Hantavirus Disease Cluster Caused by Seoul Virus, Germany.

A cluster of 3 persons in Germany experienced hantavirus disease with renal insufficiency. Reverse transcription PCR-based genotyping revealed infection by Seoul hantavirus transmitted from pet rats. Seoul virus could be responsible for disease clusters in Europe, and infected pet rats should be considered a health threat.

Tula Virus as Causative Agent of Hantavirus Disease in Immunocompetent Person, Germany.

We report molecular evidence of Tula virus infection in an immunocompetent patient from Germany who had typical signs of hantavirus disease. Accumulating evidence indicates that Tula virus infection, although often considered nonpathogenic, represents a threat to human health.

Macropinocytosis and Clathrin-Dependent Endocytosis Play Pivotal Roles for the Infectious Entry of Puumala Virus.

Viruses from the family Hantaviridae are encountered as emerging pathogens causing two life-threatening human zoonoses: hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS), with case fatality rates of up to 50%. Here, we comprehensively investigated entry of the Old World hantavirus Puumala virus (PUUV) into mammalian cells, showing that upon treatment with pharmacological inhibitors of macropinocytosis and clathrin-mediated endocytosis, PUUV infections are greatly reduced. We demonstrate that the inhibitors did not interfere with viral replication and that RNA interference, targeting cellular mediators of macropinocytosis, decreases PUUV infection levels significantly. Moreover, we established lipophilic tracer staining of PUUV particles and show colocalization of stained virions and markers of macropinosomes. Finally, we report a significant increase in the fluid-phase uptake of cells infected with PUUV, indicative of a virus-triggered promotion of macropinocytosis.IMPORTANCE The family Hantaviridae comprises a diverse group of virus species and is considered an emerging global public health threat. Individual hantavirus species differ considerably in terms of their pathogenicity but also in their cell biology and host-pathogen interactions. In this study, we focused on the most prevalent pathogenic hantavirus in Europe, Puumala virus (PUUV), and investigated the entry and internalization of PUUV into mammalian cells. We show that both clathrin-mediated endocytosis and macropinocytosis are cellular pathways exploited by the virus to establish productive infections and demonstrate that pharmacological inhibition of macropinocytosis or a targeted knockdown using RNA interference significantly reduced viral infections. We also found indications of an increase of macropinocytic uptake upon PUUV infection, suggesting that the virus triggers specific cellular mechanisms in order to stimulate its own internalization, thus facilitating infection.

Autochthonous Ratborne Seoul Virus Infection in Woman with Acute Kidney Injury.

Outside Asia, Seoul virus (SEOV) is an underestimated pathogen. In Germany, autochthonous SEOV-associated hantavirus disease has not been unequivocally diagnosed. We found clinical and molecular evidence for SEOV infection in a young woman; her pet rat was the source of infection.

Approaches to optimize therapeutic bacteriophage and bacteriophage-derived products to combat bacterial infections.

The emerging occurrence of antibiotic-resistant bacterial pathogens leads to a recollection of bacteriophage as antimicrobial therapeutics. This article presents a short overview of the clinical phage application including their use in military medicine and discusses the genotypic and phenotypic properties of a potential "ideal" therapeutic phage. We describe current efforts to engineer phage for their improved usability in pathogen treatment. In addition, phage can be applied for pathogen detection, selective drug delivery, vaccine development, or food and surface decontamination. Instead of viable phage, (engineered) phage-derived enzymes, such as polysaccharide depolymerases or peptidoglycan-degrading enzymes, are considered as promising therapeutic candidates. Finally, we briefly summarize the use of phage for the detection and treatment of "Category A priority pathogens".

Detection of possible spillover of a novel hantavirus in a Natal mastomys from Guinea.

To date, only two rodent-borne hantaviruses have been detected in sub-Saharan Africa. Here, we report the detection of a yet unknown hantavirus in a Natal mastomys (Mastomys natalensis) in Méliandou, Guinea, in 2014. The phylogenetic placement of this virus suggests that it might represent a cross-order spillover event from an unknown bat or eulipotyphlan host.

Hemorrhagic Fever with Renal Syndrome, Russia.

In Russia, 131,590 cases of hemorrhagic fever with renal syndrome caused by 6 different hantaviruses were reported during 2000-2017. Most cases, 98.4%, were reported in western Russia. The average case-fatality rate was 0.4%, and strong regional differences were seen, depending on the predominant virus type.

Classic paper: Are the chickenpox virus and the zoster virus identical?: HELMUT RUSKA.

As early as 1943, the German physician Helmut Ruska visualized the virus of varicella and zoster (at that time, he was not completely certain whether the virus was the same) by the newly developed electron microscope; he is regarded as the discoverer of this virus. Here, we present a translation of his classical paper into the English language. In our introduction and commentary to his paper, we discuss the significance of Helmut Ruska's work for the development of virology, his distinction between the varicella, zoster, and herpes virus group on one hand and poxviruses on the other, as well as the development of imaging techniques which have refined or substituted for electron microscopy of viruses and virus-infected cells.

Molecular and epidemiological characteristics of human Puumala and Dobrava-Belgrade hantavirus infections, Germany, 2001 to 2017.

IntroductionTwo hantavirus species, Puumala (PUUV) and Dobrava-Belgrade (DOBV) virus (genotype Kurkino), are endemic in Germany. Recent PUUV outbreaks raised questions concerning increasing frequency of outbreaks and expansion of PUUV endemic areas.AimsTo describe the epidemiology of human PUUV and DOBV infections in Germany.MethodsWe conducted an observational retrospective study analysing national hantavirus surveillance data notified to the national public health institute and hantavirus nucleotide sequences from patients collected at the national consultation laboratory between 2001 and 2017. Matching molecular sequences with surveillance data, we conducted epidemiological, phylogenetic and phylogeographic analyses.ResultsIn total, 12,148 cases of symptomatic hantavirus infection were notified 2001-17 (mean annual incidence: 0.87/100,000; range: 0.09-3.51). PUUV infections showed a highly variable space-time disease incidence pattern, causing large outbreaks every 2-3 years with peaks in early summer and up to 3,000 annually reported cases. Sex-specific differences in disease presentation were observed. Of 202 PUUV nucleotide sequences obtained from cases, 189 (93.6%) fall into well-supported phylogenetic clusters corresponding to different endemic areas in Germany. DOBV infections caused few, mostly sporadic cases in autumn and winter in the north and east of Germany.ConclusionsThe frequency of PUUV outbreaks increased between 2001 and 2017 but our data does not support the suggested expansion of endemic areas. The epidemiology of PUUV and DOBV-Kurkino infections differs in several aspects. Moreover, the latter are relatively rare and combining efforts and data of several countries to identify risk factors and develop specific recommendations for prevention could be worthwhile.

Importation of Human Seoul Virus Infection to Germany from Indonesia.

Seoul hantavirus-associated hemorrhagic fever with renal syndrome cases are rare outside Asia and have not yet been found in Germany. We report clinical and molecular evidence for a Seoul virus infection in a patient in Germany. The infection was most likely acquired during a stay in Sulawesi, Indonesia.

The nucleocapsid protein of hantaviruses: much more than a genome-wrapping protein.

The nucleocapsid (N) protein of hantaviruses represents an impressive example of a viral multifunctional protein. It encompasses properties as diverse as genome packaging, RNA chaperoning, intracellular protein transport, DNA degradation, intervention in host translation, and restricting host immune responses. These functions all rely on the capability of N to interact with RNA and other viral and cellular proteins. We have compiled data on the N protein of different hantavirus species together with information of the recently published three-dimensional structural data of the protein. The array of diverse functional activities accommodated in the hantaviral N protein goes far beyond to be a static structural protein and makes it an interesting target in the development of antiviral therapeutics.

Human Infections by Non-Rodent-Associated Hantaviruses in Africa.

Various hantaviruses have been discovered in unconventional hosts (shrews and bats) in Africa. Up to now, it was unknown whether these viruses pose a threat for human health. In this study, using newly established serological assays, we demonstrated evidence of shrew-borne hantavirus infections in humans from Côte d'Ivoire and Gabon.

Serum hepatitis B virus RNA levels as an early predictor of hepatitis B envelope antigen seroconversion during treatment with polymerase inhibitors.

UNLABELLED: Hepatitis B envelope antigen (HBeAg) seroconversion represents an endpoint of treatment of chronic hepatitis B virus (HBV) infections. We have studied whether levels of serum HBV RNA during polymerase inhibitor treatment might be helpful for predicting HBeAg seroconversion. HBV RNA levels were determined in serial serum samples from 62 patients with chronic HBV infection (50 HBeAg positive). Patients received antiviral treatment for a mean duration of 30 ± 15 (range, 4-64) months. A new rapid amplification of complimentary DNA-ends-based real-time polymerase chain reaction was established for quantitative analysis of polyadenylated full-length (fl) and truncated (tr) HBV RNA. HBV RNA, HBV DNA, and hepatitis B surface antigen (HBsAg) levels as well as presence of HBeAg and hepatitis B envelope antibody were measured at baseline, month 3, month 6, and subsequent time points. Fifteen patients who achieved HBeAg seroconversion after a mean duration of 19 ± 14 (range, 3-56) months of antiviral treatment showed a significantly stronger decline in mean HBV flRNA and trRNA levels from baseline to month 3 of 1.0 ± 1.4 (range, -1.6-3.4) and 2.1 ± 1.4 (range, 0-3.9) and to month 6 of 1.8 ± 1.4 (range, 0-4.6) and 3.1 ± 1.7 (range, 0-5.1) log10 copies/mL, respectively, in comparison to 35 HBeAg-positive patients without HBeAg seroconversion (P < 0.001 for months 3 and 6). A similar decline in HBV RNA levels was observed in HBeAg-negative patients. The decline of HBV RNA levels at months 3 and 6 of treatment was to be the strongest predictor of HBeAg seroconversion, when compared to levels of HBV DNA, HBsAg, alanine aminotransferase, and HBV genotype, age, and sex. CONCLUSION: Serum HBV RNA levels may serve as a novel tool for prediction of serological response during polymerase inhibitor treatment in HBeAg-positive patients.

High seroprevalence of antibodies against Kaposi's sarcoma-associated herpesvirus (KSHV) among HIV-1-infected children and adolescents in a non-endemic population.

Human herpesvirus-8 (HHV-8) is the etiological agent of Kaposi's sarcoma (KS), which primarily affects human immunodeficiency virus (HIV)-infected adults with advanced immunodeficiency. Currently, only limited prevalence data for HHV-8 infection in HIV-infected children living in non-endemic areas are available. This multicenter cross-sectional study was conducted in four university hospitals in Germany specializing in pediatric HIV care. Stored serum specimens obtained from 207 vertically HIV-1-infected children and adolescents were tested for antibodies against lytic and latent HHV-8 antigens. Logistic regression was used to assess independent risk factors associated with HHV-8 seropositivity. The overall HHV-8 seroprevalence was 24.6 % (n = 51/207) without significant differences related to sex, age, or ethnicity. In univariate analysis, HHV-8 seropositivity was significantly associated with a child having being born outside Germany, maternal origin from sub-Saharan Africa, a history of breastfeeding, CDC immunologic category 3, and deferred initiation of antiretroviral therapy (>24 months of age). In multivariate analysis, a child's birth outside Germany was the only significant risk factor for HHV-8 seropositivity (odds ratio 3.98; 95 % confidence interval 1.27-12.42). HHV-8-associated malignancies were uncommon; only one patient had a history of KS. Serum specimen of vertically HIV-infected children and adolescents living in Germany showed a high HHV-8 seroprevalence. These findings suggest that primary HHV-8 infection-a risk factor for KS and other HHV-8-associated malignancies-occurs early in life. Thus, management of perinatally HIV-infected children should include testing for HHV-8 coinfection and should consider future risks of HHV-8-associated malignancies.

Clinical characterization of two severe cases of hemorrhagic fever with renal syndrome (HFRS) caused by hantaviruses Puumala and Dobrava-Belgrade genotype Sochi.

BACKGROUND: Hantavirus disease belongs to the emerging infections. The clinical picture and severity of infections differ between hantavirus species and may even vary between hantavirus genotypes. The mechanisms that lead to the broad variance of severity in infected patients are not completely understood. Host- and virus-specific factors are considered. CASE PRESENTATION: We analyzed severe cases of hantavirus disease in two young women. The first case was caused by Puumala virus (PUUV) infection in Germany; the second case describes the infection with Dobrava-Belgrade virus (DOBV) in Russia. Symptoms, laboratory parameters and cytokine levels were analyzed and compared between the two patients. Serological and sequence analysis revealed that PUUV was the infecting agent for the German patient and the infection of the Russian patient was caused by Dobrava-Belgrade virus genotype Sochi (DOBV-Sochi). The symptoms in the initial phase of the diseases did not differ noticeably between both patients. However, deterioration of laboratory parameter values was prolonged and stronger in DOBV-Sochi than in PUUV infection. Circulating endothelial progenitor cells (cEPCs), known to be responsible for endothelial repair, were mobilized in both infections. Striking differences were observed in the temporal course and level of cytokine upregulation. Levels of angiopoietin-2 (Ang-2), vascular endothelial growth factor (VEGF), and stromal derived factor-1 (SDF-1α) were increased in both infections; but, sustained and more pronounced elevation was observed in DOBV-Sochi infection. CONCLUSIONS: Severe hantavirus disease caused by different hantavirus species did not differ in the general symptoms and clinical characteristics. However, we observed a prolonged clinical course and a late and enhanced mobilization of cytokines in DOBV-Sochi infection. The differences in cytokine deregulation may contribute to the observed variation in the clinical course.

Life-Threatening Sochi Virus Infections, Russia.

Sochi virus was recently identified as a new hantavirus genotype carried by the Black Sea field mouse, Apodemus ponticus. We evaluated 62 patients in Russia with Sochi virus infection. Most clinical cases were severe, and the case-fatality rate was as high as 14.5%.

Novel Arenavirus Isolates from Namaqua Rock Mice, Namibia, Southern Africa.

Arenaviruses are feared as agents that cause viral hemorrhagic fevers. We report the identification, isolation, and genetic characterization of 2 novel arenaviruses from Namaqua rock mice in Namibia. These findings extend knowledge of the distribution and diversity of arenaviruses in Africa.

Hantavirus-induced pathogenesis in mice with a humanized immune system.

Hantaviruses are emerging zoonotic pathogens that can cause severe disease in humans. Clinical observations suggest that human immune components contribute to hantavirus-induced pathology. To address this issue we generated mice with a humanized immune system. Hantavirus infection of these animals resulted in systemic infection associated with weight loss, decreased activity, ruffled fur and inflammatory infiltrates of lung tissue. Intriguingly, after infection, humanized mice harbouring human leukocyte antigen (HLA) class I-restricted human CD8+ T cells started to lose weight earlier (day 10) than HLA class I-negative humanized mice (day 15). Moreover, in these mice the number of human platelets dropped by 77 % whereas the number of murine platelets did not change, illustrating how differences between rodent and human haemato-lymphoid systems may contribute to disease development. To our knowledge this is the first description of a humanized mouse model of hantavirus infection, and our results indicate a role for human immune cells in hantaviral pathogenesis.

Evidence for novel hepaciviruses in rodents.

Hepatitis C virus (HCV) is among the most relevant causes of liver cirrhosis and hepatocellular carcinoma. Research is complicated by a lack of accessible small animal models. The systematic investigation of viruses of small mammals could guide efforts to establish such models, while providing insight into viral evolutionary biology. We have assembled the so-far largest collection of small-mammal samples from around the world, qualified to be screened for bloodborne viruses, including sera and organs from 4,770 rodents (41 species); and sera from 2,939 bats (51 species). Three highly divergent rodent hepacivirus clades were detected in 27 (1.8%) of 1,465 European bank voles (Myodes glareolus) and 10 (1.9%) of 518 South African four-striped mice (Rhabdomys pumilio). Bats showed anti-HCV immunoblot reactivities but no virus detection, although the genetic relatedness suggested by the serologic results should have enabled RNA detection using the broadly reactive PCR assays developed for this study. 210 horses and 858 cats and dogs were tested, yielding further horse-associated hepaciviruses but none in dogs or cats. The rodent viruses were equidistant to HCV, exceeding by far the diversity of HCV and the canine/equine hepaciviruses taken together. Five full genomes were sequenced, representing all viral lineages. Salient genome features and distance criteria supported classification of all viruses as hepaciviruses. Quantitative RT-PCR, RNA in-situ hybridisation, and histopathology suggested hepatic tropism with liver inflammation resembling hepatitis C. Recombinant serology for two distinct hepacivirus lineages in 97 bank voles identified seroprevalence rates of 8.3 and 12.4%, respectively. Antibodies in bank vole sera neither cross-reacted with HCV, nor the heterologous bank vole hepacivirus. Co-occurrence of RNA and antibodies was found in 3 of 57 PCR-positive bank vole sera (5.3%). Our data enable new hypotheses regarding HCV evolution and encourage efforts to develop rodent surrogate models for HCV.

Does proficiency testing improve the quality of hantavirus serodiagnostics? Experiences with INSTAND EQA schemes.

Hantavirus infections in Germany appear periodically with peak numbers every 2-3 years. The reported cases in the years 2007, 2010 and 2012 exceeded many times over those in the years in-between. In order to reveal faults of certain in vitro diagnostic assays (IVDs), to harmonize the performances of the individual assays and to improve the users' competence in interpreting the results, the National Consiliary Laboratory for Hantaviruses and INSTAND e.V. (Society for Promoting Quality Assurance in Medical Laboratories e.V.) established an external quality assessment (EQA) scheme for proficiency testing of hantavirus serodiagnostics. The first EQA scheme (pilot study) started in March 2009 with 58 participating laboratories from Germany and neighboring countries. Twice a year four serum samples were sent out to the participants to investigate whether the sample reflects an acute or past infection and to distinguish between infections with the hantavirus types Puumala virus (PUUV) and Dobrava-Belgrade virus (DOBV), both endemic in Central Europe. In addition, samples negative for anti-hantavirus antibodies were tested in order to examine the specificity of the IVDs applied in the participating laboratories. An increasing number of laboratories participated, with a maximum of 92 in March 2014. When summarizing in total 2592 test results, the laboratories reached an overall specificity of 96.7% and a sensitivity of 95% in their detection of a hantavirus infection. A correct distinction between acute and past infections was forwarded in 90-96% of replies of laboratories. Exact serotyping (PUUV vs. DOBV) of the infection was reported in 81-96% of replies with the lowest accuracy for past DOBV infections; cross-reactivities between diagnostic antigens of the two viruses as well as persistent IgM titers in humans may interfere with exact testing. The EQAs revealed acceptable results for the serodiagnostic of hantavirus infection including serotyping but further improvement is still needed.