Linking predator–prey interactions with exposure to a trophically transmitted parasite usingPCR‐based analyses

Abstract

Parasite transmission is determined by the rate of contact between a susceptible host and an infective stage and susceptibility to infection given an exposure event. Attempts to measure levels of variation in exposure in natural populations can be especially challenging. The level of exposure to a major class of parasites, trophically transmitted parasites, can be estimated by investigating the host's feeding behaviour. Since the parasites rely on the ingestion of infective intermediate hosts for transmission, the potential for exposure to infection is inherently linked to the definitive host's feeding ecology. Here, we combined epidemiological data and molecular analyses (polymerase chain reaction) of the diet of the definitive host, the white-footed mouse (Peromyscus leucopus), to investigate temporal and individual heterogeneities in exposure to infection. Our results show that the consumption of cricket intermediate hosts accounted for much of the variation in infection; mice that had consumed crickets were four times more likely to become infected than animals that tested negative for cricket DNA. In particular, pregnant female hosts were three times more likely to consume crickets, which corresponded to a threefold increase in infection compared with nonpregnant females. Interestingly, males in breeding condition had a higher rate of infection even though breeding males were just as likely to test positive for cricket consumption as nonbreeding males. These results suggest that while heterogeneity in host diet served as a strong predictor of exposure risk, differential susceptibility to infection may also play a key role, particularly among male hosts. By combining PCR analyses with epidemiological data, we revealed temporal variation in exposure through prey consumption and identified potentially important individual heterogeneities in parasite transmission.

MOLECULAR ASSESSMENT OFHEPATOZOON(APICOMPLEXA: ADELEORINA) INFECTIONS IN WILD CANIDS AND RODENTS FROM NORTH AFRICA, WITH IMPLICATIONS FOR TRANSMISSION DYNAMICS ACROSS TAXONOMIC GROUPS

“…Thus, the implications of these modes of transmission may be of importance in disease ecology and evolution and need to be further studied. Luong et al (2013) have shown the usefulness of combining epidemiologic data and molecular analyses of the diet of the host to link predator-prey interactions with exposure to trophically transmitted parasites. Similar approaches could be used in future research regarding the systems analyzed in our study.…”

Distribution extension of Syphacia (Seuratoxyuris) peromysci Harkema, 1936 (Nematoda, Syphaciinae) parasitizing the Rock Mouse, Peromyscus difficilis (J. A. Allen, 1891) (Rodentia, Neotominae) in central Mexico

“…Since then, this taxon has been recorded in several species of Peromyscus (P. gossypinus, P. leucopus, P. maniculatus, and P. polionotus;Dyer 1969;Grundman et al 1976;Kinsella 1991;Luong et al 2013;Quentin and Kinsella 1972) also in USA. In Mexico this species has been recorded in P. maniculatus in Hidalgo (Pulido-Flores et al 2005).…”

Network transmission inference: Host behavior and parasite life cycle make social networks meaningful in disease ecology

“…Parasite-mediated changes in host behavior are a fascinating addition to this because the parasite manipulates the host phenotype and can lead to a potential nonlinear increase in transmission (Moore 2002, Poulin 2010. But how host behavior, outside of parasite-induced phenomena, relates to transmission dynamics needs further attention and is difficult to study (Altizer et al 2003, Kjaer et al 2008, Luong et al 2013. Empirically estimating and evaluating the importance of exposure heterogeneity, in a manner that is meaningful when the transmission of parasites is considered, is an emerging challenge.…”