An Update on Zoonotic Cryptosporidium Species and Genotypes in Humans

Abstract

The enteric parasite, Cryptosporidium is a major cause of diarrhoeal illness in humans and animals worldwide. No effective therapeutics or vaccines are available and therefore control is dependent on understanding transmission dynamics. The development of molecular detection and typing tools has resulted in the identification of a large number of cryptic species and genotypes and facilitated our understanding of their potential for zoonotic transmission. Of the 44 recognised Cryptosporidium species and >120 genotypes, 19 species, and four genotypes have been reported in humans with C. hominis, C. parvum, C. meleagridis, C. canis and C. felis being the most prevalent. The development of typing tools that are still lacking some zoonotic species and genotypes and more extensive molecular epidemiological studies in countries where the potential for transmission is highest are required to further our understanding of this important zoonotic pathogen. Similarly, whole-genome sequencing (WGS) and amplicon next-generation sequencing (NGS) are important for more accurately tracking transmission and understanding the mechanisms behind host specificity.

Molecular prevalence and subtyping of Cryptosporidium spp. in fecal samples collected from stray cats in İzmir, Turkey

“…Cryptosporidium spp. are obligate intracellular apicomplexan parasites distributed worldwide and infecting all vertebrates including humans and domestic animals [ 1 – 3 ]. The main transmission routes of Cryptosporidium are consumption of contaminated water and food or direct contact with infected animals and humans [ 3 ].…”

“…are obligate intracellular apicomplexan parasites distributed worldwide and infecting all vertebrates including humans and domestic animals [ 1 – 3 ]. The main transmission routes of Cryptosporidium are consumption of contaminated water and food or direct contact with infected animals and humans [ 3 ]. In humans, Cryptosporidium causes gastrointestinal disturbance presented with diarrhea, although subclinical cases are also common.…”

“…In humans, Cryptosporidium causes gastrointestinal disturbance presented with diarrhea, although subclinical cases are also common. It may cause serious disseminated infections in immunocompromised individuals [ 3 ]. Cryptosporidium infection is generally asymptomatic in cats but symptoms like diarrhea may occur especially in young and newborn kittens.…”

“…Among the 19 Cryptosporidium species ( C. hominis , C. parvum C. meleagridis , C. canis , C. felis , C. ubiquitum , C. cuniculus , C. viatorum , C. muris , C. andersoni , C. erinacei , C. tyzzeri , C. bovis , C. suis , C. scrofarum , C. occultus , C. xiaoi , C. fayeri and C. ditrichi ) and 4 genotypes ( Cryptosporidium chipmunk genotype I, mink genotype, skunk genotype and horse genotype), C. hominis and C. parvum are the most prevalently found in humans [ 3 ]. C. parvum is a zoonotic species whereas mainly anthroponotic C. hominis has been detected in different non-human animal species [ 5 , 6 ].…”

“…C. parvum is a zoonotic species whereas mainly anthroponotic C. hominis has been detected in different non-human animal species [ 5 , 6 ]. Cryptosporidium canis , C. felis , C. meleagridis , and C. ubiquitum are other significant zoonotic pathogens causing diseases in humans [ 3 ]. In cats, host-adapted C. felis is the main Cryptosporidium species, although C. parvum and C. muris have also been detected [ 7 – 12 ].…”