On the role of schistosome mating structure in the maintenance of drug resistant strains

The effects of drug treatment of human hosts upon a population of schistosome parasites depend upon a variety of factors. Previous models have shown that multiple strains of drug-resistant parasites are likely to be favored as the treatment rate increases. However, such models have neglected to account for the complex nature of schistosome mating biology. To more accurately account for the biology of these parasites, a simple mating structure is included in a multi-strain schistosome model, with parasites under the influence of drug treatment of their human hosts. Parasites are assumed to pay a cost for drug resistance in terms of reduced reproduction and transmission. The dynamics of the parasite population are described by a system of homogeneous differential equations, and the existence and stability of the exponential solutions for this system are used to infer the impact of drug treatment on the maintenance of schistosome genetic diversity.

[1]  K. P. Hadeler.  Pair formation in age-structured populations , 1989 .

[2]  M. Todd,et al.  Drugs for the control of parasitic diseases: current status and development in schistosomiasis. , 2003, Trends in parasitology.

[3]  K. P. Hadeler,et al.  Homogeneous models for sexually transmitted diseases , 1990 .

[4]  L. Chitsulo,et al.  The global status of schistosomiasis and its control. , 2000, Acta tropica.

[5]  Carlos Castillo-Chavez,et al.  Competitive Exclusion and Coexistence of Multiple Strains in an SIS STD Model , 1999, SIAM J. Appl. Math..

[6]  J. Gani,et al.  Mathematical Models for the Growth of Human Populations. , 1974 .

[7]  C. N. Brorn,et al.  WHO? , 1896 .

[8]  References , 1971 .

[9]  Carlos Castillo-Chavez,et al.  On the existence of stable pairing distributions , 1996 .

[10]  Zhilan Feng,et al.  Schistosomiasis models with density dependence and age of infection in snail dynamics. , 2002, Mathematical biosciences.

[11]  S. D. de Vlas,et al.  Worm burdens in schistosome infections. , 1996, Parasitology today.

[12]  T. Day,et al.  Resistance to praziquantel: direct evidence from Schistosoma mansoni isolated from Egyptian villagers. , 1999, The American journal of tropical medicine and hygiene.

[13]  Zhilan Feng,et al.  The influence of drug treatment on the maintenance of schistosome genetic diversity , 2001, Journal of mathematical biology.

[14]  K. P. Hadeler,et al.  Models for pair formation in bisexual populations , 1988, Journal of mathematical biology.