Zoonotic Diseases

Viral zoonoses represent a critical intersection of global health, ecology, and ethical issues. Pathogens that pass from animals to humans. This review examines the complex landscape of viral zoonoses, including their mechanisms, impact, and mitigation strategies. We begin with insights into the historical context and significance of these diseases and then explore spillover mechanisms influenced by genetic, ecological, and anthropogenic factors. This review covers the host range, transmission dynamics, and immunological barriers, including viral detection, adaptation, and immune evasion. Genomic insights have revealed the genetic determinants of host switching and adaptation, illuminating the dynamics of viral spillover events. We emphasize the anticipation and prevention of zoonotic events, highlighting surveillance, early warning systems, and the “One Health” approach. Using case studies of outbreaks such as Ebola, avian influenza, and COVID-19, this review examines the real-world consequences of zoonotic diseases. We then discuss interventions, including mitigation strategies and vaccination, and their ethical and social implications. Drawing on past outbreaks, we provide recommendations for the future, aiming to balance human health, conservation, and animal welfare. This review aims to inform professionals, academics, and policymakers by offering a multidisciplinary perspective on the complex world of viral zoonoses and strategies to protect global health. Full article

Our article presents a holistic analysis aimed at discerning patterns from ancient–modern comparative contexts of malaria. The article’s interdisciplinary and consilient methodology is drawn from a range of disciplines: the humanities and social sciences, medical knowledge (particularly epidemiology and pathology), molecular phylogenetics, demography, archaeology, paleopathology, numismatics, complex systems theory, etc. The article begins with a detailed exploration of a 463 BCE epidemic event that likely marked the, ultimately transformative, debut of P. falciparum evolutionary lineage malaria for ancient Roman civilization. It is important to note that the concept of evolutionary lineage is defined herein as a sequence of organisms, descended from a common ancestor and culminating, for the present at least, in the form existing currently. An interdisciplinary retrospective diagnosis methodology is utilized to establish, with what we believe to be a high degree of probability, a conclusion that effectively marks the beginning point for the ancient side of our comparative example. The deep interdisciplinary/historical methods used to elucidate the ancient side of the disease equation both lead to a clear conclusion and suggest potential modern analogies or even “prophecies.” These are used to highlight the threats emanating from the current spread of zoonotic P. knowlesi malaria in Southeast Asia. The article also utilizes six broader holistic and interdisciplinary factors in its contextual and comparative analysis: (A) political, military and security contexts; (B) the effects of cultural perceptions; (C) the role of climate and climate change; (D) additional anthropogenic environmental factors; (E) perceptions, practices and capabilities of prevailing medical systems and (F) holistic underlying states of the health of affected populations. Full article

Campylobacter spp. are significant zoonotic pathogens, increasingly recognized for their role in the transmission of antimicrobial resistance (AMR) between animals and humans. This study aims to determine the occurrence, antimicrobial resistance profiles, and characterization of multidrug resistance indices of Campylobacter spp. isolated from domestic pets in Kelantan, Malaysia. Methods: Rectal swabs (n = 150) were collected from both healthy and diarrheic cats. Campylobacter spp. were isolated and confirmed by PCR, and antimicrobial susceptibility was assessed using the disk diffusion method. Results: Campylobacter spp. were detected in 35.3% of cats (53/150; SE = 0.04; 95% CI: 28.1–43.3%), with C. upsaliensis identified as the predominant species (33.3%; SE = 0.05; 95% CI: 24.5–43.6%), followed by C. jejuni (17.8%; SE = 0.04; 95% CI: 11.3–26.9%) and C. coli (7.8%; SE = 0.03; 95% CI: 3.8–15.2%). Isolates exhibited high resistance rates to amoxicillin (90.6%), ampicillin (81.1%), tetracycline (67.9%), erythromycin (62.3%), and sulphonamides (54.7%). Conclusion: The study reveals a substantial prevalence of Campylobacter spp. and notable levels of antimicrobial resistance among feline isolates, highlighting the zoonotic threat in Malaysia. These findings emphasize the importance of integrated surveillance and prudent antimicrobial stewardship under a One Health framework. Full article

Viral zoonoses or viral pathogens transmitted from animals to humans—constitute a rapidly intensifying global health and economic challenge. They are responsible for an estimated 2.5 billion illnesses and 2.7 million deaths annually, representing nearly 60% of all infectious diseases and 75% of newly emerging infections. Recent outbreaks, including Coronavirus disease 2019 (COVID-19), Ebola, Nipah, and avian influenza, underscore their capacity to overwhelm health systems, with COVID-19 alone projected to reduce global Gross Domestic Product by USD 22 trillion by 2025 and impose annual healthcare costs of USD 2–3 trillion. Beyond mortality and morbidity, zoonotic events disrupt trade, depress rural livelihoods, and inflict agricultural losses exceeding USD 100 billion per outbreak, with impacts disproportionately borne by low- and middle-income countries. Hotspot regions across tropical North and South America, Asia, and Central Africa remain especially vulnerable due to accelerating land use change, climate variability, and intensified wildlife–human interfaces. While the Global One Health Index highlights high regional heterogeneity, with sub-Saharan Africa scoring lowest, a critical gap persists between the conceptual strength of One Health and its operationalization in resource-limited settings. This review synthesizes evidence on drivers, clinical manifestations, and socioeconomic burdens of viral zoonoses, while highlighting novel perspectives on equity gaps, co-infection dynamics, and limitations of global preparedness initiatives. We argue that current strategies remain over-reliant on donor-driven agendas and insufficiently integrated across sectors. Addressing future zoonotic threats requires prioritizing surveillance in high-risk geographies, integrating epidemiological and economic data for preparedness planning, and supporting context sensitive One Health approaches that confront political, financial, and structural barriers to implementation. Full article

Influenza A viruses (IAVs) primarily cause respiratory illness but can also induce extrapulmonary effects, which may be aggravated by obesity. This study evaluated the impact of obesity on virus replication, histopathological changes, and cytokine/chemokine profiles in extrapulmonary sites during the acute phase, following a high-dose IAV infection. Diet-induced non-obese mice or mice with obesity were inoculated intranasally with either vehicle (medium) or 10³ TCID₅₀ of the 2009 pandemic H1N1 IAV. At 3 days post-infection (dpi), the lungs, blood, and various extrapulmonary tissues were collected for virus titration, histopathological analysis, and cytokine/chemokine quantification. IAV infection resulted in comparable virus titers (6–7 log₁₀ TCID₅₀/mL) and histopathological scores (p > 0.05 in each case) in the lungs of mice with or without obesity. Replicating viruses were not detected in the extrapulmonary sites, and histopathological scores did not differ significantly between the two groups. However, analysis of fold changes in five cytokines/chemokines (i.e., IL-6, IL-1β, TNFα, MCP-1, and IFNγ) revealed site-specific differences. IL-6 was significantly higher (p < 0.05) in the lungs and perirenal adipose tissue, and showed a higher trend in the kidney (0.05 ≤ p ≤ 0.1); IL-1β had a higher trend in the lungs; TNFα was significantly lower in the kidney but showed a higher trend in the lungs; while MCP-1 was significantly lower in the lungs, plasma, and inguinal adipose tissue of mice with obesity compared to non-obese mice. Future studies should consider a broader range of IAV strains/subtypes, doses, time points, and inflammatory markers to better understand how obesity affects extrapulmonary outcomes. Full article

The Marburg virus (MARV) is a zoonotic pathogen that causes a high case fatality rate of up to 100% in humans. In response to Marburg virus disease (MVD) outbreaks in the Kagera region, an ecological investigation was initiated to map the population and ecological threat to the reservoir host of MARV: Egyptian fruit bats. The investigation conducted from October 2023 to December 2024 included interviews with local authorities to locate all known autochthonous bat colonies in the region. Bat species confirmation was performed using high-resolution melting analysis (HRMA) and DNA barcoding, targeting two mitochondrial genes: cytochrome oxidase 1 (COI) and 16S rRNA. We found five considerably large cave-dwelling Egyptian fruit bat colonies (with approximately 100,000 individuals) at the geolocations between 1°06′04.2″ and 2°26′35.8″ S latitude and 30°40′49.7″ and 31°51′19.8″ E longitude. The study also provides the first confirmed identification of Egyptian fruit bats (Rousettus aegyptiacus) (accession numbers: PV700530-PV700534) in major bat colonies in the Kagera River Basin ecosystem. Cave-dwelling Egyptian fruit bats in mines face higher risks, and thus, attention is needed to prevent this species from becoming more vulnerable to extinction. The loss of bat roosting sites and subsequent population declines are primarily driven by the destructive practice of burning car tyres and logs, a method used to eliminate colonies through toxic smoke and heat. The collection of guano and partially eaten fruits in mining caves, as well as daily contact with Egyptian fruit bats in mines, homes, and churches, have become major potential risk factors for MARV transmission to humans. Increased threats to bats in the Kagera region warrant the implementation of conservation strategies that ensure the survival of the bat populations and inform policies on MVD risk reduction in Tanzania and the broader East African region. Full article

Background: Zoonotic fascioliasis and schistosomiasis, caused by trematode parasites transmitted by freshwater snails, are neglected tropical diseases of both medical and veterinary importance. There are critical knowledge gaps regarding the transmission dynamics of these infections in humans and animals, particularly in endemic African communities. Therefore, the current study aimed to determine the burden of human zoonotic schistosomiasis and fascioliasis among different age groups, focusing on the Lake Victoria zone and the Southern Highlands of Tanzania. Methods: A cross-sectional study was conducted among preschool-aged children, school-aged children, and adults. A total of 1557 stool and urine samples were collected, 400 from preschool children, 804 from school-aged children, and 353 from adults. Stool samples were processed using the Kato–Katz technique and the formol-ether concentration method to detect Schistosoma mansoni and Fasciola spp., respectively. Urine samples were examined for Schistosoma haematobium infection using the urine filtration method. Data were analyzed using Stata version 17. The t-tests or one-way ANOVA were used to assess statistical differences in the mean egg counts of S. mansoni and S. haematobium between exposure groups. Results: The overall prevalence of S. haematobium was 4.9%, S. mansoni was 1.2% with no significant differences across age groups, but with a statistically significant difference between sexes 1.8%. Males had a higher prevalence of both S. haematobium and S. mansoni infections compared to females. The prevalence of Fasciola infection was 0.9%, with the highest prevalence found in adults (≥18 years). Conclusions: Zoonotic schistosomiasis and fascioliasis are prevalent in the study area, affecting individuals across all age groups. This is the first study to report the presence of Fasciola infection in both the Lake Victoria zone and the Southern Highlands of Tanzania. These findings call for the Ministry of Health, through the Tanzania NTD Control Program, to recognize fascioliasis as a high-priority disease and include it in the national master plan. Full article

Brazil is the first of the 12 priority countries in Latin America with the highest number of cases of American cutaneous leishmaniasis (ACL). This study estimated the prevalence of ACL in Brazil and classified the states according to the different levels of endemicity in the period from 2014 to 2024. This is a retrospective and cross-sectional study of ACL cases registered in Brazil by the Information System for Notifiable Diseases of the Ministry of Health. The predominant cases were male (73.2%), brown (65.0%), aged between 20 and 39 (41.5%), with a low level of education (44.4%), 0.5% in pregnant women, 80% of cases were confirmed by laboratory criteria, and 90% were classified as cutaneous. A total of 182,072 autochthonous cases were recorded, with a prevalence of 89.6 cases per 100,000 population. Two states were classified as having high intense endemicity; three were classified as having medium intense endemicity; four were classified as having low intense endemicity; five states were classified as having moderate endemicity; and 13 were classified as having low endemicity. The municipality of Presidente Figueiredo, Amazonas, had the highest prevalence of ACL (5503.1%), while Belo Horizonte had the lowest prevalence (72.2%). The month with the highest average number of cases was January with 1731 (with a standard deviation of 364; upper limit of 1933; lower limit of 1572). The heterogeneity of endemicity among States suggests that social and environmental determinants influence the dynamics of ACL transmission. All sociodemographic, clinical, and epidemiological categories, when compared with the different levels of endemicity, showed significant effects (p < 0.05), except for the variable gestational status in high disease endemicity. The inclusion of these variables significantly improved the model’s ability to predict the dependent variable. Full article

Mpox has re-emerged as a global public health threat, particularly in endemic regions such as Nigeria, where human, animal, and environmental health sectors intersect. To inform surveillance and control strategies, this study assessed the knowledge, attitudes, and practices (KAP) toward Mpox among One Health stakeholders in Nigeria. A cross-sectional survey was conducted among 492 participants from human, veterinary, and environmental health sectors using a structured questionnaire. Descriptive statistics, ordinal logistic regression, and margins analysis were used to evaluate levels and predictors of KAP. Results showed that 33.7% of respondents had low knowledge, 43.5% moderate, and 22.8% high. While 62.6% demonstrated high attitude scores, only 48.2% reported moderate preventive practices. Gender was significantly associated with attitudes, with females having lower odds of expressing higher attitudes than males (OR = 0.70, 95% CI: 0.49–1.00, p = 0.052), and margins analysis revealed a predicted probability of high attitude at 56% for females and 64% for males. Multivariable modeling for practice was not pursued because model fit did not improve compared to univariable results, and sparse data led to unstable estimates, thus offering no added explanatory power. These findings underscore persistent knowledge gaps and gender-related disparities that may hinder effective Mpox response. Targeted risk communication and capacity building are recommended to strengthen One Health preparedness in Nigeria. Full article

Brucella canis is a neglected zoonotic pathogen associated with canine reproductive disorders and emerging public health concerns. This study presents the first nationwide systematic review and meta-analysis of Brucella spp. in Portugal, integrated with a 13-year retrospective seroepidemiological investigation (2013–2025) of B. canis in dogs across mainland Portugal and Insular Autonomous Regions. Among 132 canine serum samples, a seropositivity of 23.48% was observed using an immunochromatographic assay confirmed by indirect immunofluorescence (IFAT). Significant associations were identified with seasonality (p < 0.001) and breed (p = 0.001), while sex and age were not statistically significant. Municipal-level analysis revealed marked heterogeneity, with Trofa showing the highest seropositivity (58.82%) and a pooled odds ratio of 11.28 (95% CI: 2.90–43.94; p < 0.001). In parallel, meta-analyses of published data estimated a pooled seroprevalence of 2.42% in animals (95% CI: 1.79–3.13) and 10.57% in humans (95% CI: 8.80–12.47), underscoring the broader burden of Brucella spp. exposure in Portugal. These findings suggest underdiagnosis of canine brucellosis and highlight the need for enhanced surveillance in high-risk breeds and regions. The study reinforces the importance of integrated One Health strategies to improve early detection, control, and prevention of B. canis infection in both veterinary and public health contexts. Full article

Rickettsia parkeri strain Atlantic rainforest is an emerging pathogen in Brazil, but human infections remain rarely reported. We report the first confirmed case in the municipality of Caraguatatuba on the northern coast of São Paulo State, Brazil. A 37-year-old man was bitten by an Amblyomma ovale tick while visiting a forested area. Six days later, he developed a papular skin lesion with a necrotic center at the tick bite site, accompanied by regional lymphadenopathy, myalgia, and flu-like symptoms. Ticks parasitizing both the patient and his dog were collected, along with the eschar. Two ticks were analyzed for Rickettsia isolation, and R. parkeri was successfully isolated from one infected specimen. The patient’s infection was confirmed by molecular testing through the PCR amplification of the gltA and ompA genes from an eschar inoculation sample. This represents the sixth confirmed case of rickettsiosis caused by R. parkeri in Brazil, and it reinforces the need for increased epidemiological surveillance in endemic regions for spotted fever caused by this pathogen. With the increasing recognition of R. parkeri in South America, further research is needed to better understand its transmission dynamics, clinical manifestations, and potential public health impact. Full article

Although trap-neuter-return (TNR) is a popular method for managing free-roaming domestic cat populations, a common criticism is that sterilization fails to mitigate the public health risks posed by free-roaming cats. One of these risks is the environmental contamination of Toxoplasma gondii, a parasite that can be spread in the feces of actively infected felids (both domestic and wild). In healthy humans, toxoplasmosis tends to be mild or asymptomatic; however, the disease can have severe consequences (e.g., for pregnant women) and even be fatal in immunocompromised individuals. Previous research has examined the extent to which free-roaming domestic cats might contaminate sites frequented by young children (e.g., schools and parks). However, the model used included several assumptions that are not reflective of sterilized cats in an urban setting (e.g., smaller home range). By properly accounting for several key factors (e.g., reproductive status, home range), our modeling revealed considerably lower rates of potential incursions by sterilized free-roaming cats than those reported previously. More importantly, our results show that sterilization contributes to a considerable reduction in the risk of environmental contamination; TNR therefore appears to be a valuable harm reduction strategy in mitigating the risks of T. gondii infection. Full article

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) raced around the world across different populations; there needs to be a consolidated effort to understand the divergence of the epidemiology of SARS-CoV-2. Population-based epidemiological characteristics studies measure the extent of SARS-CoV-2 infection in a country. The current research study was designed to report epidemiological data from Pakistan. For this purpose, 246 SARS-CoV-2-infected patients were included in the study. For SARS-CoV-2 confirmation, viral samples were collected from all the study participants; SARS-CoV-2 infection was confirmed by viral nucleic acid detection using a nucleic acid detection kit. After SARS-CoV-2 confirmation, all the study participants were interviewed for epidemiological data through a detailed questionnaire. The study results showed that the disease ratio was higher between 30 and 59 years (51.21%) of age. The male ratio (55.28%) was higher compared to the female ratio (44.71%). The patients’ illiteracy and low socioeconomic status were 32.52% and 59.75%, respectively. The majority of the patients (97.56%) had cough, smell or taste disturbance (79.67%), or fever (76.42%), and 70.73% had fatigue. For comorbidities, a higher ratio was observed for diabetes (38.61%), hypertension (36.17%), and respiratory disease (16.26%). The vaccination status analysis revealed that 51.21% of patients had not received routine immunizations, and 65.5% were un-vaccinated against SARS-CoV-2. Notably, not a single patient was vaccinated for influenza vaccine. The current research study concluded that SARS-CoV-2 was more prevalent in individuals who were middle aged, male, and had low socio-economic status. The most common symptoms were cough, smell or taste disturbance, and fever. The patients’ vaccination status highlights a critical gap in preventive healthcare and shows the need to strengthen vaccination awareness and accessibility in the population to reduce vulnerability to future outbreaks. Future research should focus on investigating the impact of COVID-19 outcomes on comorbidities such as diabetes and hypertension. Full article

The 2025 avian influenza A(H5N1) outbreak has highlighted the urgent need for rapidly generated health communication materials during public health emergencies. Artificial intelligence (AI) systems offer transformative potential to accelerate content development pipelines while maintaining scientific accuracy and impact. We evaluated an AI-generated health communication material on bird flu precautions among 100 U.S. adults. The material was developed using ChatGPT for text generation based on CDC guidelines and Leonardo.AI for illustrations. Participants rated perceived message effectiveness, quality, realism, relevance, attractiveness, and visual informativeness. The AI-generated health communication material received favorable ratings across all dimensions: perceived message effectiveness (3.83/5, 77%), perceived message quality (3.84/5, 77%), realism (3.72/5, 74%), relevance (3.68/5, 74%), attractiveness (3.62/5, 74%), and visual informativeness (3.35/5 67%). Linear regression analysis revealed that all features significantly predicted perceived message effectiveness in unadjusted and adjusted models (p < 0.0001), e.g., multivariate analysis of outcome on perceived visual informativeness showed β = 0.51, 95% CI: 0.37–0.66, p < 0.0001. Also, mediation analysis revealed that visual informativeness accounted for 23.8% of the relationship between material attractiveness and perceived effectiveness. AI tools can enable real-time adaptation of prevention guidance during epidemiological emergencies while maintaining effective risk communication. Full article

Knowing the specific characteristics and animal tuberculosis risk factors present and applying good practices are crucial points in combating tuberculosis (TB) in a Mediterranean multi-species scenario. The objective of this work is to statistically analyze the association between the existence of TB in areas with a marked game–livestock interface, with various complementary factors found in 30 extensive farms in southern Portugal, such as the number of animals of each large game species present in the territory and the frequency of their sightings. Collecting this information, an inferential statistical analysis was conducted to obtain information on the association type between TB occurrence in the farms and the presence of highlighted factors. The main statistical results show an association between the presence of large game species and TB occurrence in the analyzed areas. Thus, in a multi-species scenario, large game species are a crucial component in TB maintenance, namely when stricter contact occurs. This could be one of the reasons why TB continues to circulate and why the eradication process is so difficult; the risk of zoonotic transmission is evident. It is crucial to apply biosecurity tools to improve the alignment and structure of natural resource management strategies. Full article

In Kenya, Rift Valley fever (RVF) outbreaks pose significant challenges, being one of the most severe climate-sensitive zoonoses. While machine learning (ML) techniques have shown superior performance in time series forecasting, their application in predicting disease outbreaks in Africa remains underexplored. Leveraging data from the International Livestock Research Institute (ILRI) in Kenya, this study pioneers the use of ML techniques to forecast RVF outbreaks by analyzing climate data spanning from 1981 to 2010, including ML models. Through a comprehensive analysis of ML model performance and the influence of environmental factors on RVF outbreaks, this study provides valuable insights into the intricate dynamics of disease transmission. The XGB Classifier emerged as the top-performing model, exhibiting remarkable accuracy in identifying RVF outbreak cases, with an accuracy score of 0.997310. Additionally, positive correlations were observed between various environmental variables, including rainfall, humidity, clay patterns, and RVF cases, underscoring the critical role of climatic conditions in disease spread. These findings have significant implications for public health strategies, particularly in RVF-endemic regions, where targeted surveillance and control measures are imperative. However, this study also acknowledges the limitations in model accuracy, especially in scenarios involving concurrent infections with multiple diseases, highlighting the need for ongoing research and development to address these challenges. Overall, this study contributes valuable insights to the field of disease prediction and management, paving the way for innovative solutions and improved public health outcomes in RVF-endemic areas and beyond. Full article

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne disease caused by the SFTS virus (SFTSV). A rapid and cost-effective point-of-care testing detection system is important for the early diagnosis of SFTS. Herein, we developed a ready-to-use dried reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for the direct detection of SFTSV in clinical samples. The assay enables simple, RNA-extraction-free detection using heat-treated serum or plasma, followed by a 30 min incubation at 65 °C. The results are visually interpreted through the color emitted, which can be observed under LED light. The established assay demonstrated detection sensitivity for SFTSV at 10⁴ copies/µL and was effective in identifying infections in cats. Despite being less sensitive than real-time RT-PCR, this dried RT-LAMP method offers a rapid, cost-effective alternative suitable for point-of-care use, particularly in remote or resource-limited settings. The simplified workflow and visual readout make it a practical tool for the early detection and daily surveillance of SFTSV in animals. Full article

In the wake of the COVID-19 pandemic and amid growing concerns regarding viral threats such as avian influenza, Mpox, and HKU5 bat coronaviruses, the phenomenon of viral zoonotic spillover, when viruses leap from circulation in non-human animals to humans, has garnered unprecedented global attention [...] Full article

Zoonotic diseases are a persistent public health concern, especially in low- and middle-income countries like Brazil. This cross-sectional study evaluated the knowledge and perceptions of 132 high school students (70 public and 62 private) in Goiânia, Brazil, regarding zoonoses, using a structured questionnaire. Statistical analyses (Chi-square and Fisher’s exact tests) revealed significant differences (p < 0.05) between public and private school students in knowledge levels, pet care practices, and the awareness of zoonotic risks. While pet ownership was common in both groups, only 53% of private and 21% of public school students correctly defined “zoonosis.” Rabies, taeniasis, leptospirosis, tuberculosis, cysticercosis, cutaneous larva migrans, and leishmaniasis were the most frequently cited diseases, with private school students demonstrating greater recognition across all categories. However, most participants lacked detailed knowledge about transmission routes and prevention. Misconceptions—such as zoonoses affecting only low-income populations—were also identified. Preventive actions like sanitation, public education, and vaccination were commonly suggested but not consistently linked to zoonoses. These findings highlight critical educational gaps and emphasize the need to incorporate One Health principles into school curricula to improve youth understanding and support public health strategies for zoonosis prevention. Full article