The macroecology of infectious diseases: a new perspective on global-scale drivers of pathogen distributions and impacts.

Identifying drivers of infectious disease patterns and impacts at the broadest scales of organisation is one of the most crucial challenges for modern science, yet answers to many fundamental questions remain elusive. These include what factors commonly facilitate transmission of pathogens to novel host species, what drives variation in immune investment among host species, and more generally what drives global patterns of parasite diversity and distribution? Here we consider how the perspectives and tools of macroecology, a field that investigates patterns and processes at broad spatial, temporal and taxonomic scales, are expanding scientific understanding of global infectious disease ecology. In particular, emerging approaches are providing new insights about scaling properties across all living taxa, and new strategies for mapping pathogen biodiversity and infection risk. Ultimately, macroecology is establishing a framework to more accurately predict global patterns of infectious disease distribution and emergence.

Epidemiology of marine turtle fibropapillomatosis and tumour-associated chelonid alphaherpesvirus 5 (ChHV5; Scutavirus chelonidalpha5) in North-Western Mexico: a scoping review implementing the one health approach.

Fibropapillomatosis (FP) - tumour-associated chelonid alphaherpesvirus 5 (ChHV5; Scutavirus chelonidalpha5) - is a disease that affect marine turtles around the world, and characterized by the formation of cutaneous tumours that can appear anywhere on the body. We carried out a thorough literature search (from 1990 to 2024) in the feeding sites of North-western Mexico, a region that hosts important habitats for feeding, development, and reproduction for five of the seven existing sea turtle species. We found 18 reports recording a total of 32 cases of FP and/or ChHV5/Scutavirus chelonidalpha5 in coastal and insular areas of North-western Mexico. Baja California Sur resulted with the highest number of cases (75%). While the first case of ChHV5/Scutavirus chelonidalpha5 infection was reported in 2004, the presence of FP tumours was reported in 2014 and became more frequent between 2019 and 2024. The affected species were black, Chelonia mydas (50%), olive ridley, Lepidochelys olivacea (46.8%) and loggerhead turtles, Caretta caretta (3.2%). Tumours occurred mainly in anterior flippers (46.1%) and neck (22.5%), and most had a nodular and verrucous appearance with a rough surface. In the study region, there is a potential sign of the emergence of the ChHV5/Scutavirus chelonidalpha5 infections and FP disease during the last 20 years, with a rapid increase during the last 10 years. As long as infections by ChHV5/Scutavirus chelonidalpha5 and the prevalence of the FP disease may be potentially influenced by anthropogenic activities, a One Health approach is needed to understand and improve sea turtles' health.

Metabolomic profiling implicates mitochondrial and immune dysfunction in disease syndromes of the critically endangered black rhinoceros (Diceros bicornis).

The critically endangered black rhinoceros (Diceros bicornis; black rhino) experiences extinction threats from poaching in-situ. The ex-situ population, which serves as a genetic reservoir against impending extinction threats, experiences its own threats to survival related to several disease syndromes not typically observed among their wild counterparts. We performed an untargeted metabolomic analysis of serum from 30 ex-situ housed black rhinos (Eastern black rhino, EBR, n = 14 animals; Southern black rhino, SBR, n = 16 animals) and analyzed differences in metabolite profiles between subspecies, sex, and health status (healthy n = 13 vs. diseased n = 14). Of the 636 metabolites detected, several were differentially (fold change > 1.5; p < 0.05) expressed between EBR vs. SBR (40 metabolites), female vs. male (36 metabolites), and healthy vs. diseased (22 metabolites). Results suggest dysregulation of propanoate, amino acid metabolism, and bile acid biosynthesis in the subspecies and sex comparisons. Assessment of healthy versus diseased rhinos indicates involvement of arachidonic acid metabolism, bile acid biosynthesis, and the pentose phosphate pathway in animals exhibiting inflammatory disease syndromes. This study represents the first systematic characterization of the circulating serum metabolome in the black rhinoceros. Findings further implicate mitochondrial and immune dysfunction as key contributors for the diverse disease syndromes reported in ex-situ managed black rhinos.

Potentially Pathogenic Bacteria in Nesting Olive Ridley Turtles in Northwestern Mexico.

Olive ridleys (Lepidochelys olivacea) are the most common sea turtle found in the Gulf of California. Unfortunately, the bacterial flora of nesting olive ridley turtles is still unknown. We conducted a study to identify, characterize, serotype, and determine the antibiotic resistance of potentially pathogenic bacteria isolated from olive ridley turtles nesting in northwestern Mexico. Bacteria were isolated and identified from the oral cavity and cloaca of 47 postnesting turtles. Escherichia coli and Vibrio parahaemolyticus were characterized, and antibiotic resistance testing was performed. One hundred bacteria belonging to 21 species were isolated, 53 from the oral cavity and 47 from the cloaca, the most prevalent being Pseudomonas aeruginosa, followed by Aeromonas hydrophila, Vibrio alginolyticus, Vibrio parahaemolyticus, Klebsiella pneumoniae, and E. coli, among others. Moreover, two to three different bacterial species were found co-colonizing both anatomical sites in some turtles. E. coli phylogroups B1, A, F, and unknown were identified as diarrheagenic E. coli (enteroaggregative and enteropathogenic E. coli). O1, O4, K8, K12, OUT, and KUT of V. parahaemolyticus serogroups were identified, also comprising pathogenic and nonpathogenic strains. Finally, 100% of the bacterial species tested were antibiotic resistant, and both MDR and XDR strains were found. In conclusion, olive ridley turtles are colonized by a diversity of bacterial species with a high rate of antibiotic resistance, some with pathogenic potential to turtles, representing a health risk factor for the species.

Validation of an in vitro cytotoxicity test for four heavy metals using cell lines derived from a green sea turtle (Chelonia mydas).

Ten cell lines established from juvenile green sea turtles were tested and evaluated for their cytotoxic responses to four heavy metals: cadmium (Cd), chromium (Cr), zinc (Zn), and copper (Cu). Following a 24-h exposure to these metal salts at selected concentrations, test cells were comparatively characterized by morphology, viability, and proliferation. Experimental results indicated that all these metal salts were cytotoxic to these turtle cell lines at varied concentrations. Calculated 10% and 50% inhibitory concentration (IC(10) and IC(50)) values revealed that the cytotoxicities of Cd and Cr were significantly more potent than the other two metal salts (p < 0.01). Comparative analysis of IC(10) values in these ten cell lines showed that turtle lung cells (GT-LG) are the most sensitive cell line to Cd, Cr, Zn, and Cu. Among these turtle cell lines, turtle liver cells (GT-LV) are more tolerant than other cells to Cd, Cr, and Zn, while GT-EYE cells are more tolerant to Cu, as determined by IC(50) values. Overall, GT-LG represents the most sensitive cells to heavy metal contamination and may be used for initial environmental monitoring, while the highly tolerant nature of GT-LV and GT-EYE cells to the tested heavy metals suggest their potential use as an emergency last-resort indicator of potential metal-related adverse effect on human health.

Transdisciplinary and social-ecological health frameworks-Novel approaches to emerging parasitic and vector-borne diseases.

Ecosystem Health, Conservation Medicine, EcoHealth, One Health, Planetary Health and GeoHealth are inter-related disciplines that underpin a shared understanding of the functional prerequisites of health, sustainable vitality and wellbeing. All of these are based on recognition that health interconnects species across the planet, and they offer ways to more effectively tackle complex real-world challenges. Herein we present a bibliometric analysis to document usage of a subset of such terms by journals over time. We also provide examples of parasitic and vector-borne diseases, including malaria, toxoplasmosis, baylisascariasis, and Lyme disease. These and many other diseases have persisted, emerged or re-emerged, and caused great harm to human and animal populations in developed and low income, biodiverse nations around the world, largely because of societal drivers that undermined natural processes of disease prevention and control, which had developed through co-evolution over millennia. Shortcomings in addressing drivers has arisen from a lack or coordinated efforts among researchers, health stewards, societies at large, and governments. Fortunately, specialists collaborating under transdisciplinary and socio-ecological health umbrellas are increasingly integrating established and new techniques for disease modeling, prediction, diagnosis, treatment, control, and prevention. Such approaches often emphasize conservation of biodiversity for health protection, and they provide novel opportunities to increase the efficiency and probability of success.

Global Diversity and Distribution of Hantaviruses and Their Hosts.

Rodents represent 42% of the world's mammalian biodiversity encompassing 2,277 species populating every continent (except Antarctica) and are reservoir hosts for a wide diversity of disease agents. Thus, knowing the identity, diversity, host-pathogen relationships, and geographic distribution of rodent-borne zoonotic pathogens, is essential for predicting and mitigating zoonotic disease outbreaks. Hantaviruses are hosted by numerous rodent reservoirs. However, the diversity of rodents harboring hantaviruses is likely unknown because research is biased toward specific reservoir hosts and viruses. An up-to-date, systematic review covering all known rodent hosts is lacking. Herein, we document gaps in our knowledge of the diversity and distribution of rodent species that host hantaviruses. Of the currently recognized 681 cricetid, 730 murid, 61 nesomyid, and 278 sciurid species, we determined that 11.3, 2.1, 1.6, and 1.1%, respectively, have known associations with hantaviruses. The diversity of hantaviruses hosted by rodents and their distribution among host species supports a reassessment of the paradigm that each virus is associated with a single-host species. We examine these host-virus associations on a global taxonomic and geographical scale with emphasis on the rodent host diversity and distribution. Previous reviews have been centered on the viruses and not the mammalian hosts. Thus, we provide a perspective not previously addressed.

Nucleotide sequence of an ICP18.5 assembly protein (UL28) gene of green turtle herpesvirus pathogenically associated with green turtle fibropapilloma.

Because newly identified green turtle herpesvirus (GTHV) is associated pathogenically with marine turtle fibropapillomatosis (FP) and it has not been isolated in vitro, molecular sequencing and analysis of the genomic DNA of this putative reptilian herpesvirus will enhance the current understanding of GTHV in causing the FP disease. An inverse polymerase chain reaction (IPCR) genomic walking technique was developed to obtain new DNA sequences based on a portion of known genomic sequence. Through two genomic walks, a 2169 bp DNA fragment of GTHV was cloned and sequenced. Sequence analysis shows that this DNA fragment contains the entire gene of the UL28, as well as the partial genomic sequence of the UL27 gene. The UL28 gene is 2250 bp long and encodes a 750-amino acid peptide known as ICP18.5 assembly protein of herpesviruses. Phylogenetic analysis of the GHTV UL28 gene showed a high sequence homology with the UL28 homologs of other herpesviruses and supports the current classification of GTHV to be a member of Alphaherpesvirinae. Identification of the genomic sequences of GTHV provides a molecular base for the development of diagnostic immunoassay and also for the determination of the pathogenic role of GTHV infection.

Detection of polybrominated diphenyl ethers in tilapia (Oreochromis mossambicus) from O'ahu, Hawai;i.

Polybrominated diphenyl ethers (PBDEs) have been detected for the first time at a range from 231.58 to 685.61 ng g(-1) lipid weight in the muscles of tilapia (Oreochromis mossambicus) collected from O'ahu, an island of the geographically isolated Hawaiian archipelago.

Detection and quantitative analysis of polychlorinated biphenyls in tilapia from Hawaiian waters.

The purpose of this study was to investigate polychlorinated biphenyls (PCBs) contamination in tilapia (Oreochromis mossambicus) collected from the Manoa stream and Ala Wai Canal of O'ahu, an island of the geographically isolated Hawaiian archipelago. Our results show that the average concentrations of PCBs varied from 51.90 to 89.42 ng g(-1) lipid weight for the sampling sites. Relative toxic potencies (RTPs) and toxic equivalencies (TEQs) were determined to be 20.38-40.60 ng TCDDg(-1) lipid weight and 2.89-4.17 ng TEQ g(-1) lipid weight by 7-ethoxy-resorufin-O-deethylase (EROD) activity analysis and calculation of PCB concentrations based on toxic equivalency factors (TEFs), respectively. Penta-chlorinated congeners were found to be predominant, which revealed that Aroclor 1254 was a possible major source of PCBs in our fish samples. PCB 118, an indicator PCBs, constituted more than 55% and 30% of the total PCBs and TEQs, respectively. In addition, PCB 118 was found to have a linear correlation to the total PCBs (R=0.975) and TEQs (R=0.782). Detection of concentrated PCBs in Hawaiian waters suggests a potentially adverse impact of this pollutant on human health, as well as ecological systems, and suggests the necessity of environmental monitoring and hazard assessment of PCBs within the Hawaiian Islands.

Basic oxidative stress metabolites in eastern Pacific green turtles (Chelonia mydas agassizii).

Analysis of hematological and biochemical parameters, including oxidative stress indicators, is an invaluable tool in wildlife health assessment, particularly for threatened or endangered species. This study was aimed at obtaining baseline information of oxidative stress indicators in eastern Pacific green turtles (Chelonia mydas agassizii) from a relatively undisturbed habitat at Bahía Magdalena, Baja California Sur, Mexico. Tissues were analyzed for superoxide radical (O(2)(*-) production, lipid peroxidation (measured as thiobarbituric acid reactive substances, TBARS), and antioxidant enzyme activity (superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST)). Overall levels for all variables were within ranges reported for other reptile species. Results suggest differences in oxidative metabolism among tissues (p< or =0.05). Liver, lung and muscle had the highest levels of O(2)(*-) production. Liver revealed the highest TBARS levels. Liver and muscle showed the highest SOD activity, while liver and kidney had the highest CAT and GST activities. These data provide baseline values of the oxidative stress indicators in tissues from eastern Pacific green turtles. Development of a biomarker system to assess the health of wildlife species, especially one that could detect early exposure to environmental pollutants or emerging diseases, would provide a useful tool in the long-term conservation of the species.