Galapagos giant tortoises are the largest terrestrial vertebrates and one of the most iconic species of the Galapagos islands. Their populations continue to be endangered because of multiple factors, mostly driven by anthropogenic activities. In recent years, the presence of novel infectious agents of potential conservation concern, including two adenoviruses and two herpesviruses, has been reported in some Galapagos tortoise species. With the aim of describing the presence and prevalence of these pathogens in additional tortoise species, we collected oral, ocular, and cloacal swabs from 99 free-living tortoises from San Cristobal (Chelonoidis chathamensis) and Isabela islands (Chelonoidis vicina and Chelonoidis guntheri) and screened these for the presence of herpesvirus and adenovirus by PCR. We detected Chelonoidis adenovirus 1 (CheAdV1) and Chelonoidis adenovirus 2 (CheAdV2) in all sampling locations, whereas we did not detect herpesvirus in any tortoises. Phylogenetic analyses revealed that San Cristobal nucleotide and amino acid sequences clustered in a clade with CheAdV1, whereas the Isabela nucleotide and amino acid sequences clustered together with CheAdV2. This contributes additional information regarding tortoise viral distribution in the Galapagos Archipelago. We recommend long-term health surveillance of tortoises and other wildlife species to inform conservation actions in the Galapagos involving captive-breeding and rewilding programs.
Background/Objectives: Increasing levels of antimicrobial resistance (AMR) have recently been observed at the human–domestic animal–wildlife interface. Wild birds have been identified as carriers of antimicrobial-resistant bacteria and serve as excellent biomarkers for epidemiological studies. This study assessed the current AMR presence in Eastern Spain’s commensal Escherichia coli isolated from free-ranging Bonelli’s eagles (Aquila fasciata). Methods: Nestlings and their nests were intensively sampled between 2022 and 2024 to determine their AMR profile and characterize E. coli. AMR testing was conducted using the broth microdilution method, following the European Committee on Antimicrobial Susceptibility Testing guidelines. Additionally, the presence of eaeA (intimin gene) and stx-1 and stx-2 (shiga toxins) was analyzed by real-time PCR to classify E. coli strains into enteropathogenic (EPEC) and Shiga-toxigenic (STEC) pathotypes. Results: Of all E. coli isolates, 41.7% were resistant to at least one antimicrobial, and 30% were multidrug-resistant. Only two strains were classified as EPEC and none as STEC. The highest resistance rates were observed for amoxicillin and tetracycline (19.6% each). Alarmingly, resistance to colistin and meropenem, last-resort antibiotics in human medicine, was also detected. Conclusions: Although the mechanisms of resistance acquisition remain unclear, transmission is likely to occur through the food chain, with synanthropic prey acting as intermediary vectors. These results highlight the role of Bonelli’s eagles as essential sentinels of environmental AMR dissemination, even in remote ecosystems. Strengthening One Health-based surveillance is necessary to address AMR’s ecological and public health risks in wildlife.
Bats (order Chiroptera) are known as important hosts and reservoirs for several zoonotic viruses. To this date, most virology studies in bats have focused on RNA viruses; consequently, information about DNA viruses is more limited. Herein we surveyed the presence of herpesviruses in blood or spleen samples of three bat species of Spain (n = 31) and five bat species of Chile (n = 50) by using a broad-spectrum nested PCR. Overall, herpesvirus DNA was detected in 9.7% (3/31) bats of Spain and 10.0% (5/50) bats of Chile. Three gammaherpesvirus sequence types were found in bats from Spain, while sequence types of two betaherpesviruses, two gammaherpesviruses and one unclassified herpesvirus were detected in Chilean bats, two of which could represent novel herpesvirus species. The impact (if any) of these herpesviruses on the health of the studied species needs to be clarified. This study increases our knowledge of herpesvirus diversity in bats and expands their geographic range in South America. Future herpesvirus surveillance studies are warranted to test chiropteran families other than Vespertilionidae and Molossidae in Chile and Spain.
Anthropogenic environments are critical hotspots for the emergence and persistence of antimicrobial resistance (AMR). Extensive livestock pastures and landfills are of particular concern due to their high bacterial diversity and frequent wildlife visitation, facilitating the transfer of antimicrobial resistance genes (ARGs). The white stork (Ciconia ciconia) heavily exploits landfills and extensive pastures in Spain, providing an ideal model to study AMR emergence. We evaluated the diversity and burden of ARGs in breeding white storks across three stages of the breeding season, reflecting different foraging strategies. Fecal samples from 31 nests were collected during two breeding seasons (2020-2021) and screened for 21 ARGs across eight antibiotic classes using real-time qPCR. ARGs were universally present, and over 70 % of nests contained fecal samples harboring genes conferring resistance to three or more antibiotic classes, indicating a high burden of potential multi-drug resistance at the community level. Generalized linear models identified breeder age and sampling period as strong predictors of total ARG burden (p < 0.001), with older breeders contributing more ARG burden early in the season, although this effect diminished later. Landfill use showed only a weak association with ARG burden, while nest success approached significance. These findings suggest that foraging dynamics, rather than landfill exposure alone, strongly influence ARG acquisition in white storks. Agricultural pastures and other anthropogenic environments may play a larger role in shaping resistomes than previously assumed. Understanding how wildlife foraging behavior drives AMR carriage is crucial to better characterize AMR transmission risk at the wildlife-livestock interface.
We report the detection of hemotropic mycoplasmas in 4 immunosuppressed pediatric patients in Spain: 2 solid organ transplant recipients, 1 hematopoietic stem cell transplant recipient, and 1 cancer patient. Sequences were 100% identical to a strain previously identified in Miniopterus schreibersii bats, which raises concerns about unnoticed zoonotic transmission.
Wildlife health assessments including haematology and biochemistry parameters are essential to evaluating the well-being of free-living species. In Galapagos, the iconic giant tortoises still thrive in the archipelago despite anthropogenic pressures, with up to 13 extant species distributed across most islands and ecosystems. In previous work conducted by our research group, we described for the first-time reference intervals of haematology and plasma biochemistry in four Galapagos tortoise species. With the aim of continuing to provide cutting-edge health data for Galapagos tortoises, here we report haematology and plasma biochemistry descriptive statistics, reference intervals and cell morphology of tortoises from four different tortoise populations (i.e. Alcedo Volcano, Cerro Azul Volcano, Cinco Cerros and Sierra Negra Volcano). Additionally, we compared values between sexes and applied a principal component analysis to explore differences in haematology and biochemistry parameters between tortoise populations, including those previously published by our research group. Females presented higher calcium, phosphorus and albumin, consistent with vitellogenesis, whereas males had higher packed cell volume and sodium than females. Blood cell morphology was consistent across species. The two main principal components of the multivariate statistical model were unable to explain >44.9% of the variance across tortoise populations. We suggest additional research to explore the correlation between anthropogenic factors (i.e. climate change, pesticides, plastics) and blood values, for a deeper understanding of tortoise physiology and ultimately improved diagnostics and management actions. In the anthropogenic era, understanding the health status of bioindicator species like Galapagos tortoises is mandatory to inform current and future conservation priorities and actions.
Hemotropic mycoplasmas (hemoplasmas) are emerging zoonotic pathogens. Micromammals have received little attention as hosts for hemoplasmas despite their ubiquitous presence, high population abundances, and close association with humans. A PCR protocol targeting a fragment of the 16 S rRNA gene and direct sequencing in blood samples of 189 adult specimens and 35 fetuses belonging to three species of Eulipotyphla (shrews) and seven species of Rodentia, captured in three ecologically diverse habitats in North-Eastern Spain (Steppe, High Mountain, Mediterranean) yielded and occurrence of 26%, including 36% of 39 shrews and 23% of 150 rodents. Sequencing revealed the presence of 14 nucleotide sequence types (ntST) among the 56 readable sequences. In general, each ntST was associated with a given host species, although in some cases, the same ntST was sequenced in different species (chiefly rodents). Most ntST were closely related to rodent and/or bat hemoplasmas, but one was identical with Mycoplasma haemocanis/haemofelis, and others can be considered novel genotypes. High sequence diversity was detected in rodents, whereas in the white-toothed shrew (Crocidura russula), 9/11 sequences from two distant areas were identical. Phylogenetic and network analyses classified our sequences in different clades including hemoplasmas of rodents, carnivores, bats, and humans. Twelve of the fetuses (34.2%) of 9/12 litters (75.0%) of shrews and rodents were hemoplasma-positive, indicating frequent vertical transmission. Our study contributes to expanding our knowledge about the distribution, diversity, and transmission of hemoplasmas.
IntroductionAlthough pets provide several social–emotional benefits for children, the risk of zoonosis must be considered among immunocompromised individuals.MethodsA prospective study was conducted in a tertiary hospital including immunocompromised patients younger than 20 years owning dogs and/or cats. Colonization and/or infection was evaluated by stool studies, bacterial swabs, blood polymerase chain reaction and serological studies in both patients and their pets, to evaluate potential zoonotic transmission occurrence.ResultsWe included 74 patients and their 92 pets (63 dogs, 29 cats). Up to 44.6% of the patients and 31.5% of the pets had at least 1 positive result. Up to 18.4% of pets’ fecal samples were positive (bacteria, parasites or hepatitis E virus). No helminths were observed despite the high frequency of incorrect intestinal deworming practices. Among children, gastrointestinal microorganisms were found in 37.3% (primarily Clostridium difficile). Colonization by Staphylococcus pseudintermedius was common among pets (8.0%) but not among children (0.0%). No shared colonization between owners and pets was observed, except in one case (Blastocystis in both patient and pet feces). Among patients, serologies were positive for Strongyloides stercoralis (14.8%), Toxocara canis (3.2%), Bartonella henselae (19.1%) and hepatitis E (5.6%). Serology was positive for Rickettsia spp. (22.6%) and Babesia spp. (6.5%) in dogs and for Leishmania spp. (14.3%) and Toxoplasma spp. (14.3%) in cats.ConclusionExposure to zoonotic agents was detected in both patients and pets; however, shared colonization events were almost nonexistent. In our cohort, dogs and cats do not appear to entail high zoonosis transmission risk for immunocompromised patients.
Antimicrobial Resistance (AMR) poses a global threat to both human health and environmental well-being. Our study delved into Costa Rican wildlife reserves, uncovering a substantial human impact on these ecosystems and underscoring the imperative to pinpoint AMR hotspots. Embracing a One Health perspective, we advocated for a comprehensive landscape analysis that intricately intertwined geographic, climatic, forest, and human factors. This study illuminated the link between laboratory results and observed patterns of antimicrobial use, thereby paving the way for sustainable solutions. Our innovative methodology involved deploying open-ended questions to explore antimicrobial usage across livestock activities, contributing to establishing a comprehensive methodology. Non-invasive sampling in wildlife emerged as a critical aspect, shedding light on areas contaminated by AMR. Feline species, positioned at the apex of the food chain, acted as sentinels for environmental health due to heightened exposure to improperly disposed waste. Regarding laboratory findings, each sample revealed the presence of at least one antimicrobial resistance gene (ARG). Notably, genes encoding resistance to tetracyclines dominated (94.9%), followed by beta-lactams (75.6%), sulfonamides (53.8%), aminoglycosides (51.3%), quinolones (44.9%), phenicols (25.6%), and macrolides (20.5%). Genes encoding polymyxins were not detected. Moreover, 66% of samples carried a multi-resistant microbiome, with 15% exhibiting resistance to three antimicrobial families and 51% to four. The absence of a correlation between forest coverage and ARG presence underscored the profound human impact on wildlife reserves, surpassing previous estimations. This environmental pressure could potentially modify microbiomes and resistomes in unknown ways. As not all antimicrobial families encoding ARGs were utilized by farmers, our next step involved evaluating other human activities to identify the primary sources of contamination. This comprehensive study contributed crucial insights into the intricate dynamics of AMR in natural ecosystems, paving the way for targeted interventions and sustainable coexistence.
Urbanization is often associated with homogenization, including the homogenization of biodiversity and overpopulation by generalist species that can change community and disease dynamics. In Madrid, nestlings of Eurasian Scops Owl Otus scops frequently suffer necrotic oropharyngeal disease as a result of infection by Gongylonema sp., a parasitic nematode transmitted by adult owls to their offspring through the diet, more specifically through consumption of a pest species: the oriental cockroach Blatta orientalis. We studied how the presence of cockroaches and owl infection rates are affected by urban features such as green areas. We found that a higher number of birds were affected by the parasite in the initial period of the breeding season and in areas with greater surface area of green spaces. We suggest that urban management should promote the diversity of insects in green areas so that the owls diversify their dietary offer to their offspring, to reduce the prevalence of the disease and improve their breeding success in the city of Madrid, as this problem has not yet been described in other cities.
Normal reference intervals (RI) of hematologic and biochemical parameters are important for assessing and monitoring the health status of captive and free-living chelonians; however, such information is not available for most wildlife species. Giant Galapagos tortoises are one of the most iconic animals on earth and health information can make an important contribution to their conservation and management. This study provides formal RI of haematology and plasma biochemistry parameters and describes cell morphology along with morphometrics of free-living Eastern Santa Cruz (Chelonoidis donfaustoi), Española (Chelonoidis hoodensis) and San Cristóbal tortoises (Chelonoidis chathamensis). We explored differences in blood parameters between sexes, across the tortoise species in this study and with previously published RI of the Western Santa Cruz tortoise (Chelonoidis porteri). Biochemistry parameters of both Santa Cruz species were overall more similar to each other than to Española and San Cristobal tortoises. This research constitutes the first RI for these three Galapagos tortoise species and may be of value for advising captive-breeding and conservation plans. We recommend further research to establish RI in additional tortoise species so we may better understand and interpret haematology and biochemistry parameters as a valuable conservation tool for species of this critically endangered taxon.
Hepatic and pulmonary lesions are common in cetaceans, despite their poorly understood viral etiology. Herpesviruses (HV), adenoviruses (AdV) and hepatitis E virus (HEV) are emerging agents in cetaceans, associated with liver and/or pulmonary damage in mammals. We isolated and molecularly tested DNA for HV and AdV (n = 218 individuals; 187 liver and 108 lung samples) and RNA for HEV (n = 147 animals; 147 liver samples) from six cetacean families. All animals stranded or were bycaught in Brazil between 2001 and 2021. Positive-animals were analyzed by histopathology. Statistical analyses assessed if the prevalence of viral infection could be associated with the variables: species, family, habitat, region, sex, and age group. All samples were negative for AdV and HEV. Overall, 8.7% (19/218) of the cetaceans were HV-positive (4.8% [9/187] liver and 11.1% [12/108] lung), without HV-associated lesions. HV-prevalence was statistically significant higher in Pontoporiidae (19.2%, 10/52) when compared to Delphinidae (4.1%, 5/121), and in southeastern (17.1%, 13/76)—the most industrialized Brazilian region—when compared to the northeastern region (2.4%, 3/126). This study broadens the herpesvirus host range in cetaceans, including its description in pygmy sperm whales (Kogia breviceps) and humpback whales (Megaptera novaeangliae). Further studies must elucidate herpesvirus drivers in cetaceans.
Passeriformes populations have experienced a marked decline in number during the last decades. Several infectious agents have been described as key factors for this population’s decrease, as they can cause mortal diseases like the recently reported Suttonella ornithocola . S. ornithocola is a bacterium from the Cardiobacteriaceae family that has been linked to several outbreaks. This systematic review aims to collect all the scientific information available about S. ornithocola to better understand its epidemiology and pathogenesis and to assess the potential hazard that it can pose to garden songbirds. Although it has been considered a respiratory pathogen, S. ornithocola has been isolated from several organs, suggesting a systemic pathogenesis. However, it has also been described as a normal taxon from the microbiota of some bird species. Therefore, further studies in healthy birds are necessary to establish if S. ornithocola is a primary pathogen or an opportunistic bacterium in songbirds.
A significant gap in exposure data for most livestock and zoonotic pathogens is common for several Latin America deer species. This study examined the seroprevalence against 13 pathogens in 164 wild and captive southern pudu from Chile between 2011 and 2023. Livestock and zoonotic pathogen antibodies were detected in 22 of 109 wild pudus (20.18%; 95% CI: 13.34–29.18) and 17 of 55 captive pudus (30.91%; 95% CI: 19.52–44.96), including five Leptospira interrogans serovars (15.38% and 10.71%), Toxoplasma gondii (8.57% and 37.50%), Chlamydia abortus (3.03% and 12.82%), Neospora caninum (0.00% and 9.52%), and Pestivirus (8.00% and 6.67%). Risk factors were detected for Leptospira spp., showing that fawn pudu have statistically significantly higher risk of positivity than adults. In the case of T. gondii, pudu living in “free-range” have a lower risk of being positive for this parasite. In under-human-care pudu, a Pestivirus outbreak is the most strongly suspected as the cause of abortions in a zoo in the past. This study presents the first evidence of Chlamydia abortus in wildlife in South America and exposure to T. gondii, L. interrogans, and N. caninum in wild ungulate species in Chile. High seroprevalence of livestock pathogens such as Pestivirus and Leptospira Hardjo in wild animals suggests a livestock transmission in Chilean template forest.
Virus surveillance in wildlife is important to understanding ecosystem health, taxonomy, and evolution. Nevertheless, viruses in reptiles, and specifically in squamates, continue to be understudied. Herein, we conducted a health assessment on the critically endangered Galapagos pink land iguana (Conolophus marthae) and the vulnerable Galapagos land iguana (Conolophus subcristatus). We collected oral and/or cloacal swabs from 47 clinically healthy iguanas and tested for adenovirus (cloacal swabs, n = 47) and herpesvirus (oral swabs, n = 45) using broad-spectrum PCRs. Two out of 38 (5.3 %) Galapagos pink land iguanas tested positive for herpesvirus, while no herpesvirus was detected in all Galapagos land iguanas (n = 7). Both herpesviral sequences were identical between them and divergent (61.9 % amino acid identity) when compared to the closest herpesvirus sequences available in GenBank/EMBL/DDBJ. The genetic distance between this and other herpesviruses is consistent with its classification as a novel virus species. All iguanas were negative for adenovirus. This is the first description of a herpesvirus in iguanas of the Galapagos islands, and the first report of a potential pathogen for the iconic Galapagos pink land iguana. Further research is needed to understand the implications of this virus in the conservation and management of one of the most endangered iguana species in the world.
Pathogens affect wild bird populations worldwide, contributing to their decline. Considering the scarce health data regarding the endangered Pyrenean Capercaillie (Tetrao urogallus aquitanicus), we molecularly surveyed selected pathogens (Newcastle disease virus, Avian influenza virus, Chlamydia psittaci, avian pathogenic Escherichia coli, Campylobacter jejuni, and Salmonella spp.) in 30 Pyrenean Capercaillie feces collected in the field (Catalonia, northeastern Spain). Additionally, swab and tissue samples from eight wild Pyrenean Capercaillies of Catalonia and Andorra were molecularly tested for herpesvirus and hemosporidians (Plasmodium spp., Haemoproteus spp., and Leucocytozoon spp.). All fecal samples were negative for the pathogens tested. Nevertheless, we detected a novel herpesvirus in 50% (4/8) of the Pyrenean Capercaillies, and hemosporidian DNA in 62.5% (5/8) of the tissue samples (i.e., Haemoproteus sp. [4 of 8] and/or Leucocytozoon sp. [3 of 8]). To our knowledge, this is the first detection of herpesvirus and hemosporidians infections in Pyrenean Capercaillies. The putative novel herpesvirus belongs to the genus Iltovirus. The presence of hemosporidian parasites in this mountain bird species is of concern, and could be related to the marked increase in the average temperature in the Pyrenees as a consequence of climate change. Our findings are fundamental to improve the conservation plans for the endangered Pyrenean Capercaillie population.
Viral diseases jeopardize the health of wildlife in Chile. However, this country lacks health surveillance programs that allow for defining preventive measures to tackle such diseases. The objective of this study was to determine the occurrence and the genetic diversity of pestivirus, herpesvirus and adenovirus in pudus from Chile. Blood samples from wild (n=34) and captive (n=32) pudus were collected between 2011 and 2019 and analyzed through consensus PCR. All the samples were negative to pestivirus and adenovirus. Herpesvirus was confirmed in four captive, and one wild pudu. All four zoo animals share the same sequence for both polymerase and glycoprotein genes. Both sequences share a 100% identity with caprine herpesvirus-2, classifying them in the same cluster as the Macavirus group. In turn, novel sequences of the polymerase and glycoprotein B genes were obtained from the wild pudu. Our study reports the first evidence of CpHV-2 infection in Chile and South American ungulate populations. Further research will be necessary to assess the pathogenicity of CpHV-2 in this species. It is also urgently recommended that molecular, serological and pathological screening should be conducted in Chilean wild and captive pudus to understand the impact of the herpesvirus on their populations.