| Sumario: |
Background: Anthropogenic land use may influence transmission of multi-host vector-borne pathogens by changing
diversity, relative abundance, and community composition of reservoir hosts. These reservoir hosts may have varying
competence for vector-borne pathogens depending on species-specific characteristics, such as life history strategy. The
objective of this study is to evaluate how anthropogenic land use change influences blood meal species composition and
the effects of changing blood meal species composition on the parasite infection rate of the Chagas disease vector Rhodnius
pallescens in Panama.
Methodology/Principal Findings: R. pallescens vectors (N = 643) were collected in different habitat types across a gradient
of anthropogenic disturbance. Blood meal species in DNA extracted from these vectors was identified in 243 (40.3%) vectors
by amplification and sequencing of a vertebrate-specific fragment of the 12SrRNA gene, and T. cruzi vector infection was
determined by pcr. Vector infection rate was significantly greater in deforested habitats as compared to contiguous forests.
Forty-two different species of blood meal were identified in R. pallescens, and species composition of blood meals varied
across habitat types. Mammals (88.3%) dominated R. pallescens blood meals. Xenarthrans (sloths and tamanduas) were the
most frequently identified species in blood meals across all habitat types. A regression tree analysis indicated that blood
meal species diversity, host life history strategy (measured as rmax, the maximum intrinsic rate of population increase), and
habitat type (forest fragments and peridomiciliary sites) were important determinants of vector infection with T. cruzi. The
mean intrinsic rate of increase and the skewness and variability of rmax were positively associated with higher vector
infection rate at a site.
Conclusions/Significance: In this study, anthropogenic landscape disturbance increased vector infection with T. cruzi,
potentially by changing host community structure to favor hosts that are short-lived with high reproductive rates. Study
results apply to potential environmental management strategies for Chagas disease.
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