LSTM Home > LSTM Research > LSTM Online Archive

Modelling the impact of insecticide-based control interventions on the evolution of insecticide resistance and disease transmission

Barbosa, Susana, Kay, Katherine, Chitnis, Nakul and Hastings, Ian ORCID: https://orcid.org/0000-0002-1332-742X (2018) 'Modelling the impact of insecticide-based control interventions on the evolution of insecticide resistance and disease transmission'. Parasites & Vectors, Vol 11, Issue 1.

[img]
Preview
Text
s13071-018-3025.pdf - Published Version
Available under License Creative Commons Attribution.

Download (1MB) | Preview

Abstract

Background
Current strategies to control mosquito-transmitted infections use insecticides targeted at various stages of the mosquito life-cycle. Control is increasingly compromised by the evolution of insecticide resistance but there is little quantitative understanding of its impact on control effectiveness. We developed a computational approach that incorporates the stage-structured mosquito life-cycle and allows tracking of insecticide resistant genotypes. This approach makes it possible to simultaneously investigate: (i) the population dynamics of mosquitoes throughout their whole life-cycle; (ii) the impact of common vector control interventions on disease transmission; (iii) how these interventions drive the spread of insecticide resistance; and (iv) the impact of resistance once it has arisen and, in particular, whether it is sufficient for malaria transmission to resume. The model consists of a system of difference equations that tracks the immature (eggs, larvae and pupae) and adult stages, for males and females separately, and incorporates density-dependent regulation of mosquito larvae in breeding sites.

Results
We determined a threshold level of mosquitoes below which transmission of malaria is interrupted. It is based on a classic Ross-Macdonald derivation of the malaria basic reproductive number (R0) and may be used to assess the effectiveness of different control strategies in terms of whether they are likely to interrupt disease transmission. We simulated different scenarios of insecticide deployment by changing key parameters in the model to explore the comparative impact of insecticide treated nets, indoor residual spraying and larvicides.

Conclusions
Our simulated results suggest that relatively low degrees of resistance (in terms of reduced mortality following insecticide contact) can induce failure of interventions, and the rate of spread of resistance is faster when insecticides target the larval stages. The optimal disease control strategy depends on vector species demography and local environmental conditions but, in our illustrative parametrisation, targeting larval stages achieved the greatest reduction of the adult population, followed by targeting of non-host-seeking females, as provided by indoor residual spraying. Our approach is designed to be flexible and easily generalizable to many scenarios using different calibrations and to diseases other than malaria.

Item Type: Article
Subjects: QX Parasitology > Insects. Other Parasites > QX 510 Mosquitoes
QX Parasitology > Insects. Other Parasites > QX 600 Insect control. Tick control
QX Parasitology > Insects. Other Parasites > QX 650 Insect vectors
WA Public Health > Preventive Medicine > WA 110 Prevention and control of communicable diseases. Transmission of infectious diseases
Faculty: Department: Biological Sciences > Department of Tropical Disease Biology
Digital Object Identifer (DOI): https://doi.org/10.1186/s13071-018-3025-z
SWORD Depositor: JISC Pubrouter
Depositing User: Stacy Murtagh
Date Deposited: 12 Sep 2018 15:53
Last Modified: 12 Sep 2018 15:53
URI: https://archive.lstmed.ac.uk/id/eprint/9265

Statistics

View details

Actions (login required)

Edit Item Edit Item