Discussion

The World Health Organization (WHO) has identified Cryptosporidium spp. as globally the most common diarrhea-causing protozoan. The protozoan is the second most important cause of moderate-to-severe childhood diarrhea in developing countries whereas, in high-income countries it is an under-recognized pathogen in sporadic gastroenteritis. Humans can acquire Cryptosporidiuminfections through person-to-person transmission, zoonotic transmission, and waterborne/foodborne transmission. The potential for foodborne transmission of the protozoan parasite Cryptosporidium spp. is widely acknowledged. In this case, the role of food handlers is very important because they can make unsafe and hazardous foods for consumption. Indeed, outbreaks of Cryptosporidiosis Linked to a Foodhandler have been already observed in schools and in university campus. Since unhygienic preparation, storage and handling of food by infected individuals are a major cause for food-borne diseases, food handlers need to be screened before they are allowed to work in food establishments such as restaurants, hotels, food stores, factories or as helpers and cooks in private houses. Moreover, changes in nutritional habits have resulted in increased consumption of undercooked or raw foods, exposing consumers to parasites that proper food processing would otherwise reduce or eliminate. The aim of this study was to assess the prevalence of Cryptosporidium infection and its molecular characterization among foodhandlers in Qatar to check the relative importance of this transmission route in the epidemiology of cryptosporidiosis.

Stool samples were collected from workers related to food services. Samples were then subjected to DNA extraction and Real Time PCR detection. The positive RT-PCR products for Cryptosporidium spp. were analyzed by RFLP to identify the Cryptosporidium species. Specimens that contained Cryptosporidium parvum or Cryptosporidium hominis were further subtyped by DNA sequencing of the PCR product of the gp60 gene. The parasite was identified in 2.9% of the samples by RT-PCR targeting the 18S rRNA. PCR-RFLP analysis revealed distinctive banding patterns. The majority of isolates  (45.45%) were identified as C. parvum. 9% were positives for C. hominis, 27.27% were C. parvum + C. hominis, and 18.18% were C. parvum + C. meleagridis. All C. parvum isolates were classified as allele IId and were assigned as IIdA20G1. The identified C. hominis subtype was the less common IeA12G3T3 subtype. The predominance of the zoonotic subtype families of C. parvum IId in the Middle Eastern regions suggests that animal-to human transmission may be a common transmission route of Cryptosporidium. However, this postulation may be premature in view of findings of studies conducted in Kuwait.