Cryptosporidium spp., prevalence, molecular characterisation and socio-demographic risk factors among immigrants in Qatar

Abstract

Background

The World Health Organization WHO has estimated that in developed countries, up to 30% of the population may suffer from foodborne diseases each year, and that in developing countries up to 2 million deaths per annum can be attributed to cryptosporidiosis. Reports have already emphasized the role of immigrants in outbreaks of parasitic diseases especially those working in food processing industries.

Methodology/Principal findings

Herein we assessed Cryptosporidium spp. infections among immigrants in Qatar with a special focus on food handlers and housemaids. The overall prevalence of Cryptosporidium spp. by q-PCR among 839 asymptomatic subjects was 4.5%. Based on the Gp60 gene, the majority of isolates were identified as C. parvum subtype IIdA20G1b. The positive sample for C. hominis was subtyped as IeA12G3T3. Seven mixed infections were also identified (four C. parvum + C. hominis, and three C. parvum + C. meleagridis). The prevalence of Cryptosporidium spp. did not differ significantly between the sexes or age classes but varied significantly between subjects affiliated to different religions with the lowest prevalence among the Muslims. Multifactorial analysis retained also marked significance with education, income, and a house contents index.

Conclusions/Significance

Our results contribute to a better understanding of the epidemiology of cryptosporidiosis and the risk factors associated with the likelihood of carrying this infection among immigrant workers from developing countries.

Author summary

Cryptosporidiosis is a diarrheal disease caused by the parasite Cryptosporidium with the potential of morbidity and mortality among fragile subjects. Although the frequency of this parasite is higher in under-developed countries, it can be a frequent source of diseases, in developed areas. This may be due, among other factors, to the immigration flows from poor endemic places to industrialized countries contributing thus to the parasite spread. Human illness was formerly thought to be caused by a single Cryptosporidium species, but advanced studies have demonstrated that it is caused by more than 20 different species. We examined characteristics and risk factors associated with Cryptosporidium among new immigrants in Qatar. We predominantly identified Cryptosporidium parvum as infecting species. We found that factors like religion, education, monthly income and the house contents play a major role in the parasite occurrence. Therefore, there is a need for better awareness about the parasite and about strategies for its eradication among the new immigrants in Qatar.