Impact of asynchronous emergence of two lethal pathogens on amphibian assemblages.
Sci Rep
; 7: 43260, 2017 02 27.
Article
en En
| MEDLINE
| ID: mdl-28240267
ABSTRACT
Emerging diseases have been increasingly associated with population declines, with co-infections exhibiting many types of interactions. The chytrid fungus (Batrachochytrium dendrobatidis) and ranaviruses have extraordinarily broad host ranges, however co-infection dynamics have been largely overlooked. We investigated the pattern of co-occurrence of these two pathogens in an amphibian assemblage in Serra da Estrela (Portugal). The detection of chytridiomycosis in Portugal was linked to population declines of midwife-toads (Alytes obstetricans). The asynchronous and subsequent emergence of a second pathogen - ranavirus - caused episodes of lethal ranavirosis. Chytrid effects were limited to high altitudes and a single host, while ranavirus was highly pathogenic across multiple hosts, life-stages and altitudinal range. This new strain (Portuguese newt and toad ranavirus - member of the CMTV clade) caused annual mass die-offs, similar in host range and rapidity of declines to other locations in Iberia affected by CMTV-like ranaviruses. However, ranavirus was not always associated with disease, mortality and declines, contrasting with previous reports on Iberian CMTV-like ranavirosis. We found little evidence that pre-existing chytrid emergence was associated with ranavirus and the emergence of ranavirosis. Despite the lack of cumulative or amplified effects, ranavirus drove declines of host assemblages and changed host community composition and structure, posing a grave threat to all amphibian populations.
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
Quitridiomicetos
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Ranavirus
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Infecciones por Virus ADN
/
Estadios del Ciclo de Vida
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Micosis
Tipo de estudio:
Prevalence_studies
/
Risk_factors_studies
País/Región como asunto:
Europa
Idioma:
En
Revista:
Sci Rep
Año:
2017
Tipo del documento:
Article