Publications by authors named "Marcela Uhart"

Article Synopsis
  • H5N1 high pathogenicity avian influenza has caused significant deaths among marine mammals in South America, particularly highlighted by an outbreak affecting southern elephant seals in Argentina in October 2023.
  • Comprehensive genomic analysis reveals a distinct clade of H5N1 viruses found in both seals and terns, showing similarities with viruses from other South American countries.
  • Findings indicate a potential for mammal-to-mammal transmission of H5N1, raising concerns about its adaptability to mammals and possible impacts on wildlife, human health, and livestock globally.
View Article and Find Full Text PDF

Ocean pollution by plastics is a growing concern for marine wildlife conservation, and seabirds are particularly prone to ingest plastics. We report baseline information on plastic ingestion in 17 procellariiform species along the coast of Brazil and Argentina. Through a collaborative regional effort we found plastic items in 30.

View Article and Find Full Text PDF

The resurgence of H5N1 avian influenza highlights the urgent need for robust surveillance systems to detect zoonotic risks before they evolve into human-to-human transmission. The One Health approach-integrating human, animal, and environmental health-offers a comprehensive framework for addressing these challenges. H5N1, a highly pathogenic avian influenza virus, has caused significant mortality in avian populations and poses a serious threat to human health.

View Article and Find Full Text PDF

Brucellosis is a worldwide zoonotic disease caused by Brucella spp. and transmitted from domestic and wild animals to humans. Brucellosis causes important economic losses in livestock, has a significant impact on public health, and may affect the health of wildlife.

View Article and Find Full Text PDF

Anthropogenic pollution poses a threat to marine conservation by causing chronic toxic effects. Seabirds have contact throughout their lives with pollutants like plastic, metals, polychlorinated biphenyls (PCBs), and organochlorine pesticides such as hexachlorocyclohexanes (HCHs). We assessed 155 Manx shearwaters (Puffinus puffinus) stranded along the Brazilian coast, analyzing associations between organic pollutants, plastic ingestion, biomarkers (transcript levels of aryl hydrocarbon receptor, cytochrome P450-1A-5 [CYP1A5], UDP-glucuronosyl-transferase [UGT1], estrogen receptor alpha-1 [ESR1], and heat shock protein-70 genes) and enzymes activity (ethoxy-resorufin O-deethylase and glutathione S-transferase [GST]).

View Article and Find Full Text PDF

Wildlife trafficking creates favorable scenarios for intra- and inter-specific interactions that can lead to parasite spread and disease emergence. Among the fauna affected by this activity, primates are relevant due to their potential to acquire and share zoonoses - infections caused by parasites that can spread between humans and other animals. Though it is known that most primate parasites can affect multiple hosts and that many are zoonotic, comparative studies across different contexts for animal-human interactions are scarce.

View Article and Find Full Text PDF

Trichinellosis is a foodborne disease caused by ingestion of raw or undercooked meat containing Trichinella spp. larvae. Consumption of wild boar (Sus scrofa) meat represents an important source of human trichinellosis worldwide.

View Article and Find Full Text PDF

The hepatitis E virus (HEV) is an emergent zoonotic virus causing viral hepatitis worldwide. Clinically, hepatitis E is not easily distinguished from other types of acute viral hepatitis. There is a need for HEV diagnostic assays to detect and prevent interspecies transmission among susceptible populations.

View Article and Find Full Text PDF

Fibropapillomatosis (FP) is a disease characterized by epithelial tumors that can impede life-sustaining activities of sea turtles, especially green turtles (Chelonia mydas). FP is caused by a herpesvirus, but environmental factors are also thought to play a role in triggering FP tumor growth. In this study, we evaluate the epidemiology of FP tumors in green turtles along the coast of Espírito Santo, Brazil, a region where juvenile green turtles are known to aggregate with high FP prevalence.

View Article and Find Full Text PDF

Plastic ingestion is a problem for seabirds worldwide. In addition to direct health effects such as obstruction or perforation of the gastrointestinal tract, plastic ingestion can also lead to indirect health effects through the release of chemicals that may be absorbed and cause systemic and chronic toxicity. Among chemicals that can be released by plastics are phthalate esters, a group of chemicals widely used as plasticizers or additives to change the physical characteristics of plastics.

View Article and Find Full Text PDF

Hydatid disease is a neglected zoonotic parasitic disease caused by cysts of the tapeworm Echinococcus granulosus. Canids, especially domestic dogs, are definitive hosts of the parasite and are the most pragmatic targets for control programs. A governmental dog deworming campaign was established in 1979 to control hydatidosis in southern Chile, which succeeded in reducing the prevalence of canine echinococcosis in Tierra del Fuego province from 68.

View Article and Find Full Text PDF
Article Synopsis
  • Scientists study how viruses and their animal hosts have changed together over time and how they can jump from animals to humans.
  • They used special models to see which newly found viruses from wildlife might be able to infect people, focusing on high-risk areas in Africa, Asia, and Latin America.
  • The research shows that new coronaviruses might infect more types of animals compared to other viruses, helping to figure out where to look for potential outbreaks in humans.
View Article and Find Full Text PDF
Article Synopsis
  • - The research focuses on the energetic costs of gestation in southern right whales, detailing how fetal growth rates and birth size correlate with the mother's body size.
  • - By analyzing historical whaling data and using photogrammetry, the study quantifies the costs associated with fetal maintenance and growth throughout different trimesters of pregnancy.
  • - Findings reveal that while fetal growth is rapid, the majority of gestation costs occur in the last trimester, with the heat of gestation accounting for the highest energy expenditure.
View Article and Find Full Text PDF

Sarcoptic mange epidemics can devastate wildlife populations. In 2014, mange was first detected in vicuñas (Vicugna vicugna) and guanacos (Lama guanicoe) in San Guillermo National Park (SGNP), Argentina. This study describes the temporal dynamics of the outbreak, its effects on the park's wild camelid populations between 2017-2019, and investigates the potential source of the epidemic.

View Article and Find Full Text PDF
Article Synopsis
  • In Península Valdés, Argentina, southern right whales (SRWs) are exposed to domoic acid (DA), a toxic substance from certain algae that can cause serious health issues and even death.
  • Researchers validated a method to measure stress hormones in SRW feces and found that whales with detectable levels of DA had significantly lower stress hormone levels than those without.
  • Despite the small sample size, the study suggests that DA exposure could lead to changes in adrenal function in these whales, highlighting potential impacts of environmental toxins on marine mammal health.
View Article and Find Full Text PDF

Although the ingestion of plastics and other anthropogenic debris by seabirds is a global problem, few studies have employed standardized protocols to quantify and classify the debris ingested by seabirds in the Southwest Atlantic. We evaluated the ingestion of marine debris (items >0.1 mm) by 126 coastal and pelagic birds (19 species) along the coast of Espírito Santo, Eastern Brazil.

View Article and Find Full Text PDF

Obtaining endocrine data from alternative sample types such as baleen and other keratinized tissues has proven a valuable tool to investigate reproductive and stress physiology via steroid hormone quantification, and metabolic stress via thyroid hormone quantification in whales and other vertebrates. These alternative sample types provide an integrated measure of plasma levels over the period that the structure was growing, thus capturing months or even years of an individual's endocrine history. Additionally, their robust and stable keratin matrix allows such samples to be stored for years to decades, enabling the analysis and comparison of endocrine patterns from past and modern populations.

View Article and Find Full Text PDF

Objective: To describe and quantify the extent of wildlife and environment sector inclusion in country evaluation and prioritization tools for health security, and to provide practical recommendations for global and national action to improve pandemic prevention and preparedness.

Methods: To assess coverage of wildlife and other environmental aspects, we reviewed major health security reports (including World Organisation for Animal Health Performance of Veterinary Services reports, and World Health Organization Joint External Evaluations and follow-on National Action Plans for Health Security) published by 107 countries and territories. We extracted information on stated coverage gaps, wildlife surveillance systems and priority diseases.

View Article and Find Full Text PDF

This is the first field study to evaluate lead exposure in dogs fed game meat and offal and, to our knowledge, the first study exploring associations between game consumption and dog health status. We quantified lead concentrations in blood and hair and haematological parameters of 31 dogs fed game meat and offal from wild boar (Sus scrofa) and axis deer (Axis axis) culled with lead ammunition in El Palmar National Park, Argentina. Despite variable weekly frequency in game consumption, dogs had detectable blood and hair lead levels, demonstrating recent and chronic exposure.

View Article and Find Full Text PDF

Consumption of meat from animals hunted with Pb ammunition can cause toxic accumulation with consequent health risks, even if relatively small amounts are consumed in each exposure. In El Palmar National Park, Argentina, invasive alien mammals, wild boar (Sus scrofa) and axis deer (Axis axis), are culled with Pb ammunition and their meat is consumed. In this study, we evaluated blood Pb concentrations in 58 consumers of culled game and examined Pb exposure risk according to their demographics, duty, and consumption habits.

View Article and Find Full Text PDF

Over one hundred cases of human rickettsiosis, many fatal, are reported annually across the US-Mexico transboundary region, representing a likely undercount. Although cases are often attributed to Rickettsia rickettsii, the agent of Rocky Mountain spotted fever, multiple other Rickettsia pathogens are present in North America. We conducted multiple-host surveillance of domestic, synanthropic, and sylvatic mammals and their ectoparasites to investigate the ecology of Rickettsia species in this region.

View Article and Find Full Text PDF

Background: In 2007-2009, a major yellow fever virus (YFV) outbreak in Northern Argentina decimated the local howler monkey (Alouatta) population.

Aims: To evaluate whether the surviving howler monkeys possess advantageous genetic variants inherited from monkeys alive prior to the YFV outbreak, we explored the relationship between Toll-like receptor (TLR) 7 and TLR8 gene variation and YFV susceptibility.

Methods: We used samples from Alouatta individuals in Misiones, Argentina alive before the YFV outbreak, individuals that died during the outbreak, and individuals that survived the outbreak and are alive today.

View Article and Find Full Text PDF