domingo, 1 de julio de 2012

Genetic Characterization of Cryptospo... [Zoonoses Public Health. 2012] - PubMed - NCBI

Zoonoses Public Health. 2012 Jun 20. doi: 10.1111/j.1863-2378.2012.01507.x. [Epub ahead of print]

Genetic Characterization of Cryptosporidium spp. in Diarrhoeic Children from Four Provinces in South Africa.

Abu Samra N, Thompson PN, Jori F, Frean J, Poonsamy B, du Plessis D, Mogoye B, Xiao L.

Source

Epidemiology Section, Department of Production Animal Studies, University of Pretoria, Pretoria, South Africa CIRAD, UR AGIRs, Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria, Pretoria, South Africa National Institute for Communicable Diseases, South African Rotavirus Surveillance Programme, University of the Witwatersrand, Johannesburg, South Africa Division of Foodborne, Waterborne and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.

Abstract

The diversity of Cryptosporidium at species, subtype family and subtype level in diarrhoeic children was investigated in four provinces in South Africa. A total of 442 stool samples from children <5 years of age were collected under a large rotavirus surveillance programme and analysed by Ziehl-Neelsen acid-fast staining. Fifty-four (12.2%) were positive for Cryptosporidium, of which 25 were genotyped by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) and DNA sequence analyses of the 18S rRNA gene. The majority of genotyped specimens were identified as C. hominis (76%), and a high genetic diversity was found with five different C. hominis subtype families (Ia, Ib, Id, Ie and If). Cryptosporidium parvum was found in 20% of the isolates, and three subtype families were identified (IIc, IIe and IIb), with subtype family IIc being the most common. One specimen was identified as C. meleagridis of the subtype family IIId. These results are in accordance with findings from other developing countries and report for the first time the presence in South Africa of C. meleagridis, various subtypes of C. parvum and the subtype family Ie of C. hominis. The results suggest that C. hominis and anthroponotic C. parvum subtypes are the major cause of cryptosporidiosis in South Africa. Further molecular studies are needed to better understand the epidemiology and public health importance of Cryptosporidium in humans in South Africa.
© 2012 Blackwell Verlag GmbH.