| Autor: |
Mutuku MW; School of Biological Sciences, College of Biological and Physical Sciences, University of Nairobi, Nairobi, Kenya.; Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya., Laidemitt MR; Department of Biology, Center for Evolutionary and Theoretical Immunology, Museum of Southwestern Biology, Parasitology Division, University of New Mexico, Albuquerque, New Mexico., Beechler BR; Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, Oregon., Mwangi IN; Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya., Otiato FO; Influenza Surveillance Program, Centers for Disease Control and Prevention, Nairobi, Kenya., Agola EL; Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya., Ochanda H; School of Biological Sciences, College of Biological and Physical Sciences, University of Nairobi, Nairobi, Kenya., Kamel B; Department of Biology, Center for Evolutionary and Theoretical Immunology, Museum of Southwestern Biology, Parasitology Division, University of New Mexico, Albuquerque, New Mexico., Mkoji GM; Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya., Steinauer ML; Department of Basic Medical Sciences, Western University of Health Sciences, Lebanon, Oregon., Loker ES; Department of Biology, Center for Evolutionary and Theoretical Immunology, Museum of Southwestern Biology, Parasitology Division, University of New Mexico, Albuquerque, New Mexico. |
| Abstrakt: |
Following a 4-year annual praziquantel (PZQ) treatment campaign, the resulting prevalence of Schistosoma mansoni was seen to differ among individual villages along the Kenyan shore of Lake Victoria. We have investigated possible inherent differences in snail-related aspects of transmission among such 10 villages, including six persistent hotspot (PHS) villages (≤ 30% reduction in prevalence following repeated treatments) located along the west-facing shore of the lake and four PZQ-responding (RESP) villages (> 30% prevalence reduction following repeated treatment) along the Winam Gulf. When taking into account all sampling sites, times, and water hyacinth presence/absence, shoreline-associated Biomphalaria sudanica from PHS and RESP villages did not differ in relative abundance or prevalence of S. mansoni infection. Water hyacinth intrusions were associated with increased B. sudanica abundance. The deeper water snail Biomphalaria choanomphala was significantly more abundant in the PHS villages, and prevalence of S. mansoni among villages both before and after control was positively correlated with B. choanomphala abundance. Worm recoveries from sentinel mice did not differ between PHS and RESP villages, and abundance of non-schistosome trematode species was not associated with S. mansoni abundance. Biomphalaria choanomphala provides an alternative, deepwater mode of transmission that may favor greater persistence of S. mansoni in PHS villages. As we found evidence for ongoing S. mansoni transmission in all 10 villages, we conclude that conditions conducive for transmission and reinfection occur ubiquitously. This argues for an integrated, basin-wide plan for schistosomiasis control to counteract rapid reinfections facilitated by large snail populations and movements of infected people around the lake. |
