Autor: |
Elliot SL; Department of Entomology, Universidade Federal de Viçosa, Campus Universitário, Viçosa, Minas Gerais, Brazil., Rodrigues Jde O; Centro de Pesquisa René Rachou, Belo Horizonte, Minas Gerais, Brazil., Lorenzo MG; Centro de Pesquisa René Rachou, Belo Horizonte, Minas Gerais, Brazil., Martins-Filho OA; Centro de Pesquisa René Rachou, Belo Horizonte, Minas Gerais, Brazil., Guarneri AA; Centro de Pesquisa René Rachou, Belo Horizonte, Minas Gerais, Brazil. |
Jazyk: |
angličtina |
Zdroj: |
PLoS neglected tropical diseases [PLoS Negl Trop Dis] 2015 Mar 20; Vol. 9 (3), pp. e0003646. Date of Electronic Publication: 2015 Mar 20 (Print Publication: 2015). |
DOI: |
10.1371/journal.pntd.0003646 |
Abstrakt: |
It is often assumed that parasites are not virulent to their vectors. Nevertheless, parasites commonly exploit their vectors (nutritionally for example) so these can be considered a form of host. Trypanosoma cruzi, a protozoan found in mammals and triatomine bugs in the Americas, is the etiological agent of Chagas disease that affects man and domestic animals. While it has long been considered avirulent to its vectors, a few reports have indicated that it can affect triatomine fecundity. We tested whether infection imposed a temperature-dependent cost on triatomine fitness. We held infected insects at four temperatures between 21 and 30°C and measured T. cruzi growth in vitro at the same temperatures in parallel. Trypanosoma cruzi infection caused a considerable delay in the time the insects took to moult (against a background effect of temperature accelerating moult irrespective of infection status). Trypanosoma cruzi also reduced the insects' survival, but only at the intermediate temperatures of 24 and 27°C (against a background of increased mortality with increasing temperatures). Meanwhile, in vitro growth of T. cruzi increased with temperature. Our results demonstrate virulence of a protozoan agent of human disease to its insect vector under these conditions. It is of particular note that parasite-induced mortality was greatest over the range of temperatures normally preferred by these insects, probably implying adaptation of the parasite to perform well at these temperatures. Therefore we propose that triggering this delay in moulting is adaptive for the parasites, as it will delay the next bloodmeal taken by the bug, thus allowing the parasites time to develop and reach the insect rectum in order to make transmission to a new vertebrate host possible. |
Databáze: |
MEDLINE |
Externí odkaz: |
|
Nepřihlášeným uživatelům se plný text nezobrazuje |
K zobrazení výsledku je třeba se přihlásit.
|