Zoonoses and Public Health最新文献

Background: West Nile virus (WNV) is the most widely distributed mosquito-borne flavivirus. Over the past decade, its spread across Europe has raised significant concerns for both public and animal health. Although WNV exposure has been evidenced in various wild mammal species in Spain, no seroepidemiological studies have been conducted on this flavivirus in wild lagomorphs so far.

Aim: This study aimed to assess WNV exposure in European wild rabbit (Oryctolagus cuniculus) and Iberian hare (Lepus granatensis) populations inhabiting Spanish Mediterranean ecosystems.

Methods: Sera from 540 wild lagomorphs (399 European wild rabbit and 141 Iberian hares), from 106 hunting grounds distributed throughout Andalusia (southern Spain), were collected between the 2018/2019 and 2022/2023 hunting seasons.

Results: Antibodies against flavivirus were detected by blocking enzyme-linked immunosorbent assay (bELISA) in 5.0% (27/540; 95% CI: 3.2-6.8) of the wild lagomorphs. Exposure to WNV was confirmed in 4.8% (19/394; 95% CI: 2.7-6.9) of wild rabbits and 0.7% (1/141; 95% CI: 0.0-2.1) of Iberian hares by virus microneutralisation test. Anti-WNV antibodies were found in wild lagomorphs sampled from three (2.8%) hunting grounds located in western Andalusia during the seasons 2020-2021 and 2021-2022. Remarkably, this spatiotemporal distribution overlaps with the largest outbreak of WNV in Spain. Antibodies against Usutu virus and Bagaza virus were not detected in the wild lagomorph populations analysed.

Conclusions: This study constitutes the first report of WNV exposure in wild rabbit in Spain and in Iberian hare worldwide. While these species seem not play a primary role in the epidemiology of the virus, they could serve as sentinel for monitoring WNV in Iberian Mediterranean ecosystems.

Introduction: Toxoplasma gondii is a parasitic protozoan capable of infecting warm-blooded animals, including humans, and is the causative agent of toxoplasmosis. Wild boars (Sus scrofa) serve as reservoirs for zoonotic pathogens like T. gondii, which can cause disease in humans if transmitted. This study aimed to assess the seroprevalence and molecular prevalence of T. gondii in wild boars in Khuzestan Province, Iran.

Methods: Seroprevalence of T. gondii antibodies was assessed using enzyme-linked immunosorbent assay (ELISA), employing a commercial kit (Calbiotech), whereas molecular detection was carried out through polymerase chain reaction (PCR) targeting the B1 gene of T. gondii on tissue samples (tongue, muscle, diaphragm and heart). Thirty wild boars were sampled from the regions of Shush, Shushtar, Dezful and Abadan, and both blood and tissue samples were analysed.

Results: In this study, the seroprevalence of T. gondii antibodies was found to be 83.3% (25/30) among wild boar serum samples using ELISA. Molecular detection through PCR identified T. gondii DNA in 46.7% (14/30) of tissue samples, with the highest detection rates in tongue tissues (64%), followed by muscle (21%) and diaphragm (14%). No positive results were found in heart samples, and no animal had multiple tissues testing positive. All PCR-positive cases corresponded with positive ELISA results, and a statistically significant difference was observed in parasite prevalence across different tissues (p = 0.002).

Conclusion: Although consumption of wild boar meat is banned in Iran, illegal hunting and consumption remain a concern. The high prevalence of T. gondii in wild boars poses a potential risk for transmission through the illegal consumption of undercooked or raw meat. This study highlights the need for public health interventions to control the illegal trade of wild boar meat and reduce the risk of toxoplasmosis transmission. Further research is recommended to investigate T. gondii distribution in other tissues, including the brain, and to better understand the parasite's epidemiology in this region.

Rabies vaccination in domestic dog populations has increased globally in a bid to protect human health. Surveillance efforts, however, are inconsistent in endemic regions such as in sub-Saharan Africa, due to fragmented reporting and limited diagnostic capacity for suspected cases, limiting successful monitoring and evaluation of vaccination campaigns. Here, we conducted a pilot study aiming to strengthen rabies surveillance by combining community-based surveillance with field-based diagnostic testing in pastoral and agro-pastoral communities in central Kenya; communities which are frequently marginalised from health systems. During the 6-month pilot study, there were 14 alerts of suspected rabid dogs in the community, of which eight were tested and five diagnostically confirmed as rabid. Two positive samples processed successfully for whole genome sequencing indicated that the rabies variant circulating in central Kenya during the study period belonged to the Africa 1b subclade, which is similar to variants identified in eastern Kenya and Tanzania, suggesting regional transmission. This pilot study indicates that rabies continues to circulate in the region and that community-based surveillance, when combined with enhanced diagnostic testing, can help alleviate underreporting and guide vaccination campaigns.

Aims: The world experienced a huge number of outbreaks of highly pathogenic avian influenza (HPAI) in birds, which could represent one of the largest registered epidemics of infectious disease in food-producing animals. Therefore, mammals, including humans, are continuously exposed to HPAI viruses leading to sporadic and sometimes unusual mammal infections. The aim of this paper is to assess the risk of crossing the avian/mammalian species barrier by the currently circulating HPAI viruses, focusing on the epidemiological situation of Belgium, a representative country for Western Europe.

Methods and results: Information on transmission pathways and species susceptibility, based on the experimental and epidemiological data, was reviewed and weighted to assess the risk of mammal infection with HPAI A(H5N1) viruses of the circulating clade 2.3.4.4b. This risk is defined as the likelihood of mammal infection by birds crossed by the clinical consequences of this infection for this animal. From the Belgian perspective, it is concluded that this risk remains 'low' to 'moderate' for captive/domestic mammal species. However, this risk was categorised as 'high' for certain species, i.e. mammals that have the opportunity to have frequent direct or indirect close contacts with infected (dead) birds, such as wild felids, wild mustelids, foxes and wild marine carnivore mammals. For some mammal species, the uncertainty associated with the assessment remains high due to an ever-changing situation.

Conclusions: The longer the virus will continue to circulate in wildlife/the environment the stronger the probability of contact between infected birds and mammals will become. This will increase the related risk of viral adaptation for efficient transmission between mammal, posing concerns for public health. Regular reassessments based on the field and experimental data are therefore necessary to implement and adapt risk-based mitigation measures. This will require continuous monitoring of avian influenza viruses in both birds and mammals as well as sharing of sequence data.

Background: In Latin America, there is a high incidence of vampire bat-transmitted rabies in cattle causing increased mortality of livestock, which heavily impacts the agricultural sector. Anticoagulants-based control methods for the common vampire bat (Desmodus rotundus) have been employed continuously since the 1970s with various methods of application, presentations, doses and active ingredients. Studies from half a century ago still serve as a reference for the current use of anticoagulants for bat-borne rabies control in Latin America. The objective of this study was to structurally and bibliometrically review literature on the use of anticoagulants for the control of D. rotundus as a means of rabies control.

Materials & methods: Scientific literature on the use of anticoagulant products for D. rotundus control was obtained, reviewed and analysed. Articles were retrieved from Scopus and Web of Science databases. Research articles from 1971 to 2021 in Spanish, English and Portuguese were included in the review. Results were visualised using RStudio, Bibliometrix and VOSviewer.

Results: The body of literature indicates effectiveness of up to 100% in the use of anticoagulants to induce bat mortality. The effectiveness of anticoagulants for rabies control, however, remains uncertain. No evidence was found to support or refute the use of anticoagulants for rabies control.

Discussion: Instead, literature suggests that disturbing bat colonies increases rabies prevalence. This finding suggests that anticoagulants may have the opposite intended effect on rabies control and highlights the importance of further research on the practical methods for bat-borne rabies prevention.

Conclusion: Field experimental studies that include control groups over areas and periods that account for D. rotundus ecology are needed to determine the effectiveness of anticoagulants for rabies control in livestock. In conclusion, the use of anticoagulants for rabies control is questionable.

Introduction: In Brazil, the emergence of feline sporotrichosis, a neglected subcutaneous mycosis primarily transmitted by cats and caused by the fungus Sporothrix brasiliensis, has been monitored via molecular tools. This approach underscores the geographic expansion of this disease and highlights the critical role of molecular surveillance in understanding its epidemiology and guiding public health interventions.

Methods: We investigated three domestic cats (Felis catus) with multiple skin lesions in Picos, Piauí, Brazil. The cats were examined, and samples were collected for laboratory diagnosis, including cytological evaluation, fungal culture, and molecular characterisation. The molecular analysis involved a one-tube multiplex probe-based qPCR assay for the diagnosis of Sporothrix species, mating-type determination, and amplified fragment length polymorphism (AFLP, EcoRI-GA/MseI-AG) to assess genetic similarity and potential origin.

Results: All three cats were diagnosed with sporotrichosis caused by the hypervirulent S. brasiliensis. A probable case of zoonotic transmission has been reported in a 12-year-old girl who developed Parinaud oculoglandular syndrome after contact with one of the cats with sporotrichosis. The molecular analysis revealed that the cat isolates were MAT 1-2 and formed a single cluster according to the AFLP analysis, suggesting direct transmission (cat-cat) and a potential founder effect. The isolates were also closely related to strains from Pernambuco and Southeast Brazil, indicating a possible introduction from these regions.

Conclusions: Identifying S. brasiliensis in Piauí emphasises the need for increased awareness and control measures to prevent further spread. The predominance of the MAT1-2 idiomorphs and the genetic similarity among outbreak isolates suggest clonal expansion, which could have significant implications for public health and veterinary practices. Considering its zoonotic potential and environmental adaptability, a One Health approach is crucial for managing and controlling the spread of cat-transmitted sporotrichosis.

Introduction: Judicious antimicrobial use is essential for the continued treatment of infections in small and mixed animal veterinary medicine. To better support Washington (WA) State veterinarians in antimicrobial stewardship, we surveyed licensed small and mixed animal veterinarians and led group conversations regarding antimicrobial prescription practices.

Methods: Survey questions included demographic information, factors influencing prescription practices and clinical cases. Responses were summarised and logistic regressions were performed to identify factors associated with antibiotic treatment choices. Group conversations, led by a licensed veterinarian, focused on resource gaps for veterinarians, management of clinical scenarios and interpretation of minimum inhibitory concentrations (MICs) and breakpoints. A systematic qualitative analysis of conversation transcripts identified key themes such as common barriers to stewardship.

Results: Among 53 responses to clinical scenarios, veterinarians selected the most appropriate treatment choice, according to a veterinary microbiologist, 62% of the time. Variability was observed in culture and susceptibility practices and antibiotic choices. Survey respondents reported an influence of the client ability to medicate (92%), considerations of resistance (91%), client finances (75%) and availability of antimicrobials (75%) on their prescription decisions. There were no significant associations between opinions about contributing factors to antimicrobial resistance (AMR) or guidelines used and treatment choices in clinical scenarios. Among 15 veterinarians interviewed in group conversations, a systematic qualitative analysis of conversation transcripts revealed key themes, including reliance on human medicine as a resource and a lack of support for veterinarians in interpreting MICs and breakpoints.

Conclusions: The variability in veterinary antibiotic treatment decisions in this study suggests a need for further dissemination of standardised antimicrobial stewardship resources for veterinarians. Client-related challenges and the cost of culture and susceptibility are major barriers to stewardship. To address these barriers, it is necessary to provide standardised, easy-to-access guidance for veterinarians in interpreting MICs and breakpoints, as well as develop antimicrobial use resources for clients.

Introduction: Aedes-borne diseases, such as Zika and Chikungunya, originate from an enzootic cycle in which non-human primates (NHPs) function as reservoirs. This study aimed to analyze the characteristic habitat and ecological niche models of Aedes albopictus within the confines of a Primate Research Center (PRC), to assess its potential as a site for zoonotic arbovirus transmission. Additionally, this study aimed to construct a comprehensive map to delineate the risks of arbovirus transmission.

Methods: A 1-year direct field survey was conducted from January to December 2022 in the PRC to obtain comprehensive data on the presence of larvae, including their conditions, habitat types, and physicochemical characteristics. Larval collection was meticulously performed at potential breeding sites using a 350 ml dipper and pipette. Information on the ecological niche was compiled based on a combination of general environmental variables and mosquito presence data obtained from direct field surveys using the Maximum Entropy (MaxEnt) model.

Results: In total, 120 presence points for Ae. albopictus larvae were obtained from the PRC area, with 23.02% of the larvae found in buckets as artificial habitats, and 18.25% found in bromeliad plants as natural habitat types. Larvae of Ae. albopictus occupy artificial habitats that are not turbid, exposed to direct sunlight, and devoid of predators. The abundances and occurrences of Ae. albopictus larvae was found to be significantly influenced by pH and total dissolved solids. This study showed that the PRC was a suitable habitat for breeding Ae. albopictus larvae, with the distance to buildings emerging as a significant environmental variable in the species distribution model CONCLUSIONS: The fine-scale empirical model developed for Ae. albopictus and its habitat characteristics not only provide insights into the suitability of vector habitats, but can also be used assess the risk of arbovirus transmission, potentially informing strategies for controlling mosquito breeding sites within the PRC.

Introduction: Leptospira spp. is a bacterial genus which includes pathogenic species that causes leptospirosis. Several animal species can harbour, shed and disseminate the bacteria through their urine. Although the circulation of Leptospira among homeless dogs may be common, the presence of Leptospira among household dogs is more important since they can act as important sources of infection for their owners due to the closer contact with humans.

Aim: The aim of the present study was to detect the presence of Leptospira spp. among household dogs from 15 municipalities of the Caldas department.

Methods: Between November 2015 and January 2017, an active household dog sampling was performed in 15 municipalities of Caldas department. Dog blood samples were tested through conventional PCR targeting a fragment of the Leptospira rrs and LipL32 genes. All obtained amplicons were purified and bi-directionally sequenced. Obtained sequences were assembled and edited for subsequent phylogenetic analysis.

Results: A total of 196 dogs were sampled from 15 municipalities of Caldas department, of which 180 were screened for Leptospira spp. Ten (5.6%) dog blood samples from seven municipalities were successfully amplified for the Leptospira rrs gene. Two Leptospira rrs good-quality sequences were obtained which had a closer relationship with Leptospira interrogans and Leptospira santarosai.

Conclusion: We confirm the presence of Leptospira spp. closely related with L. interrogans and L. santarosai among household dogs from seven municipalities of Caldas department. These results highlight the need to improve the care of household dogs in Caldas department since they could eventually become important sources of infection of leptospirosis.

Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has the potential to infect various animals, including domestic pets like dogs and cats. Many studies have documented infection in companion animals by molecular and serological methods. However, only a few have compared seroprevalence in cats and dogs from the general population, and these studies were limited by small sample sizes and collections over short periods. Our aim was to obtain a more accurate evaluation of seroprevalence in companion animals in France and to determine whether cats and dogs differ in their exposure to SARS-CoV-2.

Methods: We conducted an extensive serological survey of SARS-CoV-2, collecting blood samples from 2036 cats and 3577 dogs during routine veterinary medical examinations across different regions of metropolitan France from October 2020 to June 2021. This period encompassed the peaks and onset of two waves, as well as the emergence of the first variants. A microsphere immunoassay targeting the receptor-binding domain and trimeric spike protein was used to detect anti-SARS-CoV-2 antibodies. A subset of 308 seropositive samples was tested for the presence of neutralising antibodies.

Results: We determined an overall seroprevalence of anti-SARS-CoV-2 antibodies of 7.1% (95% confidence interval [CI]: 6.4%-7.8%) among the sampled pets. Cats exhibited a significantly higher seroprevalence (9.3%; 95% CI: 8.1%-10.1%) compared to dogs (5.9%; 95% CI: 5.2%-6.8%). Among the subset of seropositive samples, 81 (26.3%; 95% CI: 21.5%-31.6%) displayed neutralizing antibodies. Furthermore, seroprevalence in both species was lower in older animals and was not associated with sex. Finally, unlike cats, seroprevalence in dogs was found to be correlated with the date of sampling.

Conclusions: The large sample size enhances the reliability and statistical robustness of our estimates regarding pet exposure to SARS-CoV-2. This study on SARS-CoV-2 reaffirms the crucial importance of adopting a One Health approach incorporating domestic animals when managing an epidemic caused by a zoonotic virus.