Urban forests as hubs for novel zoonosis: blood meal analysis, seasonal variation inCulicoides(Diptera: Ceratopogonidae) vectors, and avian haemosporidians

Abstract

Culicoides vectors can transmit a diverse array of parasites and are globally distributed. We studied feeding preferences and seasonal variation of Culicoides (Diptera: Ceratopogonidae) vectors in an urban forest of Germany to determine whether humans living nearby are readily exposed to vector-borne parasites from wild animals. We used a fragment of the mtDNA COI gene to identify hosts from blood meals. We amplified a fragment of the mtDNA cyt b to detect haemosporidian infections in Culicoides abdomens and thoraxes. We detected a total of 22 Culicoides species. Fifty-eight blood meals (84%) were from humans, 10 from birds, and one from livestock. We found Culicoides kibunensis (considered ornithophilic) with 29 human blood meals. Host generalist Culicoides festivipennis and Culicoides obsoletus had 14 human blood meals. Culicoides clastrieri and Culicoides semimaculatus fed on birds; previously humans were their only known host. Six thoraxes and three abdomens were infected with either Haemoproteus pallidulus or Haemoproteus parabelopolskyi. There were changes in Culicoides community structure across months. Culicoides pictipennis was the dominant species during spring, C. kibunensis and C. clastrieri were dominant during summer, and C. obsoletus was dominant by early autumn. All dominant species were generalists feeding on birds, livestock and humans. Our results indicate that humans can serve as a blood source for dominant Culicoides species instead of the normal wild animal hosts in urban areas.

Different meal, same flavor: cospeciation and host switching of haemosporidian parasites in some non-passerine birds

“…Moreover, phylogenetically related haemosporidian lineages (e.g., sister lineages) do not necessarily have a similar host breadth and geographic distribution [74], which challenges our ability to predict novel haemosporidian zoonoses. Taken together, the evidence on host distributions suggests that haemosporidian parasites have the potential to rapidly develop novel host-associations [19], but see [64]. …”

“…Previous work suggests that different dipteran families are specialized in transmitting different Haemosporida genera [e.g., Ceratopogonidae transmit only Haemoproteus ( Parahaemoproteus ) parasites, [22,47]. Recent work on Culicidae [57-59] and Ceratopogonidae [18,19,60,61] shows that many vector species have broad feeding preferences, even across vertebrate classes. Thus, vectors may come in contact with a diverse array of Haemosporida parasites, including genera they do not normally transmit [e.g., [18,60,62-64].…”

Dynamics of prevalence and diversity of avian malaria infections in wild Culex pipiens mosquitoes: the effects of Wolbachia, filarial nematodes and insecticide resistance

“…All lineages identified here are known to infect both migratory and sedentary Passeriforms (Table 1 ), except DELURB5, which has, to date, only been sampled from a migratory bird, the common house martin ( Delichon urbicum ), in Spain [ 66 ]. Interestingly, the highest richness in terms of the number of lineages happens in the summer, coinciding with both the period of high vector abundance, a common pattern in haemosporidia [ 97 ], and with the breeding period of migratory birds in the study area.…”

Searching for putative avian malaria vectors in a Seasonally Dry Tropical Forest in Brazil

“…Assessing host-feeding patterns of blood-feeding dipterans can reveal vectors of zoonotic pathogens [50]. Our blood meal analysis revealed that all tested mosquito species feed upon humans, and Ma.…”