First identification of Cryptosporidium parvum zoonotic subtype IIaA15G2R1 in diarrheal lambs in France

Molecular evaluation of Cryptosporidium spp. in sheep in southern Xinjiang, China

Cryptosporidium spp. are diarrheagenic intestinal parasites with multiple hosts worldwide. A total of 1252 fresh fecal samples of sheep were collected from 10 large-scale farms in southern Xinjiang. Based on the small subunit ribosomal (SSU rRNA) gene of Cryptosporidium, 100 Cryptosporidium-positive samples (8.0%, 100/1252) were detected by PCR. Nine out of 10 farms were positive for Cryptosporidium, with the highest infection rate being 18.4% (23/125) on farm 9 in Qira. The infection rates of Cryptosporidium in pre-weaned lambs, weaned lambs, fattening sheep, and adult sheep were 20.3% (61/301), 10.3% (34/329), 0.9% (3/327), and 0.7% (2/295), respectively. Three Cryptosporidium species were identified, namely, C. xiaoi (n = 61), C. parvum (n = 22), and C. ubiquitum (n = 17). Of them, C. xiaoi was detected on all positive farms and in different age groups of sheep. The subtypes of C. parvum and C. ubiquitum were identified by PCR at the 60 kDa glycoprotein (gp60) gene. Two C. parvum subtypes were identified: IIdA19G1 (n = 21) and IIdA15G1 (n = 1). One C. ubiquitum subtype was identified with XIIa (n = 17). These results indicated the common transmission and genetic diversity of Cryptosporidium in sheep in southern Xinjiang, and further investigations are needed on the zoonotic potential of C. parvum and C. ubiquitum in this region.

Cryptosporidium infections in sheep farms from Italy

Cryptosporidiosis is recognized as being a significant cause of gastrointestinal illness due to its wide range of vertebrate hosts, including humans. Infection with Cryptosporidium spp. is especially common in young domestic ruminants (calves, lambs and goat kids) and has been associated with economic losses worldwide. In contrast to cattle, to date, detailed studies on Cryptosporidium infections in sheep from Europe are still limited; thus, their importance as reservoirs of Cryptosporidium species with implications on animal and public health still needs to be clarified. This study evaluates the prevalence and zoonotic potential of Cryptosporidium spp. in sheep farms in Italy. A total of 915 individual faecal samples divided into three different animal categories were collected from 61 sheep farms. Each sample was examined by microscopy of faecal smears stained by modified Ziehl-Neelsen and by biomolecular techniques. Cryptosporidium oocysts were detected in 10.1% of the animals examined and in 34.4% of the farms. The prevalence of Cryptosporidium spp. was significantly higher (χ² = 51.854; P < 0.001) in diarrhoeic samples than in pasty or normal faeces. Genotype analyses showed the presence of two Cryptosporidium species: C. parvum and C. ubiquitum. Subtyping analysis of C. parvum isolates revealed the presence of subtypes IIa15G2R1 and IIdA20G1 and of subtype XIIa for C. ubiquitum. These findings have public health implications since both Cryptosporidium species identified are considered zoonotic, and C. parvum is the second-most common Cryptosporidium species infecting humans. Our data reveal that lambs, especially those excreting diarrhoeic faeces, may be important reservoirs of Cryptosporidium. We also highlight the need to establish adequate control and monitoring programmes for the control of this infection in sheep farms primarily through coprological monitoring.

Asymptomatic Cryptosporidium infections in ewes and lambs are a source of environmental contamination with zoonotic genotypes of Cryptosporidium parvum

Protozoan parasites of the Cryptosporidium genus cause severe cryptosporidiosis in newborn lambs. However, asymptomatic infections also occur frequently in lambs and ewes. In sheep, the most commonly detected Cryptosporidium species are C. ubiquitum, C. xiaoi and C. parvum. Due to a lack of relevant information about such infections in France, we investigated the situation on five dairy sheep farms in the Pyrénées-Atlantiques Department in south-western France in December 2017. Individual fecal samples were collected from 79 female lambs (5–17 days old) and their mothers (72 ewes). Oocysts were screened using Heine staining before and after Bailenger concentrations. Cryptosporidium species identification and genotyping were performed using real-time PCR and gp60 gene sequencing. No cases of clinical cryptosporidiosis were observed in the 79 lambs. Microscopically, Cryptosporidium spp. oocysts were observed in only one lamb on one farm (prevalence 1.3%) and one ewe on another farm (prevalence 1.4%). By contrast, Cryptosporidium spp. DNA was detected in 17 ewes (prevalence ranging from 10.5% to 50% depending on the farm) and in 36 lambs (prevalence ranging from 0% to 77.8% depending on the farm). Only zoonotic Cryptosporidium parvum IId and IIa genotypes were identified when genotyping was possible. Cryptosporidium ubiquitum and C. xiaoi were detected on one and three farms, respectively. We conclude that healthy young lambs and their mothers during the peripartum period could be a source of environmental contamination with oocysts.