Tatjana Avsic Zupanc

• University of Ljubljana

Severe coronavirus infections, including SARS-CoV-2, can cause neurological symptoms, but the underlying neurotropic mechanisms are unclear. Experiments with SARS-CoV-2 variants B.1.258.17, B.1.1.7, and BA.5.3.2 (termed wild-type, alpha and omicron, respectively) revealed that human astrocytes, not neurons, support viral proliferation. During the C...

Abstract Background: The Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne pathogen known to cause severe viral hemorrhagic fever. Aim: We aimed to evaluate the potential circulation of CCHFV in Corsica through a serosurvey, including anonymized residual sera (RS) and high-risk individuals exposed to animals and/or tick bites due to oc...

Objectives The emergence of mpox outbreaks in non-endemic areas, characterised by human-to-human transmission and unique clinical presentations, poses challenges in containment efforts. This study aimed to analyse the 2022 outbreak in Slovenia and characterise the country’s response to the outbreak. Methods A retrospective, observational study ana...

Among the various causes of rhomboencephalitis, Listeria monocytogenes infection is the most common. However, conventional microbiological methods often yield negative results, making diagnosis challenging and leading to extensive, often inconclusive, diagnostics. Advanced molecular techniques like metagenomic next-generation sequencing (mNGS) offe...

Introduction Caused by the tick-borne encephalitis virus (TBEV), tick-borne encephalitis (TBE) is a zoonotic disease that can cause severe neurological symptoms. Despite the availability of a vaccine, it remains a public health concern in Europe, with an increasing number of reported human cases and new hotspots of virus circulation, also in previo...

This prospective cohort study assessed the SARS-CoV-2 IgG and IgA Ab profiles at delivery and 42 d postpartum in unvaccinated SARS-CoV-2–positive pregnant women and determined the association with the timing and the clinical course of the infection. A total of 387 vaccine-naive women with confirmed SARS-CoV-2 infection during pregnancy were include...

Tick-borne encephalitis virus (TBEV) vaccine breakthrough (VBT) infections are not uncommon in endemic areas. The clinical and immunological outcomes have been poorly investigated. We assessed the magnitude and specificity of virus-specific antibody and T cell responses after TBE in previously vaccinated subjects and compared the results with those...

Background Paediatric patients with autoimmune rheumatic diseases (pARD) have a dysregulated immune system, so infections present a major threat to them. To prevent severe COVID-19 infections we aimed to vaccinate them as soon as possible. Studies have shown that the BNT162b2 vaccine is safe, effective, and immunogenic, however, in a short observat...

Background The concurrent circulation of SARS-CoV-2 with other respiratory viruses is unstoppable and represents a new diagnostic reality for clinicians and clinical microbiology laboratories. Multiplexed molecular testing on automated platforms that focus on the simultaneous detection of multiple respiratory viruses in a single tube is a useful ap...

The emergence and rapid spread of SARS-CoV-2 prompted the global community to identify innovative approaches to diagnose infection and sequence the viral genome because at several points in the pandemic positive case numbers exceeded the laboratory capacity to characterize sufficient samples to adequately respond to the spread of emerging variants....

Introduction Residents of long-term care facilities (LTCFs) are at high risk of morbidity and mortality due to COVID-19, especially when new variants of concern (VOC) emerge. To provide intradisciplinary data in order to tailor public health interventions during future epidemics, available epidemiologic and genomic data from Slovenian LTCFs during...

Nairoviridae is a family for negative-sense RNA viruses with genomes of about 17.2-21.1 kb. These viruses are maintained in and/or transmitted by arthropods among birds, reptiles and mammals. Norwaviruses and orthonairoviruses can cause febrile illness in humans. Several orthonairoviruses can infect mammals, causing mild, severe and sometimes, fata...

Purpose: Since some patients with tick-borne encephalitis (TBE) have pronounced myalgias, and since myositis is reported in Flavivirus diseases such as dengue, we performed systematic search for abnormalities of muscle enzymes in a group of patients in whom the presence of tick-borne encephalitis virus (TBEV) RNA in the first phase of the disease...

Tick-borne encephalitis virus (TBEV) infection may cause acute central nervous system inflammation varying in clinical manifestations and severity. A possible correlation of TBEV-specific antibody and cell-mediated immune responses, shortly after infection, with clinical manifestations, severity and long-term outcome has been poorly investigated. I...

Monkeypox virus (MPXV), originally endemic in West Africa (Clade II) and Central Africa (Clade I), has recently emerged worldwide and has reinforced the need for rapid and accurate MPXV diagnostics. This review presents and critically discusses the range of virological methods for laboratory diagnosis and characterization of MPXV as well as related...

Background The concurrent circulation of SARS-CoV-2 with other respiratory viruses is unstoppable and represents a new diagnostic reality for clinicians and clinical microbiology laboratories. Multiplexed molecular testing on automated platforms that focus on the simultaneous detection of multiple respiratory viruses in a single tube is a useful ap...

Introduction Tick-borne encephalitis (TBE) is an emerging vector-borne and food-borne disease caused by the tick-borne encephalitis virus (TBEV; Orthoflavivirus encephalitidis), with a distribution spanning the Eurasian continent. Despite its significant public health impact in various European regions, TBE remains largely underdiagnosed in Serbia...

In this article, we report on a rare case of acute respiratory distress syndrome (ARDS) caused by the Puumala orthohantavirus (PUUV), which is typically associated with hemorrhagic fever with renal syndrome (HFRS). This is the first documented case of PUUV-associated ARDS in Southeast Europe. The diagnosis was confirmed by serum RT-PCR and serology...

Background Rodent-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). Aim We wished to evaluate the perfo...

Introduction: Monkeypox virus (MPXV), typically endemic in West and Central Africa, has raised global concern due to the recent outbreak in several non-endemic countries with human-to-human transmission. Here we present a comprehensive analysis of MPXV genomes from Slovenia. Methods: Two real-time polymerase chain reaction (RT-PCR) assays for Or...

In April 2023, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. The phylum was expanded by one new family, 14 new genera, and 140 new species. Two genera and 538 species were renamed. One species was moved, and four were abolished...

Background Paediatric patients with autoimmune rheumatic diseases (pARD) are often immunocompromised because of the disease and/or the therapy they receive. At the beginning of COVID-19 pandemic there was a great concern about the possibility of severe SARS-CoV-2 infection in these patients. The best method of protection is vaccination, so as soon...

Tick-borne encephalitis (TBE) is a viral infection of the human central nervous system caused by the TBE virus (TBEV). The most effective protective measure against TBE is vaccination. Despite the highly immunogenic vaccine, cases of vaccine breakthroughs (VBTs) occur. One of the first targets of infection is dendritic cells (DC), which represent a...

Introduction: We demonstrate the nonlinear severity of symptoms of SARS-CoV-2 infection in the mother leading to fetal death after acute placental failure. Methods: Careful clinical evaluation, real-time RT-PCR molecular microbiologic testing, isolation of a viable virus, and autopsy with histologic results were used to investigate the possible...

Monkeypox virus was imported into Finland during late May-early June 2022. Intrahost viral genome variation in a sample from 1 patient comprised a major variant with 3 lineage B.1.3-specific mutations and a minor variant with ancestral B.1 nucleotides. Results suggest either ongoing APOBEC3 enzyme-mediated evolution or co-infection.

In March 2022, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. The phylum was expanded by two new families (bunyaviral Discoviridae and Tulasviridae), 41 new genera, and 98 new species. Three hundred forty-nine species were renam...

Astrocytes, an abundant type of glial cells, are the key cells providing homeostasis in the central nervous system. Due to their susceptibility to infection, combined with high resilience to virus-induced cell death, astrocytes are now considered one of the principal types of cells, responsible for virus retention and dissemination within the brain...

Background SARS-CoV-2 infection does not confer long immunity. However, studies suggest that prior infection is associated with lower risk of reinfection and milder outcomes of recurrent infections. The aims of this retrospective observational case-control study were to describe the clinical and molecular characteristics of genetically confirmed De...

We report early importations of monkeypox virus to Finland during late May - early June 2022. Intrahost viral genome variation in one sample comprised a major variant with three lineage B.1.3-specific mutations and a minor variant with ancestral B.1 nucleotides, suggesting either ongoing APOBEC3-mediated evolution or coinfection.

We report early importations of monkeypox virus to Finland during late May - early June 2022. Intrahost viral genome variation in one sample comprised a major variant with three lineage B.1.3-specific mutations and a minor variant with ancestral B.1 nucleotides, suggesting either ongoing APOBEC3-mediated evolution or coinfection.

Tularemia is a zoonosis caused by the highly invasive bacterium Francisella tularensis. It is transmitted to humans by direct contact with infected animals or by vectors, such as ticks, mosquitos, and flies. Even though it is well-known as a tick-borne disease, it is usually not immediately recognised after a tick bite. In Slovenia, tularemia is ra...

The clinical symptoms caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are nonspecific and can be associated with most other respiratory viruses that cause acute respiratory tract infections (ARI). Because the clinical differentiation of COVID-19 patients from those with other respiratory viruses is difficult, the evaluati...

The clinical presentation of tick-borne encephalitis virus (TBEV) infection varies from asymptomatic to severe meningoencephalitis or meningoencephalomyelitis. The TBEV subtype has been suggested as one of the most important risk factors for disease severity, but TBEV genetic characterization is difficult. Infection is usually diagnosed in the post...

Tick-borne encephalitis (TBE) usually has a biphasic course which begins with unspecific febrile illness, followed by central nervous system involvement. Because TBE is not yet suspected during the initial phase, knowledge of early TBE pathogenesis is incomplete. Herein we evaluated laboratory and immune findings in the initial and second (meningoe...

Crimean-Congo haemorrhagic fever virus (CCHFV) is the medically most important member of the rapidly expanding bunyaviral family Nairoviridae. Traditionally, CCHFV isolates have been assigned to six distinct genotypes. Here, the International Committee on Taxonomy of Viruses (ICTV) Nairoviridae Study Group outlines the reasons for the recent decisi...

Several professional societies advise against using real-time Reverse-Transcription PCR (rtRT-PCR) cycle threshold (Ct) values to guide clinical decisions. We comparatively assessed the variability of Ct values generated by six diagnostic approaches by testing serial dilutions of well-characterized isolates of 10 clinically most relevant SARS-CoV-2...

Erratum in Correction to Lancet Microbe 2021; published online Nov 16. https://doi.org/10.1016/S2666-5247(21)00211-1. [No authors listed] Lancet Microbe. 2022 Jan;3(1):e8. doi: 10.1016/S2666-5247(21)00325-6. Epub 2021 Nov 26. PMID: 34870252 Free PMC article.

Objectives: To estimate the incidence and describe the spectrum of inflammatory and autoimmune diseases linked to SARS-CoV-2 infection and COVID-19 vaccination in children from two neighbouring south central European countries. Methods: We performed a multi-centre prospective cohort study of children under 18 years diagnosed with inflammatory/au...

Information on febrile illness caused by tick-borne encephalitis virus (TBEV) without central nervous system involvement is limited. We characterized 98 patients who had TBEV RNA in their blood but no central nervous system involvement at the time of evaluation. Median duration of illness was 7 days; 37 (38%) patients were hospitalized. The most fr...

The entrance of wild animals into human settings serves as the access of vector-borne pathogens to susceptible hosts. A red fox (Vulpes vulpes) frequently enters and is quite adapted to living in urban and periurban environments. Due to its living habits, it could be a possible source of tick-borne pathogens, but it could also transfer pathogens th...

In March 2021, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. The phylum was expanded by four families (Aliusviridae, Crepuscuviridae, Myriaviridae, and Natareviridae), three subfamilies (Alpharhabdovirinae, Betarhabdovirinae, a...

We report a case of natural infection with severe acute respiratory syndrome coronavirus 2 transmitted from an owner to a pet ferret in the same household in Slovenia. The ferret had onset of gastroenteritis with severe dehydration. Whole-genome sequencing of the viruses isolated from the owner and ferret revealed a 2-nt difference.

In March 2021, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. The phylum was expanded by four families (Aliusviridae, Crepuscuviridae, Myriaviridae, and Natareviridae), three subfamilies (Alpharhabdovirinae, Betarhabdovirinae, a...

Reports on non-invasive blood sampling are limited, and there are only a few studies on using kissing bugs (Reduviidae) and medicinal leeches (Hirudo medicinalis) for hematology and biochemistry testing in various zoo animal species. The aim of this study was to evaluate the usefulness of non-invasive blood sampling with medicinal leeches for arbov...

We compared the performance of SARS-CoV-2 neutralising antibody testing between 12 European laboratories involved in convalescent plasma trials. Raw titres differed almost 100-fold differences between laboratories when blind-testing 15 plasma samples. Calibration of titres in relation to the reference reagent and standard curve obtained by testing...

Although anti-TBE vaccines are highly effective, vaccine breakthrough (VBT) cases have been reported. With increasing evidence for immune system involvement in TBE pathogenesis, we characterized the immune mediators reflecting innate and adaptive T and B cell responses in neurological and convalescent phase in VBT TBE patients. At the beginning of...

Monitoring infectious diseases is one of the most important pillars of preventative veterinary medicine in zoological collections. The zoo environment offers a great variety of different animal species living in proximity and in contact with small wild animals and vectors (e.g., ticks and mosquitos). In this context, tick-borne encephalitis virus (...

Background Candidatus Neoehrlichia mikurensis (CNM) is an emerging tick-born pathogen and usually causes symptomatic infection only in immunocompromised patients. Apart from one described case found in the literature where cultivation was successful, all cases so far were diagnosed by using broad-range 16S rDNA PCR. Case presentation Our patient p...

Background Multisystem inflammatory syndrome in children (MIS-C) is a rare complication of SARS-CoV-2 infection in the pediatric population, caused by extensive activation of immune system. The understanding of the distorted immune response is still in the early stages. Objectives To analyze comprehensively immune profile in MIS-C patients includi...

Background Multisystem inflammatory syndrome in children (MIS-C) was recognized during the 2020 pandemic of SARS-CoV-2. Because of the relative rarity current knowledge is limited, especially in the European Caucasian population. Objectives To report the epidemiology, clinical and laboratory characteristics of patients with MIS-C in a nationwide c...

Lymphocytic choriomeningitis virus (LCMV) is a neglected human pathogen associated with aseptic meningitis, severe systemic infections in immunocompromised persons, and congenital anomalies. Data on the prevalence of LCMV infections are scarce. We analyzed the seroprevalence of LCMV in continental Croatian regions. A total of 338 serum samples of p...

The biphasic course of tick-borne encephalitis (TBE) is well described, but information on the monophasic course is limited. We assessed and compared the clinical presentation, laboratory findings, and immune responses in 705 adult TBE patients: 283 with monophasic and 422 with biphasic course. Patients with the monophasic course were significantly...

Monitoring infectious diseases is a crucial part of preventive veterinary medicine in zoological collections. This zoo environment contains a great variety of animal species that are in contact with wildlife species as a potential source of infectious diseases. Wild birds may be a source of West Nile virus (WNV) and Usutu (USUV) virus, which are bo...

Objectives Seroprevalence surveys provide crucial information on cumulative SARS-CoV-2 exposure. This Slovenian nationwide population study is the first longitudinal 6-month serosurvey using probability-based sample across all age categories. Methods Each participant supplied two blood samples: 1,316 samples in April 2020 (first round) and 1,211 i...

At the end of 2019, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was discovered in China, causing a new coronavirus disease, termed COVID-19 by the WHO on February 11, 2020. At the time of this paper (January 31, 2021), more than 100 million cases have been recorded, which have claimed over 2 million lives worldwide. The most im...

Background Neutralization tests (NT) are the gold standard for detecting and quantifying anti-SARS-CoV-2 neutralizing antibodies (NAb), but their complexity restricts them to research settings or reference laboratories. Antibodies against S protein receptor binding domain (RBD) have been shown to confer a neutralizing activity against SARS-CoV-2. A...

Francisella tularensis is the etiologic agent of tularemia, a bacterial zoonotic disease. The genome of F. tularensis shows a recent evolutionary change, especially in reservoirs. Variable number of tandem repeats (VNTR) is described as a high-speed molecular clock and can thus be used as a high-resolution typing system. The main objective of our s...

Tick-borne encephalitis (TBE) is associated with a range of disease severity. The reasons for this heterogeneity are not clear. Levels of serum IgG antibodies to TBE virus (TBEV) were determined in 691 adult patients during the meningoencephalitic phase of TBE and correlated with detailed clinical and laboratory parameters during acute illness and...

Orthohantaviruses (family Hantaviridae, order Bunyavirales) can cause two serious syndromes in humans: hemorrhagic fever with renal syndrome (HFRS), associated with the Old World orthohantaviruses, and hantavirus cardiopulmonary syndrome (HCPS), associated with orthohantaviruses in the Americas. In Europe, four different orthohantaviruses (DOBV, PU...

p>In March 2020, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. At the genus rank, 20 new genera were added, two were deleted, one was moved, and three were renamed. At the species rank, 160 species were added, four were deleted...

When a new virus emerges and causes a significant epidemic, the emergency response relies on diagnostics, surveillance, testing, and proposal of treatments if they exist, and also in the longer term, redirection of research efforts toward understanding the newly discovered pathogen. To serve these goals, viral biobanks play a crucial role. The Euro...

[This corrects the article DOI: 10.1371/journal.pntd.0002157.].

Hemorrhagic fever with renal syndrome (HFRS), caused by Dobrava (DOBV) and Puumala (PUUV) orthohantaviruses, is an endemic disease in Slovenia. DOBV is mainly responsible for a more severe disease, whereas PUUV usually causes a milder form. Therefore, the aim of our study was to determine whether any differences in lymphocyte population in patients...

Members of the family Nairoviridae produce enveloped virions with three single-stranded RNA segments comprising 17.1 to 22.8 kb in total. These viruses are maintained in arthropods and transmitted by ticks to mammals or birds. Crimean-Congo hemorrhagic fever virus is tick-borne and is endemic in most of Asia, Africa, Southern and Eastern Europe whe...

West Nile virus (WNV) is a flavivirus transmitted by mosquitoes. Birds are the reservoir for the virus; humans, horses and other mammals are dead-end hosts. Infections caused by WNV in humans can vary from asymptomatic infections to West Nile fever (WNF) or West Nile neuroinvasive disease (WNND). In 1995, a serosurvey was performed in Slovenia on f...

Objectives Accurate population-level assessment of the COVID-19 burden is fundamental for navigating the path forward during the ongoing pandemic, but current knowledge is scant. We conducted the first nationwide population study using a probability-based sample to assess active SARS-CoV-2 infection, combined with a longitudinal follow-up of the en...

Laboratories are currently witnessing extraordinary demand globally for sampling devices, reagents, consumables, and diagnostic instruments needed for timely diagnosis of SARS-CoV-2 infection. To meet diagnostic needs as the pandemic grows, the US Food and Drug Administration (FDA) recently granted several commercial SARS-CoV-2 tests Emergency Use...

We report a case of Babesia crassa-like infection in an asplenic patient in Slovenia in 2014. We diagnosed the infection using microscopy, 18S rRNA sequencing, and serology and monitored parasitemia using digital PCR. With its increasing occurrence, babesiosis should be included in differential diagnoses for immunocompromised patients displaying fe...

We illustrate the potential for specialist laboratory networks to be used as preparedness and response tool through rapid collection and sharing of data. Here, the Emerging Viral Diseases-Expert Laboratory Network (EVD-LabNet) and a laboratory assessment of chikungunya virus (CHIKV) in returning European travellers related to an ongoing outbreak in...

V prispevku prikazujemo primer desetletne deklice z vročino, trombocitopenijo, levkopenijo in patološkimi vrednostmi jetrnih encimov. Povzemamo stopenjsko obrav- navo precej pogostega stanja in glavne diferencialnodia- gnostične možnosti. Pri deklici smo ugotovili šesto otroško bolezen, ki je v njeni starosti neobičajna

We report the case of a ten-year-old girl with a fever, thrombocytopenia, leucocytopenia and pathological liver enzymes. We summarise a stepwise approach to this fairly common condition and the main options for the differential diagnosis. This girl was diagnosed with sixth disease, which is rather unusual for her age

Surveillance of Usutu virus is crucial to prevent future outbreaks both in Europe and in other countries currently naïve to the infection, such as the Americas. This goal remains difficult to achieve, notably because of the lack of large-scale cohort studies and the absence of commercially available diagnostic reagents for USUV. This work started w...

Background Tick-borne encephalitis (TBE) is a potentially severe neurological disease caused by TBE virus (TBEV). In Europe and Asia, TBEV infection has become a growing public health concern and requires fast and specific detection.AimIn this observational study, we evaluated a rapid TBE IgM test, ReaScan TBE, for usage in a clinical laboratory se...

The 2019 11th International Conference on Hantaviruses (ICH 2019) was organized by the International Society for Hantaviruses (ISH), and held on September 1-4, 2019, at the Irish College, in Leuven, Belgium. These ICHs have been held every three years since 1989. ICH 2019 was attended by 158 participants from 33 countries. The current report summar...

Flaviviruses are relevant animal and human pathogens of increasing importance worldwide. The similarities of the initial clinical symptoms and the serological cross-reactivity of viral structural antigens make a laboratory diagnosis of flavivirus infection problematic. The main aim of the present study was the comparative specificity and sensitivit...

In March 2020, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. At the genus rank, 20 new genera were added, two were deleted, one was moved, and three were renamed. At the species rank, 160 species were added, four were deleted,...

Zika virus (ZIKV) infections in humans are considered to be mild or subclinical. However, during the recent epidemics in the Pacific Islands and the Americas, the infection was associated with Quillain-Barré syndrome and congenital infections with fetal brain abnormalities, including microcephaly. Thus, more detailed understanding of ZIKV-host cell...

Information on the association of inflammatory immune responses and disease outcome after tick-borne encephalitis (TBE) is limited. In the present study, we assessed the levels of 24 cytokines/chemokines associated with innate and adaptive immune responses in matched serum and cerebrospinal fluid (CSF) samples of 81 patients at first visit, and in...