'A flying start': Wildlife trypanosomes in tissues of Australian tabanids (Diptera: Tabanidae).
Infect Genet Evol
; 96: 105152, 2021 12.
Article
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| MEDLINE
| ID: mdl-34823027
ABSTRACT
Tabanids (syn. horse flies) are biting-flies of medical and veterinary significance because of their ability to transmit a range of pathogens including trypanosomes - some species of which carry a combined health and biosecurity risk. Invertebrate vectors responsible for transmitting species of Trypanosoma between Australian wildlife remains unknown, thus establishing the role of potential vector candidates such as tabanids is of utmost importance. The current study aimed to investigate the presence of indigenous trypanosomes in tabanids from an endemic area of south-west Australia. A total of 148 tabanids were collected, with morphological analysis revealing two subgenera Scaptia (Pseudoscione) and S. (Scaptia) among collected flies. A parasitological survey using an HRM-qPCR and sequencing approach revealed a high (105/148; 71%) prevalence of trypanosomatid DNA within collected tabanids. Individual tissues - proboscis (labrum, labium and mandibles, hypopharynx), salivary glands, proventriculus, midgut, and hindgut and rectum - were also tested from a subset of 20 tabanids (n = 140 tissues), confirming the presence of Trypanosoma noyesi in 31% of screened tissues, accompanied by T. copemani (3%) and T. vegrandis/T.gilletti (5%). An unconfirmed trypanosomatid sp. was also detected (9%) within tissues. The difference between tissues infected with T. noyesi compared with tissues infected with other trypanosome species was statistically significant (p < 0.05), revealing T. noyesi as the more frequent species detected in the tabanids examined. Fluorescence in situ hybridisation (FISH) and scanning electron microscopy (SEM) confirmed intact parasites within salivary glands and the proboscis respectively, suggesting that both biological and mechanical modes of transmission could occur. This study reveals the presence of Australian Trypanosoma across tabanid tissues and confirms intact parasites within tabanid salivary glands and the proboscis for the first time. Further investigations are required to determine whether tabanids have the vectorial competence to transmit Australian trypanosomes between wildlife.
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Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
Trypanosoma
/
Tripanosomiasis
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Dípteros
/
Insectos Vectores
Tipo de estudio:
Risk_factors_studies
País/Región como asunto:
Oceania
Idioma:
En
Revista:
Infect Genet Evol
Asunto de la revista:
BIOLOGIA
/
DOENCAS TRANSMISSIVEIS
/
GENETICA
Año:
2021
Tipo del documento:
Article