Summary
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.
Cystic echinococcosis (CE) is caused by the tapeworm, Echinococcus granulosus. The tapeworms resides in the small intestines of canids and the lifecycle involves both intermediate and definitive hosts. Humans are accidental intermediate hosts. Cystic echinococcosis is an economically important infection constituting a threat to public health, and is considered an emerging disease around the world. There are at least 10 Echinococcus strain types (G1 -G10), each exhibiting diversity of morphology, development and host range. The epidemiology of CE is poorly understood in South Africa. A retrospective data analysis of the National Health Laboratory Service (NHLS) laboratory information system on echinococcosis serology, microscopy and histopathology results in eight provinces (excluding KwaZula-Natal) showed an overall positivity rate in submitted diagnostic samples of 17.0% (1056/6211), with the Eastern Cape (30.4%), North West (19.0%) and Northern Cape (18.0%) provinces showing highest rates. The data showed considerable variability between provinces. The review also showed that most proven cases were negative on serology, implying that the actual number of patients could be underestimated. To our knowledge, no data exist about the prevalent strains of E. granulosus and this prospective study will attempt to fill that gap. The aim is to genotype strains causing the disease in South Africa. Two different polymerase chain reaction (PCR) methods will be used to respectively target the 12S rRNA and nad 1 genes. To date, three samples have been genotyped as G1, G5 and G6; suggesting diversity of strains prevalent in the country, but more data is needed for a clearer picture.
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