Paracoccidioidomycosis ceti in an Atlantic bottlenose dolphin (Tursiops truncatus), Brazil

Health conditions of Guiana dolphins facing cumulative anthropogenic impacts

Coastal areas are associated with anthropogenic activities and stressors that can expose the marine fauna to negative cumulative impacts. Apex predators, such as dolphins, can flag the quality of their environment through health parameters such as cutaneous and body conditions. We examined the potential relationship between environmental conditions and health parameters of Guiana dolphins around a port and a conservation unit within the Paranaguá Estuarine Complex, southern Brazil. During boat surveys between July 2018 and April 2019 covering both areas, we measured environmental parameters, photographed dolphins to infer their health condition and the frequency of use of the estuary. In total, 204 individual Guiana dolphins were photo-identified, 52 of which were seen in both years. In general, dolphins showed poor body condition (76% classified as emaciated or thin in 2018, and 79% in 2019), diverse cutaneous conditions (four types of lesions suggestive of an infectious aetiology, two conditions suggestive of traumatic events of anthropogenic origin, and two anomalous pigmentation) and a high prevalence of such cutaneous conditions (85% in 2018, 70% in 2019). Most individuals maintained their body and cutaneous conditions between the two years. There were no clear differences between the port and the conservation areas in terms of environmental conditions, frequency of use and health conditions of individual dolphins, suggesting that dolphins inhabiting this estuarine complex are exposed to potential cumulative impacts, such as pollutants, noise and habitat degradation. This study provides baseline information on some health parameters of Guiana dolphins in southern Brazil and highlights the need for systematic, long-term health assessment of Guiana dolphin populations to guide conservation actions to safeguard this vulnerable species.

The taxonomy of two uncultivated fungal mammalian pathogens is revealed through phylogeny and population genetic analyses

Ever since the uncultivated South American fungal pathogen Lacazia loboi was first described 90 years ago, its etiology and evolutionary traits have been at the center of endless controversies. This pathogen infects the skin of humans and as long believed, dolphin skin. However, recent DNA analyses of infected dolphins placed its DNA sequences within Paracoccidioides species. This came as a surprise and suggested the human and dolphin pathogens may be different species. In this study, population genetic analyses of DNA from four infected dolphins grouped this pathogen in a monophyletic cluster sister to P. americana and to the other Paracoccidioides species. Based on the results we have emended the taxonomy of the dolphin pathogen as Paracoccidioides cetii and P. loboi the one infecting human. Our data warn that phylogenetic analysis of available taxa without the inclusion of unusual members may provide incomplete information for the accurate classification of anomalous species.

Case report of respiratory aspergillosis and candidiasis in wild Magellanic penguins (Spheniscus magellanicus), Brazil

Magellanic penguins (Spheniscus magellanicus) migrate to the continental shelf of southern-southeastern Brazil during austral winter. Stranded penguins are directed to rehabilitation centers, where they occasionally develop fungal diseases. Aspergillosis, a mycosis caused by Aspergillus spp., is one of the most important diseases of captive penguins, while Candida sp. has been detected in penguins undergoing rehabilitation. Nevertheless, their occurrence in the wild is poorly understood. This study surveyed the occurrence of mycoses in free-ranging Magellanic penguins wintering in southeastern Brazil. These penguins were either found dead or stranded alive and died during transport to a rehabilitation center. Overall, 61 fresh to moderate autolyzed carcasses were necropsied. Upon necropsy, three juvenile males (4.9%) presented mycotic-consistent gross lesions. Histopathology and panfungal PCRs confirmed the mycoses. Major microscopic findings were marked chronic necrotizing multifocal to coalescent pneumonia, airsacculitis, and esophageal/gastric serositis with two types of intralesional fungal structures: (a) septated acute-angled branching hyphae (n = 2) and (b) yeast structures (n = 1), both PAS- and Grocott-positive. Sequences identical to Aspergillus sp. were retrieved in two cases, while the third had sequences identical to Candida palmioleophila. This study describes two cases of aspergillosis and one of candidiasis in free-ranging Magellanic penguins, confirming the species' susceptibility in the wild. These mycoses could be associated with the animals' poor body condition, and/or impaired immunity, and natural and anthropogenic challenges related to migration. To the authors' knowledge, this is the first report of aspergillosis in free-ranging Magellanic penguins in the Atlantic Ocean and of candidiasis in penguins worldwide.

Pulmonary adiaspiromycosis in armadillos killed by motor vehicle collisions in Brazil

Knowledge of infectious diseases in wildlife provides important information for preventing potential outbreaks of zoonotic diseases. Adiaspiromycosis is a neglected human disease caused by dimorphic Onygenales fungi. The disease is produced by the inflammatory response against growing adiaspores, leading to granulomatous pneumonia. In humans, adiaspiromycosis is relevant in immunosuppressed patients. In animals, it is associated with pneumonia in fossorial species. Given the potential role of armadillos in the epidemiology of adiaspiromycosis, in this study, we sought to investigate the occurrence and pathological features of adiaspiromycosis in roadkilled armadillos. In total, 54 armadillo carcasses were suitable for postmortem pathologic examinations between February 2017 and 2020. Adiaspores, associated with granulomatous lesions, were observed in ten six-banded (Euphractus sexcinctus) and two southern naked-tailed armadillos (Cabassous unicinctus). A previously uncharacterized Onygenales species was molecularly identified in two E. sexcinctus. In summary, herein we report 12 cases of pulmonary adiaspiromycosis (PA) in two species of free-living armadillos in Brazil. Both, the morphology of the fungus, as well as the histopathological findings (granulomatous inflammatory response to adiaspores) are consistent with PA; however, as the molecular identification differs from the reported species, the potential impact of this fungus for human PA is unknown, and we cannot rule out its impact on public health.

Seroprevalence of Antibodies Against Paracoccidioides Spp. in Captive Dolphins from Three Aquaria in Japan

The skin disease paracoccidioidomycosis ceti occurs in several dolphin species globally. Infection by the unculturable fungi Paracoccidioides brasilensis or other Paracoccidioides spp. results in chronic cutaneous and granulomatous lesions. In this study we used immunohistochemistry to investigate the seroprevalence of antibodies to Paracoccidioides spp. in captive dolphins from three aquaria in Japan. We had previously reported that there were serological cross-reactions for Paracoccidioides spp. with related species in the order Onygenales. We hypothesized that the degree of serological cross-reactions for Paracoccidioides spp. might be lower in areas, such as Japan, where the fungal diseases coccidiodomycosis and paracoccidiodomycosis are not endemic. Sera from 41 apparently healthy dolphins, including 20 Atlantic bottlenose dolphins (BD: Tursiops truncatus), 6 Indo-Pacific bottlenose dolphins (IPBD: Tursiops aduncus), 2 F1 generation of a cross between BD and IPBD (F1), 3 Pacific white-sided dolphins (PWD: Lagenorhynchus obliquidens), 2 pantropical spotted dolphins (PSD: Stenella attenuata), 6 false killer whales (FKW: Pseudorca crassidens), and 2 rough-toothed dolphins (RTD: Steno bredanensis) were investigated. Sera from three dolphins with paracoccidioidomycosis ceti were used as a positive control. The yeast-form cells of Paracoccidioides spp. in the cutaneous tissue sample derived from the first Japanese paracoccidioidomycosis ceti case were used as the antigen for the immunohistochemistry. Of the 41 dolphins tested, 61.0% had antibodies against Paracoccidioides spp. This indicates that dolphins of several species in Japanese aquaria have likely been exposed to the pathogen Paracoccidioides spp.