Interplay between insecticide-treated bed-nets and mosquito demography: implications for malaria control

Autor: Jemal Mohammed-Awel, Olivia Prosper, Calistus N. Ngonghala, Ruijun Zhao
Rok vydání: 2016
Předmět:
0301 basic medicine
Insecticides
Mosquito Control
Time Factors
Disease
Mosquito demography and reproduction patterns
Mathematical model for malaria
0302 clinical medicine
Medicine(all)
Agricultural and Biological Sciences(all)
Applied Mathematics
General Medicine
Mosquito control
Treatment Outcome
Modeling and Simulation
Backward bifurcation
Sensitivity analysis
General Agricultural and Biological Sciences
Malaria control
Algorithms
Statistics and Probability
Plasmodium falciparum
030231 tropical medicine
Biology
Models
Biological
General Biochemistry
Genetics and Molecular Biology
Host-Parasite Interactions
03 medical and health sciences
Modelling and Simulation
Immunology and Microbiology(all)
parasitic diseases
medicine
Animals
Humans
Insecticide-Treated Bednets
Bed nets
Life Cycle Stages
General Immunology and Microbiology
Biochemistry
Genetics and Molecular Biology(all)
medicine.disease
biology.organism_classification
Insect Vectors
Malaria
Culicidae
030104 developmental biology
Disease risk
Biased feeding preference
Basic reproduction number
Demography
Zdroj: Journal of Theoretical Biology. 397:179-192
ISSN: 0022-5193
DOI: 10.1016/j.jtbi.2016.03.003
Popis: Although malaria prevalence has witnessed a significant reduction within the past decade, malaria still constitutes a major health and economic problem, especially to low-income countries. Insecticide-treated nets (ITNs) remain one of the primary measures for preventing the malignant disease. Unfortunately, the success of ITN campaigns is hampered by improper use and natural decay in ITN-efficacy over time. Many models aimed at studying malaria transmission and control fail to account for this decay, as well as mosquito demography and feeding preferences exhibited by mosquitoes towards humans. Omitting these factors can misrepresent disease risk, while understanding their effects on malaria dynamics can inform control policy. We present a model for malaria dynamics that incorporates these factors, and a systematic analysis, including stability and sensitivity analyses of the model under different conditions. The model with constant ITN-efficacy exhibits a backward bifurcation emphasizing the need for sustained control measures until the basic reproduction number, R0, drops below a critical value at which control is feasible. The infectious and partially immune human populations and R0 are highly sensitive to the probability that a mosquito feeds successfully on a human, ITN coverage and the maximum biting rate of mosquitoes, irrespective of whether ITN-efficacy is constant or declines over time. This implies that ITNs play an important role in disease control. When ITN-efficacy wanes over time, we identify disease risks and corresponding ITN coverage, as well as feeding preference levels for which the disease can be controlled or eradicated. Our study leads to important insights that could assist in the design and implementation of better malaria control strategies. We conclude that ITNs that can retain their effectiveness for longer periods will be more appropriate in the fight against malaria and that making more ITNs available to highly endemic regions is necessary for malaria containment.
Databáze: OpenAIRE
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