caa a22 4500 386399514 CHVBK 20180307112153.0 cr unu---uuuuu 161130e198902 xx s 000 0 eng 10.1017/S0031182000059655 doi S0031182000059655 pii (NATIONALLICENCE)cambridge-10.1017/S0031182000059655 Spatial and temporal heterogeneity in the population dynamics of Bulinus globosus and Biomphalaria pfeifferi and in the epidemiology of their infection with schistosomes [Elektronische Daten] Populations of Bulinus globosus and Biomphalaria pfeifferi were studied in a river habitat in Zimbabwe over a period of 12 months. Data were obtained on the prevalences of infections of Schistosoma haematobium (also S. mattheei) and S. mansoni respectively. Population parameters showed the following patterns for both snail species. (1) A patchy distribution correlated with the distributions of aquatic plants. (2) Life-expectancies of only a few weeks. (3) Recruitment rates correlated with water temperature and showing a distinct seasonal peak. (4) Spatial variation in recruitment. (5) A redistribution of snails during the rainy season. Epidemiological parameters showed the following patterns. (1) Large seasonal variations in the prevalence of patent infections. (2) Evidence from size-prevalence curves that suggests a variable force-of-infection from man to snail, correlated with water temperature. (3) Prevalences of infection that were higher in the vicinity of (±60 m from) major water contact sites. Local prevalences of infection for B. globosus sometimes exceeded 50% and may have approached 100% if pre-patent infections are included. Snail numbers may limit transmission at these locations. Attention is drawn to the need to make field observations at an appropriate spatial scale and also to the implications for the effectiveness of focal snail control as a means of reducing transmission. Copyright © Cambridge University Press 1989 Bulinus globosus nationallicence Biomphalaria pfeifferi nationallicence population dynamics nationallicence epidemiology nationallicence Schistosoma haematobium nationallicence Schistosoma mansoni nationallicence Woolhouse M. E. J. Department of Pure and Applied Biology, Imperial College, Prince Consort Road, London SW7 2BB and Department of Biological Sciences, University of Zimbabwe, P.O. Box MP 167, Mount Pleasant, Harare, ZW Chandiwana S. K. Blair Research Laboratories, P.O. Box 8105, Causeway, Harare, ZW Parasitology Cambridge University Press 98/1(1989-02), 21-34 0031-1820 98:1<21 1989 98 PAR https://doi.org/10.1017/S0031182000059655 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S0031182000059655 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Woolhouse M. E. J. Department of Pure and Applied Biology, Imperial College, Prince Consort Road, London SW7 2BB and Department of Biological Sciences, University of Zimbabwe, P.O. Box MP 167, Mount Pleasant, Harare, ZW NATIONALLICENCE 700 1- Chandiwana S. K. Blair Research Laboratories, P.O. Box 8105, Causeway, Harare, ZW NATIONALLICENCE 773 0- Parasitology Cambridge University Press 98/1(1989-02), 21-34 0031-1820 98:1<21 1989 98 PAR CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge