This Article Full Text (PDF) Other Versions of this Article: AEM.01576-08v1 74/23/7227    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Google Scholar Articles by Tanrverdi, S. Articles by Widmer, G. PubMed PubMed Citation Articles by Tanrverdi, S. Articles by Widmer, G. Agricola Articles by Tanrverdi, S. Articles by Widmer, G.

 Previous Article  |  Next Article 

Appl. Environ. Microbiol. doi:10.1128/AEM.01576-08
Copyright (c) 2008, American Society for Microbiology and/or the Listed Authors/Institutions. All Rights Reserved.

Inferences about the global population structure of Cryptosporidium parvum and Cryptosporidium hominis

Sultan Tanrverdi, Alex Grinberg, Rachel M. Chalmers, Paul R. Hunter, Zorana Petrovic, Donna E. Akiyoshi, Eric London, Linghui Zhang, Saul Tzipori, James K. Tumwine, and Giovanni Widmer^*

Tufts Cummings School of Veterinary Medicine, Division of Infectious Diseases, North Grafton, Massachusetts, 01536; Massey University, Institute of Veterinary, Animal and Biomedical Sciences, Palmerston North, New Zealand; UK Cryptosporidium Reference Unit, NPHS Microbiology Swansea, Singleton Hospital, Swansea, United Kingdom; School of Medicine, Health Policy and Practice, University of East Anglia, Norwich, United Kingdom; Faculty of Veterinary Medicine, University of Belgrade, Serbia; Department of Pediatrics and Child Health, Makerere University Medical School and Mulago Hospital, Kampala, Uganda

^* To whom correspondence should be addressed. Email: giovanni.widmer{at}tufts.edu.

	Abstract

Cryptosporidium parvum and C. hominis are two related species of apicomplexan protozoa responsible for the majority of human cases of cryptosporidiosis. In spite of their considerable public health impact, little is known about the population structure of these species. In this study, a battery of C. parvum and C. hominis isolates from seven countries was genotyped using a nine-locus DNA subtyping scheme. To assess the existence of geographical partitions, the multilocus genotype data were mined using a cluster analysis based on the Nearest Neighbor principle. Within each country, the population genetic structures were explored by combining diversity statistical tests, linkage disequilibrium and eBURST analysis. For both parasite species, a quasi-complete phylogenetic segregation was observed among countries. Cluster analysis accurately identified recently introduced isolates. Rather than conforming to a strict paradigm of either a clonal or a panmictic population structure, data are consistent with a flexible reproductive strategy characterised by the co-occurrence of both propagation patterns. The relative contribution of each pathway appears to vary between the regions, perhaps dependent on the prevailing ecological determinants of transmission.