Hantavirus infection: a global zoonotic challenge

Asymmetric association between meteorological factors and human infections with hemorrhagic fever with renal syndrome: A 16-year ecological trend study in Shaanxi, China

Objective

Hemorrhagic fever with renal syndrome (HFRS) continues to pose a significant threat to global health. This study aimed to investigate both the long- and short-term asymmetric impacts of variations in meteorological variables on HFRS.

Methods

The reported monthly HFRS incidence data from Shaanxi between 2004 and 2019, along with corresponding meteorological data, were collected to conduct an ecological trend analysis. Subsequently, the autoregressive distributed lag (ARDL) and nonlinear ARDL (NARDL) models were used to examine the long- and short-term asymmetric effects of climate variables on HFRS incidence.

Results

Overall, a reduction in HFRS incidence was observed in Shaanxi from 2004 to 2019, with an average annual percentage change of -0.498 % (95 %CI -13.247 % to 12.602 %). HFRS incidence peaked in December and reached its lowest point in March each year. A 1 mm increase in aggregate precipitation (AP) was associated with a 4.3 % rise in HFRS incidence, while a 1 mm decrease contributed to a 3.7 % increase, indicating a long-term asymmetric impact (Wald long-term asymmetry test [WLT] = 9.072, P = 0.003). In the short term, a 1 % decrease in mean relative humidity (MRH) led to a 5.7 % decline in HFRS incidence (Wald short-term asymmetry test [WSR] = 5.978, P = 0.015). Additionally, changes in meteorological variables showed varied effects: ΔMWV(+) at a 1-month lag had a significant positive short-term effect on HFRS; ΔMRH(+) at a 3-month lag, ΔAP(+) at a 2-month lag, ΔAP(-) at a 1-month lag, ΔASH(+) at a 1-month lag, and ΔASH(-) at a 3-month lag all exhibited strong negative short-term impacts on HFRS incidence.

Conclusions

Weather variability plays a significant role in influencing HFRS incidence, with both long- and short-term asymmetric and/or symmetric effects. Utilizing the NARDL model through a One Health lens offers promising opportunities for enhancing HFRS control measures.

Spatiotemporal distribution and meteorological factors of hemorrhagic fever with renal syndrome in Hubei province

BACKGROUND

Hemorrhagic fever with renal syndrome (HFRS) is a vital rodent-borne disease, and poses a serious public health threat in Hubei province. We aimed to explore the spatiotemporal distribution of HFRS in Hubei province during 2005-2022, and the effects of meteorological factors.

METHODS

Data on HFRS cases at the county level in Hubei province during 2005-2022 were obtained from the Chinese Center for Disease Prevention and Control Information System. The monthly meteorological data at the city level was extracted from the China Meteorological Data Sharing Service System from 2016 to 2020. Descriptive analyses, joinpoint regression model, spatial correlation analyses, Geodetector model and autoregressive integrated moving average (ARIMA) model were conducted to investigate the epidemic characteristics, temporal trend, spatial distribution, influencing factors of HFRS and predict its trend.

RESULTS

A total of 6,295 cases were reported in Hubei province during 2005-2022, with an average incidence of 6/1,000,000. Most cases were males (74.52%) and aged 40-69 years (71.87%). The monthly HFRS cases showed two seasonal peaks, which were summer (May to June) and winter (November to December). The HFRS incidence remained fluctuating at a low level during 2005-2015, followed an increasing trend during 2015-2018, and then decreased during 2018-2022. Hotspots were concentrated in the center of Hubei province in all 3 periods, including Qianjiang, Tianmen and some counties from Xiangyang, Jingmen and Jingzhou cities. The distribution of HFRS had a positive association with wind speed, while a "V"-shaped correlation with mean temperature, with an explanatory power of 3.21% and 1.03% respectively (both P <0.05). The ARIMA model predicted about 1,223 cases occurred in the next 3 years.

CONCLUSIONS

HFRS cases showed seasonal fluctuation and spatial clustering in Hubei province. Central plain areas showed high risk of HFRS. Wind speed and mean temperature had significant effects on the transmission of HFRS in Hubei province. The results alert health authorities to conduct disease-climate surveillance and comprehensive prevention strategies, especially in high-risk counties.

A comprehensive investigation of Glycoprotein-based nucleic acid vaccines for Hantaan Virus

Hemorrhagic fever with renal syndrome (HFRS) occurs throughout Eurasia with considerable morbidity and mortality. Currently, the absence of specific treatments or effective antiviral drugs for hantavirus infection makes developing safe and effective vaccines a high priority. Here, we report the development of three novel nucleic acid vaccine candidates, mRNA, naked DNA, and DNA encapsulated in lipid nanoparticles, encoding the glycoproteins of the Hantaan virus (HTNV). To comprehensively evaluate the potential of candidate HTNV nucleic acid vaccines in preventing HFRS, we focus on evaluating their immunogenicity and efficacy in mice and comparing them with an inactivated vaccine as the benchmark. Our findings reveal that all candidate vaccines activated instant and sustained immune responses, offering comparable in vivo protective efficacy to the inactivated vaccines. Notably, compared to the inactivated vaccine, mRNA vaccine induced stronger virus-specific T-helper 1 cell immune response, while DNA-LNP elicited higher levels of neutralizing antibodies in mice. These results mark a significant step in developing nucleic acid vaccines for HTNV, suggesting that sequential immunization with DNA and mRNA vaccines could further amplify the advantages of nucleic acid vaccines.

Coinfection with Orthohantavirus and Leptospira spp. in Rats Collected from Markets in Indonesia

Background: Rats are an important reservoir animal for several zoonotic pathogens worldwide, including hantaviruses and Leptospira spp., which are the causative agents of hemorrhagic fever with renal syndrome, hantavirus cardiopulmonary syndrome, and leptospirosis. Although a previous study indicated a high frequency of antihantaviral antibodies in patients with acute fever in Indonesia, circulating hantaviruses and their reservoir animals in the country remain limited. Materials and Methods: The presence of hantavirus in rats captured in the urban area of Bogor, Indonesia, from which Leptospira spp. were isolated using PCR, followed by DNA sequencing. Immunohistochemical analyses were performed to detect hantaviral and leptospiral antigens in rat kidney tissues. Results: Seoul of Orthohantavirus seoulense (SEOV) RNA was detected from 24 of 80 Rattus norvegicus (30%). SEOV and Leptospira coinfection was detected in 10 of 80 rats (12.5%). Immunohistochemistry revealed that hantavirus antigens were positively stained in the interstitial capillaries and cells, whereas Leptospira antigens were stained in the luminal side of the renal tubules. Conclusion: This study revealed a high prevalence of SEOV and SEOV and Leptospira coinfection among rats in the urban areas of Bogor, Indonesia, indicating a potential risk of rat-borne zoonotic diseases in the area.

Transcriptomic analysis reveals key molecular signatures across recovery phases of hemorrhagic fever with renal syndrome

BACKGROUND

Hemorrhagic fever with renal syndrome (HFRS), a life-threatening zoonosis caused by hantavirus, poses significant mortality risks and lacks specific treatments. This study aimed to delineate the transcriptomic alterations during the recovery phases of HFRS.

METHODS

RNA sequencing was employed to analyze the transcriptomic alterations in peripheral blood mononuclear cells from HFRS patients across the oliguric phase (OP), diuretic phase (DP), and convalescent phase (CP). Twelve differentially expressed genes (DEGs) were validated using quantitative real-time PCR in larger sample sets.

RESULTS

Our analysis revealed pronounced transcriptomic differences between DP and OP, with 38 DEGs showing consistent expression changes across all three phases. Notably, immune checkpoint genes like CD83 and NR4A1 demonstrated a monotonic increase, in contrast to a monotonic decrease observed in antiviral and immunomodulatory genes, including IFI27 and RNASE2. Furthermore, this research elucidates a sustained attenuation of immune responses across three phases, alongside an upregulation of pathways related to tissue repair and regeneration.

CONCLUSION

Our research reveals the transcriptomic shifts during the recovery phases of HFRS, illuminating key genes and pathways that may serve as biomarkers for disease progression and recovery.

25-Hydroxycholesterol inhibits Hantavirus infection by reprogramming cholesterol metabolism

Hantavirus causes two types of acute diseases: hemorrhagic fever with renal syndrome and hantavirus pulmonary syndrome. It is a major health concern due to its high mortality and lack of effective treatment. Type I interferon treatment has been suggested to be effective against hantavirus when treated in advance. Interferons induce multiple interferon-stimulated genes (ISGs), whose products are highly effective at resisting and controlling viruses. A product of ISGs, the enzyme cholesterol 25-hydroxylase (CH25H), catalyzes the oxidation of cholesterol to 25-hydroxycholesterol (25HC). 25HC can inhibit multiple enveloped-virus infections, but the mechanism is largely unknown, and whether 25HC plays an important role in regulating hantavirus remains unexplored. In this study, we show that Hantaan virus (HTNV), the prototype hantavirus, induced CH25H gene in infected cells. Overexpression of CH25H and treatment with 25HC, inhibited HTNV infection, possibly by lowering 3-hydroxy-3-methyl-glutaryl coenzyme A reductase (HMG-CoA reductase, HMGCR), which inhibits cholesterol biosynthesis. In addition, cholesterol-lowering drugs such as HMGCR-targeting statins have potent hantavirus inhibitory effects. Our results indicate that 25HC and some statins are potential antiviral agents effective against hantavirus infections. This study provides evidence that targeting cholesterol metabolism is promising in developing specific hantavirus antivirals and indicates the possibility of repurposing FDA-approved cholesterol-lowering drug, statins for treating hantavirus infection.

Distribution and genetic characterization of hantaviruses in bats and rodents from Yunnan

Hemorrhagic fever with renal syndrome caused by hantaviruses has long been a serious public health issue in Yunnan Province. Hantaviruses exhibit a high extent of biodiversity in their natural hosts, particularly in mammalian hosts. This study was conducted to screen for hantaviruses in bats and rodents in Yunnan Province and elucidate their genetic characteristics and possible zoonotic disease risk. Hantaviruses were detected in 202 bats and 372 rodents with the positive rates 27.49% and 1.25% respectively. A novel lineage (named Lineage 10) of the Seoul virus (SEOV) from rodents and the geographic clustering of hantavirus in bats were identified using phylogenetic analyses of the full-length M- and S-segments. Our study suggest a high cross-species transmissibility of hantaviruses in bats and existence of a new lineage of SEOV in rodents differing significantly from other SEOVs. These results provide data to support the prevention and control of hantavirus-associated diseases in Yunnan Province.

Guanylate-binding protein 1 inhibits Hantaan virus infection by restricting virus entry

Hantaan virus (HTNV) infection can cause hemorrhagic fever with renal syndrome (HFRS) in humans, and currently, there are no long-standing protective vaccines or specific antivirals available. Guanylate-binding protein 1 (GBP1) is an interferon-stimulated gene that defends against various pathogen infections. However, the function of GBP1 in HTNV infection remains unknown. Here, we describe how GBP1 prevents HTNV infection by obstructing virus entry. We found that HTNV infection induced GBP1 expression and that overexpression of GBP1 inhibited HTNV infection, while knockout of GBP1 had the opposite effect. Interestingly, GBP1 did not affect interferon (IFN) signaling during HTNV infection. Instead, GBP1 prevented HTNV from entering cells through clathrin-mediated endocytosis (CME). We also discovered that GBP1 specifically interacted with actin but not dynamin 2 (DNM2) and made it difficult for DNM2 to be recruited by actin, which may account for the suppression of CME during HTNV infection. These findings establish an antiviral role for GBP1 in inhibiting HTNV infection and help us better understand how GBP1 regulates HTNV entry and could potentially aid in developing treatments for this virus.

Spatial-temporal drivers and incidence heterogeneity of hemorrhagic fever with renal syndrome transmission in Shandong Province, China, 2016-2022

BACKGROUND

Hemorrhagic fever with renal syndrome (HFRS) signals a recurring risk in Eurasia in recent years owing to its continued rise in case notifications and the extension of geographical distribution. This study was undertaken to investigate the spatiotemporal drivers and incidence heterogeneity of HFRS transmission in Shandong Province.

METHODS

The epidemiological data for HFRS, meteorological data and socioeconomic data were obtained from China Information System for Disease Control and Prevention, China Meteorological Data Sharing Service System, and Shandong Statistical Yearbook, respectively. The spatial-temporal multicomponent model was employed to analyze the values of spatial-temporal components and the heterogeneity of HFRS transmission across distinct regions.

RESULTS

The total effect values of the autoregressive, epidemic, and endemic components were 0.451, 0.187, and 0.033, respectively, exhibiting significant heterogeneity across various cities. This suggested a pivotal role of the autoregressive component in propelling HFRS transmission in Shandong Province. The epidemic component of Qingdao, Weifang, Yantai, Weihai, and Jining declined sharply at the onset of 2020. The random effect identified distinct incidence levels associated with Qingdao and Weifang, signifying regional variations in HFRS occurrence.

CONCLUSIONS

The autoregressive component emerged as a significant driver in the transmission of HFRS in Shandong Province. Targeted preventive measures should be strategically implemented across various regions, taking into account the predominant component influencing the epidemic.

Epidemiological and clinical characteristics of death from hemorrhagic fever with renal syndrome: a meta-analysis

Introduction

Hemorrhagic fever with renal syndrome (HFRS) is an acute infectious disease comprising five stages: fever, hypotension, oliguria, diuresis (polyuria), and convalescence. Increased vascular permeability, coagulopathy, and renal injury are typical clinical features of HFRS, which has a case fatality rate of 1-15%. Despite this, a comprehensive meta-analyses of the clinical characteristics of patients who died from HFRS is lacking.

Methods

Eleven Chinese- and English-language research databases were searched, including the China National Knowledge Infrastructure Database, Wanfang Database, SinoMed, VIP Database, PubMed, Embase, Scopus, Cochrane Library, Web of Science, Proquest, and Ovid, up to October 5, 2023. The search focused on clinical features of patients who died from HFRS. The extracted data were analyzed using STATA 14.0.

Results

A total of 37 articles on 140,295 patients with laboratory-confirmed HFRS were included. Categorizing patients into those who died and those who survived, it was found that patients who died were older and more likely to smoke, have hypertension, and have diabetes. Significant differences were also observed in the clinical manifestations of multiple organ dysfunction syndrome, shock, occurrence of overlapping disease courses, cerebral edema, cerebral hemorrhage, toxic encephalopathy, convulsions, arrhythmias, heart failure, dyspnea, acute respiratory distress syndrome, pulmonary infection, liver damage, gastrointestinal bleeding, acute kidney injury, and urine protein levels. Compared to patients who survived, those who died were more likely to demonstrate elevated leukocyte count; decreased platelet count; increased lactate dehydrogenase, alanine aminotransferase, and aspartate aminotransferase levels; prolonged activated partial thromboplastin time and prothrombin time; and low albumin and chloride levels and were more likely to use continuous renal therapy. Interestingly, patients who died received less dialysis and had shorter average length of hospital stay than those who survived.

Conclusion

Older patients and those with histories of smoking, hypertension, diabetes, central nervous system damage, heart damage, liver damage, kidney damage, or multiorgan dysfunction were at a high risk of death. The results can be used to assess patients' clinical presentations and assist with prognostication.Systematic review registration:https://www.crd.york.ac.uk/prospero/, (CRD42023454553).

Single dose recombinant VSV based vaccine elicits robust and durable neutralizing antibody against Hantaan virus

Hantaan virus (HTNV) is a pathogenic orthohantavirus prevalent in East Asia that is known to cause hemorrhagic fever with severe renal syndrome (HFRS), which has a high fatality rate. However, a Food and Drug Administration (FDA)-approved vaccine is not currently available against this virus. Although inactivated vaccines have been certified and used in endemic regions for decades, the neutralizing antibody (NAb) titer induced by inactivated vaccines is low and the immunization schedule is complicated, requiring at least three injections spanning approximately 6 months to 1 year. Replication-competent vesicular stomatitis virus (VSV)-based vaccines provide prolonged protection after a single injection. In this study, we successfully engineered the HTNV glycoprotein (GP) in the VSV genome by replacing the VSV-G open reading frame. The resulting recombinant (r) rVSV-HTNV-GP was rescued, and the immunogenicity of GP was similar to that of HTNV. BALB/c mice immunized with rVSV-HTNV-GP showed a high titer of NAb against HTNV after a single injection. Notably, the cross-reactive NAb response induced by rVSV-HTNV-GP against Seoul virus (an orthohantavirus) was higher than that induced by three sequential injections of inactivated vaccines. Upon challenge with HTNV, rVSV-HTNV-GP-immunized mice showed a profoundly reduced viral burden in multiple tissues, and inflammation in the lungs and liver was nearly undetectable. Moreover, a single injection of rVSV-HTNV-GP established a prolonged immunological memory status as the NAbs were sustained for over 1 year and provided long-term protection against HTNV infection. The findings of our study can support further development of an rVSV-HTNV-GP-based HTNV vaccine with a simplified immunization schedule.

Spatiotemporal trends of hemorrhagic fever with renal syndrome (HFRS) in China under climate variation

Hemorrhagic fever with renal syndrome (HFRS) is a zoonotic disease caused by the rodent-transmitted orthohantaviruses (HVs), with China possessing the most cases globally. The virus hosts in China are Apodemus agrarius and Rattus norvegicus, and the disease spread is strongly influenced by global climate dynamics. To assess and predict the spatiotemporal trends of HFRS from 2005 to 2098, we collected historical HFRS data in mainland China (2005-2020), historical and projected climate and population data (2005-2098), and spatial variables including biotic, environmental, topographical, and socioeconomic. Spatiotemporal predictions and mapping were conducted under 27 scenarios incorporating multiple integrated representative concentration pathway models and population scenarios. We identify the type of magistral HVs host species as the best spatial division, including four region categories. Seven extreme climate indices associated with temperature and precipitation have been pinpointed as key factors affecting the trends of HFRS. Our predictions indicate that annual HFRS cases will increase significantly in 62 of 356 cities in mainland China. Rattus regions are predicted to be the most active, surpassing Apodemus and Mixed regions. Eighty cities are identified as at severe risk level for HFRS, each with over 50 reported cases annually, including 22 new cities primarily located in East China and Rattus regions after 2020, while 6 others develop new risk. Our results suggest that the risk of HFRS will remain high through the end of this century, with Rattus norvegicus being the most active host, and that extreme climate indices are significant risk factors. Our findings can inform evidence-based policymaking regarding future risk of HFRS.

Distribution and prevalence of Sin Nombre hantavirus in rodent species in eastern New Mexico

Orthohantaviruses are diverse zoonotic RNA viruses. Small mammals, such as mice and rats are common chronic, asymptomatic hosts that transmit the virus through their feces and urine. In North America, hantavirus infection primarily causes hantavirus cardiopulmonary syndrome (HCPS), which has a mortality rate of nearly 36%. In the United States of America, New Mexico (NM) is leading the nation in the number of HCPS-reported cases (N = 129). However, no reported cases of HCPS have occurred within eastern NM. In this study, we assessed the prevalence of Sin Nombre virus (SNV) in rodent assemblages across eastern NM, using RT-qPCR. We screened for potential rodent hosts in the region, as well as identified areas that may pose significant infection risk to humans. We captured and collected blood and lung tissues from 738 rodents belonging to 23 species. 167 individuals from 16 different species were positive for SNV RNA by RT-qPCR, including 6 species unreported in the literature: Onychomys leucogaster (Northern grasshopper mouse), Dipodomys merriami (Merriam's kangaroo rat), Dipodomys ordii (Ord's kangaroo rat), Dipodomys spectabilis (Banner-tailed kangaroo rat), Perognathus flavus (Silky pocket mouse), and Chaetodipus hispidus (Hispid pocket mouse). The infection rates did not differ between sexes or rodent families (i.e., Cricetidae vs. Heteromyidae). Generalized linear model showed that disturbed habitat types positively influenced the prevalence of SNV at sites of survey. Overall, the results of this study indicate that many rodent species in east New Mexico have the potential to maintain SNV in the environment, but further research is needed to assess species specific infectivity mechanisms and potential risk to humans.

Safety and Immunogenicity of an Andes Virus DNA Vaccine by Needle-Free Injection: A Randomized, Controlled Phase 1 Study

BACKGROUND

Andes virus (ANDV), a rodent-borne hantavirus, causes hantavirus pulmonary syndrome (HPS). The safety and immunogenicity of a novel ANDV DNA vaccine was evaluated.

METHODS

Phase 1, double-blind, dose-escalation trial randomly assigned 48 healthy adults to placebo or ANDV DNA vaccine delivered via needle-free jet injection. Cohorts 1 and 2 received 2 mg of DNA or placebo in a 3-dose (days 1, 29, 169) or 4-dose (days 1, 29, 57, 169) schedule, respectively. Cohorts 3 and 4 received 4 mg of DNA or placebo in the 3-dose and 4-dose schedule, respectively. Subjects were monitored for safety and neutralizing antibodies by pseudovirion neutralization assay (PsVNA50) and plaque reduction neutralization test (PRNT50).

RESULTS

While 98% and 65% of subjects had at least 1 local or systemic solicited adverse event (AE), respectively, most AEs were mild or moderate; no related serious AEs were detected. Cohorts 2, 3, and 4 had higher seroconversion rates than cohort 1 and seropositivity of at least 80% by day 197, sustained through day 337. PsVNA50 geometric mean titers were highest for cohort 4 on and after day 197.

CONCLUSIONS

This first-in-human candidate HPS vaccine trial demonstrated that an ANDV DNA vaccine was safe and induced a robust, durable immune response. Clinical Trials Registration. NCT03682107.

Disparate macrophage responses are linked to infection outcome of Hantan virus in humans or rodents

Hantaan virus (HTNV) is asymptomatically carried by rodents, yet causes lethal hemorrhagic fever with renal syndrome in humans, the underlying mechanisms of which remain to be elucidated. Here, we show that differential macrophage responses may determine disparate infection outcomes. In mice, late-phase inactivation of inflammatory macrophage prevents cytokine storm syndrome that usually occurs in HTNV-infected patients. This is attained by elaborate crosstalk between Notch and NF-κB pathways. Mechanistically, Notch receptors activated by HTNV enhance NF-κB signaling by recruiting IKKβ and p65, promoting inflammatory macrophage polarization in both species. However, in mice rather than humans, Notch-mediated inflammation is timely restrained by a series of murine-specific long noncoding RNAs transcribed by the Notch pathway in a negative feedback manner. Among them, the lnc-ip65 detaches p65 from the Notch receptor and inhibits p65 phosphorylation, rewiring macrophages from the pro-inflammation to the pro-resolution phenotype. Genetic ablation of lnc-ip65 leads to destructive HTNV infection in mice. Thus, our findings reveal an immune-braking function of murine noncoding RNAs, offering a special therapeutic strategy for HTNV infection.

Medically Significant Vector-Borne Viral Diseases in Iran

Vector-borne viral diseases (VBVDs) continue to pose a considerable public health risk to animals and humans globally. Vectors have integral roles in autochthonous circulation and dissemination of VBVDs worldwide. The interplay of agricultural activities, population expansion, urbanization, host/pathogen evolution, and climate change, all contribute to the continual flux in shaping the epidemiology of VBVDs. In recent decades, VBVDs, once endemic to particular countries, have expanded into new regions such as Iran and its neighbors, increasing the risk of outbreaks and other public health concerns. Both Iran and its neighboring countries are known to host a number of VBVDs that are endemic to these countries or newly circulating. The proximity of Iran to countries hosting regional diseases, along with increased global socioeconomic activities, e.g., international trade and travel, potentially increases the risk for introduction of new VBVDs into Iran. In this review, we examined the epidemiology of numerous VBVDs circulating in Iran, such as Chikungunya virus, Dengue virus, Sindbis virus, West Nile virus, Crimean-Congo hemorrhagic fever virus, Sandfly-borne phleboviruses, and Hantavirus, in relation to their vectors, specifically mosquitoes, ticks, sandflies, and rodents. In addition, we discussed the interplay of factors, e.g., urbanization and climate change on VBVD dissemination patterns and the consequent public health risks in Iran, highlighting the importance of a One Health approach to further surveil and to evolve mitigation strategies.

Case Report: Hemorrhagic Fever with Renal Syndrome Complicated by Bilateral Subdural Hematoma

Hemorrhagic fever with renal syndrome (HFRS) is an acute, natural focal disease worldwide. Bilateral subdural hematoma (BSH) is a rare occurrence in patients with HFRS. A 51-year-old man was admitted with fever, headache, lower back pain, and reduced urine volume. The patient was diagnosed with HFRS accompanied by BSH, as evidenced by IgM and IgG antibodies for hantavirus that were positive, and abnormal blood test results and computed tomographic head scan. He recovered and was discharged after symptomatic treatment. Hemorrhagic fever with renal syndrome might present rare clinical manifestations with BSH. The early identification of this condition is crucial to an improved prognosis.

Hantavirus: an overview and advancements in therapeutic approaches for infection

Hantaviruses are a significant and emerging global public health threat, impacting more than 200,000 individuals worldwide each year. The single-stranded RNA viruses belong to the Hantaviridae family and are responsible for causing two acute febrile diseases in humans: Hantavirus pulmonary syndrome (HPS) and hemorrhagic fever with renal syndrome (HFRS). Currently, there are no licensed treatments or vaccines available globally for HTNV infection. Various candidate drugs have shown efficacy in increasing survival rates during the early stages of HTNV infection. Some of these drugs include lactoferrin, ribavirin, ETAR, favipiravir and vandetanib. Immunotherapy utilizing neutralizing antibodies (NAbs) generated from Hantavirus convalescent patients show efficacy against HTNV. Monoclonal antibodies such as MIB22 and JL16 have demonstrated effectiveness in protecting against HTNV infection. The development of vaccines and antivirals, used independently and/or in combination, is critical for elucidating hantaviral infections and the impact on public health. RNA interference (RNAi) arised as an emerging antiviral therapy, is a highly specific degrades RNA, with post-transcriptional mechanism using eukaryotic cells platform. That has demonstrated efficacy against a wide range of viruses, both in vitro and in vivo. Recent antiviral methods involve using small interfering RNA (siRNA) and other, immune-based therapies to target specific gene segments (S, M, or L) of the Hantavirus. This therapeutic approach enhances viral RNA clearance through the RNA interference process in Vero E6 cells or human lung microvascular endothelial cells. However, the use of siRNAs faces challenges due to their low biological stability and limited in vivo targeting ability. Despite their successful inhibition of Hantavirus replication in host cells, their antiviral efficacy may be hindered. In the current review, we focus on advances in therapeutic strategies, as antiviral medications, immune-based therapies and vaccine candidates aimed at enhancing the body's ability to control the progression of Hantavirus infections, with the potential to reduce the risk of severe disease.

Praemonitus praemunitus: can we forecast and prepare for future viral disease outbreaks?

Understanding the origins of past and present viral epidemics is critical in preparing for future outbreaks. Many viruses, including SARS-CoV-2, have led to significant consequences not only due to their virulence, but also because we were unprepared for their emergence. We need to learn from large amounts of data accumulated from well-studied, past pandemics and employ modern informatics and therapeutic development technologies to forecast future pandemics and help minimize their potential impacts. While acknowledging the complexity and difficulties associated with establishing reliable outbreak predictions, herein we provide a perspective on the regions of the world that are most likely to be impacted by future outbreaks. We specifically focus on viruses with epidemic potential, namely SARS-CoV-2, MERS-CoV, DENV, ZIKV, MAYV, LASV, noroviruses, influenza, Nipah virus, hantaviruses, Oropouche virus, MARV, and Ebola virus, which all require attention from both the public and scientific community to avoid societal catastrophes like COVID-19. Based on our literature review, data analysis, and outbreak simulations, we posit that these future viral epidemics are unavoidable, but that their societal impacts can be minimized by strategic investment into basic virology research, epidemiological studies of neglected viral diseases, and antiviral drug discovery.

Investigation of a subunit protein vaccine for HFRS based on a consensus sequence between envelope glycoproteins of HTNV and SEOV

Due to the global resurgence of hemorrhagic fever with renal syndrome (HFRS), more attention is being focused on this dangerous illness. In China and Korea, the only vaccines available are the virus-inactivated vaccine against Hantaan virus (HTNV) or Seoul virus (SEOV), but their efficacy and safety are inadequate. Therefore, it is important to develop new vaccines that are safer and more efficient to neutralize and regulate areas with a high prevalence of HFRS. We employed bioinformatics methods to design a recombinant protein vaccine based on conserved regions of protein consensus sequences in HTNV and SEOV membranes. The S2 Drosophila expression system was utilized to enhance protein expression, solubility and immunogenicity. After the Gn and Gc proteins of HTNV and SEOV were successfully expressed, mice were immunized, and the humoral immunity, cellular immunity, and in vivo protection of the HFRS universal subunit vaccine were systematically evaluated in mouse models. These results indicated that the HFRS subunit vaccine generated elevated levels of binding and neutralizing antibodies, particularly IgG1, compared to that of the traditional inactivated HFRS vaccine. Additionally, the spleen cells of immunized mice secreted IFN-r and IL-4 cytokines effectively. Moreover, the HTNV-Gc protein vaccine successfully protected suckling mice from HTNV infection and stimulated GC responses. In this research, a new scientific approach is investigated to develop a universal HFRS subunit protein vaccine that is capable of producing effective humoral and cellular immunity in mice. The results suggest that this vaccine could be a promising candidate for preventing HFRS in humans.

STING strengthens host anti-hantaviral immunity through an interferon-independent pathway

Hantaan virus (HTNV), the prototype virus of hantavirus, could escape innate immunity by restraining type I interferon (IFN) responses. It is largely unknown whether there existed other efficient anti-hantaviral tactics in host cells. Here, we demonstrate that the stimulator of interferon genes (STING) strengthens the host IFN-independent anti-hantaviral immunity. HTNV infection activates RIG-I through IRE1-XBP 1-mediated ER stress, which further facilitates the subcellular translocation and activation of STING. During this process, STING triggers cellular autophagy by interacting with Rab7A, thus restricting viral replication. To note, the anti-hantaviral effects of STING are independent of canonical IFN signaling. Additionally, neither application of the pharmacological antagonist nor the agonist targeting STING could improve the outcomes of nude mice post HTNV challenge in vivo. However, the administration of plasmids exogenously expressing the mutant C-terminal tail (ΔCTT) STING, which would not trigger the type I IFN responses, protected the nude mice from lethal HTNV infection. In summary, our research revealed a novel antiviral pathway through the RIG-I-STING-autophagy pathway, which offered novel therapeutic strategies against hantavirus infection.

Case Report: Multiple Organ Failure Caused by Hemorrhagic Fever with Renal Syndrome

Hemorrhagic fever with renal syndrome (HFRS), a natural epidemic disease caused by hantavirus (HV), is one of the viral diseases that pose a major threat to our health. Considering the increasing number of atypical-onset cases reported in some countries, it is important to be familiar with the symptoms of HFRS and the signs of HV infection. This report describes the case of a 55-year-old man with complaints of fever, vomiting, and diarrhea. His symptoms showed no significant improvement after routine anti-infective, antipyretic, and other symptomatic supportive treatments administered at a local clinic. During these treatments, the patient had progressive oliguria; after 3 days, he also developed multiple organ failures, such as the liver and kidney, and was examined for positive serum IgM antibodies to hemorrhagic fever during treatment at our hospital. The patient was finally diagnosed with HFRS followed by multiple organ failure. After antiviral therapy, including ribavirin, piperacillin, and tazobactam, continuous renal replacement therapy, fluid metabolism adjustment, and related supportive therapy were administered, which improved his liver and kidney function. He was discharged on the 25th day after hospitalization. It is difficult to manage patients who develop multiple organ failure after HFRS. Moreover, this condition is rare in clinical settings, with fever being the initial indication. For diseases with unknown origin such as refractory fever and diarrhea, it is crucial to differentiate them from common pathogenic infection and HV infections to provide timely treatment that improves the prognosis of patients.

The Spatiotemporal Pattern and Its Determinants of Hemorrhagic Fever With Renal Syndrome in Northeastern China: Spatiotemporal Analysis

BACKGROUND

Hemorrhagic fever with renal syndrome (HFRS) is a significant zoonotic disease mainly transmitted by rodents. However, the determinants of its spatiotemporal patterns in Northeast China remain unclear.

OBJECTIVE

This study aimed to investigate the spatiotemporal dynamics and epidemiological characteristics of HFRS and detect the meteorological effect of the HFRS epidemic in Northeastern China.

METHODS

The HFRS cases of Northeastern China were collected from the Chinese Center for Disease Control and Prevention, and meteorological data were collected from the National Basic Geographic Information Center. Times series analyses, wavelet analysis, Geodetector model, and SARIMA model were performed to identify the epidemiological characteristics, periodical fluctuation, and meteorological effect of HFRS in Northeastern China.

RESULTS

A total of 52,655 HFRS cases were reported in Northeastern China from 2006 to 2020, and most patients with HFRS (n=36,558, 69.43%) were aged between 30-59 years. HFRS occurred most frequently in June and November and had a significant 4- to 6-month periodicity. The explanatory power of the meteorological factors to HFRS varies from 0.15 ≤ q ≤ 0.01. In Heilongjiang province, mean temperature with a 4-month lag, mean ground temperature with a 4-month lag, and mean pressure with a 5-month lag had the most explanatory power on HFRS. In Liaoning province, mean temperature with a 1-month lag, mean ground temperature with a 1-month lag, and mean wind speed with a 4-month lag were found to have an effect on HFRS, but in Jilin province, the most important meteorological factors for HFRS were precipitation with a 6-month lag and maximum evaporation with a 5-month lag. The interaction analysis of meteorological factors mostly showed nonlinear enhancement. The SARIMA model predicted that 8,343 cases of HFRS are expected to occur in Northeastern China.

CONCLUSIONS

HFRS showed significant inequality in epidemic and meteorological effects in Northeastern China, and eastern prefecture-level cities presented a high risk of epidemic. This study quantifies the hysteresis effects of different meteorological factors and prompts us to focus on the influence of ground temperature and precipitation on HFRS transmission in future studies, which could assist local health authorities in developing HFRS-climate surveillance, prevention, and control strategies targeting high-risk populations in China.

Hemorrhagic Fever with Renal Syndrome in Asia: History, Pathogenesis, Diagnosis, Treatment, and Prevention

Hemorrhagic Fever with Renal Syndrome (HFRS) is the most frequently diagnosed zoonosis in Asia. This zoonotic infection is the result of exposure to the virus-contaminated aerosols. Orthohantavirus infection may cause Hemorrhagic Fever with Renal Syndrome (HRFS), a disease that is characterized by acute kidney injury and increased vascular permeability. Several species of orthohantaviruses were identified as causing infection, where Hantaan, Puumala, and Seoul viruses are most common. Orthohantaviruses are endemic to several Asian countries, such as China, South Korea, and Japan. Along with those countries, HFRS tops the list of zoonotic infections in the Far Eastern Federal District of Russia. Recently, orthohantavirus circulation was demonstrated in small mammals in Thailand and India, where orthohantavirus was not believed to be endemic. In this review, we summarized the current data on orthohantaviruses in Asia. We gave the synopsis of the history and diversity of orthohantaviruses in Asia. We also described the clinical presentation and current understanding of the pathogenesis of orthohantavirus infection. Additionally, conventional and novel approaches for preventing and treating orthohantavirus infection are discussed.

Characterization of a Panel of Cross-Reactive Hantavirus Nucleocapsid Protein-Specific Monoclonal Antibodies

Hantaviruses are emerging pathogens with a worldwide distribution that can cause life-threatening diseases in humans. Monoclonal antibodies (MAbs) against hantavirus nucleocapsid (N) proteins are important tools in virus diagnostics, epidemiological studies and basic research studies on virus replication and pathogenesis. Here, we extend the collection of previously generated MAbs raised against a segment of Puumala orthohantavirus (PUUV) N protein harbored on virus-like particles (VLPs) and MAbs against N proteins of Sin Nombre orthohantavirus/Andes orthohantavirus by generating nine novel MAbs against N proteins of Dobrava-Belgrade orthohantavirus (DOBV), Tula orthohantavirus (TULV), Thottapalayam thottimvirus (TPMV) and PUUV. In order to have a wide collection of well-described hantavirus-specific MAbs, the cross-reactivity of novel and previously generated MAbs was determined against N proteins of 15 rodent- and shrew-borne hantaviruses by different immunological methods. We found that all MAbs, excluding TPMV-specific MAbs, demonstrated different cross-reactivity patterns with N proteins of hantaviruses and recognized native viral antigens in infected mammalian cells. This well-characterized collection of cross-reactive hantavirus-specific MAbs has a potential application in various fields of hantavirus research, diagnostics and therapy.

Advances in fluorescence microscopy for orthohantavirus research

Orthohantaviruses are important zoonotic pathogens responsible for a considerable disease burden globally. Partly due to our incomplete understanding of orthohantavirus replication, there is currently no effective antiviral treatment available. Recently, novel microscopy techniques and cutting-edge, automated image analysis algorithms have emerged, enabling to study cellular, subcellular and even molecular processes in unprecedented detail and depth. To date, fluorescence light microscopy allows us to visualize viral and cellular components and macromolecular complexes in live cells which in turn enables the study of specific steps of the viral replication cycle such as particle entry or protein trafficking at high temporal and spatial resolution. In this review, we highlight how fluorescence microscopy has provided new insights and improved our understanding of orthohantavirus biology. We discuss technical challenges such as studying live infected cells, give alternatives with recombinant protein expression and highlight future opportunities for example the application of super-resolution microscopy techniques, which has shown great potential in studies of different cellular processes and viral pathogens.

Hantaan virus-induced elevation of plasma osteoprotegerin and its clinical implications in hemorrhagic fever with renal syndrome

OBJECTIVES

The bleeding tendency is a hallmark of hemorrhagic fever with renal syndrome (HFRS) after Hantaan virus (HTNV) infection. Growing reports indicate the importance of osteoprotegerin (OPG) in vascular homeostasis, implying OPG might be involved in the pathogenesis of coagulopathy in patients with HFRS.

METHODS

Acute and convalescence plasmas of 32 patients with HFRS were collected. Enzyme-linked immunosorbent assays (ELISA) were used to detect plasma OPG levels and other parameters. The human umbilical vein endothelial cells were stimulated with HTNV and/or tumor necrosis factor-α (TNF-α) to explore the source of OPG.

RESULTS

Plasma OPG levels of patients with HFRS were elevated and correlated positively with the severity of HFRS and negatively with platelet counts. Abundant OPG was released from endothelial cells in response to TNF-α stimuli, along with HTNV infection, which was in accordance with the findings of positive correlations between plasma OPG and TNF-α or c-reactive protein. Importantly, plasma OPG levels correlated positively with activated partial thromboplastin time and the content of d-dimer.

CONCLUSION

These findings suggested that increased plasma OPG levels induced by HTNV might be an important factor for the severity of HFRS, and was likely involved in endothelium dysfunction and hemorrhagic disorder of HFRS, which might contribute to the pathogenesis of hemorrhage in HFRS.

High levels of exfoliated fragments following glycocalyx destruction in hemorrhagic fever with the renal syndrome are associated with mortality risk

Background

The glycocalyx is a gel-like structure that covers the luminal side of vascular endothelial cells. It plays an important role in maintaining the integrity of the vascular endothelial barrier structure. However, the presence or absence of glycocalyx destruction in hemorrhagic fever with renal syndrome (HFRS) and its specific mechanism and role is still unclear.

Methods

In this study, we detected the levels of exfoliated glycocalyx fragments, namely, heparan sulfate (HS), hyaluronic acid (HA), and chondroitin sulfate (CS), in HFRS patients and investigated their clinical application value on the evaluation of disease severity and prognosis prediction.

Results

The expression of exfoliated glycocalyx fragments in plasma was significantly increased during the acute stage of HFRS. The levels of HS, HA, and CS in HFRS patients during the acute stage were significantly higher than in healthy controls and convalescent stages of the same type. HS and CS during the acute stage gradually increased with the aggravation of HFRS, and both fragments showed a significant association with disease severity. In addition, exfoliated glycocalyx fragments (especially HS and CS) showed a significant correlation with conventional laboratory parameters and hospitalization days. High levels of HS and CS during the acute phase were significantly associated with patient mortality and demonstrated an obvious predictive value for the mortality risk of HFRS.

Conclusion

Glycocalyx destruction and shedding may be closely associated with endothelial hyperpermeability and microvascular leakage in HFRS. The dynamic detection of the exfoliated glycocalyx fragments may be beneficial for the evaluation of disease severity and prognosis prediction in HFRS.

An algal lectin griffithsin inhibits Hantaan virus infection in vitro and in vivo

Hantaan virus (HTNV) is the etiological pathogen of hemorrhagic fever with renal syndrome in East Asia. There are currently no effective therapeutics approved for HTNV and other hantavirus infections. We found that griffithsin (GRFT), an algae-derived lectin with broad-spectrum antiviral activity against various enveloped viruses, can inhibit the growth and spread of HTNV. In vitro experiments using recombinant vesicular stomatitis virus (rVSV) with HTNV glycoproteins as a model revealed that the GRFT inhibited the entry of rVSV-HTNV-G into host cells. In addition, we demonstrated that GRFT prevented authentic HTNV infection in vitro by binding to the viral N-glycans. In vivo experiments showed that GRFT partially protected the suckling mice from death induced by intracranial exposure to HTNV. These results demonstrated that GRFT can be a promising agent for inhibiting HTNV infection.

Expert Consensus on the Prevention and Treatment of Hemorrhagic Fever with Renal Syndrome

Abstract

Hemorrhagic fever with renal syndrome (HFRS) is an acute zoonosis with a global distribution. China is one of the countries with a high incidence of HFRS, which has long endangered the lives and health of the Chinese people. The Infectious Disease Branch of the Chinese Preventive Medicine Association and the Infectious Diseases Branch of the Chinese Medical Association organized national multidisciplinary experts, based on domestic and international research results combined with experts’ practical experiences, to reach this consensus after thorough discussion. This consensus contains 17 recommendations aimed at prevention and identification of important clinical issues to further standardize the prevention, diagnosis, and treatment of HFRS.

Trends and focuses of hantavirus researches: a global bibliometric analysis and visualization from 1980 to 2020

Background

There have been worldwide changes in the researches on hantaviruses in the past several decades. Nevertheless, there are few bibliometric analysis studies this field. We aim to evaluate and visualize the research focuses and trends of this field using a bibliometric analysis way to help understand the developmet and future hotspots of this field.

Material and methods

Publications related to hantavirus studies were culled from the Web of Science Core Collection to generate trend analysis. The articles and reviews were re-extracted and Countries, institutions, authors, references and keywords in this field were visually analyzed by using VOSviewer and CiteSpace.

Results

A total of 4408 studies were included and the number of publications regarding hantaviruses significantly increased yearly. Three thousand seven hundred sixteen research articles and reviews were retrieved to generate bibliometric analysis. These studies mainly come from 125 countries led by USA and China and 3312 institutions led by the University of Helsinki. Twelve thousand five hundred twenty nine authors were identified and Vaheri A were the most influential author. Journal of Virology was the journal with the most studies and citations. After analysis, Hemorrhagic fever with renal syndrome, Hantavirus cardiopulmonary syndrome, nephropathia epidemica and related genotypes, clinical symptoms and rodents were the most common keywords and developing areas.

Conclusion

Research on hantavirus is flourishing. Cooperation among different countries and institutions in this field must be strengthened in the future. The ecology and clinical symptoms of new genotypes, the vaccine development and factors that affect host population distribution and density are current and developing areas of study.

Dihydropyridine-derived calcium channel blocker as a promising anti-hantavirus entry inhibitor

Hantaviruses, the causative agent for two types of hemorrhagic fevers, hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS), are distributed from Eurasia to America. HFRS and HPS have mortality rates of up to 15% or 45%, respectively. Currently, no certified therapeutic has been licensed to treat hantavirus infection. In this study, we discovered that benidipine hydrochloride, a calcium channel blocker, inhibits the entry of hantaviruses in vitro. Moreover, an array of calcium channel inhibitors, such as cilnidipine, felodipine, amlodipine, manidipine, nicardipine, and nisoldipine, exhibit similar antiviral properties. Using pseudotyped vesicular stomatitis viruses harboring the different hantavirus glycoproteins, we demonstrate that benidipine hydrochloride inhibits the infection by both HFRS- and HPS-causing hantaviruses. The results of our study indicate the possibility of repurposing FDA-approved calcium channel blockers for the treatment of hantavirus infection, and they also indicate the need for further research in vivo.

LncRNA NEAT1 Potentiates SREBP2 Activity to Promote Inflammatory Macrophage Activation and Limit Hantaan Virus Propagation

As the global prototypical zoonotic hantavirus, Hantaan virus (HTNV) is prevalent in Asia and is the leading causative agent of severe hemorrhagic fever with renal syndrome (HFRS), which has profound morbidity and mortality. Macrophages are crucial components of the host innate immune system and serve as the first line of defense against HTNV infection. Previous studies indicated that the viral replication efficiency in macrophages determines hantavirus pathogenicity, but it remains unknown which factor manipulates the macrophage activation pattern and the virus-host interaction process. Here, we performed the transcriptomic analysis of HTNV-infected mouse bone marrow-derived macrophages and identified the long noncoding RNA (lncRNA) nuclear enriched abundant transcript 1 (NEAT1), especially the isoform NEAT1-2, as one of the lncRNAs that is differentially expressed at the early phase. Based on coculture experiments, we revealed that silencing NEAT1-2 hinders inflammatory macrophage activation and facilitates HTNV propagation, while enhancing NEAT1-2 transcription effectively restrains viral replication. Furthermore, sterol response element binding factor-2 (SREBP2), which controls the cholesterol metabolism process, was found to stimulate macrophages by promoting the production of multiple inflammatory cytokines upon HTNV infection. NEAT1-2 could potentiate SREBP2 activity by upregulating Srebf1 expression and interacting with SREBP2, thus stimulating inflammatory macrophages and limiting HTNV propagation. More importantly, we demonstrated that the NEAT1-2 expression level in patient monocytes was negatively correlated with viral load and HFRS disease progression. Our results identified a function and mechanism of action for the lncRNA NEAT1 in heightening SREBP2-mediated macrophage activation to restrain hantaviral propagation and revealed the association of NEAT1 with HFRS severity.

Design of a Multi-Epitopes Vaccine against Hantaviruses: An Immunoinformatics and Molecular Modelling Approach

Hantaviruses are negative-sense, enveloped, single-stranded RNA viruses of the family Hantaviridae. In recent years, rodent-borne hantaviruses have emerged as novel zoonotic viruses posing a substantial health issue and socioeconomic burden. In the current research, a reverse vaccinology approach was applied to design a multi-epitope-based vaccine against hantavirus. A set of 340 experimentally reported epitopes were retrieved from Virus Pathogen Database and Analysis Resource (ViPR) and subjected to different analyses such as antigenicity, allergenicity, solubility, IFN gamma, toxicity, and virulent checks. Finally, 10 epitopes which cleared all the filters used were linked with each other through specific GPGPG linkers to construct a multi-antigenic epitope vaccine. The designed vaccine was then joined to three different adjuvants-TLR4-agonist adjuvant, β-defensin, and 50S ribosomal protein L7/L12-using an EAAAK linker to boost up immune-stimulating responses and check the potency of vaccine with each adjuvant. The designed vaccine structures were modelled and subjected to error refinement and disulphide engineering to enhance their stability. To understand the vaccine binding affinity with immune cell receptors, molecular docking was performed between the designed vaccines and TLR4; the docked complex with a low level of global energy was then subjected to molecular dynamics simulations to validate the docking results and dynamic behaviour. The docking binding energy of vaccines with TLR4 is -29.63 kcal/mol (TLR4-agonist), -3.41 kcal/mol (β-defensin), and -11.03 kcal/mol (50S ribosomal protein L7/L12). The systems dynamics revealed all three systems to be highly stable with a root-mean-square deviation (RMSD) value within 3 Å. To test docking predictions and determine dominant interaction energies, binding free energies of vaccine(s)-TLR4 complexes were calculated. The net binding energy of the systems was as follows: TLR4-agonist vaccine with TLR4 (MM-GBSA, -1628.47 kcal/mol and MM-PBSA, -37.75 kcal/mol); 50S ribosomal protein L7/L12 vaccine with TLR4 complex (MM-GBSA, -194.62 kcal/mol and MM-PBSA, -150.67 kcal/mol); β-defensin vaccine with TLR4 complex (MM-GBSA, -9.80 kcal/mol and MM-PBSA, -42.34 kcal/mol). Finally, these findings may aid experimental vaccinologists in developing a very potent hantavirus vaccine.

Hantavirus Induced Kidney Disease

Hantavirus induced hemorrhagic fever with renal syndrome (HFRS) is an emerging viral zoonosis affecting up to 200,000 humans annually worldwide. This review article is focused on recent advances in the mechanism, epidemiology, diagnosis, and treatment of hantavirus induced HFRS. The importance of interactions between viral and host factors in the design of therapeutic strategies is discussed. Hantavirus induced HFRS is characterized by thrombocytopenia and proteinuria of varying severities. The mechanism of kidney injury appears immunopathological with characteristic deterioration of endothelial cell function and compromised barrier functions of the vasculature. Although multidisciplinary research efforts have provided insights about the loss of cellular contact in the endothelium leading to increased permeability, the details of the molecular mechanisms remain poorly understood. The epidemiology of hantavirus induced renal failure is associated with viral species and the geographical location of the natural host of the virus. The development of vaccine and antiviral therapeutics is necessary to avoid potentially severe outbreaks of this zoonotic illness in the future. The recent groundbreaking approach to the SARS-CoV-2 mRNA vaccine has revolutionized the general field of vaccinology and has provided new directions for the use of this promising platform for widespread vaccine development, including the development of hantavirus mRNA vaccine. The combinational therapies specifically targeted to inhibit hantavirus replication and vascular permeability in infected patients will likely improve the disease outcome.

Coumarin Derivative N6 as a Novel anti-hantavirus Infection Agent Targeting AKT

Hantaviruses are globally emerging zoonotic viruses that can cause hemorrhagic fever with renal syndrome (HFRS) in Asia and Europe, which is primarily caused by Hantaan virus (HTNV) infection, results in profound morbidity and mortality. However, no specific treatment is available for this disease. Coumarin derivatives have been reported as antiviral molecules, while studies about the bioactivity of coumarin derivatives against HTNV infection are limited. To study the potential antiviral activity of coumarin derivatives, 126 coumarin derivatives are synthesized, and their inhibitory activity against HTNV is analyzed in vitro. Among these compounds, N6 inhibits HTNV with relatively high selectivity index at 10.9, and the viral titer of HTNV is reduced significantly after 5, 10, and 20 μM N6 treatments. Furthermore, the administration of N6 at the early stage of HTNV infection can inhibit the replication and production of infectious HTNV in host cell, this therapeutic efficacy is confirmed in HTNV-infected newborn mice at the early stage of infection. The molecular docking results show that N6 forms interactions with the key amino acid residues at its active site, and reveals several molecular interactions responsible for the observed affinity, and the treatment of N6 can inhibit the expression of p (Ser473)Akt and HTNV nucleocapsid protein significantly. As such, these observations demonstrate that coumarin derivative N6 might be used as a potential agent against HTNV infection.

Hantavirus Cardiopulmonary Syndrome and Diffuse Alveolar Hemorrhage in the Era of COVID-19

Hantavirus Cardiopulmonary Syndrome (HCPS) can occur after infection with Hantavirus which can occur by inhaling aerosolized rodent urine, feces, and saliva contaminated with the virus. It presents with the rapid development of pulmonary edema, respiratory failure, and cardiogenic shock with the hallmark being microvascular leakage. We report a patient with a history of alcohol abuse and recent exposure to mice and sick kittens who presented with cough with sputum production, shortness of breath, orthopnea, and new-onset lower extremity edema. Imaging revealed bilateral infiltrates more common on the left with an unremarkable echocardiogram. Testing for COVID-19, Human Immunodeficiency Virus (HIV), influenza, bacterial pneumonia including tuberculosis and methicillin-resistant Staphylococcus aureus (MRSA), aspergillosis, histoplasmosis, Blastomyces, and Coccidiodes was negative. Bronchoscopy and bronchoalveolar lavage revealed diffuse alveolar hemorrhage (DAH) and were negative for acid-fast bacilli and Nocardia cultures. He was further tested for Hantavirus, Q fever, leptospirosis, toxoplasmosis, and empiric treatment with doxycycline initiated. His Hantavirus IgM antibody came back positive. Human Hantavirus infection occurs after inhalation of infected rodent excreta; fortunately, human-to-human transmission has not been documented. HCPS most commonly occurs due to the Sin Nombre virus (SNV), has a case fatality rate of 50%, and is a notifiable disease in the United States. It has 3 distinct phases, prodromal, cardiopulmonary, and convalescent/recovery. The cardiopulmonary phase occurs from increased permeability of pulmonary capillaries and in severe cases can progress to cardiogenic shock. Diagnosis is based on the presence of IgM and IgG Hantavirus antibodies. Treatment is mainly supportive; however, patients are usually treated with broad-spectrum antibiotics while workup is underway. In animal models, ribavirin and favipiravir are only effective when administered in the prodromal phase. If suspicion of Hantavirus infection exists, early mobilization to the intensive care unit for treatment is recommended. Extracorporeal membrane oxygenation (ECMO) has been suggested to improve outcomes in severe HCPS with refractory shock.

New class of hantaan virus inhibitors based on conjugation of the isoindole fragment to (+)-camphor or (-)-fenchone hydrazonesv

This work presents the design and synthesis of camphor, fenchone, and norcamphor N-acylhydrazone derivatives as a new class of inhibitors of the Hantaan virus, which causes haemorrhagic fever with renal syndrome (HFRS). A cytopathic model was developed for testing chemotherapeutics against the Hantaan virus, strain 76-118. In addition, a study of the antiviral activity was carried out using a pseudoviral system. It was found that the hit compound possesses significant activity (IC₅₀ = 7.6 ± 2 µM) along with low toxicity (CC₅₀ > 1000 µM). Using molecular docking procedures, the binding with Hantavirus nucleoprotein was evaluated and the correlation between the structure of the synthesised compounds and the antiviral activity was established.

Ocular manifestations of emerging viral diseases

Emerging infectious diseases (EIDs) are an increasing threat to public health on a global scale. In recent times, the most prominent outbreaks have constituted RNA viruses, spreading via droplets (COVID-19 and Influenza A H1N1), directly between humans (Ebola and Marburg), via arthropod vectors (Dengue, Zika, West Nile, Chikungunya, Crimean Congo) and zoonotically (Lassa fever, Nipah, Rift Valley fever, Hantaviruses). However, specific approved antiviral therapies and vaccine availability are scarce, and public health measures remain critical. Patients can present with a spectrum of ocular manifestations. Emerging infectious diseases should therefore be considered in the differential diagnosis of ocular inflammatory conditions in patients inhabiting or returning from endemic territories, and more general vigilance is advisable in the context of a global pandemic. Eye specialists are in a position to facilitate swift diagnosis, improve clinical outcomes, and contribute to wider public health efforts during outbreaks. This article reviews those emerging viral diseases associated with reports of ocular manifestations and summarizes details pertinent to practicing eye specialists.

Electrochemical determination of hantavirus using gold nanoparticle-modified graphene as an electrode material and Cu-based metal-organic framework assisted signal generation

An electrochemical biosensor was prepared for nucleic acid-based hantavirus detection using a Cu-based metal-organic framework (CuMOF) as a signal tag. The CuMOF was synthesized by the solvothermal method and then covalently bonded with signal DNA (sDNA) probes. The Au nanoparticles and reduced graphene oxide composite were deposited on the electrode surface by electroreduction as support substrate and was then functionalized with capture DNA (cDNA) probes by self-assembly. Through the complementary base pairing, the target DNA (tDNA) fragment of hantavirus hybridized with the cDNA and the sDNA in a sandwich-type format. The tDNA was detected according to the current signal of the CuMOF catalyzed reaction using o-phenylenediamine as redox substrate. The peak current of the biosensor at - 0.55 V increased linearly in proportion to the logarithmic value of the tDNA concentration from 10^-15 to 10^-9 mol/L, with a detection limit of 0.74 × 10^-15 mol/L. Moreover, the proposed biosensor was successfully applied to detect hantavirus and was able to distinguish hantavirus from other arboviruses.

An evaluation of suspected cases of Hantavirus infection admitted to a tertiary care university hospital in Düzce, Turkey, between 2012 and 2018

Background/aim

Hantavirus is a rodent borne zoonosis caused by the members of the virus family Bunyaviridae, genus Hantavirus . In this study, we aimed to determine the role of peripheral blood leukocyte ratio in differential diagnosis of Hantavirus disease.

Materials and methods

The medical records of patients at the Düzce University Medical Faculty were examined retrospectively. A total of 20 patients diagnosed with hantavirus infection confirmed by serologic tests were included in the study (Group 1). The other group consisted of 30 patients suspected of hantavirus infection but found negative (Group 2). Demographic, clinical and laboratory characteristics, neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), and lymphocyte/monocyte (LMR) ratios of both groups were compared.

Results

As a result of the istatistics analysis, no difference was found between the groups’ age, sex, and clinical complaints except lethargy-weakness (P = 0.004) and diarrhea (P < 0.001). Hemogram analysis showed a significant difference between the groups in terms of leukocyte, hemoglobin, hematocrit, platelet, mean platelet volume (P < 0.05) and PLR (P = 0.001) and LMR (P = 0.003) values from peripheral blood leukocyte ratios.

Conclusion

In conclusion, NLR, PLR, and LMR ratios may be useful for clinicians in differential diagnosis of Hantavirus in patients presenting with similar symptoms of Hantavirus disease.

Human infection with Seoul orthohantavirus in Korea, 2019

Of various rodent-borne hantaviruses, Seoul orthohantavirus (SEOV) causes haemorrhagic fever with renal syndrome (HFRS), as does Hantaan orthohantavirus (HTNV). Given global-scale of cases of human infection with SEOV, it is of great clinical importance to distinguish SEOV from other HFRS-causing hantaviruses. In May 2019, a middle-aged patient who had lived in a suburban area of Chungcheong Province, Republic of Korea and enjoyed outdoor activities was transferred to Asan Medical Center in Seoul, Republic of Korea with HFRS; his symptoms included high fever and generalized myalgia. The rapid diagnostic test performed immediately after his transfer detected HTNV-specific antibodies, and the patient was treated accordingly. However, two consecutive IFAs performed at ten-day intervals showed no HTNV-specific immunoglobulin (Ig) G. During continuous supportive care, next-generation sequencing successfully identified viral genomic sequences in the patient’s serum, which were SEOV and not HTNV. Phylogenetic analysis grouped the L, M, and S genes of this SEOV strain together with those of rat- or human-isolated Korean strains reported previously. Given global outbreaks and public health threats of zoonotic hantaviruses, a causative pathogen of hantavirus HFRS should be identified correctly at the time of diagnosis and by point-of-care testing.

Rodent-borne Seoul orthohantavirus (SEOV) has provoked human cases from Asia to the Americas and Europe whereas most orthohantaviruses cause regional cases. Despite this, SEOV gets less attention than other orthohantaviruses. In Korea, 2019, a middle-aged man was initially diagnosed with Hantaan orthohantavirus (HTNV) and treated accordingly. However, next-generation sequencing identified SEOV, not HTNV, in the patient’s serum. Given its global outbreaks and public health threats, zoonotic SEOV should be diagnosed correctly on point of care to reduce unnecessary medical costs.

Case Report: Spinal Subarachnoid Hemorrhage: A Rare Complication of Hemorrhagic Fever with Renal Syndrome

Hemorrhagic fever with renal syndrome (HFRS), caused by hantavirus, is occasionally seen in tropical areas. The virus is carried by specific rodent host species. Hemorrhagic fever with renal syndrome is characterized by renal failure and hemorrhagic manifestations, and its complications may be severe, including massive bleeding, multi-organ dysfunction, and possibly death. In this patient case, a 46-year-old woman diagnosed with HFRS initially presented with fever, impaired function, and thrombocytopenia. Four days after symptom onset, the patient complained of abrupt right lower abdominal pain and numbness. Magnetic resonance imaging revealed a spinal subarachnoid hemorrhage (SAH) beyond the T7 to S2 vertebrae. No cases of spinal SAH in HFRS have been reported until now. This case demonstrates that when a patient's symptoms are atypical, bleeding-related complications must be considered.

Genomic Epidemiology and Active Surveillance to Investigate Outbreaks of Hantaviruses

Emerging and re-emerging RNA viruses pose significant public health, economic, and societal burdens. Hantaviruses (genus Orthohantavirus, family Hantaviridae, order Bunyavirales) are enveloped, negative-sense, single-stranded, tripartite RNA viruses that are emerging zoonotic pathogens harbored by small mammals such as rodents, bats, moles, and shrews. Orthohantavirus infections cause hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome in humans (HCPS). Active targeted surveillance has elucidated high-resolution phylogeographic relationships between patient- and rodent-derived orthohantavirus genome sequences and identified the infection source by temporally and spatially tracking viral genomes. Active surveillance of patients with HFRS entails 1) recovering whole-genome sequences of Hantaan virus (HTNV) using amplicon (multiplex PCR-based) next-generation sequencing, 2) tracing the putative infection site of a patient by administering an epidemiological questionnaire, and 3) collecting HTNV-positive rodents using targeted rodent trapping. Moreover, viral genome tracking has been recently performed to rapidly and precisely characterize an outbreak from the emerging virus. Here, we reviewed genomic epidemiological and active surveillance data for determining the emergence of zoonotic RNA viruses based on viral genomic sequences obtained from patients and natural reservoirs. This review highlights the recent studies on tracking viral genomes for identifying and characterizing emerging viral outbreaks worldwide. We believe that active surveillance is an effective method for identifying rodent-borne orthohantavirus infection sites, and this report provides insights into disease mitigation and preparedness for managing emerging viral outbreaks.

A comprehensive screening of the whole proteome of hantavirus and designing a multi-epitope subunit vaccine for cross-protection against hantavirus: Structural vaccinology and immunoinformatics study

Hantaviruses are an emerging zoonotic group of rodent-borne viruses that are having serious implications on global public health due to the increase in outbreaks. Since there is no permanent cure, there is increasing interest in developing a vaccine against the hantavirus. This research aimed to design a robust cross-protective subunit vaccine using a novel immunoinformatics approach. After careful evaluation, the best predicted cytotoxic & helper T-cell and B-cell epitopes from nucleocapsid proteins, glycoproteins, RdRp proteins, and non-structural proteins were considered as potential vaccine candidates. Among the four generated vaccine models with different adjuvant, the model with toll-like receptor-4 (TLR-4) agonist adjuvant was selected because of its high antigenicity, non-allergenicity, and structural quality. The selected model was 654 amino acids long and had a molecular weight of 70.5 kDa, which characterizes the construct as a good antigenic vaccine candidate. The prediction of the conformational B-lymphocyte (CBL) epitope secured its ability to induce the humoral response. Thereafter, disulfide engineering improved vaccine stability. Afterwards, the molecular docking confirmed a good binding affinity of -1292 kj/mol with considered immune receptor TLR-4 and the dynamics simulation showed high stability of the vaccine-receptor complex. Later, the in silico cloning confirmed the better expression of the constructed vaccine protein in E. coli K12. Finally, in in silico immune simulation, significantly high levels of immunoglobulin M (IgM), immunoglobulin G1 (IgG1), cytotoxic & helper T lymphocyte (CTL & HTL) populations, and numerous cytokines such as interferon-γ (IFN-γ), interleukin-2 (IL-2) etc. were found as coherence with actual immune response and also showed faster antigen clearance for repeated exposures. Nonetheless, experimental validation can demonstrate the safety and cross-protective ability of the proposed vaccine to fight against hantavirus infection.

Biosensors for the Detection of Bacterial and Viral Clinical Pathogens

Biosensors are measurement devices that can sense several biomolecules, and are widely used for the detection of relevant clinical pathogens such as bacteria and viruses, showing outstanding results. Because of the latent existing risk of facing another pandemic like the one we are living through due to COVID-19, researchers are constantly looking forward to developing new technologies for diagnosis and treatment of infections caused by different bacteria and viruses. Regarding that, nanotechnology has improved biosensors' design and performance through the development of materials and nanoparticles that enhance their affinity, selectivity, and efficacy in detecting these pathogens, such as employing nanoparticles, graphene quantum dots, and electrospun nanofibers. Therefore, this work aims to present a comprehensive review that exposes how biosensors work in terms of bacterial and viral detection, and the nanotechnological features that are contributing to achieving a faster yet still efficient COVID-19 diagnosis at the point-of-care.

Hantavirus Infection during Pregnancy

Hantavirus infection is a global health challenge, causing widespread public concern. In recent years, cases of hantavirus infection in pregnant women have been reported in many countries. The infected pregnant women and their fetuses appear to have more severe clinical symptoms and worse clinical outcomes. Hence, to study the prevalence of hantavirus infection in pregnant women, this study will focus on the epidemiological distribution of the virus, different virus species penetrating the placental barrier, and factors affecting the incidence and clinical outcome of the infection in pregnant women and their fetuses. In addition, this review will also discuss the diagnostic tools and treatments for pregnant patients and provide an overview of the relevant future research.

Biodefense Implications of New-World Hantaviruses

Hantaviruses, part of the Bunyaviridae family, are a genus of negative-sense, single-stranded RNA viruses that cause two major diseases: New-World Hantavirus Cardiopulmonary Syndrome and Old-World Hemorrhagic Fever with Renal Syndrome. Hantaviruses generally are found worldwide with each disease corresponding to their respective hemispheres. New-World Hantaviruses spread by specific rodent-host reservoirs and are categorized as emerging viruses that pose a threat to global health and security due to their high mortality rate and ease of transmission. Incidentally, reports of Hantavirus categorization as a bioweapon are often contradicted as both US National Institute of Allergy and Infectious Diseases and the Centers for Disease Control and Prevention refer to them as Category A and C bioagents respectively, each retaining qualitative levels of importance and severity. Concerns of Hantavirus being engineered into a novel bioagent has been thwarted by Hantaviruses being difficult to culture, isolate, and purify limiting its ability to be weaponized. However, the natural properties of Hantaviruses pose a threat that can be exploited by conventional and unconventional forces. This review seeks to clarify the categorization of Hantaviruses as a bioweapon, whilst defining the practicality of employing New-World Hantaviruses and their effect on armies, infrastructure, and civilian targets.