This ten-year retrospective study (2012-2021) aimed to investigate the major causes of organ and carcass condemnations identified during post-mortem meat inspection of cattle, sheep, and goats slaughtered at the municipal abattoir of Béjaïa, Algeria, and to estimate the associated economic losses. A total of 140,024 animals were inspected, including 31,723 cattle, 48,700 sheep, and 59,601 goats. Overall, 33,362 organs (24.1%) were condemned, and 399 carcasses (0.3%) were partially or wholly condemned. The highest rate of organ and carcass condemnation was recorded in cattle (32.4%), followed by sheep (24.7%) and goats (19.2%) (P < 0.001). Across all three species, the lungs were the most frequently condemned organs (n = 25,272; 75.7%), followed by the liver (n = 2,899; 8.7%) and heart (n = 2,432; 7.3%) (P < 0.001). In cattle, bovine tuberculosis was the leading cause of organ and carcass condemnation. Liver abscesses represented the main cause of liver condemnation in cattle, sheep, and goats, accounting for 462 of 1,537, 400 of 730, and 389 of 632 condemned livers, respectively. In contrast, pericarditis was the most common cause of heart condemnation in sheep and goats. Over the study period, the estimated direct economic losses attributable to organ and carcass condemnations amounted to USD 518,396.6 in cattle, USD 56,297.5 in sheep, and USD 46,395.8 in goats. These findings highlight the importance of strengthening preventive animal health measures, improving livestock management practices, and reinforcing meat inspection systems to safeguard public health while minimising economic losses across the livestock production chain.
Colibacillosis is a highly prevalent bacterial disease in poultry, resulting in the widespread use of antibiotics for both curative and preventive purposes. Consequently, avian pathogenic Escherichia coli (APEC) continues to act as a reservoir for antibiotic resistance genes, including the mcr-1 gene, which codes for resistance to colistin, a crucial antibiotic in human medicine. The aim of this study was to evaluate the antibiotic resistance pattern of APEC and to investigate the genotyping, phylogrouping, and virulence of mcr-1-positive isolates. A total of 113 APEC were isolated, of which 92% were multidrug resistant (MDR). The mcr-1 gene was detected in 41 isolates originating from turkeys and broilers. Two isolates carried blaTEM, one of which also harboured blaCTX-M encoding beta-lactamases. The Clermont phylogrouping revealed that 76% of the isolates belonged to phylogroup B1. Concerning the detection of the virulence-associated genes, 88% of isolates carried at least 3 genes. The ERIC-PCR classified our isolates into 6 different clusters. Our study highlights the emergence of colistin resistance and MDR, which pose a real threat to poultry production and public health. Control of antibiotic use in the poultry sector is urgent and mandatory.
Bats host a diverse assemblage of ectoparasites that occupy specific anatomical microhabitats, yet the histological effects of these associations remain poorly documented. Here, we report a case of mite infestation of the external ear in the Neotropical bats species Carollia perspicillata and Carollia brevicauda, with a detailed histological characterisation of the auricle and inner ear of C. perspicillata. Bats were captured during biodiversity monitoring programmes in Antioquia, Colombia, and mites were collected and identified morphologically. Histological and histochemical analyses of ear tissues were conducted using haematoxylin and eosin, periodic acid-Schiff, and Masson's trichrome staining. Mites were identified as Spelaeorhynchus praecursor (Spelaeorhynchidae), occurring exclusively on the external ear with infestation frequencies of 6.6% for C. perspicillata and 5.8% for C. brevicauda. Histological examination of the auricle revealed a thin keratinised stratified squamous epithelium, abundant sebaceous glands, well-developed striated skeletal muscle, elastic cartilage, and prominent white adipose tissue at the auricular base. Only minimal focal leukocytic infiltrates were observed, with no evidence of severe pathological alterations associated with mite attachment. The inner ear displayed preserved cochlear architecture, with eosinophilic fibrillar and granular material in the scala vestibuli and scala tympani, interpreted as perilymphatic content or processing artefacts. This study provides baseline histological data on ear tissues in C. perspicillata and documents a localised mite-host association with limited tissue response, contributing to the understanding of bat ectoparasitism and ear morphology in Neotropical chiropterans.
West Nile virus (WNV) is a zoonotic mosquito-borne flavivirus that causes West Nile disease, an emerging and re-emerging infection of major global importance. Horses are an important sentinel species for monitoring WNV circulation. Since viraemia in horses is brief and viral loads in the blood are low, serological assays are the primary tools used to monitor WNV exposure. This study aimed to estimate the seroprevalence of WNV antibodies in horses in Albania. Between 2017 and 2020, 509 serum samples were collected from apparently healthy, unvaccinated horses across different regions of the country. Samples were analysed using two commercial ELISA kits for the detection of total WNV-specific antibodies and WNV-specific IgM. Of the 509 samples tested, 143 (28.1%) were positive for total antibodies, while 12 (2.35%) were IgM-positive, indicating recent infection. As no horse tested positive in both assays, the combined seroprevalence was 30.5% (155/509; 95% CI: 26.6-34.6%), without double counting. A subset of 37 ELISA-positive sera was subsequently tested using the virus neutralisation test (VNT), the gold-standard confirmatory assay for WNV-specific antibodies. The VNT confirmed the presence of WNV-neutralising antibodies in 35/37 (94.6%) samples, with titres ranging from 1:10 to 1:640. These findings indicate widespread WNV circulation in Albania. Compared with previous reports based on samples collected in 2010-2011, seropositivity was higher and evidence of exposure was detected in previously unaffected areas, highlighting the need for continued integrated veterinary and public health surveillance.
Several arthropod vectors, including ticks, sand flies, and mosquitoes, play a prominent role in the introduction and spread of numerous viral diseases. Despite Algeria being at high risk of arbovirus emergence, data on the circulation of arboviruses remain limited, except for some reports on West Nile virus (WNV). Therefore, the aim of this study was to investigate the seroprevalence of antibodies against three arboviruses in several regions of the Algerian Sahara in order to document previous viral exposure. Serum samples collected from dromedaries between May and November 2023 were tested for IgG antibodies against the mosquito-borne viruses Rift Valley fever virus (RVFV) and West Nile virus (WNV), as well as the tick-borne Crimean-Congo haemorrhagic fever virus (CCHFV), using commercial ELISA kits. A total of 224, 79, and 73 serum samples were tested for RVFV, WNV, and CCHFV, respectively. The seroprevalence of IgG antibodies was 2.68% for RVFV, 50.63% for WNV, and 75.34% for CCHFV. Co-seropositivity was most frequently observed for WNV and CCHFV (20.55%, 15/73). Place of residence and sex were significantly associated with CCHFV seropositivity in dromedaries (p < 0.05). Overall, the findings suggest widespread circulation of the studied arboviruses in the eastern Algerian Sahara and indicate the possible presence of these pathogens in camels from previously unexplored regions of the country. The results also highlight the imminent risk facing Algeria, particularly from haemorrhagic viruses, and underscore the importance of strengthening arbovirus surveillance and expanding diagnostic panels to include additional arboviruses.
Highly pathogenic avian influenza A(H5N1) viruses of clade 2.3.4.4b continue to spread globally, causing major outbreaks in wild birds and poultry. In Africa, however, genomic data remain limited, restricting understanding of viral introduction routes and circulation patterns. Here, we report the whole-genome characterisation of an HPAI A(H5N1) virus detected in a common tern (Sterna hirundo) found dead on the Namibian coast during the most recent avian influenza outbreak recorded in the country. Viral RNA was subjected to whole-genome sequencing using the Illumina Viral Surveillance Panel v2 on a NextSeq 1000 platform. Complete or near-complete sequences were obtained for all eight genome segments and deposited in GenBank. Phylogenetic analyses, performed using African clade 2.3.4.4b H5Nx sequences and the closest related sequences identified through database searches, showed that the Namibian virus belonged to clade 2.3.4.4b and clustered within the EA-2024-DI.2 subgenotype. Across all segments, the virus grouped with contemporary European EA-2024-DI.2 viruses circulating during the 2024-2025 epidemic wave, supporting a likely Eurasian origin. For six of the eight segments, it also clustered closely with an EA-2024-DI.2 virus detected in a gull-billed tern in Uganda in December 2024. Molecular analysis identified a polybasic haemagglutinin cleavage site consistent with high pathogenicity and a mutational profile broadly similar to contemporary EA-2024-DI.2 viruses. The HA substitution, associated in previous studies with increased binding to mammalian-type α2-6 receptors, may warrant further investigation. These findings highlight the role of migratory seabirds in H5N1 dissemination and reinforce the need for strengthened genomic surveillance in African wild birds and poultry.
This study examines the seasonal and host sex-age effects on endoparasite infections in a captive population of Barbary sheep (Ammotragus lervia) at the Ben Aknoun zoological park, Algiers, northern Algeria. A total of 440 faecal samples were collected from May 2024 to April 2025 and processed using direct smears and a modified McMaster flotation technique. Parasite prevalence and intensity were analysed using generalised linear mixed models (GLMMs), followed by Tukey-adjusted pairwise comparisons between seasons and host sex-age classes. Microscopic examinations revealed nematodes (strongyles and Strongyloides sp.), cestodes (Moniezia sp. and Taenia sp.), and protozoa (Eimeria spp. and Balantidium sp.). Overall parasite prevalence was high (72.05±2.14%) ranging from 68.75 ±4.38% in summer to 74.07±4.22 % in spring. Strongyles (47.05±2.38%) and Eimeria spp. (46.59±2.38%) were the most prevalent, while Strongyloides sp. showed the lowest prevalence (10.45±1.46%). Overall parasite prevalence did not vary significantly among seasons or sex-age groups (p > 0.05 for all seasonal and sex-age class contrasts), however, Eimeria spp. and Balantidium sp. prevalence showed significant seasonal differences, both peaking in the wet season. Intensity varied significantly between sex-age classes for Moniezia sp. with adult animals having higher mean egg counts than juveniles; and for Balantidium sp. with males having higher mean cyst counts than females and juveniles. Parasitological surveillance especially of vulnerable host classes during periods of risk, anti-parasitic treatments based on confirmed infection cases, and improved enclosure hygiene are needed to preserve animal health and to support conservation efforts for this threatened ungulate species.
Bluetongue (BT) is a vector-borne disease of ruminants caused by bluetongue virus (BTV). After more than a decade without reported cases, BT re-emerged in Serbia in 2025. In August 2025, clinical signs consistent with BT were observed in a sheep flock in western Serbia, including fever, submandibular and head oedema, oral haemorrhages, and cyanosis of the tongue. Real-time RT-PCR targeting segment 10 confirmed BTV infection, and serotyping identified BTV-8. Virus isolation in embryonated chicken eggs yielded multiple BTV-8 isolates, which underwent whole-genome sequencing using Oxford Nanopore and Illumina platforms. Complete or near-complete sequences of all ten genomic segments were obtained. Phylogenetic analysis of segment 2 showed close clustering with recent BTV-8 strains from France, Italy, and Spain (2023-2025), with no evidence of reassortment. The data indicate a likely transboundary introduction of BTV-8 from Western Europe and its rapid spread in Serbia.
Coxiella burnetii, the causative agent of Q fever, is a globally distributed zoonotic pathogen affecting humans, domestic animals, and arthropod vectors. In Algeria, fragmented data suggest widespread circulation, yet no comprehensive quantitative assessment exists. This study aimed to systematically review and meta-analyse the prevalence of C. burnetii in humans, animals, and vectors in Algeria, using a One Health perspective. A systematic search of PubMed, Scopus, Web of Science, and Google Scholar was conducted up to January 2026. Studies reporting serological or molecular detection of C. burnetii in Algeria were included. Random-effects meta-analysis was performed to estimate pooled prevalence, with subgroup analyses by host species, region, and diagnostic method. A total of 35 studies were included, encompassing 8,372 samples and 80 prevalence observations. Pooled prevalence was highest in camels (73.7%; 95% CI: 66.5-79.8%), followed by small ruminants (15.8%; 95% CI: 10.6-22.9%) and cattle (11.8%; 95% CI: 7.2-18.8%). Ticks showed a pooled prevalence of 10.0% (95% CI: 3.2-27.1%), while human infection had a pooled prevalence of 3.7% (95% CI: 0.9-13.9%). The south-eastern region exhibited the highest prevalence, and serological methods generally reported higher rates than molecular methods. High heterogeneity (I² > 75%) was observed across studies. Coxiella burnetii is widely circulating among humans, domestic animals, camels, and ticks in Algeria, with notable variation between hosts and regions. Camels and small ruminants act as major reservoirs, while humans remain at risk, particularly those in close contact with livestock. Integrated One Health surveillance and targeted control strategies are urgently needed to reduce the burden of Q fever.
This study assessed Toxoplasma gondii infection in 92 slaughtered goats from four ecologically distinct regions of Algeria: Laghouat, Medea, Bouira, and Djelfa. Serological analysis was performed using a multispecies indirect ELISA, and histopathological examination targeted heart and diaphragm tissues to detect cysts or suggestive inflammatory lesions. The overall seroprevalence was low (4.3%), with no significant associations with age, sex, or breed. Geographic region significantly influenced seroprevalence: Bouira exhibited the highest rate (18.8%, p < 0.01), while other regions ranged from 0-8.3%. Histopathological analysis revealed a higher prevalence of lesions compatible with T. gondii (10.9%) in both heart and diaphragm. Young goats had higher lesion rates (18.8%) than adults (6.7%), though differences were not statistically significant. Regional differences were pronounced: Bouira showed 37.5% of animals with lesions (p < 0.001), El-Djelfa 16.7% (p < 0.04), while Laghouat remained free of lesions. These findings highlight a geographically clustered distribution of infection. Comparison of ELISA with histopathology indicated high concordance: 4 goats were positive across all methods, while 6 goats were ELISA-negative but tissue-positive, suggesting early, chronic, or low-antibody infections. Overall agreement between ELISA and tissue examination was 93.5%, with a Cohen's kappa of 0.54, indicating moderate to substantial agreement. The study demonstrates that intensive, closed-system goat farming effectively limits exposure to T. gondii, as evidenced by low seroprevalence and limited tissue infection. Importantly, combining serological and histopathological approaches provides a more comprehensive assessment of infection, capturing cases that may be missed by either technique alone. This dual diagnostic strategy enhances epidemiological understanding and improves surveillance, particularly in areas with environmental hotspots like Bouira.
Bluetongue (BT) is a WOAH-notifiable economically important disease of ruminants caused by Bluetongue virus (BTV), transmitted by Culicoides spp. biting midges. Over the past two years, Italy has experienced a marked re-emergence of BT, with thousands of outbreaks reported due to the simultaneous circulation of several BTV strains belonging to serotypes 3, 4, and 8. Moreover, in September 2025, BTV-5 was detected in Sardinia, marking its first occurrence in Europe. Following the first identification by Whole Genome Sequencing, the development of a reliable real-time RT-qPCR-based assay capable of typing the novel BTV-5 ITA 2025 strain was essential, as currently available molecular typing methods targeting BTV segment 2, which encodes the outer capsid protein VP2, are unable to detect this newly emerging strain. Therefore, in this study we developed, optimised, and validated a real-time RT-PCR assay for the detection and typing of BTV-5 ITA 2025 in field samples. The assay is characterised by high sensitivity and specificity, as well as good reproducibility, and can be effectively applied for BTV-5 ITA 2025 diagnosis in the current epidemiological context, supporting surveillance and control strategies.
Bluetongue virus (BTV) and epizootic haemorrhagic disease virus (EHDV) are Culicoides-borne orbiviruses affecting domestic and wild ruminants. Information on their circulation in Namibian wildlife is limited. This study investigated the molecular detection and serotype distribution of BTV and EHDV in wild ruminants from a commercial game farm in the Khomas Region, Namibia, where wildlife and livestock coexist. Between June and September 2019, spleen samples from 62 clinically healthy animals (kudu, oryx, and red hartebeest) were analysed by real-time RT-PCR using pan-BTV and pan-EHDV assays, followed by serotype-specific tests for selected BTV types. Two animals (3.23%) tested positive for EHDV. BTV RNA was detected in 24/62 animals (38.71%), with Ct values ranging from 28.3 to 38.4. BTV-3 and BTV-4 were the most frequently identified serotypes, while one sample was positive for BTV-1; six BTVpositive samples remained untyped. High Ct values and low RNA loads likely limited sequencing success. Although restricted to a single farm and a limited serotype panel, this study provides preliminary molecular evidence of BTV and EHDV circulation in Namibian wild ruminants, highlighting the need for broader epidemiological investigations at the wildlife-livestock interface.
Pathogen-agnostic diagnostics are crucial for the early detection of emerging viruses. Shotgun metagenomic sequencing enables unbiased detection of viral genomes but is frequently constrained by the abundance of host and microbial ribosomal RNA (rRNA), which reduces sensitivity and increases sequencing costs. CRISPR-Cas9-based rRNA depletion has emerged as an alternative to enzymatic methods; however, its performance for the characterization of zoonotic viruses across diverse animal hosts and tissues remains underexplored. We compared CRISPR-Cas9 (Jumpcode CRISPRclean™ Plus) and RNase H-based enzymatic depletion (Ribo-Zero Plus, Illumina) using 12 samples positive for rabies lyssavirus, influenza A virus, West Nile virus or norovirus, from multiple host species and tissues, including both high-quality and degraded RNA. CRISPR-Cas9 efficiently reduced rRNA content (14.5%) but recovered fewer viral reads than Ribo-Zero, which achieved up to 60.7× enrichment. Both methods produced complete viral consensus genomes when RNA quality and viral load were sufficient. However, based on the data generated here, enzymatic depletion currently remains more efficient and cost-effective for viral metagenomics. Further optimization of CRISPR-Cas9 workflows could enhance its utility for viral surveillance and diagnostics.
The "Sentinel Hypothesis" posits that animals often manifest the effects of environmental pollution earlier than humans. This systematic review quantitatively validates this hypothesis within the One Health framework, focusing on three Italian National Interest Sites for Remediation (SINs): Taranto, Campania's "Terra dei Fuochi," and Sardinia. Adhering to PRISMA guidelines, we synthesized data from 76 studies (43 human epidemiological/biomonitoring outcomes, 33 animal sentinel outcomes). In Taranto, excess human cancer incidence (e.g., +40% liver cancer in men) correlates with severe dioxin contamination in the mussel Mytilus galloprovincialis (up to 14.88 pg WHO-TEQ/g). In Campania, polychlorinated biphenyls (PCBs) and dioxins detected in livestock products mirrored contamination found in human breast milk and elevated cancer mortality. In Sardinia, while human cancer epidemiology remains debated, lead accumulation in wild boar (Sus scrofa) liver (mean 6.70 mg/kg) aligns with elevated lead levels in children's hair, highlighting risks from both mining legacies and hunting ammunition. The findings confirm that veterinary surveillance data frequently precede human health alerts, documenting a "systematic delay" in public health response. We recommend integrating veterinary and human surveillance systems to operationalize animal sentinels as early warning tools for environmental health.
Southern Europe, and Italy in particular, has historically been exposed to repeated incursions of orbiviruses, including multiple bluetongue virus (BTV) serotypes and epizootic haemorrhagic disease virus serotype 8. Sardinia, Italy represents a key sentinel location due to its geographic position in the Mediterranean basin. In August 2025, fatal bluetongue cases in sheep were reported in Sardinia during a period of intense BTV circulation in Italy, characterised by widespread outbreaks associated with BTV-3 and BTV-8. These clinical samples tested positive for BTV but could not be serotyped using the available real-time RT-PCR assays. Whole-genome sequencing identified the causative agent as BTV serotype 5 (BTV-5), representing the first detection of this serotype in Europe. The virus was also successfully isolated in cell culture. Segments 2 and 6 showed the highest nucleotide identity with a BTV-5 strain identified in Nigeria in 1982, whereas the rest of the genome seems to be composed by gene segments originating from multiple BTV serotypes circulating in Africa and Europe. At the time of writing, no official reports of BTV-5 circulation were available from Northern Africa; however, during the editorial process, BTV-5 was reported in Tunisia, further supporting the Mediterranean basin as a single interconnected epidemiological ecosystem for orbivirus emergence and spread.
The "One Health" approach is a multi-sectoral and multidisciplinary collaborative strategy, aiming to promote the health of humans, animals and the environment at local, national, regional and global levels. Effective health collaboration across sectors can be achieved through the "One Health" framework by adopting innovative health policies that shift from the concept of current healthcare services for ill people and animals to the prevention of health risks across entire communities: human, animal, plant, and environmental. This requires epidemiological surveillance, the development of risk and threat reporting systems, and the use of both descriptive and analytical epidemiological data to develop and improve overall health outcomes in humans, animals, plants, and the environment. Additionally, economic modelling can help to predict the potential impact of health threats, ensuring that new strategies are both proactive and sustainable, and are linked to health policies implemented from a One Health perspective and based on sound epidemiological studies. This would require securing the required resources, especially the human knowledge and competence necessary to implement these policies effectively. This study reviews the current concept and application of the One Health approach, its integration with the International Health Regulations (IHR) in epidemic and pandemic control, and its strengths and weaknesses. By analysing these factors, we propose a vision for future strategies that effectively incorporate the "One Health" approach into national and international health policies, with the goal of making "One Health" a practical and implementable framework, ensuring the sustainability of global health systems and fostering a healthier world for all.
Varroa destructor is the main parasitic threat to Apis mellifera colonies worldwide and represents a major concern for honey bee health and apicultural sustainability. Oxalic acid (OA) is widely used for the control of varroosis; however, its efficacy is strongly influenced by the presence of capped brood. This pilot field study aimed to evaluate the efficacy and safety of a combined treatment protocol based on Api-Bioxal® administered by trickling and sublimation. The study was carried out in a permanent apiary located in the province of Bergamo (Northern Italy) from October 2024 to February 2025 and involved ten A. mellifera colonies housed in Dadant-Blatt hives. The experimental protocol consisted of one OA trickling treatment followed by two OA sublimations and a control treatment with amitraz. Treatment-induced mite fall was recorded daily for 117 days; brood presence, ambient temperature and pollen influx were monitored throughout the study period, and colony strength was assessed at the beginning and end of the trial using the Liebefeld method. Differences between pre- and post-treatment measurements were analysed using the Wilcoxon signed-rank test. An overall mean of 563.6 Varroa mites per colony was recorded as treatment-induced mite fall. The highest efficacy of OA was observed when treatments were applied in broodless conditions, whereas the presence of capped brood markedly reduced acaricidal efficacy. No abnormal honey bee mortality or adverse effects on colony health were observed. Colony strength increased in 8 out of 10 colonies, with statistically significant differences between pre- and post-treatment assessments (p < 0.012). These results indicate that Varroa destructor populations remain susceptible to oxalic acid when treatments are properly timed in relation to brood presence. A combined protocol of OA trickling and sublimation may enhance varroosis control without negative effects on colony health. Further large-scale studies are required to confirm these preliminary findings and to support evidence-based adjustments to national Varroa control guidelines.
Parasites represent a major constraint in pond-based aquaculture, as their presence can lead to substantial fish mortality and associated economic losses. This study investigated the extent of Argulus infestation in cultured common carp (Cyprinus carpio) reared in a freshwater hatchery in South Sulawesi Province, Indonesia. Two host groups were examined: broodstock (n = 60; 1091.2 ± 58.16 g) and fingerlings (n = 150; 19.6 ± 0.82 g). Identification of Argulus specimens was conducted using morphological examination complemented by molecular analyses. Parasite prevalence and mean intensity were quantified, and Spearman's rank correlation was applied to determine the relationship between fish body weight and infestation severity. Both morphological and molecular evidence confirmed that the Argulus specimens infesting carp in this study were Argulus foliaceus. Fish body weight was significantly correlated with infestation intensity (P < 0.01), with broodstock exhibiting markedly higher prevalence and mean intensity than fingerlings. Preferred attachment sites differed between life stages: the base of the pectoral fins in broodstock and the body surface in fingerlings. These findings indicate that host life stage and body size strongly influence the severity and spatial pattern of A. foliaceus infestations in common carp. The outcomes provide a scientific basis for developing management guidelines to reduce the incidence and spread of Argulus in aquaculture systems.
