Information on the population dynamics of a reservoir species have been increasingly adopted to understand and eventually predict the dispersal patterns of infectious diseases throughout an area. ...Although potentially relevant, to date there are no studies which have investigated the genetic structure of the red fox population in relation to infectious disease dynamics. Therefore, we genetically and spatially characterised the red fox population in the area stretching between the Eastern and Dinaric Alps, which has been affected by both distemper and rabies at different time intervals. Red foxes collected from north-eastern Italy, Austria, Slovenia and Croatia between 2006-2012, were studied using a set of 21 microsatellite markers. We confirmed a weak genetic differentiation within the fox population using Bayesian clustering analyses, and we were able to differentiate the fox population into geographically segregated groups. Our finding might be due to the presence of geographical barriers that have likely influenced the distribution of the fox population, limiting in turn gene flow and spread of infectious diseases. Focusing on the Italian red fox population, we observed interesting variations in the prevalence of both diseases among distinct fox clusters, with the previously identified Italy 1 and Italy 2 rabies as well as distemper viruses preferentially affecting different sub-groups identified in the study. Knowledge of the regional-scale population structure can improve understanding of the epidemiology and spread of diseases. Our study paves the way for an integrated approach for disease control coupling pathogen, host and environmental data to inform targeted control programs in the future.
The objective of this paper is to provide an overview of the current status of rabies in Europe, with special emphasis on Croatia and Southeast and East Europe. Due to the systematic implementation ...of a rabies eradication program by oral vaccination of wild animals, by the end of the 20th century, most West and Central European countries were rabies-free. The EU goal was to eradicate rabies in wildlife and domestic animals by 2020. No matter how achievable the goal seemed to be, the disease is still present in the eastern part of the EU, as was notified in 2020 by two member states—Poland and Romania. Croatia has been rabies-free for the last seven years but given that it borders a non-EU country in which a case of rabies was confirmed in 2020, it will continue to contribute to the maintenance of the rabies-free region. A rabies-free EU can only be achieved by continuous oral vaccination, coordination and a regional approach. The prevention of reintroductions from bordering countries in which rabies has not been eradicated yet, and the support for the eradication efforts made by these countries, are goals still pending.
Despite the implementation of control measures (preventive dog vaccination), rabies has become endemic in Croatia, with red foxes being the main reservoir species. Oral rabies vaccination (ORV) ...campaigns supported by the European Commission have been conducted twice a year since the spring of 2011. The first campaigns were limited to the northern and eastern parts of the country, and from the autumn of 2012, the program was extended to the entire country. The Lysvulpen vaccine containing the SAD Bern strain was used for ORV. Following the vaccination campaigns, the number of rabies cases decreased, and the last positive case was recorded in February 2014. The bait uptake ranged from 24.86% to 84.62% and the immunisation rate from 11.24% to 35.64%.
Vaccination of cattle against lumpy skin disease (LSD) can cause adverse reactions. Here, we report the first complete genome sequence of an LSD virus strain isolated from the skin of a vaccinated ...animal. We confirmed that the sequence of the virus used for vaccination remains stable.
To date, the microbiome, as well as the virome of the Croatian populations of bats, was unknown. Here, we present the results of the first viral metagenomic analysis of guano, feces and saliva (oral ...swabs) of seven bat species (
,
,
,
,
,
and
) conducted in Mediterranean and continental Croatia. Viral nucleic acids were extracted from sample pools, and analyzed using Illumina sequencing. The presence of 63 different viral families representing all seven Baltimore groups were confirmed, most commonly insect viruses likely reflecting the diet of insectivorous bats. Virome compositions of our samples were largely impacted by the sample type: invertebrate-infecting viruses were most frequently found in feces, bacterial viruses in guano, whereas vertebrate-infecting viruses were most common in swabs. Most vertebrate-infecting virus sequences were assigned to retroviruses, parvoviruses, iridoviruses, and poxviruses. We further report the complete genome sequence of a novel adeno-associated virus, densovirus and a near complete length genome sequence of a novel iflavirus. Additionally, one of the most interesting findings in this study was the difference in viromes between two contrasting habitats, the continental and Mediterranean Croatia.
Lumpy skin disease (LSD) is an emerging, transboundary viral pox disease affecting cattle of all ages and breeds. The serological assay for monitoring immunity following vaccination is a virus ...neutralization test (VNT/OIE) that determines the neutralization index (NI). The first validated enzyme-linked immunosorbent assay (ELISA; IDVet) has become commercially available, facilitating large-scale serosurveillance for LSD. Although the VNT is labor intensive and time consuming, it is still the recommended test by the OIE. Thus, in this study, we modified the virus neutralization test by employing Madin-Darby bovine kidney (MDBK) cells. The qualitative results obtained with the modified method were compared to the qualitative results obtained by VNT/OIE and ELISA. We used blood sera received within a surveillance program for LSD in 2018. In total, 291 serum samples were tested using VNT/MDBK and ELISA. Of 291 samples, 80 samples were tested by VNT/OIE and used for comparison of the performances between VNT/MDBK and VNT/OIE. The compatibility of results obtained by VNT/MDBK and VNT/OIE resulted in a kappa index of 0.9 with overall proportion agreement of 0.96. Agreement between VNT/MDBK and VNT/OIE was achieved in 56 positive and 21 negative samples. The compatibility of results obtained by ELISA and VNT/MDBK were compared on 291 samples in total and resulted in a kappa index 0.834 with overall proportion agreement of 0.955. Agreement between ELISA and VNT/MDBK was achieved in 238 positive and 40 negative samples. The results obtained demonstrated a strong correlation between VNT/MDBK and the other two methods, indicating the suitability of VNT/MDBK for the detection of the LSD virus-specific neutralizing antibodies.
Although canine adipose derived stem cells (cASCs) morphology characteristics and differentiation ability are well documented, transcriptome alterations of undifferentiated cASCs during ex vivo ...cultivation remain unknown. Here we demonstrate, for the first time, the transcriptome composition of isolated cASCs in undifferentiated state originating from six donors. Transcriptome changes were monitored during ex vivo cultivation between passage 3 (P3) and P5, which are mostly used in therapy. Influence of donors’ age in given passage number on transcriptome composition was also investigated. Cultivation from P3 to P5 resulted in 16 differentially expressed genes with cooverexpression of pluripotency and self-renewal transcription factors genes SOX2 and POU5F1 dominant in old donors’ cells. Furthermore, cASCs demonstrated upregulation of IL-6 in young and old donors’ cells. In addition, ex vivo cultivation of cASCs revealed well-known morphological alterations accompanied with decrease in expression of CD90 and CD44 markers in P4 and higher monitored by flow cytometry and successful osteo- and chondrodifferentiation but inefficient adipodifferentiation in P3. Our results revealed the impact of ex vivo cultivation on nature of cells. Correlation of transcriptome changes with secretome composition is needed and its further impact on therapeutic potential of cASCs remains to be evaluated in clinical trials.
•Two new subgroups of bovine respiratory syncytial virus were observed in Croatia.•New subgroup VIII strains dominated in 2014–2016, replacing subgroup VII strains.•Subgroup II and new subgroup VIII ...strains co-circulated in Croatia.•Subgroups II and VII harbour unique mutations in G gene, allowing immune escape.•Intensive bovine vaccination resulted in emergence of new virus variants.
Bovine respiratory syncytial virus (BRSV) represents an important causative agent of respiratory tract disease in cattle. This study describes the genetic diversity of BRSV strains detected in beef cattle herds in Croatia during four consecutive years, from the end of 2011 to April 2016. Genetic diversity of circulating Croatian strains is reflected in their clustering within three different genetic subgroups. Analysis of representative BRSV G gene sequences revealed that infections in Croatia were caused by BRSV strains belonging to two new subgroups (VII and VIII identified herein for the first time). In 2014–2016, the subgroup VII strains were replaced with BRSV strains clustered in the previously unidentified subgroup VIII. Furthermore, co-circulation of subgroup II and new subgroup VIII strains in Croatia was recorded in the same time period. Sequences of Croatian BRSV strains within subgroups II and VII revealed unique mutations within an essential immunodominant region, demonstrating continuous evolution of viral mechanisms for immune escape.
Background Bovine viral diarrhea is a contagious disease of domestic and wild ruminants and one of the most economically important diseases in cattle. Bovine viral diarrhea virus belongs to the genus ...Pestivirus, within the family Flaviviridae. The identification and elimination of the persistently infected animals from herds is the initial step in the control and eradication programs. It is therefore necessary to have reliable methods for diagnosis of bovine viral diarrhea virus. One of those methods is immunohistochemistry. Immunohistochemistry on formalin fixed, paraffin embedded tissue is a routine technique in diagnosis of persistently infected cattle from ear notch tissue samples. However, such technique is inappropriate due to complicated tissue fixation process and it requires more days for preparation. On the contrary, immunohistochemistry on frozen tissue was usually applied on organs from dead animals. In this paper, for the first time, the imunohistochemistry on frozen ear notch tissue samples was described. Findings Seventeen ear notch tissue samples were obtained during the period 2008-2009 from persistently infected cattle. Samples were fixed in liquid nitrogen and stored on -20°C until testing. Ear notch tissue samples from all persistently infected cattle showed positive results with good section quality and possibility to determinate type of infected cells. Conclusions Although the number of samples was limited, this study indicated that immunohistochemistry on formalin fixed paraffin embedded tissue can be successfully replaced with immunohistochemistry on frozen ear notch tissue samples in diagnosis of persistently infected cattle.
Rabies is the only known zoonotic disease of bat origin in Europe. The disease is caused by species belonging to the genus Lyssavirus. Five Lyssavirus species, i.e., European bat lyssavirus (EBLV)-1, ...EBLV-2, Bokeloh bat lyssavirus, Lleida bat lyssavirus, and West Caucasian bat virus, have been identified in European bats. More recently, a proposed sixth species, Kotalahti bat lyssavirus, was detected. Thus, in this study, active surveillance was initiated in order to obtain insights into the prevalence of lyssaviruses in Croatian bat populations and to improve our understanding of the public health threat of infected bats.
In total, 455 bats were caught throughout Continental and Mediterranean Croatia. Antibodies were found in 20 of 350 bats (5.71%, 95% confidence interval 3.73-8.66). The majority of seropositive bats were found in Trbušnjak cave (Continental Croatia, Eastern part), and most seropositive bats belonged to Myotis myotis (13/20). All oropharyngeal swabs were negative for the presence of Lyssavirus.
The presence of lyssaviruses in bat populations was confirmed for the first time in Croatia and Southeastern Europe. The results of this study suggest the need for further comprehensive analyses of lyssaviruses in bats in this part of Europe.