Thesis (MComm)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Tsetse flies (Glossina spp), native to mid-continental Africa, are the vectors
of trypanosomes that causes human (sleeping sickness) and animal (nagana)
trypanosomiasis. Vector control plays a major role in alleviating the burden
of the disease. Mathematical models of tsetse population dynamics provide
insights into how best to manage these control efforts.
A major mark-recapture experiment, carried out in Zimbabwe, provided
valuable information on tsetse population dynamics, but the analyses so far
published could be improved on because not all of the information available
on the marking procedure was used.
We have constructed an individual-based model that follows the life of individual
tsetse flies, their progeny and, in particular, the sequence of occasions
on which individual flies were captured and given distinctive marks. We have
access to comprehensive data from the tsetse fly mark-release-recapture experiment
carried out on Antelope Island, Lake Kariba, Zimbabwe. In order
to calibrate or validate the model, we model both the growth of the introduced
tsetse population and the mark-recapture process. We have compared
the model outputs to the original data and recommend processes that may be
followed for model calibration.
It is possible to construct an individual-based model that adequately models
tsetse fly populations. Whereas the focus of this study has been on modelling
the mark-recapture study, the individual-based model could also be used
in more general settings to model the growth, and reduction in fly numbers,
changes in age structure, species and gender ratios and the acquisition of trypanosome
infections by individual flies. This model can thus be used to investigate the effect of various factors on tsetse fly and trypanosome, population
dynamics as well as on the performance of various control techniques effecting
fly mortality and disease transmission. / AFRIKAANSE OPSOMMING: Tsetsevlieë (Glossina spp), inheems aan sentraalkontinentale Afrika, is die draers
van trypanosomen wat trypanosomiasis by die mens (slaapsiekte) en by
diere (nagana) veroorsaak. Die beheer van draers speel 'n belangrike rol om
die las wat die siekte veroorsaak, te verlig. Wiskundige modelle van tsetse bevolkingsdinamika
bied insigte oor hoe om beheerpogings die beste te bestuur.
'n Belangrike merk-hervang eksperiment, wat in Zimbabwe uitgevoer is,
bevat waardevolle inligting oor tsetse bevolkingsdinamika. Die ontleding daarvan,
wat tot dusver gepubliseer is, kan egter verbeter word aangesien nie al
die inligting beskikbaar in die merkprosedure, gebruik is nie.
Ons het 'n individu-gebaseerde model saamgestel wat die lewens van individuele
tsetsevlieë en hul nageslagte volg, in besonder die volgorde waarop
individuele vlieë gevang en herkenbaar gemerk is. Ons het toegang tot omvattende
data van die tsetsevlieg merk-vrylaat-hervang eksperiment wat uitgevoer
is op Antelope Eiland, Karibadam, Zimbabwe. Ten einde die model te kalibreer
of om die model se geldigheid te bevestig, modelleer ons beide die groei
van die ingevoerde tsetse bevolking en die merk-hervangs metode. Ons vergelyk
die modeluitsette met die oorspronklike data en beveel prosesse aan wat
gevolg kan word om die model te kalibreer.
Dit is moontlik om 'n individu-gebaseerde model saam te stel wat tsetsevliegbevolkings
voldoende moduleer. Terwyl hierdie studie die modellering
van die merk-hervang data bestudeer, kan die individueel-gebaseerde model
ook gebruik word in meer algemene gevalle vir die modellering van die vermeerdering
en vermindering in vlieë getalle, veranderinge in die ouderdomstruktuur,
spesies en geslagverhoudings en die verwerwing van trypanosomen
infeksies deur individuele vlieë. Hierdie model kan dus gebruik word om die
effek te ondesoek van verskeie faktore op die tsetsevlieg en trypanosomen, populasiedinamiek
sowel as die prestasie van verskillende beheertegnieke rakende
vliegsterftes en siekte-oordrag.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/96685 |
| Date | 04 1900 |
| Creators | Ferreira, Roux-Cil |
| Contributors | Hargrove, J. W., Steel, S. J., Stellenbosch University. Faculty of Economic and Management Sciences. Dept. of Statistics and Actuarial Science. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | Unknown |
| Type | Thesis |
| Format | 55 pages : illustrations |
| Rights | Stellenbosch University |
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