Quantifying individual variability in exposure risk to mosquito bites in the Cascades region, Burkina Faso

Guglielmo, F., Sanou, A., Churcher, T., Ferguson, H. M. , Ranson, H. and Sherrard-Smith, E. (2021) Quantifying individual variability in exposure risk to mosquito bites in the Cascades region, Burkina Faso. Malaria Journal, 20, 44. (doi: 10.1186/s12936-020-03538-5) (PMID:33461560) (PMCID:PMC7814650)

[img] Text
229086.pdf - Published Version
Available under License Creative Commons Attribution.

1MB

Abstract

Background: The Cascades region, Burkina Faso, has a high malaria burden despite reported high insecticide-treated mosquito net (ITN) use. Human and vector activities outside the hours when indoor interventions offer direct protection from infectious bites potentially increase exposure risk to bites from malaria-transmitting Anopheles mosquitoes. This work investigated the degree of variation in human behaviour both between individuals and through time (season) to quantify how it impacts exposure to malaria vectors. Methods: Patterns in human overnight activity (18:00–06:00) to quantify time spent using an ITN across 7 successive nights in two rural communities, Niakore (N = 24 participants) and Toma (71 participants), were observed in the dry and rainy seasons, between 2017 and 2018. Hourly human landing Anopheles mosquito catches were conducted in Niakore specifically, and Cascades region generally, between 2016 and 2017. Data were statistically combined to estimate seasonal variation in time spent outdoors and Anopheles bites received per person per night (bpppn). Results: Substantial variability in exposure to outdoor Anopheles bites was detected within and between communities across seasons. In October, when Anopheles densities are highest, an individual’s risk of Anopheles bites ranged from 2.2 to 52.2 bites per person per night (bpppn) within the same week with variable risk dependent on hours spent indoors. Comparably higher outdoor human activity was observed in April and July but, due to lower Anopheles densities estimated, bpppn were 0.2–4.7 and 0.5–32.0, respectively. Males and people aged over 21 years were predicted to receive more bites in both sentinel villages. Conclusion: This work presents one of the first clear descriptions of the degree of heterogeneity in time spent outdoors between people and across the year. Appreciation of sociodemographic, cultural and entomological activities will help refine approaches to vector control.

Item Type:Articles
Additional Information:This work was supported by the Wellcome Trust under Grant Agreement Number [200222/Z/15/Z] MiRA through the “Improving the efficacy of malaria prevention in an insecticide resistant Africa (MiRA)”. ESS and TSC are supported by the Innovative Vector Control Consortium.
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:SANOU, ANTOINE and Ferguson, Professor Heather
Authors: Guglielmo, F., Sanou, A., Churcher, T., Ferguson, H. M., Ranson, H., and Sherrard-Smith, E.
College/School:College of Medical Veterinary and Life Sciences > Institute of Biodiversity Animal Health and Comparative Medicine
Journal Name:Malaria Journal
Publisher:BMC
ISSN:1475-2875
ISSN (Online):1475-2875

University Staff: Request a correction | Enlighten Editors: Update this record