Author:
Garcia-Longoria Luz,Magallanes Sergio,Huang Xi,Drews Anna,Råberg Lars,Marzal Alfonso,Bensch Staffan,Westerdahl Helena
Abstract
Abstract
Background
Hosts are often simultaneously infected with several parasite species. These co-infections can lead to within-host interactions of parasites, including mutualism and competition, which may affect both virulence and transmission. Birds are frequently co-infected with different haemosporidian parasites, but very little is known about if and how these parasites interact in natural host populations and what consequences there are for the infected hosts. We therefore set out to study Plasmodium and Haemoproteus parasites in house sparrows Passer domesticus with naturally acquired infections using a protocol where the parasitemia (infection intensity) is quantified by qPCR separately for the two parasites. We analysed infection status (presence/absence of the parasite) and parasitemia of parasites in the blood of both adult and juvenile house sparrows repeatedly over the season.
Results
Haemoproteus passeris and Plasmodium relictum were the two dominating parasite species, found in 99% of the analyzed Sanger sequences. All birds were infected with both Plasmodium and Haemoproteus parasites during the study period. Seasonality explained infection status for both parasites in the adults: H. passeris was completely absent in the winter while P. relictum was present all year round. Among adults infected with H. passeris there was a positive effect of P. relictum parasitemia on H. passeris parasitemia and likewise among adults infected with P. relictum there was a positive effect of H. passeris parasitemia on P. relictum parasitemia. No such associations on parasitemia were seen in juvenile house sparrows.
Conclusions
The reciprocal positive relationships in parasitemia between P. relictum and H. passeris in adult house sparrows suggests either mutualistic interactions between these frequently occurring parasites or that there is variation in immune responses among house sparrow individuals, hence some individuals suppress the parasitemia of both parasites whereas other individuals suppress neither. Our detailed screening of haemosporidian parasites over the season shows that co-infections are very frequent in both juvenile and adult house sparrows, and since co-infections often have stronger negative effects on host fitness than the single infection, it is imperative to use screening systems with the ability to detect multiple parasites in ecological studies of host-parasite interactions.
Funder
Junta de Extremadura
Consejería de Economía, Innovación, Ciencia y Empleo, Junta de Andalucía
H2020 European Research Council
Lund University
Publisher
Springer Science and Business Media LLC
Reference46 articles.
1. Cattadori IM, Boag B, Hudson PJ. Parasite co-infection and interaction as drivers of host heterogeneity. Int J Parasitol. 2008;38:371–80.
2. Schmid-Hempel P. Evolutionary parasitology: the integrated study of infections, immunology, ecology, and genetics. Oxford: Oxford University Press; 2011.
3. Alizon S, Van Baalen M. Multiple infections, immune dynamics, and the evolution of virulence. Am Nat. 2008;172:150–68.
4. Martin M, Blackwell AD, Gurven M, Kaplan H. Make new friends and keep the old? Parasite coinfection and comorbidity in Homo sapiens. In: Brinkworth JF, Pechenkina K, editors. Primates, pathogens, and evolution. New York, NY: Springer New York; 2013. p. 363–87.
5. Marzal A, Bensch S, Reviriego M, Balbontin J, De Lope F. Effects of malaria double infection in birds: one plus one is not two. J Evol Biol. 2008;21:979–87.
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