&lt;i&gt;Cryptosporidium&lt;/i&gt; genotypes in children and calves living at the wildlife or livestock interface of the Kruger National Park, South Africa

Nada Abu Samra,John Frean,Ferran Jori,Bhavani Poonsamy,Peter N Thompson,Simone M Cacciò

doi:10.4102/ojvr.v83i1.1024

Abstract

Cryptosporidium infection is one of the most common causes of parasitic diarrhoea worldwide in cattle and humans. In developing countries, human cryptosporidiosis is most prevalent during early childhood and links between zoonotic infection and animal related activities have been demonstrated. This study investigated the prevalence and species/genotype distribution of Cryptosporidium among children (< 5 years) and calves (< 6 months) living in a rural farming area adjacent to the Kruger National Park in South Africa, where interactions between humans and wild and domestic animals are known to occur. Cryptosporidium oocysts were detected in 8/143 stool samples of children recruited within the hospital system (5.6%; 95% CI 2.4%, 10.7%) and in 2/352 faecal samples of calves (0.6%; 95% CI 0.1%, 2.0%) using the modified Ziehl–Neelsen (MZN) staining technique. Microscopy positive samples from children were further analysed by PCR targeting the 18S rRNA gene and identified as Cryptosporidium hominis (3/4) and Cryptosporidium meleagridis (1/4). Regardless of the microscopy outcome, randomly selected samples (n = 36) from calves 0–4 months of age were amplified and sequenced at the 18S rRNA gene using nested PCR. Two calves tested positive (5.6%; 95% CI 1.7%, 18.7%), and revealed the presence of Cryptosporidium parvum and Cryptosporidium bovis. The detection of only two zoonotic species (C. parvum in one calf and C. meleagridis in one child) suggests that zoonotic cryptosporidiosis is not currently widespread in our study area; however, the potential exists for amplification of transmission in an immunocompromised population.

Highlights

Cryptosporidium spp. are Apicomplexan parasites that infect a wide range of vertebrates, including humans
C. parvum is the only species of zoonotic importance identified in cattle and several outbreaks of C. parvum in people have been associated with infected calves in the United States and the United Kingdom (Gait et al 2008; Kiang et al 2006; Smith et al 2004)
Because no simultaneous investigation on Cryptosporidium spp. in young children and animals living at the wildlife/ livestock/human interface has been undertaken to date, the objective of this study was to estimate the prevalence and study the genetic diversity of Cryptosporidium spp. and to identify potential risk factors associated with cryptosporidiosis in young children and calves in an area of the Kruger National Park (KNP) wildlife/ livestock/human interface

Summary

Introduction

Cryptosporidium spp. are Apicomplexan parasites that infect a wide range of vertebrates, including humans. Other species of Cryptosporidium, including Cryptosporidium meleagridis, Cryptosporidium felis, and Cryptosporidium canis, are responsible for a smaller number of infections in humans and have mainly been reported in immunosuppressed patients (Xiao & Feng 2008). The zoonotic importance of Cryptosporidium spp. has been recognised for some time (Xiao & Feng 2008); the role of wild and domestic animals in the epidemiology of human cryptosporidiosis, in developing countries, is not completely understood. C. parvum is the only species of zoonotic importance identified in cattle and several outbreaks of C. parvum in people have been associated with infected calves in the United States and the United Kingdom (Gait et al 2008; Kiang et al 2006; Smith et al 2004). In Africa, in Egypt and Ethiopia, contact with cattle has been identified as a significant risk factor for the zoonotic transmission of C. parvum in children and HIV and/or AIDS patients (Adamu et al 2014; Helmy et al 2013)

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