Diversity of Trichinella species in carnivores from Bosnia and Herzegovina.

BACKGROUND: In Bosnia and Herzegovina, domestic and wild carnivores represent a significant driver for the transmission and ecology of zoonotic pathogens, especially those of parasitic aetiology. Nevertheless, there is no systematic research of Trichinella species in animals that have been conducted in Bosnia and Herzegovina, even though trichinellosis is considered the most important parasitic zoonosis. The available results of the few studies carried out in Bosnia and Herzegovina are mainly related to the confirmation of parasitic larvae in the musculature of domestic pigs and wild boars or data related to trichinellosis in humans. The objective of our study was to present the findings of a comprehensive investigation into the species composition of Trichinella among 11 carnivorous species within the territory of Bosnia and Herzegovina, as follows: red fox (Vulpes vulpes), grey wolf (Canis lupus), brown bear (Ursus arctos), wildcat (Felis silvestris), pine marten (Martes martes), European badger (Meles meles), weasel (Mustela nivalis), European polecat (Mustela putorius), Eurasian lynx (Lynx lynx), but also dog (Canis lupus familiaris) and cat (Felis catus). RESULTS: In the period 2013-2023, carnivore musculature samples (n = 629), each consisting of 10 g of muscle tissue, were taken post-mortem and individually examined using the artificial digestion method. In the positive samples (n = 128), molecular genotyping and identification of parasitic larvae of Trichinella spp. were performed using a PCR-based technique up to the species/genotype level. Positive samples were used for basic PCR detection of the genus Trichinella (rrnS rt-PCR technique) and genotyping (rrnl-EVS rt-PCR technique). The Trichinella infection was documented for the first time in Bosnia and Herzegovina among red foxes, grey wolves, brown bears, dogs, badgers and Eurasian lynx, with a frequency rate of 20.3%. Additionally, the presence of T. britovi infection was newly confirmed in Bosnia and Herzegovina, marking the initial documented cases. Furthermore, both T. britovi and T. pseudospiralis infections were observed in the wildcat population, whereas T. britovi and T. spiralis infections were detected in pine martens. Consistent with previous research, our findings align particularly regarding carnivores, with data from other countries such as Germany, Finland, Romania, Poland and Spain, where T. britovi exhibits a wider distribution (62.5-100%) compared to T. spiralis (0.0-37.5%). T. britovi is more common among sylvatic carnivores (89.0%), while T. spiralis prevails in wild boars (62.0%), domestic swine (82.0%) and rodents (75.0%). CONCLUSION: The results of our study represent the first molecular identification of species of the genus Trichinella in Bosnia and Herzegovina. Additionally, our findings underscore the necessity for targeted epidemiological studies to thoroughly assess trichinellosis prevalence across diverse animal populations. Considering the relatively high frequency of trichinellosis infection in investigated animal species and its public health implications, there is an evident need for establishing an effective trichinellosis surveillance system in Bosnia and Herzegovina.

First Report of Benzimidazole Resistance in Field Population of Haemonchus contortus from Sheep, Goats and Cattle in Bosnia and Herzegovina.

Haemonchus contortus is a globally significant parasitic nematode in ruminants, with widespread resistance to benzimidazole due to its excessive and prolonged use. Given the extensive use of benzimidazole anthelmintics in Bosnia and Herzegovina, we hypothesized that resistance is prevalent. The aim of this study was to identify the presence of anthelmintic resistance to benzimidazole in H. contortus from naturally infected sheep, goats and cattle in Bosnia and Herzegovina through the detection of the Phe/Tyr polymorphism in the amino acid at position 200 of the ß-tubulin protein. From 19 locations in Bosnia and Herzegovina, a total of 83 adult H. contortus were collected from the abomasum of ruminants. Among these, 45 H. contortus specimens were isolated from sheep, 19 from goats and 19 from cattle. Results showed that 77.8% of H. contortus in sheep exhibited homozygous resistant genotypes at position 200 of the ß-tubulin gene, with 15.5% being heterozygous. In goats, all tested H. contortus (100%) were homozygous resistant, and no heterozygous resistant or homozygous sensitive genotypes were found. Cattle had 94.7% homozygous resistant H. contortus, with no heterozygous resistant genotypes detected. In H. contortus from sheep and cattle, 6.7% and 5.3%, respectively, displayed homozygous sensitive genotypes. This study, for the first time, highlights the presence of a resistant population of H. contortus in sheep, goats and cattle in Bosnia and Herzegovina, using the rt-qPCR method. The resistance likely spread from sheep or goats to cattle, facilitated by shared pastures and the practice of transhumance, indicating a widespread and growing issue of anthelmintic resistance.

Metagenomic Sequencing of Lloviu Virus from Dead Schreiber's Bats in Bosnia and Herzegovina.

Bats are a natural host for a number of viruses, many of which are zoonotic and thus present a threat to human health. RNA viruses of the family Filoviridae, many of which cause disease in humans, have been associated with specific bat hosts. Lloviu virus is a Filovirus which has been connected to mass mortality events in Miniopterus schreibersii colonies in Spain and Hungary, and some studies have indicated its immense zoonotic potential. A die-off has been recorded among Miniopterus schreibersii in eastern Bosnia and Herzegovina for the first time, prompting the investigation to determine the causative agent. Bat carcasses were collected and subjected to pathological examination, after which the lung samples with notable histopathological changes, lung samples with no changes and guano were analyzed using metagenomic sequencing and RT-PCR. A partial Lloviu virus genome was sequenced from lung samples with histopathological changes and found to be closely related to Hungarian and Italian virus sequences. Further accumulation of mutations on the GP gene, coding the glycoprotein responsible for cell tropism and host preference, enhances the need for further characterization and monitoring of this virus to prevent spillover events and protect human health.

Molecular characterization and phylogenetic analysis of highly pathogenic H5N1 clade 2.3.4.4b virus in Bosnia and Herzegovina.

Influenza A virus continues to represent a growing problem affecting mainly birds but with an increasing number of mammal transmission events reported each year. Nevertheless, molecular characterization and phylogenetic analysis of influenza A viruses originating from all confirmed cases have not been systematically performed in all parts of the world. In this study, we investigated a sample originating from a mute swan that died in November 2021 in the northern part of Bosnia and Herzegovina with RT-qPCR and whole genome sequencing using ONT MinION. It was diagnosed as a highly pathogenic Influenza A virus, subtype H5N1 of 2.3.4.4b clade, and phylogenetic analysis revealed high sequence homology with other European HPAI H5N1 sequences at the time. The notable detected mutations in HA (N110S and T139P) and NA genes (H155Y), that facilitate the host specificity shift and enable the resistance to some antiviral drugs respectively, underscore the necessity of virus evolution surveillance. Therefore, the rapid dissemination of information, including virological and molecular data, is essential for the introduction of tailored prevention measures for infected animals, providing clearer insight and better awareness of a potential public health threat.

First detection of Echinococcus multilocularis in Bosnia and Herzegovina.

Echinococcus multilocularis has been spreading through Central Eastern Europe but has not yet been reported in Bosnia and Herzegovina (B&H). Recently, this parasite is confirmed in Croatia suggesting the movement of the parasite's distribution limit further south. Given that there is no surveillance or monitoring system for echinococcosis in B&H, our study was designed as a pilot study of E. multilocularis. A total of 57 red foxes originating from 24 localities all over the country were collected during the routine rabies monitoring, autopsied and examined for the presence of echinococcosis. Based on intestinal scraping technique and microscopy, E. multilocularis adult worms have been detected in one (1/57, 1.75%) red fox. To verify this finding and to differentiate Echinococcus spp., DNA extracted from adult worms was subjected to species-specific PCR targeting part of the mitochondrial 12S ribosomal RNA gene. E. multilocularis PCR-positive samples were further confirmed by NGS sequencing of a 203 bp amplified fragment of 12S rRNA, which has been deposited in GenBank (Accession no.: OP047920). This finding represents the first detection of E. multilocularis in B&H, strongly suggesting its presence in the country. The confirmation of the parasite in the same locality where migrants/refugees temporarily stay on their route to Western Europe highlights the need for a One Health approach in addressing all future questions. Moreover, the first detection of E. multilocularis in B&H warrants the need for the implementation of an appropriate state surveillance program.

Serologic and molecular evidence for circulation of Crimean-Congo hemorrhagic fever virus in ticks and cattle in Bosnia and Herzegovina.

Crimean-Congo haemorrhagic fever virus is a tick-borne zoonotic agent of the genus Orthonairovirus, and the causal agent of Crimean-Congo haemorrhagic fever in humans. The study is aimed at investigating the presence of CCHFV RNA in ticks and cattle in Bosnia and Herzegovina (B&H), as well as the exposure of cattle to CCHFV in this country. Only one pool of three male Hyalomma marginatum ticks tested positive for viral RNA (3/760, 0.39%). No viral RNA was detected in 206 bovine blood samples using real-time reverse-transcriptase PCR (RT-qPCR). The overall seroprevalence of CCHFV in the cattle population was estimated as 14.97% (72/481). The results indicate the presence and the established circulation of CCHFV in B&H. Considering the endemic character of CCHFV in the Balkans as well as our results, the possibility that CCHFV is endemic in the territory of Bosnia and Herzegovina is considered to be very high.

The Evidence of SARS-CoV-2 Human-to-Pets Transmission in Household Settings in Bosnia and Herzegovina.

The infection with SARS-CoV-2 virus in cats and dogs raised issue of human-to-animal transmission of SARS-CoV-2 in domestic pets in close contacts with their owners. Our study was designed to research this in the framework of Bosnia and Herzegovina. Using ELISA, AFIAS fluorescent immunoassay, RT-qPCR and WGS on Nanopore MinION platform with ARTIC Network Amplicon sequencing protocol for SARS-CoV-2, we showed that three out of thirteen dogs and one out of five cats from the households with confirmed human cases of COVID-19 in Bosnia-Herzegovina were infected with SARS-CoV-2. The high viral RNA load was detected in samples collected from a 4-year-old male Havanese (Ct = 12.52), a 6-year-old German Shepherd (Ct = 21.36) and a 9-year-old female American Staffordshire terrier (Ct = 25.74). The antibody response in dogs and one cat was observed. The viral genetic sequences from dogs were identical to the sequences detected in the owners suggesting the human-to-animal transmission of the virus. These findings, especially the low initial Ct values detected, from the public health perspective additionally stress the need for precautionary measures to protect both humans and animals.

First evidence of Crimean-Congo haemorrhagic fever virus circulation in Bosnia and Herzegovina.

BACKGROUND: Crimean-Congo haemorrhagic fever (CCHF) is a widespread tick-borne zoonosis with reported detection of virus and/or virus-specific antibodies from over 57 countries across Africa, Asia, Europe and the Middle East and is endemic in the Balkans. Detection of Crimean-Congo Haemorrhagic Fever Virus (CCHFV) antibodies in domestic ruminants has been important in providing initial evidence of virus circulation and in localising CCHFV high-risk spots for human infection. OBJECTIVES: The present study investigated the possible exposure of sheep to CCHFV in Bosnia and Herzegovina (B&H). METHODS: To investigate the presence of anti-CCHFV antibodies in sheep, all sera (n = 176) were tested using multi-species double antigen enzyme-linked immunosorbent assay (ELISA). Reactive sera were further complementary tested by adapted commercial indirect immunofluorescence assay (IFA) using FITC-conjugated protein G instead of anti-human immunoglobulins. RESULTS: CCHFV specific antibodies were detected in 17 (9.66%) animals using ELISA test. All negative sera were determined as negative by both tests, while 13 out of 17 ELISA-positive reactors were also determined as unambiguously positive by IFA test. The age group with the highest proportion of seropositive rectors were the oldest animals. CONCLUSIONS: This is the first report of anti-CCHFV antibodies in sheep from B&H providing the evidence of CCHFV circulation in the country's sheep population. So far, these findings indicate the circulation of the virus in the westernmost region of the Balkans and point to the potential CCHFV spread further out of this endemic area.

Contamination of Soil and Vegetation with Developmental Forms of Parasites in the Area of the Federation of Bosnia and Herzegovina.

BACKGROUND: According to the WHO (2019), more than 1.5 billion people worldwide are infected with soil-transmitted parasites. Previous research in the Federation of Bosnia and Herzegovina (FB&H) was mainly conducted in the area of the Sarajevo Canton. Therefore, the aim of the research was to explore contamination of soil and vegetation with developmental forms of parasites in the other cantons of FB&H. METHODS: Between Apr and Oct 2018, a total of 1,618 soil and vegetation samples were taken from 386 different locations in the 9 cantons of the FB&H. RESULTS: Positive samples were observed, 65/66 (98.48%) municipalities/cities and on 239/386 (61.92%) locations. Out of 1,618 samples taken in total (1,263 soil samples and 355 vegetation samples), 357 (22.06%) were positive, out of which 337 (26.68%) and 20 (5.63%) were soil and plant samples, respectively. In total, the following adult and developmental forms were identified: Taeniidae eggs (7.30%), Toxocara spp. eggs (62.08%), Ancylostomatidae eggs (25.00%), Trichuris spp. eggs (9.55%), Capillaria spp. eggs (3.37%), Toxascaris leonina eggs (1.40%), Nematodes larvae (19.38%), Giardia duodenalis cysts (5.06%), Cryptosporidium spp. oocysts (1.4%), oocysts and cysts of different species of Protozoa (3.93%). CONCLUSION: The identified developmental forms of parasites pose a permanent threat to human health. It is necessary to carry out measures to reduce the contamination of soil and vegetation in coordination with systematic solutions (legislation), paralelly with contribution of animal owners, veterinarians, physicians, ecologists, parents and all the others involved in this issue.

Phylogenetic pattern of SARS-CoV-2 from COVID-19 patients from Bosnia and Herzegovina: lessons learned to optimize future molecular and epidemiological approaches.

This is the first report of molecular and epidemiology findings from Bosnia and Herzegovina related to ongoing severe acute respiratory syndrome coronavirus 2 epidemic. Whole genome sequence of four samples from coronavirus disease 2019 (COVID-19) outbreaks was done in two laboratories in Bosnia and Herzegovina (Veterinary Faculty Sarajevo and Alea Genetic Center). All four BiH sequences cluster mainly with European ones (Italy, Austria, France, Sweden, Cyprus, and England). The constructed phylogenetic tree indicates possible multiple independent introduction events. The data presented contribute to a better understanding of COVID-19 in the current reemergence of the disease.

A Unique Case of Fatal Coinfection Caused by Leptospira spp. and Hepatozoon canis in a Red Fox Cub (Vulpes vulpes).

Red foxes are the most abundant wild carnivore species in Europe commonly exposed to pathogenic Leptospira and Hepatozoon canis. Despite high seroprevalence, the clinical disease caused by these pathogens in red foxes has never been reported. Herein, we report the first-ever case of a fatal Leptospira spp. and H. canis coinfection in a two-month-old red fox cub with acute haemolytic anaemia, mild bronchopneumonia, intraalveolar haemorrhage, and tubulonephrosis. The presence of pathogenic Leptospira spp. DNA was detected in the kidney and lung tissues of the infected animal. In contrast to our previous knowledge, we believe that such fatal cases due to concomitant infection by Leptospira spp. and H. canis, especially in young animals, may commonly occur in nature. However, further studies are required to identify other factors that possibly contribute to the severity and the pathogenic effect of Leptospira spp. and H. canis infections in red foxes.

External quality assessment of Rift Valley fever diagnosis in 17 veterinary laboratories of the Mediterranean and Black Sea regions.

Rift Valley fever (RVF) is an arboviral zoonosis that primarily affects ruminants but can also cause illness in humans. The increasing impact of RVF in Africa and Middle East and the risk of expansion to other areas such as Europe, where competent mosquitos are already established, require the implementation of efficient surveillance programs in animal populations. For that, it is pivotal to regularly assess the performance of existing diagnostic tests and to evaluate the capacity of veterinary labs of endemic and non-endemic countries to detect the infection in an accurate and timely manner. In this context, the animal virology network of the MediLabSecure project organized between October 2016 and March 2017 an external quality assessment (EQA) to evaluate the RVF diagnostic capacities of beneficiary veterinary labs. This EQA was conceived as the last step of a training curriculum that included 2 diagnostic workshops that were organized by INIA-CISA (Spain) in 2015 and 2016. Seventeen veterinary diagnostic labs from 17 countries in the Mediterranean and Black Sea regions participated in this EQA. The exercise consisted of two panels of samples for molecular and serological detection of the virus. The laboratories were also provided with positive controls and all the kits and reagents necessary to perform the recommended diagnostic techniques. All the labs were able to apply the different protocols and to provide the results on time. The performance was good in the molecular panel with 70.6% of participants reporting 100% correct results, and excellent in the serological panel with 100% correct results reported by 94.1% of the labs. This EQA provided a good overview of the RVFV diagnostic capacities of the involved labs and demonstrated that most of them were able to correctly identify the virus genome and antibodies in different animal samples.

Reproductive Performance in a Selected Sample of Dairy Farms in Una-Sana Canton, Bosnia and Herzegovina.

BACKGROUND: The production of milk and dairy products and their placement on the market represent a constant profit for the farmers/producers in Bosnia and Herzegovina (BH). The profitable operation of the dairy farms is influenced by the reproductive performance of the lactating animals. This study assessed individual animal reproductive characteristics in selected dairy farms and described their reproductive performance indicators. RESULTS: The median age at first insemination was 493 days (5th-95th percentile range 429-840), while the age at first calving was 802 days (5th-95th percentile range 708-1168). The median pregnancy proportion at first insemination was 40% (5th-95th percentile range 17-62), while the cumulative pregnancy rate calculated at day-60, day-80, day-100, and day-120 showed that approximately 64% of all pregnancies happened before day-120. The calculated interservice intervals showed that approximately 69% of the repeat breeding animals came back to the oestrus in the period of 18 to 24 days. This is an indication of very good oestrus detection in selected dairy farms. The mean number of services per pregnancy was 2.61 (range 1-12). The median calving-to-first-insemination interval was 62.5 days (5th-95th percentile range 16-408). The calving-to-conception interval was 101 day (5th-95th percentile range 36-506). Finally, the calving interval was 385 days (5th-95th percentile range 329-773). CONCLUSIONS: There is a need for an organised, regular, and more comprehensive recording system for the reproduction of dairy cattle among dairy farms in Una-Sana Canton. The calculated reproductive measures indicated an undulant trend in reproductive performance among selected dairy farms in Una-Sana Canton. Knowing the apparent reproductive indicators described in this study, the farmers and veterinary authorities may identify and correct areas in their management that contribute to the reproductive underperformance.

An update of the Culicoides (Diptera: Ceratopogonidae) checklist for the Balkans.

BACKGROUND: The prime significance of species belonging to the genus Culicoides Latreille, 1809 (Diptera: Ceratopogonidae) is their ability to transmit viruses such as bluetongue virus (BTV) to wild and domestic ruminants. Prior to 1998, BTV was considered exotic in Europe, but according to recent history of its outbreaks, it has become endemic in southern and eastern European countries circulating beyond its expected historical limits, into the Balkan region. The wind-borne long-distance dispersal of Culicoides spp. over water bodies and local spreading between farms emphasize the necessity of filling in the information gaps regarding vector species distribution. In most Balkan countries, data on Culicoides fauna and species distribution are lacking, or information is old and scarce. RESULTS: During this study, 8586 specimens belonging to 41 species were collected. We present the first faunistic data on Culicoides species in the former Yugoslav Republic of Macedonia (FYROM), Kosovo, Montenegro and Serbia. For other countries (Bosnia and Herzegovina, Bulgaria and Croatia), all historical records were compiled for the first time and then expanded with our findings to various extents. In all countries, confirmed or suspected BTV vector species belonging to the subgenera Avaritia and Culicoides were collected. The total number of species sampled during our field collections was 20 in Bosnia and Herzegovina (15 new records), 10 in Bulgaria (2 new records), 10 in Croatia (5 new records), 13 in FYROM, 9 in Kosovo, 15 in Montenegro, and 28 in Serbia. Of these, 14 species were registered for the first time in this part of the Balkans. CONCLUSIONS: This paper provides the first data about Culicoides fauna in FYROM, Kosovo, Montenegro and Serbia, as well as new records and an update on the checklists for Bosnia and Herzegovina, Bulgaria and Croatia. These findings provide preliminary insights into the routes of BTV introduction and spreading within the Balkans, and present a valuable contribution to further research related to Culicoides-borne diseases in Europe.

Possible sources and spreading routes of highly pathogenic avian influenza virus subtype H5N1 infections in poultry and wild birds in Central Europe in 2007 inferred through likelihood analyses.

Recurrent outbreaks of H5N1 HPAIV occurred in several Central European countries in 2007. In-depth phylogenetic analyses which included full-length genomic sequences of the viruses involved were performed to elucidate possible origins of incursions and transmission pathways. Tree reconstructions as well as host-shift and ancestral area inferences were conducted in a maximum likelihood framework. All viruses belonged to a separate subgroup (termed "EMA-3") within clade 2.2, and, thus, were distinct from two lineages of HPAIV H5N1 viruses (termed "EMA-1" and "EMA-2") present in the same geographic area in 2006. Analysis of concatenated coding regions of all eight genome segments significantly improved resolution and robustness of the reconstructed phylogenies as compared to single gene analyses. At the same time, the methodological limits to establish retrospectively transmission networks in a comparatively small geographic region and spanning a short period of time became evident when only few corroborating field-epidemiological data are available. Ambiguities remained concerning the origin of the EMA-3 viruses from a region covering Southeast Germany and the Czech Republic as well as routes of spread to other European countries. AIV monitoring programmes in place for wild birds and poultry in these countries did not reveal presence of these viruses in either population. Host switches between domestic poultry and wild bird populations occurred several times. Analysis of outbreaks in Northeast Germany and nearby Northern Poland in December 2007 demonstrated that geographic and even temporal vicinity of outbreaks does not necessarily indicate a common source of incursion.

Highly pathogenic avian influenza virus subtype H5N1 in mute swans (Cygnus olor) in Central Bosnia.

In order to determine the actual prevalence of avian influenza viruses (AIVs) in wild birds in Bosnia and Herzegovina, extensive surveillance was carried out between October 2005 and April 2006. A total of 394 samples representing 41 bird species were examined for the presence of influenza A virus using virus isolation in embryonated chicken eggs, PCR, and nucleotide sequencing. AIV subtype H5N1 was detected in two mute swans (Cygnus olor). The isolates were determined to be highly pathogenic avian influenza (HPAI) virus and the hemagglutinin sequence was closely similar to A/Cygnus olor/Astrakhan/ Ast05-2-10/2005 (H5N1). This is the first report of HPAI subtype H5N1 in Bosnia and Herzegovina.