Hantavirus infection-related acute inflammatory demyelinative polyradiculoneuropathy: A case report and literature review

RATIONALE

Hemorrhagic fever with renal syndrome (HFRS) is a common infectious disease in China. As a complication of post-Hantavirus infection, Guillain-Barre syndrome (GBS) was rarely previously reported. Here, we described a case of acute inflammatory demyelinative polyradiculoneuropathy secondary to Hantavirus infection in spring of 2023. We also made a summary of the clinical features from previous reported cases.

PATIENT CONCERNS

A young male patient complained a fever with headache, who was subsequently diagnosed with HFRS with positive serum Hantavirus antibody IgM. Two weeks later, he presented sustained back pain, obvious numbness located in 4 extremities, chest and abdomen, facial dyskinesia and 4 extremities muscle weakness.

DIAGNOSIS, INTERVENTIONS, AND OUTCOMES

He was rapidly diagnosed with GBS by typical cerebrospinal fluid change and the electromyography examination presentation, which was verified associated with hantavirus infection. He was treated with intravenous immunoglobulin infusion followed by rehabilitation treatment. He got a complete recovery within 4 months after disease onset.

LESSONS

GBS was an uncommon manifestation of Hantavirus infection. GBS should be considered when acute limb weakness happens in cases with HFRS. A multidisciplinary team could make a rapid diagnosis and optimal treatment when nervous system disorders occurred.

Favorable course of leptospirosis and hantavirus-induced acute tubulointerstitial nephritis under corticosteroid treatment

BACKGROUND

We present two children with acute tubulointerstitial nephritis (ATIN) caused by leptospirosis in a 12-year-old boy and hantavirus in a 10-year-old girl. The role of glucocorticoids in the management of ATIN triggered by infectious agents is unclear.

CASE-DIAGNOSIS/TREATMENT

Both children were hospitalized with jaundice, elevated serum creatinine, and thrombocytopenia. There was no oliguria or hypertension. Urine analysis revealed tubular proteinuria. Kidney biopsy was performed on one patient and showed tubulointerstitial inflammation with mild mesangial proliferation. Both patients were treated with glucocorticoids in view of deteriorating kidney function with respective serum creatinine values of 5.2 and 4.1 mg/dl. Both children exhibited an excellent clinical and biochemical response to treatment. Neither of the patients required dialysis. Positive serology test results indicated a recent leptospirosis and hantavirus infection.

CONCLUSIONS

Leptospirosis and hantavirus associated ATIN share common clinical and biochemical features. Due to the low incidence in Europe these infectious causes of kidney dysfunction may be overlooked. Glucocorticoids may be considered in the management of ATIN.

Management of Hantavirus Cardiopulmonary Syndrome in Critical Care Transport: A Review

In 1993, the Southwest found itself staring down a disease then known as "unexplained adult respiratory syndrome." During the outbreak, 12 of 23 known patients died. What we now recognize as hantavirus cardiopulmonary syndrome still remains a rare and deadly disease. Although no cure exists, modern supportive techniques such as extracorporeal membrane oxygenation have increased survival among these patients. Early diagnosis has become the primary factor in patient survival. The initial presentation of hantavirus is similar to acute respiratory distress syndrome, necessitating a high index of suspicion to afford the patient the best chance of survival. Diagnosis is further complicated by prolonged and nonspecific incubation periods making it difficult to pinpoint an exposure. Familiarizing oneself with common clinical presentations, diagnostic strategies, and testing is the best way to increase patient survival. Because hantavirus has a predilection for rural areas, transport to a tertiary facility is paramount to provide the resources necessary to care for these complex patients. Rapid sequence intubation, although common in airway-compromised patients, could prove fatal in the setting of the severe hemodynamic instability found in hantavirus cardiopulmonary syndrome. Anticipation of significant pressor use and fluid administration could likely mean the difference in patient mortality during transport.

[Acute interstitial nephritis and hantavirus infection]

Acute interstitial nephritis (AIN) is a cause of acute kidney injury and characterized by an inflammation of the tubulointerstitial space, leading to a decline in kidney function. Multiple etiologies can cause AIN including medications, autoimmune diseases and infections. A multiplicity of drugs is associated with AIN, while antibiotics (especially beta-lactams), proton-pump inhibitors (PPI) and non-steroidal anti-inflammatory agents (NSAIDs) are the most common. The pathognomonic triad of exanthema, fever and eosinophilia is rarely present in AIN patients. Treatment of medication-associated AIN is based upon the discontinuation of the provoking drug. Glucocorticoids can be considered in severe cases.Nephropathia epidemica (NE) is a disease caused by an infection with the Puumula-virus (PUUV) in northern and central Europe. Small rodents (mostly mice) are the host of the virus accountable for a rising number of infections during spring and summer. It is causing a syndrome consisting of AIN, fever and often thrombocytopenia. There is a good chance of complete recovery of kidney function following NE.

External quality assessment of orthohantavirus and lymphocytic choriomeningitis virus molecular detection and serology in Europe, 2021

BackgroundRodent-borne viruses such as orthohantaviruses and arenaviruses cause considerable disease burden with regional and temporal differences in incidence and clinical awareness. Therefore, it is important to regularly evaluate laboratory diagnostic capabilities, e.g. by external quality assessments (EQA).AimWe wished to evaluate the performance and diagnostic capability of European expert laboratories to detect orthohantaviruses and lymphocytic choriomeningitis virus (LCMV) and human antibody response towards orthohantaviruses.MethodsWe conducted an EQA in 2021; molecular panels consisted of 12 samples, including different orthohantaviruses (Seoul, Dobrava-Belgrade (DOBV), Puumala (PUUV) and Hantaan orthohantavirus), LCMV and negative controls. Serological panels consisted of six human serum samples reactive to PUUV, DOBV or negative to orthohantaviruses. The EQA was sent to 25 laboratories in 20 countries.ResultsThe accuracy of molecular detection of orthohantaviruses varied (50‒67%, average 62%) among 16 participating laboratories, while LCMV samples were successfully detected in all 11 participating laboratories (91-100%, average 96%). The accuracy of serological diagnosis of acute and past orthohantavirus infections was on average 95% among 20 participating laboratories and 82% in 19 laboratories, respectively. A variety of methods was used, with predominance of in-house assays for molecular tests, and commercial assays for serological ones.ConclusionSerology, the most common tool to diagnose acute orthohantavirus infections, had a high accuracy in this EQA. The molecular detection of orthohantaviruses needs improvement while LCMV detection (performed in fewer laboratories) had 95% accuracy. Further EQAs are recommended to be performed periodically to monitor improvements and challenges in the diagnostics of rodent-borne diseases.

Hantavirus in humans: a review of clinical aspects and management

Hantavirus infections are part of the broad group of viral haemorrhagic fevers. They are also recognised as a distinct model of an emergent zoonotic infection with a global distribution. Many factors influence their epidemiology and transmission, such as climate, environment, social development, ecology of rodent hosts, and human behaviour in endemic regions. Transmission to humans occurs by exposure to infected rodents in endemic areas; however, Andes hantavirus is unique in that it can be transmitted from person to person. As hantaviruses target endothelial cells, they can affect diverse organ systems; increased vascular permeability is central to pathogenesis. The main clinical syndromes associated with hantaviruses are haemorrhagic fever with renal syndrome (HFRS), which is endemic in Europe and Asia, and hantavirus cardiopulmonary syndrome (HCPS), which is endemic in the Americas. HCPS and HFRS are separate clinical entities, but they share several features and have many overlapping symptoms, signs, and pathogenic alterations. For HCPS in particular, clinical outcomes are highly associated with early clinical suspicion, access to rapid diagnostic testing or algorithms for presumptive diagnosis, and prompt transfer to a facility with critical care units. No specific effective antiviral treatment is available.

[Hantavirus infections]

Hantaviruses are enveloped zoonotic RNA viruses hosted by rodents and responsible in the Americas for hantavirus pulmonary syndrome. In Europe, they cause hemorrhagic fever with renal syndrome and its milder form, nephropathia epidemica. The disease begins abruptly with high fever, chills, headache, back pain and abdominal pain associated with nausea and vomiting. Diagnosis is primarily made by serology. There is currently no specific medication or preventive available in Europe. Treatment is symptomatic.

Use of a Novel Detection Tool to Survey Orthohantaviruses in Wild-Caught Rodent Populations

Orthohantaviruses are negative-stranded RNA viruses with trisegmented genomes that can cause severe disease in humans and are carried by several host reservoirs throughout the world. Old World orthohantaviruses are primarily located throughout Europe and Asia, causing hemorrhagic fever with renal syndrome, and New World orthohantaviruses are found in North, Central, and South America, causing hantavirus cardiopulmonary syndrome (HCPS). In the United States, Sin Nombre orthohantavirus (SNV) is the primary cause of HCPS with a fatality rate of ~36%. The primary SNV host reservoir is thought to be the North American deer mouse, Peromyscus maniculatus. However, it has been shown that other species of Peromyscus can carry different orthohantaviruses. Few studies have systemically surveyed which orthohantaviruses may exist in wild-caught rodents or monitored spillover events into additional rodent reservoirs. A method for the rapid detection of orthohantaviruses is needed to screen large collections of rodent samples. Here, we report a pan-orthohantavirus, two-step reverse-transcription quantitative real-time PCR (RT-qPCR) tool designed to detect both Old and New World pathogenic orthohantavirus sequences of the S segment of the genome and validated them using plasmids and authentic viruses. We then performed a screening of wild-caught rodents and identified orthohantaviruses in lung tissue, and we confirmed the findings by Sanger sequencing. Furthermore, we identified new rodent reservoirs that have not been previously reported as orthohantavirus carriers. This novel tool can be used for the efficient and rapid detection of various orthohantaviruses, while uncovering potential new orthohantaviruses and host reservoirs that may otherwise go undetected.

Hantavirus infections in Italy: not reported doesn't mean inexistent

BACKGROUND

Hantaviruses can cause serious human diseases including hemorrhagic fever with renal syndrome (HFRS) and Hantavirus Cardiopulmonary Syndrome (HCPS). European Hantavirus are usually associated with HFRS, and their geographical distribution mirrors the ecology of reservoir host species. Epidemiology of HFRS is well-studied in Western Europe, but data from Italy are fragmentary.

METHODS

We searched into two different databases (PubMed and EMBASE), focusing on studies reporting the prevalence of Hantaviruses in Italy. Data were extracted using a standardized assessment form, and results of the analyses were systematically reported, summarized and compared.

RESULTS

We identified a total of 18 articles, including 12 reports (total population: 5,336 subjects, 1981-2019) and 6 case reports (1984-2019). In total, 200 subjects exhibited some degree of seropositivity, with a pooled seroprevalence of 1.7% (95% confidence interval 0.7%-4.0%) in the general population. Higher occurrence was reported in selected subgroups, i.e. acute (28.7%, 95%CI 22.1-36.2) and chronic (6.6%, 95%CI 4.7-9.1) renal failure, forestry workers (3.0%, 95%CI 1.4-6.5, actual range 0.0 to 10.8%).

CONCLUSIONS

In the last decade, no human cases of hantavirus infection have been officially reported in Italy. However, our analysis stresses the actual occurrence of Hantavirus among general population and in selected population groups. Further studies on hantavirus infection rates in reservoir host species (rodents, shrews, and bats) and virus transmission to humans are needed to prevent outbreaks in the future.

Effectiveness Regarding Hantavirus Detection in Rodent Tissue Samples and Urine

The natural hosts of Orthohantaviruses are rodents, soricomorphs and bats, and it is well known that they may cause serious or even fatal diseases among humans worldwide. The virus is persistent among animals and it is shed via urine, saliva and feces throughout the entirety of their lives. We aim to identify the effectiveness of hantavirus detection in rodent tissue samples and urine originating from naturally infected rodents. Initially, animals were trapped at five distinct locations throughout the Transdanubian region in Hungary. Lung, liver, kidney and urine samples were obtained from 163 deceased animals. All organs and urine were tested using nested reverse transcription polymerase chain reaction (nRT-PCR). Furthermore, sera were examined for IgG antibodies against Dobrava-Belgrade virus (DOBV) and Puumala virus (PUUV) by Western blot assay. IgG antibodies against hantaviruses and/or nucleic acid were detected in 25 (15.3%) cases. Among Apodemus, Myodes, and Microtus rodent species, DOBV, PUUV and Tula virus (TULV) were clearly identified. Amid the PCR-positive samples, the nucleic acid of the viruses was detected most effectively in the kidney (100%), while only 55% of screened lung tissues were positive. Interestingly, only three out of 20 rodent urine samples were positive when tested using nRT-PCR. Moreover, five rodents were seropositive without detectable virus nucleic acid in any of the tested organs.

Comparison of VSV Pseudovirus and Focus Reduction Neutralization Assays for Measurement of Anti-Andes orthohantavirus Neutralizing Antibodies in Patient Samples

Andes orthohantavirus (ANDV) is the etiologic agent of hantavirus cardiopulmonary syndrome (HCPS), which has a case fatality rate around 35%, with no effective treatment or vaccine available. ANDV neutralizing antibody (NAb) measurements are important for the evaluation of the immune response following infection, vaccination, or passive administration of investigational monoclonal or polyclonal antibodies. The standard assay for NAb measurement is a focus reduction neutralization test (FRNT) featuring live ANDV and must be completed under biosafety level (BSL)-3 conditions. In this study, we compared neutralization assays featuring infectious ANDV or vesicular stomatitis virus (VSV) pseudovirions decorated with ANDV glycoproteins for their ability to measure anti-ANDV NAbs from patient samples. Our studies demonstrate that VSV pseudovirions effectively measure NAb from clinical samples and have greater sensitivity compared to FRNT with live ANDV. Importantly, the pseudovirus assay requires less labor and sample materials and can be conducted at BSL-2.

Analytical Performance of the RIDASCREEN® Hantavirus Puumala IgG/IgM ELISA Assay

The National Reference Center for Hantavirus in Belgium is currently using the Hantavirus IgM/IgG ELISA Progen kit (Heidelberg, Germany) for the detection of the most prevalent Hantavirus in Western Europe, Puumala virus (PUUV). Two commercially available PUUV kits were compared: Progen and RIDASCREEN^® Hantavirus Puumala IgM/IgG ELISA assay (Darmstadt, Germany). Methods: The sensitivity was evaluated with a panel of 68 samples from patients with an acute infection (n = 44) or a past infection (n = 24). Specificity was evaluated with a panel of 62 samples from patients with potentially false borderline results (n = 7) (no seroconversion), seronegative samples (n = 25) and potentially cross reacting samples (n = 30). Discordances were resolved by immunoblot. Substantial agreement was calculated using Cohen kappa coefficient. Results: The RIDASCREEN^® kit showed a higher specificity (IgM: 94.3%; IgG: 94.4%) than the Progen kit (IgM: 77.0% IgG: 93.0%). The sensitivity for IgM ELISA was 100% for both assays. IgG sensitivity was, respectively, 98.3% and 100% for Progen and RIDASCREEN^®. A Cohen kappa coefficient of 0.76 and 0.90 was found between Puumala IgM and IgG, respectively. Conclusions: This study showed a higher specificity for the RIDASCREEN^® kit than the Progen kit, while the sensitivity was as good as for the Progen kit.

Suggestive Serological Evidence of Infection with Shrew-Borne Imjin Virus (Hantaviridae) in Humans

The pathogenicity of the shrew-borne Imjin virus (MJNV) is unknown. The objective of our study was to find serological evidence of MJNV infection in humans. Partial MJNV nucleocapsid protein (NP) was cloned and expressed as an antigen for double-antigen sandwich ELISA, IgM capture ELISA, and dot blot to detect MJNV specific antibodies in hemorrhagic fever with renal syndrome (HFRS) patients’ and healthy persons’ sera from endemic areas in China. The purified recombinant NP reacted with neither the 90 healthy individuals’ sera from non-endemic areas of MJNV nor the 100 antisera to HFRS-causing virus, indicating that the MJNV NP had no cross-reaction with normal human sera and HFRS-causing viral antibodies. As determined by screening ELISA and dot blot analysis, IgG antibodies against MJNV NP were detected in sera from two of 385 healthy individuals from MJNV-endemic areas, suggesting infection with MJNV or MJNV-like thottimvirus. Based on the suggestive evidence, healthcare workers should be alert to febrile diseases occurring among individuals with exposure to shrew-infested habitats.

Fast, Sensitive and Specific Detection of Thailand orthohantavirus and its Variants Using One-Step Real-Time Reverse-Transcription Polymerase Chain Reaction Assay

Genetic variants of Thailand orthohantavirus (THAIV) have been recently reported from rodents in South-East Asia and in islands from the South-West part of the Indian Ocean. In order to detect THAIV and its variants, we developed a sensitive and specific real-time RT-PCR targeting the S segment. Our assay was developed in two different RT-PCR systems that gave similar results in terms of sensitivity. Moreover, our results demonstrated a specificity of 100%.

Exposure to Hantavirus is a Risk Factor Associated with Kidney Diseases in Sri Lanka: A Cross Sectional Study

Chronic kidney disease of unknown etiology (CKDu) imposes a substantial burden on public health in Sri Lankan agricultural communities. High seroprevalences of hantavirus have been reported in CKDu patients in several locations of Sri Lanka. We carried out a cross-sectional study followed by an unmatched case-control comparison in two geographically distinct areas of Sri Lanka, Girandurukotte (CKDu endemic) and Kandy (CKDu non-endemic) to determine whether exposure to hantaviruses is a potential risk factor in patients with kidney disease. An indirect immunofluorescent antibody assay using two antigens, Thailand orthohantavirus-infected and recombinant N protein-expressing Vero E6 cells, were used for serodiagnosis. Participants' demographic and other socio-economic data were collected through a structured questionnaire. Fifty kidney disease patients and 270 controls from Kandy and 104 kidney disease patients and 242 controls from Girandurukotte were examined. Seropositivities were 50% and 17.4% in kidney patients and controls, respectively, in Girandurukotte, and they were 18% and 7% in Kandy. The odds of exposure to hantaviruses were higher for kidney disease patients than for controls in both Girandurukotte (OR:3.66, 95% CI:2.01 to 6.64) and Kandy (OR:2.64, 95% CI:1.07 to 6.54) in binary logistic regression models. According to statistical analysis, individuals exposed to hantaviruses had a higher risk of developing renal impairment. Therefore, hantavirus infection might be an important risk factor for development of kidney disease in Sri Lanka.

Infection with New York Orthohantavirus and Associated Respiratory Failure and Multiple Cerebral Complications

We report a case of infection with New York orthohantavirus in a woman who showed renal impairment and hemorrhage, complicated by hydrocephalus, in Long Island, New York, USA. Phylogenetic analysis showed that this virus was genetically similar to a New York orthohantavirus isolated in the same region during 1993.

Assessing the Dynamics and Complexity of Disease Pathogenicity Using 4-Dimensional Immunological Data

Investigating disease pathogenesis and personalized prognostics are major biomedical needs. Because patients sharing the same diagnosis can experience different outcomes, such as survival or death, physicians need new personalized tools, including those that rapidly differentiate several inflammatory phases. To address these topics, a pattern recognition-based method (PRM) that follows an inverse problem approach was designed to assess, in <10 min, eight concepts: synergy, pleiotropy, complexity, dynamics, ambiguity, circularity, personalized outcomes, and explanatory prognostics (pathogenesis). By creating thousands of secondary combinations derived from blood leukocyte data, the PRM measures synergic, pleiotropic, complex and dynamic data interactions, which provide personalized prognostics while some undesirable features-such as false results and the ambiguity associated with data circularity-are prevented. Here, this method is compared to Principal Component Analysis (PCA) and evaluated with data collected from hantavirus-infected humans and birds that appeared to be healthy. When human data were examined, the PRM predicted 96.9 % of all surviving patients while PCA did not distinguish outcomes. Demonstrating applications in personalized prognosis, eight PRM data structures sufficed to identify all but one of the survivors. Dynamic data patterns also distinguished survivors from non-survivors, as well as one subset of non-survivors, which exhibited chronic inflammation. When the PRM explored avian data, it differentiated immune profiles consistent with no, early, or late inflammation. Yet, PCA did not recognize patterns in avian data. Findings support the notion that immune responses, while variable, are rather deterministic: a low number of complex and dynamic data combinations may be enough to, rapidly, unmask conditions that are neither directly observable nor reliably forecasted.

[Fulminant acute kidney injury after cholecystectomy in a 45-year-old female patient]

A cholecystectomy was carried out on a 45-year-old female patient with fever, myalgia and right upper abdominal pain because of a suspected cholecystitis. Postoperatively acute kidney injury occurred. A comprehensive medical history taken later revealed a presumed occupational contact to rodents. Serological testing detected a recent infection with Dobrava-Belgrade hantavirus. The kidney function normalized with supportive therapeutic measures. Hantavirus infection should be considered in the differential diagnosis of acute kidney injury combined with fever, myalgia and abdominal pain.

[Acute myopic shift call sign of hantavirus infection]

Acute myopic shift may be the first symptom of a hantavirus infection. In Belgium, lethal infections are rare, but this illness has to be ruled out in the emergency room. The refractive shift has not clearly been explained yet. The ancillary tests to describe this phenomenon are not always performed. This article may help on how to manage and how to explore this disease.

Distributional ecology of Andes hantavirus: a macroecological approach

BACKGROUND

Hantavirus pulmonary syndrome (HPS) is an infection endemic in Chile and Argentina, caused by Andes hantavirus (ANDV). The rodent Oligoryzomys longicaudatus is suggested as the main reservoir, although several other species of Sigmodontinae are known hosts of ANDV. Here, we explore potential ANDV transmission risk to humans in southern South America, based on eco-epidemiological associations among: six rodent host species, seropositive rodents, and human HPS cases.

METHODS

We used ecological niche modeling and macroecological approaches to determine potential geographic distributions and assess environmental similarity among rodents and human HPS cases.

RESULTS

Highest numbers of rodent species (five) were in Chile between 35° and 41°S latitude. Background similarity tests showed niche similarity in 14 of the 56 possible comparisons: similarity between human HPS cases and the background of all species and seropositive rodents was supported (except for Abrothrix sanborni). Of interest among the results is the likely role of O. longicaudatus, Loxodontomys micropus, Abrothrix olivaceus, and Abrothrix longipilis in HPS transmission to humans.

CONCLUSIONS

Our results support a role of rodent species' distributions as a risk factor for human HPS at coarse scales, and suggest that the role of the main reservoir (O. longicaudatus) may be supported by the broader rodent host community in some areas.

[Hantavirus causing fatal haemorrhagic fever in the Czech Republic]

Hantaviruses are RNA viruses of the family Bunyaviridae. Their hosts are mammals of the orders rodents (voles, rats, mice), insectivores (shrews, moles), and chiroptera (bats). Hantaviruses are present in many areas of Europe, the Americas, Asia, and Africa. In the Czech Republic, the occurrence of five species of hantaviruses has been reported (Dobrava/Belgrade, Puumala, Tula, Seewis, and Asikkala), with the first three of them causing human diseases. Although the course of hantavirus infections can be very serious, there is a low awareness of these diseases, even among health professionals, and hantavirus is often not considered in the diagnosis. A case history is reported of a patient who developed hantavirus haemorrhagic fever with renal syndrome (HFRS) with fatal outcome. The patient presented with typical clinical signs, but the correct diagnosis was only made at post mortem.

Acute-onset chronic inflammatory demyelinating polyneuropathy in hantavirus and hepatitis B virus coinfection: A case report

INTRODUCTION

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an acquired autoimmune disorder with progressive weakness. Acute-onset CIDP resembles Guillain-Barre syndrome (GBS), a rapidly progressive disorder, and follows a chronic course. To our knowledge, no case of acute-onset CIDP in hantavirus and hepatitis B virus (HBV) coinfection has been reported previously.

CLINICAL FINDINGS

We report a case of acute-onset CIDP that was initially diagnosed as GBS.

DIAGNOSES

A 44-year-old male logger complained of acute quadriplegia and dyspnea. Mechanical ventilation was initiated. He was an HBV carrier with mild elevation of hepatic enzyme, and positive for hantavirus antibody. He was diagnosed with GBS and immunoglobulin therapy was administered.

INTERVENTIONS

After 8 months, quadriplegia and hypesthesia recurred. Immunoglobulin therapy at this time had no effect, but steroid therapy had some effect.

OUTCOMES

A diagnosis of CIDP was made. After 2 months, severe extremity pain and dyspnea developed again, and steroid pulse therapy was initiated.

CONCLUSION

Besides GBS, acute-onset CIDP can occur with hantavirus and HBV coinfection. Patients with this coinfection in whom GBS has been initially diagnosed should be followed up for a long time, because of the possibility of relapse or deterioration, and acute-onset CIDP should always be considered.

A non-fatal case of hantavirus cardiopulmonary syndrome imported into the UK (ex Panama), July 2014

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Detection of hantavirus cardiopulmonary syndrome imported into Europe.

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Additional evidence that Choclo hantavirus is currently circulating and causing human disease in Panama.

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Novel diagnostic and sequencing assays for identifying cases of Choclo hantavirus infection.

Hantavirus infections among overnight visitors to Yosemite National Park, California, USA, 2012

TOC summary: A rare hantavirus outbreak reaffirms the need for control of deer mice and public awareness of the risks posed by contact with them.

In summer 2012, an outbreak of hantavirus infections occurred among overnight visitors to Yosemite National Park in California, USA. An investigation encompassing clinical, epidemiologic, laboratory, and environmental factors identified 10 cases among residents of 3 states. Eight case-patients experienced hantavirus pulmonary syndrome, of whom 5 required intensive care with ventilatory support and 3 died. Staying overnight in a signature tent cabin (9 case-patients) was significantly associated with becoming infected with hantavirus (p<0.001). Rodent nests and tunnels were observed in the foam insulation of the cabin walls. Rodent trapping in the implicated area resulted in high trap success rate (51%), and antibodies reactive to Sin Nombre virus were detected in 10 (14%) of 73 captured deer mice. All signature tent cabins were closed and subsequently dismantled. Continuous public awareness and rodent control and exclusion are key measures in minimizing the risk for hantavirus infection in areas inhabited by deer mice.

[Acute kidney injury caused by hantavirus in the Netherlands]

Although unusual in the Netherlands, acute kidney injury is sometimes caused by infection with Hantavirus, a zoonosis transmitted by rodents. Hantavirus infections can cause a syndrome known as 'haemorrhagic fever with renal syndrome', characterized by fever, acute kidney injury and thrombocytopenia. Recovery is spontaneous and treatment is mostly supportive. We describe two cases of otherwise healthy men presenting with fever and acute kidney injury. Laboratory tests revealed raised inflammatory parameters and thrombocytopenia. Urine analysis revealed proteinuria, microscopic haematuria and cell casts. Despite treatment with fluids, renal function declined and oliguria and fluid retention developed in one patient. Dialysis could be avoided, with spontaneous recovery of renal function in both cases. Serological testing revealed acute Hantavirus infection. Acute kidney injury caused by Hantavirus infections is rare in the Netherlands, but should be suspected in any patient presenting with renal failure and a history of viral infection.

Tula hantavirus infection in immunocompromised host, Czech Republic

We report molecular evidence of Tula hantavirus as an etiologic agent of pulmonary-renal syndrome in an immunocompromised patient. Acute hantavirus infection was confirmed by using serologic and molecular methods. Sequencing revealed Tula virus genome RNA in the patient’s blood. This case shows that Tula virus can cause serious disease in humans.

Identification of hantavirus infection by Western blot assay and TaqMan PCR in patients hospitalized with acute kidney injury

Hantaviruses, one of the causative agents of viral hemorrhagic fevers, represent a considerable healthcare threat. In Hungary, Dobrava-Belgrade virus (DOBV) and Puumala virus (PUUV) are the main circulating hantavirus species, responsible for the clinical picture known as hemorrhagic fever with renal syndrome, a disease that may be accompanied by acute kidney injury (AKI), requiring hospitalization with occasionally prolonged recovery phase. A total of 20 patient sera were collected over a 2-year period from persons hospitalized with AKI, displaying clinical signs and laboratory findings directly suggestive for hantavirus infection. Samples were tested using an immunoblot assay, based on complete viral nucleocapsid proteins to detect patients' IgM and IgG antibodies against DOBV and PUUV. In parallel, all specimens were also tested by 1-step real-time TaqMan reverse-transcriptase polymerase chain reaction to confirm infection and to determine the causative hantavirus genotype. We present here the first Hungarian clinical study spanning across 2 years and dedicated specifically to assess acute kidney injuries, in the context of hantavirus prevalence.

The continued emergence of hantaviruses: isolation of a Seoul virus implicated in human disease, United Kingdom, October 2012

Following a suspected case of hantavirus in a patientsuffering from acute kidney injury, rodents fromthe patient’s property in Yorkshire and the Humber,United Kingdom (UK) were screened for hantaviruses.Hantavirus RNA was detected via RT-PCR in two Rattusnorvegicus. Complete sequencing and phylogeneticanalysis established the virus as a Seoul hantavirus,which we have provisionally designated as strainHumber. This is the first hantavirus isolated from wildrodents in the UK and confirms the presence of a pathogenicSeoul virus in Europe.

[Hantavirus infection as the cause of haemorrhagic fever with renal syndrome]

Hantavirus is an RNA virus that can cause potentially fatal pulmonary and renal diseases in humans. Infections with Hantaviruses occur through inhalation of aerosol from rodent faeces, urine or saliva. The predominant virus type in Denmark is the Puumala virus, which causes the mildest form of haemorrhagic fever with renal syndrome, the so-called nephropathia epidemica (NE) with good prognosis (mortality 0.1-0.4%). The incidence of Hantavirus-infection in Denmark is about ten cases a year. The diagnosis of Hantavirus-infection is based on serology and/or polymerase chain reaction in blood or urine.

[Hantavirus diseases]

Hantaviruses are emerging viruses that cause persistent chronic infections in their small mammal hosts. When these viruses are transmitted to humans, they can cause two clinical syndromes, hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS). The understanding of the epidemiology, pathogenesis and natural history of these viruses has improved in recent years. The number of reported hantavirus infections is increasing worldwide and new hantaviruses are being discovered in many countries, so they now represent a public health problem of global concern. It is believed that hantavirus infections might be underestimated due to the frequently asymptomatic and nonspecific mild infections they cause as well as the lack of simple standardized diagnostic laboratory methods. In this review the current concepts regarding the epidemiology, ecology, clinical presentation, pathogenesis, diagnosis, and treatment of the infections associated with these emerging human pathogens are presented.

Second external quality assurance study for the serological diagnosis of hantaviruses in Europe

Hantaviruses are endemic throughout the world and hosted by rodents and insectivores. Two human zoonoses, hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS), are caused by hantaviruses and case fatality rates have reached 12% for HFRS and 50% for HPS in some outbreaks. Symptomatic hantavirus infections in Europe are summarised as HFRS mainly due to Puumala, Dobrava-Belgrade and Saaremaa virus. While HFRS has an overall low incidence in Europe, the number of cases varies from 100 per year in all Eastern and Southern Europe up to 1,000 per year only in Finland. To assess the quality of hantavirus diagnostics, the European Network for the Diagnostics of “Imported” Viral Diseases (ENIVD) organised a first external quality assurance (EQA) in 2002. The purpose of this second EQA study is to collect updated information on the efficiency and accurateness of hantavirus serological methods applied by expert laboratories. A serum panel of 14 samples was sent to 28 participants in Europe of which 27 sent results. Performance in hantavirus diagnosis varied not only on the method used but also on the laboratories and the subclass of antibodies tested. Commercial and in-house assays performed almost equally. Enzyme immunoassays were mainly used but did not show the best performances while immunoblot assays were the less employed and showed overall better performances. IgM antibodies were not detected in 61% of the positive IgM samples and IgM detection was not performed by 7% of the laboratories indicating a risk of overlooking acute infections in patients. Uneven performances using the same method is indicating that there is still a need for improving testing conditions and standardizing protocols.

Hantaviruses are endemic throughout the world and naturally hosted by rodents. The vast majority of human hantavirus infections are asymptomatic. In Europe, symptomatic hantavirus infections are summarised as hemorrhagic fever with renal syndrome (HFRS) mainly due to Puumala, Dobrava-Belgrade and Saaremaa virus. HFRS can cause fever, headache, and flank and abdominal pain. Moreover, renal dysfunction can lead to acute renal failure. Despite numerous research efforts, there is still no safe and effective vaccine or specific antiviral treatment against hantavirus infections. In this context, an accurate diagnosis as well as a reliable surveillance of hantavirus infections is essential. The diagnostics of hantavirus infections are based on serology using in-house or commercial assays. To assess the quality of hantavirus diagnostics, the European Network for the Diagnostics of “Imported” Viral Diseases organised a first external quality assurance (EQA) in 2002. In this publication we describe a second EQA study launched in 2011 with the objective to collect updated information on the efficiency and accurateness of hantavirus serological methods applied by expert laboratories. The study shows uneven performances indicating that there is still a need for improving testing conditions and standardizing protocols.

[A study of immunoassay by using quantum dots to detect Hantavirus infection]

OBJECTIVE

To develop a new method to detect anti-Hantavirus IgG antibodies (HV IgG) based on quantum dots (QDs) and indirect immune technique.

METHODS

The carbodiimide crosslinking method was used to couple protein G and goat antihuman IgG on the surface of water-solubility QDs. The coverglass covered HV antigen was used as carrier, and QDs-PG-IgG conjugates was used as labeled second antibody to detect the HV-IgG in the serum samples. The detecting conditions were optimized.

RESULTS

The optimum reaction time, pH and goat antihuman IgG concentration for conjugating the QDs with goat antihuman IgG were 6.0, 2h, and 20 microg/ml, respectively. The optimum working dilution of QDs-PG-IgG conjugates was 1: 200. The detection limit of the serum samples was about 1: 1280 dilution.

CONCLUSION

The method established in this study has been demonstrated to be a specific, sensitive, rapid test for detecting HV antibodies, laying the foundation of single molecule detection. The anti-fluorescence quenching ability of this method was significant improved.

Rodent-borne hantaviruses in Cambodia, Lao PDR, and Thailand

In order to evaluate the circulation of hantaviruses present in southeast Asia, a large scale survey of small mammal species was carried out at seven main sites in the region (Cambodia, Lao People's Democratic Republic, and Thailand). Small scale opportunistic trapping was also performed at an eighth site (Cambodia). Using a standard IFA test, IgG antibodies reacting to Hantaan virus antigens were detected at six sites. Antibody prevalence at each site varied from 0 to 5.6% with antibodies detected in several rodent species (Bandicota indica, B. savilei, Maxomys surifer, Mus caroli, M. cookii, Rattus exulans, R. nitidius, R. norvegicus, and R. tanezumi). When site seroprevalence was compared with site species richness, seropositive animals were found more frequently at sites with lower species richness. In order to confirm which hantavirus species were present, a subset of samples was also subjected to RT-PCR. Hantaviral RNA was detected at a single site from each country. Sequencing confirmed the presence of two hantavirus species, Thailand and Seoul viruses, including one sample (from Lao PDR) representing a highly divergent strain of Seoul virus. This is the first molecular evidence of hantavirus in Lao PDR and the first reported L segment sequence data for Thailand virus.

Characterization of monoclonal antibodies against hantavirus nucleocapsid protein and their use for immunohistochemistry on rodent and human samples

Monoclonal antibodies are important tools for various applications in hantavirus diagnostics. Recently, we generated Puumala virus (PUUV)-reactive monoclonal antibodies (mAbs) by immunisation of mice with chimeric polyomavirus-derived virus-like particles (VLPs) harbouring the 120-amino-acid-long amino-terminal region of the PUUV nucleocapsid (N) protein. Here, we describe the generation of two mAbs by co-immunisation of mice with hexahistidine-tagged full-length N proteins of Sin Nombre virus (SNV) and Andes virus (ANDV), their characterization by different immunoassays and comparison with the previously generated mAbs raised against a segment of PUUV N protein inserted into VLPs. All of the mAbs reacted strongly in ELISA and western blot tests with the antigens used for immunization and cross-reacted to varying extents with N proteins of other hantaviruses. All mAbs raised against a segment of the PUUV N protein presented on chimeric VLPs and both mAbs raised against the full-length AND/SNV N protein reacted with Vero cells infected with different hantaviruses. The reactivity of mAbs with native viral nucleocapsids was also confirmed by their reactivity in immunohistochemistry assays with kidney tissue specimens from experimentally SNV-infected rodents and human heart tissue specimens from hantavirus cardiopulmonary syndrome patients. Therefore, the described mAbs represent useful tools for the immunodetection of hantavirus infection.

Non-human primates in outdoor enclosures: risk for infection with rodent-borne hantaviruses

Different species of non-human primates have been exploited as animal disease models for human hantavirus infections. To study the potential risk of natural hantavirus infection of non-human primates, we investigated serum samples from non-human primates of three species living in outdoor enclosures of the German Primate Center (GPC), Göttingen, located in a hantavirus endemic region of central Germany. For that purpose we used serological assays based on recombinant antigens of the bank vole (Myodes glareolus) transmitted Puumala virus (PUUV) and the common and field vole (Microtus arvalis, Microtus agrestis) associated Tula virus (TULV) which are both broadly geographically distributed in Germany. In 24 out of 251 (9.6%) monkey sera collected in 2006 PUUV- and/or TULV-reactive immunoglobulin G (IgG) antibodies were detected. Investigation of follow-up sera from 13 animals confirmed for two animals a seroconversion due to hantavirus exposure at the GPC. To prove the origin of the infection, wild rodents from the surrounding regions were analyzed by hantavirus-specific reverse transcriptase-PCR analysis. In 6 of the 73 investigated bank voles and 3 of the 19 investigated Microtus spp. PUUV- and TULV-specific nucleic acid sequences, respectively, were detected. In conclusion, our investigations demonstrate for the first time natural infections of non-human primates in outdoor enclosures in Germany. These findings highlight the importance of hantavirus surveillance in those primate housings and corresponding preventive measures against wild rodents, particularly in hantavirus endemic regions.

[Thrombocytopenia and acute kidney injury]

A 31-year old man is addressed to the emergency department for fever, abdominal pain and vomiting. Laboratory tests reveal an inflammatory syndrome, thrombocytopenia, acute kidney injury associated with major proteinuria (more than 3 g/24 h). Evaluation will conclude to an acute interstitial nephritis and the serology is positive for Hantavirus. This clinical case illustrates differential diagnosis of acute renal failure and reminds the theory of hemorrhagic fever with renal syndrome : usual clinical presentation is "flu"-like symptoms, thrombocytopenia and acute renal failure. Hantavirus is endemic in some area in Europe and in Belgium. This clinical presentation should suggest the diagnosis if the patient has stayed in an endemic area.

[Serological characteristics of hantaviruses from clinical specimens analyzed in 1998-2008 in the Department of Virology, Public Health Institute, Ostrava]

In 1998 - 2008, serum samples from 464 patients, predominantly residents of the Moravia-Silesian Region, were examined in the Department of Virology, Public Health Institute in Ostrava, using Enzyme-Linked ImmunoSorbent Assay (ELISA) for the detection of specific anti-hantavirus antibodies. Seropositivity was ascertained in 41 persons (8.8%). More patients tested seropositive against Hantaan virus (24, i.e. 58.5%) than against Puumala virus (13, i.e. 31.7%). Four persons were reactive against both antigens. Clinical symptoms corresponding to hantavirus infection were observed in 19 seropositive patients. Fifteen of them had antibodies reactive with Hantaan virus antigen (cross-reactive with anti-Dobrava virus), 3 patients had antibodies against Puumala virus and 1 patient had both types of antibodies. Clinical data on the other seropositive persons were lacking. The higher rate of Dobrava virus infections in the Moravian-Silesian Region seems to be associated, among others, with the geographic distribution of striped field mouse (Apodemus agrarius) which is the main reservoir of Dobrava virus in Central Europe.

Hanta virus infection during dengue virus infection outbreak in Indonesia

AIM

To investigate which recent infection could have caused the present dengue-like symptoms, in adult patients clinically fulfilling the WHO criteria for dengue, in which serologically were not confirmed for dengue virus infections.

METHODS

Prospective study. During an outbreak of dengue (between May 1995 and May 1996) 118 consecutive adults (>13 years) suspected by the WHO 1997 case definition of DF or DHF were investigated. Patients were examined for history of illness, physical and laboratory findings consisting of full blood counts, prothrombin time (PT), activated partial thromboplastin time (aPTT), liver function (bilirubin, ASAT, ALAT), renal function (creatinine), and serological assays included dengue, hantavirus, chikungunya, R. typhi, R. tsutsugamuchi, rubella virus, influenza A virus, and leptospira.

RESULTS

In 58 of the total 118 patients, recent dengue virus infection was serologically confirmed. In 20 of the remaining 60 patients, we found serological evidence of another recent infection: hantavirus (5), chikungunya virus (2), R. typhi (5), R. tsutsugamuchi (2), rubella virus (3), influenza A virus (1), and leptospira (2). No evidence for recent infection with any of the mentioned agents was detected in the remaining 40 specimens.

CONCLUSION

We conclude that based on clinical characteristics alone, it is not easy to diagnose dengue. Specific laboratory tests to differentiate dengue from other febrile illnesses are needed. Among these, in Indonesia hantavirus infection should be considered as well.

Situation of hantavirus infections and haemorrhagic fever with renal syndrome in European countries as of December 2006

Hantavirus infections are widely distributed in Europe with the exception of the far north and the Mediterranean regions. The underlying causes of varying epidemiological patterns differ among regions: in western and central Europe epidemics of haemorrhagic fever with renal syndrome (HFRS) caused by hantavirus infections follow mast years with increased seed production by oak and beech trees followed by increased rodent reproduction. In the northern regions, hantavirus infections and HFRS epidemics occur in three to four year cycles and are thought to be driven by prey - predator interactions. Hantavirus infections and HFRS seem to be on the increase in Europe, partly because of better diagnostics, partly perhaps due to environmental changes. Unfortunately, hantavirus infections are still heavily under-diagnosed in many European countries. Here we report the results of a survey conducted in 2007 amongst the member laboratories of the European Network for diagnostics of Imported Viral Diseases (ENIVD).

[Hantavirus infections]

Hantaviruses are enveloped single-stranded ribonucleic acid (RNA) viruses that belong to the family Bunyaviridae. They are widely distributed and maintained in populations of specific insectivores or rodent host species (mice or rats). In their natural host, hantaviruses develop persistent and asymptomatic infections with lifelong virus shedding in excreta. Transmission to humans occurs via direct contact with faeces, urine and saliva of infected rodents, in particular by inhaling virus contaminated aerosol. There are a variety of virus types that occur in different geographic areas, dependent on the natural distribution of the host. Unlike asymptomatic infection in rodents, several types of hantaviruses cause acute febrile diseases in humans, known as haemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). In Germany, human hantavirus infections frequently represent as nephropathia epidemica (NE), a generally mild HFRS form with influenza-like symptoms such as fever, myalgia, headache and gastrointestinal disorders. Kidney failure, a characteristic sign of hantavirus infections, is also common. German NE cases are primarily caused by Puumala viruses (PUUV) which naturally persist in the bank vole, a mouse species that is widely distributed in the whole area of Germany. During 2005 and 2007, in several regions of Southern and Western Germany there was an unexpected increase in PUUV-associated NE cases. Currently, 1687 symptomatic hantavirus infections have been reported until the end of 2007, which is the highest number of hantavirus diseases in Germany since the introduction of the German infection protective law (Deutsches Infektionsschutzgesetz) in 2001. Treatment of hantavirus infections is mainly supportive and involves intensive medical care. A specific antiviral therapy with ribavirin has been shown to be successful for treatment of HFRS patients in the early stage of disease. In Germany, there is no licensed vaccine applicable for the prevention of hantavirus diseases. Anti-infectious measures are, therefore, regarded to be the most effective strategy to prevent illnesses due to these emerging RNA viruses.