Mosquito electrocuting traps for directly measuring biting rates and host-preferences of Anopheles arabiensis and Anopheles funestus outdoors.

Authors:
Katharina S Kreppel
Katharina S Kreppel
Institute of Infection and Global Health
Deodatus F Maliti
Deodatus F Maliti
Ifakara Health Institute
Amos T Mlwale
Amos T Mlwale
Ifakara Health Institute
Nosrat Mirzai
Nosrat Mirzai
University of Glasgow
Gerry F Killeen
Gerry F Killeen
Ifakara Health Institute
Tanzania
Heather M Ferguson
Heather M Ferguson
Institute of Biodiversity
United Kingdom
Nicodem J Govella
Nicodem J Govella
Ifakara Health Institute
United Kingdom

Malar J 2019 Mar 18;18(1):83. Epub 2019 Mar 18.

Environmental Health and Ecological Sciences Department, Ifakara Health Institute, Off Mlabani Passage, P.O. Box 53, Ifakara, Tanzania.

Background: Mosquito biting rates and host preferences are crucial determinants of human exposure to vector-borne diseases and the impact of vector control measures. The human landing catch (HLC) is a gold standard method for measuring human exposure to bites, but presents risks to participants by requiring some exposure to mosquito vectors. Mosquito electrocuting traps (METs) represent an exposure-free alternative to HLCs for measuring human exposure to malaria vectors. However, original MET prototypes were too small for measuring whole-body biting rates on humans or large animals like cattle. Here a much larger MET capable of encompassing humans or cattle was designed, and its performance was evaluated relative to both the original small MET and HLC and for quantifying malaria vector host preferences.

Methods: Human landing catch, small human-baited METs (MET-SH), and large METs baited with either a human (MET-LH) or calves (MET-LC) were simultaneously used to capture wild malaria vectors outdoors in rural southern Tanzania. The four capture methods were compared in a Latin-square design over 20 nights. Malaria vector host preferences were estimated through comparison of the number of mosquitoes caught by large METs baited with either humans or cattle.

Results: The MET-LH caught more than twice as many Anopheles arabiensis than either the MET-SH or HLC. It also caught higher number of Anopheles funestus sensu lato (s.l.) compared to the MET-SH or HLC. Similar numbers of An. funestus sensu stricto (s.s.) were caught in MET-LH and MET-SH collections. Catches of An. arabiensis with human or cattle-baited large METs were similar, indicating no clear preference for either host. In contrast, An. funestus s.s. exhibited a strong, but incomplete preference for humans.

Conclusions: METs are a sensitive, practical tool for assessing mosquito biting rates and host preferences, and represent a safer alternative to the HLC. Additionally these findings suggest the HLC underestimate whole-body human exposure. MET collections indicated the An. funestus s.s. population in this setting had a higher than expected attack rate on cattle, potentially making eliminating of this species more difficult with human-targetted control measures. Supplementary vector control tools targetted at livestock may be required to effectively tackle this species.

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Source
http://dx.doi.org/10.1186/s12936-019-2726-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6423841PMC
March 2019

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References

(Supplied by CrossRef)
Article in Trends Parasitol.
IN Lyimo et al.
Trends Parasitol. 2009
Article in Malar J.
GF Killeen et al.
Malar J. 2014
Article in BMJ Glob Health.
GF Killeen et al.
BMJ Glob Health. 2017
Article in Malar J.
GF Killeen et al.
Malar J. 2014
Article in Am J Trop Med Hyg
G Killeen et al.
Am J Trop Med Hyg 2006
Article in PLoS Negl Trop Dis.
NL Achee et al.
PLoS Negl Trop Dis. 2015
Article in Parasit Vectors.
A Seyoum et al.
Parasit Vectors. 2012
Article in Mem Inst Oswaldo Cruz
JBP Lima et al.
Mem Inst Oswaldo Cruz 2014
Article in Tanzan J Health Res.
LEG Mboera et al.
Tanzan J Health Res. 2005
Article in Experientia
R Jong De et al.
Experientia 1995
Article in Entomol Exp Appl
T Dekker et al.
Entomol Exp Appl 1998

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