able to cross the blood-brain barrier (BBB) in order to reach the human CNS. For the first time, we show that RVFV is able to directly infect cells of the human BBB in vitro to release viral particles into the human CNS, a well-characterized neuroinvasion mechanism of pathogens. Furthermore, we demonstrate strain-dependent variability of this neuroinvasion mechanism, identifying possible viral properties that could be explored to prevent neurological disorders during RVFV outbreaks.

Genomic Characterization of a Dog-Mediated Rabies Outbreak in El Pedregal, Arequipa, Peru.

Rabies, a re-emerging zoonosis with the highest known human case fatality rate, has been largely absent from Peru, except for endemic circulation in the Puno region on the Bolivian border and re-emergence in Arequipa City in 2015, where it has persisted. In 2021, an outbreak occurred in the rapidly expanding city of El Pedregal near Arequipa, followed by more cases in 2022 after nearly a year of epidemiological silence. While currently under control, questions persist regarding the origin of the El Pedregal outbreak and implications for maintaining rabies control in Peru. We sequenced 25 dog rabies virus (RABV) genomes from the El Pedregal outbreak (n=11) and Arequipa City (n=14) from 2021-2023 using Nanopore sequencing in Peru. Historical genomes from Puno (n=4, 2010-2012) and Arequipa (n=5, 2015-2019), were sequenced using an Illumina approach in the UK. In total, 34 RABV genomes were analyzed, including archived and newly obtained samples. The genomes were analyzed phylogenetically to understand the outbreak's context and origins. Phylogenomic analysis identified two genetic clusters in El Pedregal: 2021 cases stemmed from a single introduction unrelated to Arequipa cases, while the 2022 sequence suggested a new introduction from Arequipa rather than persistence. In relation to canine RABV diversity in Latin America, all new sequences belonged to a new minor clade, Cosmopolitan Am5, sharing relatives from Bolivia, Argentina, and Brazil. Genomic insights into the El Pedregal outbreak revealed multiple introductions over a 2-year window. Eco-epidemiological conditions, including migratory worker patterns, suggest human-mediated movement drove introductions. Despite outbreak containment, El Pedregal remains at risk of dog-mediated rabies due to ongoing circulation in Arequipa, Puno, and Bolivia. Human-mediated movement of dogs presents a major risk for rabies re-emergence in Peru, jeopardizing regional dog-mediated rabies control. Additional sequence data is needed for comprehensive phylogenetic analyses.

Evaluating the epizootic and zoonotic threat of an H7N9 low-pathogenicity avian influenza virus (LPAIV) variant associated with enhanced pathogenicity in turkeys.

Between 2013 and 2017, the A/Anhui/1/13-lineage (H7N9) low-pathogenicity avian influenza virus (LPAIV) was epizootic in chickens in China, causing mild disease, with 616 fatal human cases. Despite poultry vaccination, H7N9 has not been eradicated. Previously, we demonstrated increased pathogenesis in turkeys infected with H7N9, correlating with the emergence of the L217Q (L226Q H3 numbering) polymorphism in the haemagglutinin (HA) protein. A Q217-containing virus also arose and is now dominant in China following vaccination. We compared infection and transmission of this Q217-containing 'turkey-adapted' (ty-ad) isolate alongside the H7N9 (L217) wild-type (wt) virus in different poultry species and investigated the zoonotic potential in the ferret model. Both wt and ty-ad viruses demonstrated similar shedding and transmission in turkeys and chickens. However, the ty-ad virus was significantly more pathogenic than the wt virus in turkeys but not in chickens, causing 100 and 33% mortality in turkeys respectively. Expanded tissue tropism was seen for the ty-ad virus in turkeys but not in chickens, yet the viral cell receptor distribution was broadly similar in the visceral organs of both species. The ty-ad virus required exogenous trypsin for in vitro replication yet had increased replication in primary avian cells. Replication was comparable in mammalian cells, and the ty-ad virus replicated successfully in ferrets. The L217Q polymorphism also affected antigenicity. Therefore, H7N9 infection in turkeys can generate novel variants with increased risk through altered pathogenicity and potential HA antigenic escape. These findings emphasize the requirement for enhanced surveillance and understanding of A/Anhui/1/13-lineage viruses and their risk to different species.

Continued evolution of H10N3 influenza virus with adaptive mutations poses an increased threat to mammals

The H10 subtype avian influenza virus (AIV) poses an ongoing threat to both birds and humans. Notably, fatal human cases of H10N3 and H10N8 infections have drawn public attention. In 2022, we isolated two H10N3 viruses (A/chicken/Shandong/0101/2022 and A/chicken/Shandong/0603/2022) from diseased chickens in China. Genome analysis revealed that these viruses were genetically associated with human-origin H10N3 virus, with internal genes originating from local H9N2 viruses. Compared to the H10N8 virus (A/chicken/Jiangxi/102/2013), the H10N3 viruses exhibited enhanced thermostability, increased viral release from erythrocytes, and accumulation of hemagglutinin (HA) protein. Additionally, we evaluated the pathogenicity of both H10N3 and H10N8 viruses in mice. We found that viral titers could be detected in the lungs and nasal turbinates of mice infected with the two H10N3 viruses, whereas H10N8 virus titers were detectable in the lungs and brains of mice. Notably, the proportion of double HA Q222R and G228S mutations in H10N3 viruses has increased since 2019. However, the functional roles of the Q222R and G228S double mutations in the HA gene of H10N3 viruses remain unknown and warrant further investigation. Our study highlights the potential public health risk posed by the H10N3 virus. A spillover event of AIV to humans could be a foretaste of a looming pandemic. Therefore, it is imperative to continuously monitor the evolution of the H10N3 influenza virus to ensure targeted prevention and control measures against influenza outbreaks.

Lessons for the world: Rabies resurgence in rabies free Timor-Leste and the urgent actions needed for prevention measures

Rabies, a fatal viral illness transmitted from animals to humans, remains a globally significant public health concern. Timor-Leste, previously considered rabies-free, reported its first fatal human rabies case in March 2024, signaling a resurgence of the disease. The case involved a 19-year-old female bitten by a dog in December 2023, highlighting gaps in post-exposure prophylaxis (PEP) administration. Subsequent investigations revealed 29 suspected rabies cases, prompting urgent public health responses including dog vaccinations and healthcare worker training. Despite challenges such as limited vaccine availability, comprehensive strategies advocated by the World Health Organization (WHO) offer hope for rabies control. This event underscores the critical need for proactive measures including vaccination programs, public education, surveillance enhancement, and regional cooperation to prevent rabies emergence and safeguard public health in Timor-Leste and beyond.

Human anthrax outbreak and associated factors in the horrific siege of Tigray, Ethiopia

ObjectivesTo investigate the magnitude of the anthrax outbreak and its associated factors during the war and the de facto siege of Tigray, Ethiopia. Design or methodsA case-control study design was applied after an initial descriptive cross-sectional study. Multiple logistic regression was used to identify factors associated with the outbreak. ResultsA total of 339 participants (113 cases and 226 controls) were enrolled with a mean age of 22 ( ± 17) and 35 ( ± 16) years for cases and control groups, respectively. Human anthrax attack and case fatality rates in selected districts of Tigray were estimated at 42.3 per 100,000 population and 5.4%, respectively. Cutaneous anthrax was identified as the most common case of anthrax, accounting for 141/149 total cases (94.6%). Age, consumption of raw meat of diseased animals, sharing of meat, presence of a diseased person among household members, disposal of diseased/dead animals, and contact with products of diseased/dead animals were associated with the outbreak. ConclusionA high rate of human anthrax attacks and fatal cases was recorded during the Tigray defacto blockade, with an epidemic curve. The defacto blockade of Tigray complicated the investigation and management of the outbreak.

Modelling Marburg Virus Disease in Syrian Golden Hamsters: Contrasted Virulence Between Angola and Ci67 Strains.

Marburg virus (MARV) has caused numerous sporadic outbreaks of severe hemorrhagic fever in humans. Human case fatality rates of Marburg virus disease (MVD) outbreaks range from 20% to 90%. Viral genotypes of MARV can differ by over 20%, suggesting variable virulence between lineages may accompany this genetic divergence. Comparison of existing animal models of MVD employing different strains of MARV support differences in virulence across MARV genetic lineages; however, there are few systematic comparisons in models that recapitulate human disease available. We compared features of disease pathogenesis in uniformly lethal hamster models of MVD made possible through serial adaptation in rodents. No further adaptation from a previously reported guinea pig-adapted (GPA) isolate of MARV-Angola was necessary to achieve uniform lethality in hamsters. Three passages of GPA MARV-Ci67 resulted in uniform lethality, where 4 passages of a GPA Ravn virus was 75% lethal. Hamster-adapted MARV-Ci67 demonstrated delayed time to death, protracted weight loss, lower viral burden, and slower histologic alteration compared to GPA MARV-Angola. These data suggest isolate-dependent virulence differences are maintained even after serial adaptation in rodents and may serve to guide choice of variant and model used for development of vaccines or therapeutics for MVD.

Diversification of Bourbon Virus in New York State.

Bourbon virus (BRBV, family Orthomyxoviridae) is a tickborne virus recently detected in the United States (US). BRBV was first identified from a fatal human case in 2014 in Bourbon County, Kansas. Enhanced surveillance in Kansas and Missouri implicated Amblyomma americanum as the primary vector for BRBV. Historically, BRBV was only detected in the lower midwestern US, but since 2020 it has been reported in North Carolina, Virginia, New Jersey, and New York State (NYS). This study aimed to elucidate genetic and phenotypic characteristics of BRBV strains from NYS through whole genome sequencing and the assessment of replication kinetics in mammalian cultures and A. americanum nymphs. Sequence analysis revealed the existence of two divergent BRBV clades circulating in NYS. BRBV NY21-2143 is closely related to the midwestern BRBV strains but has unique substitutions in the glycoprotein. Two other NYS BRBV strains, BRBV NY21-1814 and BRBV NY21-2666, form a distinct clade unique from previously sequenced BRBV strains. Phenotypic diversification was also detected in NYS BRBV strains compared to each other and midwestern BRBV strains, with BRBV NY21-2143 displaying attenuation in rodent-derived cell culture and a fitness advantage in experimentally infected A. americanum. These data suggest genetic and phenotypic diversification of emergent BRBV strains circulating in NYS that could contribute to increased spread of BRBV in the northeastern US.

H10Nx avian influenza viruses detected in wild birds in China pose potential threat to mammals

H10 subtype avian influenza viruses (AIVs) have been isolated from wild and domestic avian species worldwide and have occasionally crossed the species barrier to mammalian hosts. Fatal human cases of H10N8 infections and the recent detection of human H10N3 infections have drawn widespread public attention. In this study, 25 H10Nx viruses were isolated from wild waterfowl in China during a long-term surveillance of AIVs. We conducted phylogenetic and phylogeographic studies of the hemagglutinin (HA) genes of global H10 viruses to determine the spatiotemporal patterns of spread and the roles of different hosts in viral transmission. We found the pattern of AIV transmission from wild birds to poultry to humans, and Anatidae have acted as the seeding population in the spread of the virus. Phylogenetic incongruence indicated complex reassortment events and our isolates were divided into eight genotypes (G1–8). We also found that the HA genes of the G8 viruses belonged to the North American lineage, indicating that intercontinental gene flow has occurred. Their receptor-binding specificity showed that the G1/4/5/6/7/8 viruses bind to both human-type α2,6-linked sialic acid receptors and avian-type α2,3-linked sialic acid receptors. Mouse studies indicated that the H10Nx isolates replicated efficiently in the respiratory system without preadaptation, but showed low pathogenicity in mice. The H10Nx isolates showed no (G2/4/7) or low pathogenicity (G1/3/5/6/8) in chickens, and the G6 and G8 viruses could be transmitted to chickens through direct contact. The asymptomatic shedding of these wild-bird-origin H10Nx isolates in chickens and their good adaptation in mice should increase the ease of their transmission to humans, and they therefore pose a threat to public health. Our findings demonstrate a further understanding of wild bird-origin H10 viruses and provide information for the continuous surveillance of H10 subtype viruses.

Rabies Virus Populations in Humans and Mice Show Minor Inter-Host Variability within Various Central Nervous System Regions and Peripheral Tissues.

Rabies virus (RABV) has a broad host range and infects multiple cell types throughout the infection cycle. Next-generation sequencing (NGS) and minor variant analysis are powerful tools for studying virus populations within specific hosts and tissues, leading to novel insights into the mechanisms of host-switching and key factors for infecting specific cell types. In this study we investigated RABV populations and minor variants in both original (non-passaged) samples and in vitro-passaged isolates of various CNS regions (hippocampus, medulla oblongata and spinal cord) of a fatal human rabies case, and of multiple CNS and non-CNS tissues of experimentally infected mice. No differences in virus populations were detected between the human CNS regions, and only one non-synonymous single nucleotide polymorphism (SNP) was detected in the fifth in vitro passage of virus isolated from the spinal cord. However, the appearance of this SNP shows the importance of sequencing newly passaged virus stocks before further use. Similarly, we did not detect apparent differences in virus populations isolated from different CNS and non-CNS tissues of experimentally infected mice. Sequencing of viruses obtained from pharyngeal swab and salivary gland proved difficult, and we propose methods for improving sampling.

Japanese Encephalitis Virus: The Emergence of Genotype IV in Australia and Its Potential Endemicity.

A fatal case of Japanese encephalitis (JE) occurred in northern Australia in early 2021. Sequence studies showed that the virus belonged to genotype IV (GIV), a genotype previously believed to be restricted to the Indonesian archipelago. This was the first locally acquired case of Japanese encephalitis virus (JEV) GIV to occur outside Indonesia, and the second confirmed fatal human case caused by a GIV virus. A closely related GIV JEV strain subsequently caused a widespread outbreak in eastern Australia in 2022 that was first detected by fetal death and abnormalities in commercial piggeries. Forty-two human cases also occurred with seven fatalities. This has been the first major outbreak of JEV in mainland Australia, and geographically the largest virgin soil outbreak recorded for JEV. This outbreak provides an opportunity to discuss and document the factors involved in the virus' spread and its ecology in a novel ecological milieu in which other flaviviruses, including members of the JE serological complex, also occur. The probable vertebrate hosts and mosquito vectors are discussed with respect to virus spread and its possible endemicity in Australia, and the need to develop a One Health approach to develop improved surveillance methods to rapidly detect future outbreak activity across a large geographical area containing a sparse human population. Understanding the spread of JEV in a novel ecological environment is relevant to the possible threat that JEV may pose in the future to other receptive geographic areas, such as the west coast of the United States, southern Europe or Africa.

P487 Basidiobolus omanensis, an emerging pathogen to watch out for?

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM Introduction Basidiobolus species can be found in amphibian, reptile, lizard, insectivorous bat, and soil, as well as decaying vegetables, and fruits. Basidiobolus species infect both adults and children, with the majority of cases reported from the Middle East, including Oman. Basidiobolomycosis is a chronic subcutaneous infection of the trunk and limbs that typically manifests as subcutaneous or gastrointestinal lesions with only a few cases of systemic involvement. Basidiobolus haptosporus, B. heterosporus, B. magnus, B. meristosporus, B. microsporus, B. omanensis and B. ranarum are the seven species in the genus Basidiobolus. Four of these species have been linked to gastrointestinal infections in humans. Basidiobolus ranarum is the most commonly reported species from humans, followed by B. omanensis. We recently described B. omanensis as a novel species from a patient in Oman. It was isolated from a boy with type 1 diabetes who died as a result of basidiobolmycosis complications. Four more fatal human cases have been documented since then (unpublished data), but little is known about its role as a pathogen in humans.ObjectiveThe goal of this paper is to present four cases of basidiobolomycosis caused by B. omanensis in young children and adults, each with unique diagnostic and treatment challenges.MethodsWe collected four cases of basidiobolomycosis caused by B. omanensis from various tertiary hospitals in Oman. All identifications were based on ribosomal DNA gene sequencing of the internal transcribed spacers (ITS) and partial large subunit (LSU). The CLSI method was used for testing the antifungal drug susceptibility in vitro.ResultsWe present four new cases of Basidiobolus infection in humans (two from children and two from adults). The underlying condition, site of infection, clinical presentation, treatment, and outcomes are all summarized in Table 1. Basidiobolus omanensis strains isolated from these cases were molecularly identified using (ITS and LSU) gene sequencing. The minimum inhibitory concentration (MIC) for amphotericin B (AMB) is 1 µg/ml, isavuconazole (ISC) is 4 µg/ml, itraconazole (ITC), posaconazole (PSC), and voriconazole (VRC) is > 16 µg/ml respectively. These were the first cases of the fungus B. omanensis ever diagnosed globally at various hospitals in Oman. All of the cases presented diagnostic and treatment challenges. Despite the atypical nature of the disease, clinical response was obtained following surgical excision and antifungal treatment, and the mortality rate among the four cases was 50%.ConclusionThis new species may cause problems with identification and antifungal susceptibility, which is why clinicians should be aware of infections with uncommon mould species and consider DNA sequencing for confirmation. Any fungus can cause infection in an immunocompromised host and should never be dismissed as a contaminant out of hand.

Towards an integrated surveillance of zoonotic diseases in Burkina Faso: the case of anthrax

BackgroundAnthrax is a zoonotic disease that causes frequent outbreaks in livestock and fatal human cases in Burkina Faso. Effective surveillance of this disease calls for the establishment of an integrated surveillance system, in line with the One Health concept. However, despite a strong technical and financial support from international partners, surveillance is still poorly conducted within an integrated approach. Based on stakeholder perspectives, the study has for objective to deepen our understanding of the anthrax surveillance system and to identify the obstacles and levers towards a more integrated approach to anthrax surveillance in Burkina Faso.MethodsThe data was collected from a literature review and interviews with surveillance stakeholders. We first conducted a qualitative descriptive analysis of the data to characterize the surveillance system (programmes, actors, collaboration). In a second step, we conducted a thematic analysis of the informants' discourse in order to identify what represents an obstacle or, conversely, a lever for a more integrated approach to anthrax surveillance.ResultsThe surveillance system of anthrax in Burkina Faso includes three programmes (in the livestock, wildlife and human sectors), which involves 30 actors. These sectoral programmes operate almost independently from one another, although some collaborations are existing for the governance and implementation of surveillance activities. Analysis of the discourse of key stakeholders led to the identification of four categories of factors that may influence the implementation of an integrated surveillance system in the country: knowledge; technical, organizational and social capacities; motivation; intersectoral governance.ConclusionsThis study highlights the difficulty of translating One Health governance to the national level and the need to better articulate the visions of all categories of stakeholders. This study also reveals the need to develop specific evaluation systems for integrated policies in order to provide credible evidence of their added value for a better management of zoonotic diseases. Finally, our study underlines the need to act upstream the emergence of zoonoses and allocate more resources to the prevention of zoonoses than to their control.

Antidotal effect of cyclosporine A against α-amanitin toxicity in CD-1 mice, at clinical relevant doses

Amanita phalloides is one of the most toxic mushrooms worldwide, being responsible for the majority of human fatal cases of mushroom intoxications. α-Amanitin, the most deleterious toxin of A. phalloides, inhibits RNA polymerase II (RNAP II), causing hepatic and renal failure. Herein, we used cyclosporine A after it showed potential to displace RNAP II α-amanitin in silico. That potential was not confirmed either by the incorporation of ethynyl-UTP or by the monitoring of fluorescent RNAP II levels. Nevertheless, concomitant incubation of cyclosporine A with α-amanitin, for a short period, provided significant protection against its toxicity in differentiated HepaRG cells. In mice, the concomitant administration of α-amanitin [0.45 mg/kg intraperitoneal (i.p.)] with cyclosporine A (10 mg/kg i.p. plus 2 × 10 mg/kg cyclosporine A i.p. at 8 and 12 h post α-amanitin) resulted in the full survival of α-amanitin-intoxicated mice, up to 30 days after the toxin's administration. Since α-amanitin is a substrate of the organic-anion-transporting polypeptide 1B3 and cyclosporine A inhibits this transporter and is a potent anti-inflammatory agent, we hypothesize that these mechanisms are responsible for the protection observed. These results indicate a potential antidotal effect of cyclosporine A, and its safety profile advocates for its use at an early stage of α-amanitin intoxications.

Development of a point-of-care immunoassay for Ebola Virus Disease through the detection of Ebola virus soluble glycoprotein

Abstract Ebola Virus Disease (EVD) is a deadly infectious disease that is caused by an infection with Ebola virus (EBOV). EVD is one of the deadliest viral diseases with a human case fatality rate of up to 90%. The largest outbreak to date was the 2013–2016 West African outbreak in which Zaire ebolavirus (ZEBOV) was responsible for over 11,000 deaths. Transmission of the virus can occur through contact with an infected animal or human. Early detection is imperative to prevent the spread of disease and reduce the risk of a potential epidemic by isolating known infected patients. The current gold standard for diagnosing EVD is polymerase chain reaction assays which requires complex laboratory equipment and highly trained personnel that is not easily accessible in resource-limited areas. There is a great need for an EBOV rapid diagnostic test that can be implemented at the point-of-care (POC). Multiple lateral flow immunoassays (LFIs) have been developed for this need and have received emergency use authorization. Many of these tests rely on the detection of Ebola virus VP40 antigen, however, soluble glycoprotein (sGP) has the potential to be a better biomarker for EVD rapid detection as it is abundant in the blood during an infection. The goal of this study was to produce an EBOV sGP LFI prototype. A library of seventeen monoclonal antibodies reactive to EBOV sGP were produced and characterized via enzyme-linked immunosorbent assay, surface plasmon resonance, and Western immunoblotting. From this mAb library, LFI prototypes were developed and assessed for the potential use as a rapid POC diagnostic for EVD. Supports by the National Institute of Allergy and Infectious Diseases under grant 1R41AI149940

Japanese encephalitis virus: an emerging and re-emerging virus in Australia

Japanese encephalitis virus (JEV) first emerged in the Torres Strait of north-eastern Australia in 1995, with three human cases, and widespread infection of pigs on a number of islands. The virus was shown to belong to genotype II. Further cases occurred in 1998, including the first case on mainland Australia on Cape York. A second genotype of JEV, genotype Ia, was reported in mosquitoes and pigs in 2000–04, possibly displacing genotype II. JEV re-emerged in Australia with a fatal human case on the Tiwi Islands, Northern Territory, in 2021, and shown to belong to genotype IV. This case was followed about a year later by a large outbreak of JE; first detected in piggeries in four states, Queensland, New South Wales, Victoria, and South Australia, resulting in reproductive losses affecting 80 piggeries and 42 human cases, with seven fatal cases. The wide geographic spread of cases suggested that the virus had been circulating for a number of months or even years prior to detection, and has led to significant concern that the virus will become endemic to Australia, in a similar ecology to Murray Valley encephalitis virus. Known competent mosquito vectors and ardeid birds, as maintenance hosts, occur in Australia, and it is probable that feral pigs will provide an additional wildlife reservoir of virus. Little is known of the properties of genotype IV, but it is expected to have a similar ecology and pathogenesis to other JEV genotypes.

Histologic pulmonary lesions of SARS-CoV-2 in 4 nonhuman primate species: An institutional comparative review.

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an emergent, amphixenotic infection that resulted in a pandemic declaration in March 2020. A rapid search for appropriate animal models of this newly emergent viral respiratory disease focused initially on traditional nonhuman primate research species. Nonhuman primate models have previously been shown to be valuable in evaluation of emerging respiratory coronaviruses with pandemic potential (ie, SARS-CoV and Middle East respiratory syndrome coronavirus). In this article, we review the pulmonary histopathologic characteristics and immunohistochemical evaluation of experimental SARS-CoV-2 infection in the rhesus macaque, pigtail macaque, African green monkey, and squirrel monkey. Our results indicate that all evaluated nonhuman primate species developed variably severe histopathologic changes typical of coronavirus respiratory disease characterized by interstitial pneumonia with or without syncytial cell formation, alveolar fibrin, and pulmonary edema that progressed to type II pneumocyte hyperplasia. Lesion distribution was multifocal, frequently subpleural, and often more severe in lower lung lobes. However, squirrel monkeys showed the least severe and least consistent lesions of the evaluated nonhuman primates. Additionally, our results highlight the disparate physical relationship between viral antigen and foci of pulmonary lesions. While classic respiratory coronaviral lesions were observed in the lungs of all nonhuman primates evaluated, none of the primates exhibited severe lesions or evidence of diffuse alveolar damage and therefore are unlikely to represent the severe form of SARS-CoV-2 infection observed in fatal human cases.

Incursion of European Bat Lyssavirus 1 (EBLV-1) in Serotine Bats in the United Kingdom

Lyssaviruses are an important genus of zoonotic viruses which cause the disease rabies. The United Kingdom is free of classical rabies (RABV). However, bat rabies due to European bat lyssavirus 2 (EBLV-2), has been detected in Daubenton’s bats (Myotis daubentonii) in Great Britain since 1996, including a fatal human case in Scotland in 2002. Across Europe, European bat lyssavirus 1 (EBLV-1) is commonly associated with serotine bats (Eptesicus serotinus). Despite the presence of serotine bats across large parts of southern England, EBLV-1 had not previously been detected in this population. However, in 2018, EBLV-1 was detected through passive surveillance in a serotine bat from Dorset, England, using a combination of fluorescent antibody test, reverse transcription-PCR, Sanger sequencing and immunohistochemical analysis. Subsequent EBLV-1 positive serotine bats have been identified in South West England, again through passive surveillance, during 2018, 2019 and 2020. Here, we confirm details of seven cases of EBLV-1 and present similarities in genetic sequence indicating that emergence of EBLV-1 is likely to be recent, potentially associated with the natural movement of bats from the near continent

Case Fatality as an Indicator for the Human Toxicity of Pesticides—A Systematic Scoping Review on the Availability and Variability of Severity Indicators of Pesticide Poisoning

Objective: To investigate if case fatality and other indicators of the severity of human pesticide poisonings can be used to prioritize pesticides of public health concern. To study the heterogeneity of data across countries, cause of poisonings, and treatment facilities. Methods: We searched literature databases as well as the internet for studies on case-fatality and severity scores of pesticide poisoning. Studies published between 1990 and 2014 providing information on active ingredients in pesticides or chemical groups of active ingredients were included. The variability of case-fatality-ratios was analyzed by computing the coefficient of variation as the ratio of the standard deviation to the mean. Findings: A total of 149 papers were identified of which 67 could be included after assessment. Case-fatality-ratio (CFR) on 66 active ingredients and additionally on 13 groups of active ingredients were reported from 20 countries. The overall median CFR for group of pesticides was 9%, for single pesticides 8%. Of those 12 active ingredients with a CFR above 20% more than half are WHO-classified as “moderately hazardous” or “unlikely to present acute hazard”. Two of seven pesticides considered “unlikely to present hazard in normal use” showed a CFR above 20%. The cross-study variability of reported case fatality was rather low. Studies most often utilized the Glasgow Coma Score for grading the severity of poisoning. Conclusion: Although human pesticide poisoning is a serious public health problem, an unexpectedly small number of publications report on the clinical outcomes within our study period. However, CFRs of acute human pesticide poisoning are available for several groups of pesticides as well as for active ingredients showing moderate cross-study variability. Our results underline that CFR is an indicator of the human toxicity of pesticides and can be utilized to prioritize highly hazardous pesticides especially since there is limited correspondence between the animal-test-based hazard classification and the human CFR of the respective pesticide. The reporting of available poisoning data should be improved, human case-fatality data are a reasonable tool to be included systematically in the periodic statutory review of pesticides and their regulation.