https://hdl.handle.net/10646/3377 2026-04-09T16:40:41Z https://hdl.handle.net/10646/4028 Title: Modelling gender differences in drug abuse epidemics. Authors: Mushanyu, Josiah; Nyabadza, Farai; Ngarakana-Gwasira, Ethel T.; Mafuta, Phillip Abstract: Drug abuse is an issue of considerable concern due to its association with numerous public health problems. Mathematical models developed to describe the spread of drug abuse have generally assumed that the dynamics of drug use and treatment are substantially the same for women as men. However, research has revealed that the dynamics of women’s drug use and treatment are different in many ways from that of men’s. Understanding gender differences in patterns of drug use is essential to identify the influences of gender on the trends of drug abuse in order to develop appropriate and effective prevention programs.We formulate a sex structured compartmental model for the spread of drug abuse using nonlinear ordinary differential equations. The least squares curve fit routine (lsqcurvefit) in Matlab with optimization is used to estimate the parameter values. The model is fitted to data on individuals under substance abuse treatment centres of the Western Cape Province of South Africa and parameter values that give the best fit chosen. The projections carried out the long term trends of proportions for male and female rehabilitants. The results show that the proportion of male drug abusers in Cape Town is expected to continue to decrease whereas that of female drug abusers shall continue to increase but steadily. The estimated proportion of female drug abusers in specialist treatment centres of Cape Town was observed to be approximately 34% by the year 2030. 2018-01-11T00:00:00Z https://hdl.handle.net/10646/4027 Title: Assessing the role of climate change in Malaria transmission in Africa. Authors: Ngarakana-Gwasira, Ethel T.; Bhunu, Claver P.; Masocha, Mhosisi; Mashonjowa, Emmanuel Abstract: The sensitivity of vector borne diseases like malaria to climate continues to raise considerable concern over the implications of climate change on future disease dynamics. The problem of malaria vectors shifting from their traditional locations to invade new zones is of important concern. A mathematical model incorporating rainfall and temperature is constructed to study the transmission dynamics of malaria. The reproduction number obtained is applied to gridded temperature and rainfall datasets for baseline climate and future climate with aid of GIS. As a result of climate change, malaria burden is likely to increase in the tropics,the highland regions, and East Africa and along the northern limit of falciparum malaria. Falciparum malaria will spread into the African highlands; however it is likely to die out at the southern limit of the disease. 2016-02-23T00:00:00Z https://hdl.handle.net/10646/4026 Title: Transmission dynamics of schistosomiasis in Zimbabwe: A mathematical and GIS approach. Authors: Ngarakana-Gwasira, Ethel T.; Bhunu, Claver P.; Masocha, Mhosisi; Mashonjowa, Emmanuel Abstract: Temperature and presence of water bodies are known to influence the transmission dynamics of schistosomiasis. In this work, effects of water bodies (taken in context of rainfall patterns)and temperature from 1950 to 2000 are considered in the model. With the aid of Geographic Information System (GIS), the reproduction number is mapped on the Zimbabwean country.Results of the mapping show high reproduction numbers along the Lowveld and the Zambezi valley catchment area. High reproduction numbers suggest high levels of schistosomiasis. This result suggests more control efforts should be targeted in these areas with high reproduction numbers. 2015-11-15T00:00:00Z https://hdl.handle.net/10646/4016 Title: Assessing the impact of drug resistance on the transmission dynamics of Typhoid fever. Authors: Mushayabasa, Steady; Bhunu, Claver P.; Ngarakana-Gwasira, Ethel T. Abstract: Typhoid fever continues to be a major public health problem in the developing world. Antibiotic therapy has been the main stay of treating typhoid fever for decades. The emergence of drug-resistant typhoid strain in the last two decades has been a major problem in tackling this scourge. A mathematical model for investigating the impact of drug resistance on the transmission dynamics of typhoid fever is developed. The reproductive number for the model has been computed. Numerical results in this study suggest that when a typhoid outbreak occurs with more drug-sensitive cases than drug-resistant cases, then it may take 10–15 months for symptomatic drug-resistant cases to outnumber all typhoid cases, and it may take an average of 15–20 months for non symptomatic drug-resistant cases to outnumber all drug-sensitive cases. 2013-05-20T00:00:00Z