Interacting effects of wildlife loss and climate on ticks and tick-borne disease.
Proc Biol Sci
; 284(1862)2017 Sep 13.
Article
em En
| MEDLINE
| ID: mdl-28878055
ABSTRACT
Both large-wildlife loss and climatic changes can independently influence the prevalence and distribution of zoonotic disease. Given growing evidence that wildlife loss often has stronger community-level effects in low-productivity areas, we hypothesized that these perturbations would have interactive effects on disease risk. We experimentally tested this hypothesis by measuring tick abundance and the prevalence of tick-borne pathogens (Coxiella burnetii and Rickettsia spp.) within long-term, size-selective, large-herbivore exclosures replicated across a precipitation gradient in East Africa. Total wildlife exclusion increased total tick abundance by 130% (mesic sites) to 225% (dry, low-productivity sites), demonstrating a significant interaction of defaunation and aridity on tick abundance. When differing degrees of exclusion were tested for a subset of months, total tick abundance increased from 170% (only mega-herbivores excluded) to 360% (all large wildlife excluded). Wildlife exclusion differentially affected the abundance of the three dominant tick species, and this effect varied strongly over time, likely due to differences among species in their host associations, seasonality, and other ecological characteristics. Pathogen prevalence did not differ across wildlife exclusion treatments, rainfall levels, or tick species, suggesting that exposure risk will respond to defaunation and climate change in proportion to total tick abundance. These findings demonstrate interacting effects of defaunation and aridity that increase disease risk, and they highlight the need to incorporate ecological context when predicting effects of wildlife loss on zoonotic disease dynamics.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Carrapatos
/
Mudança Climática
/
Doenças Transmitidas por Carrapatos
/
Animais Selvagens
Tipo de estudo:
Prognostic_studies
/
Risk_factors_studies
Limite:
Animals
País como assunto:
Africa
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article