Applied Maths Seminar: Smith? -- Modelling the ability of mass drug administration to interrupt soil-transmitted helminth transmission

Stacey Smith? (University of Ottawa) will be visiting us next week and will give a talk
on Wednesday 20th in Carslaw 451.  To be followed by lunch 1–2pm, all welcome,
students get free lunch.  

Title: Modelling the ability of mass drug administration to interrupt soil-transmitted
helminth transmission Abstract: The World Health Organization has recommended the
application of mass drug administration (MDA) in treating high prevalence neglected
tropical diseases such as soil-transmitted helminths (STHs), schistosomiasis, lymphatic
filariasis, onchocerciasis and trachoma.  MDA-which is safe, effective and
inexpensive-has been widely applied to eliminate or interrupt the transmission of STHs
in particular and has been offered to people in endemic regions without requiring
individual diagnosis.  We propose two mathematical models to investigate the impact of
MDA on the mean number of worms in both treated and untreated human subpopulations.  By
varying the efficacy of drugs, initial conditions of the models, coverage and frequency
of MDA (both annual and biannual), we examine the dynamic behaviour of both models and
the possibility of interruption of transmission.  Both models predict that the
interruption of transmission is possible if the drug efficacy is sufficiently high, but
STH infection remains endemic if the drug efficacy is sufficiently low.  In between
these two critical values, the two models produce different predictions.  By applying an
additional round of biannual and annual MDA, we find that interruption of transmission
is likely to happen in both cases with lower drug efficacy.  In order to interrupt the
transmission of STH or eliminate the infection efficiently and effectively, it is
crucial to identify the appropriate efficacy of drug, coverage, frequency, timing and
number of rounds of MDA.