Quantifying Heterogeneity in Host-Vector Contact: Tsetse Glossina swynnertoni and G. pallidipes Host Choice in Serengeti National Park, TanzaniaReport as inadecuate




Quantifying Heterogeneity in Host-Vector Contact: Tsetse Glossina swynnertoni and G. pallidipes Host Choice in Serengeti National Park, Tanzania - Download this document for free, or read online. Document in PDF available to download.

Background

Identifying hosts of blood-feeding insect vectors is crucial in understanding their role in disease transmission. Rhodesian human African trypanosomiasis rHAT, also known as acute sleeping sickness is caused by Trypanosoma brucei rhodesiense and transmitted by tsetse flies. The disease is commonly associated with wilderness areas of east and southern Africa. Such areas hold a diverse range of species which form communities of hosts for disease maintenance. The relative importance of different wildlife hosts remains unclear. This study quantified tsetse feeding preferences in a wilderness area of great host species richness, Serengeti National Park, Tanzania, assessing tsetse feeding and host density contemporaneously.

Methods

Glossina swynnertoni and G. pallidipes were collected from six study sites. Bloodmeal sources were identified through matching Cytochrome B sequences amplified from bloodmeals from recently fed flies to published sequences. Densities of large mammal species in each site were quantified, and feeding indices calculated to assess the relative selection or avoidance of each host species by tsetse.

Results

The host species most commonly identified in G. swynnertoni bloodmeals, warthog 94-220, buffalo 48-220 and giraffe 46-220, were found at relatively low densities 3-11-km2 and fed on up to 15 times more frequently than expected by their relative density. Wildebeest, zebra, impala and Thomson’s gazelle, found at the highest densities, were never identified in bloodmeals. Commonly identified hosts for G. pallidipes were buffalo 26-46, giraffe 9-46 and elephant 5-46.

Conclusions

This study is the first to quantify tsetse host range by molecular analysis of tsetse diet with simultaneous assessment of host density in a wilderness area. Although G. swynnertoni and G. pallidipes can feed on a range of species, they are highly selective. Many host species are rarely fed on, despite being present in areas where tsetse are abundant. These feeding patterns, along with the ability of key host species to maintain and transmit T. b. rhodesiense, drive the epidemiology of rHAT in wilderness areas.



Author: Harriet Auty , Sarah Cleaveland, Imna Malele, Joseph Masoy, Tiziana Lembo, Paul Bessell, Stephen Torr, Kim Picozzi, Susan C. Welb

Source: http://plos.srce.hr/



DOWNLOAD PDF




Related documents