Epidemiology of Cryptosporidiosis in France from 2017 to 2019

Abstract

Cryptosporidiosis is currently recognized worldwide as a leading cause of moderate to severe diarrhea. In Europe, large water- and foodborne outbreaks have been reported, highlighting the widespread distribution of the parasite and its important health impact. Surveillance networks have been progressively set up and the aim of this study was to present recent epidemiological data obtained in France from 2017 to 2019 by the National Reference Center—Expert Laboratory of cryptosporidiosis (Centre National de Référence–Laboratoire Expert cryptosporidioses CNR-LE). Data were obtained from online reports of volunteer network participants and stools were sent to the CNR-LE for species identification and GP60 genotyping. During this period, data from 750 online reports were available. Cryptosporidiosis occurred predominantly in young children (<5 years old) and in young adults, especially during late summer. Most patients were immunocompetent (60%), and deaths were reported only in immunocompromised patients. Cryptosporidium parvum was largely predominant (72% of cases) over C. hominis (24%) and some other uncommon species. C. parvum GP60 subtypes IIa and IId were the most represented, which suggests frequent zoonotic transmission. For C. hominis, subtypes IbA10G2 and IaA22R2 were predominant.

High Diversity of Cryptosporidium Species and Subtypes Identified in Cryptosporidiosis Acquired in Sweden and Abroad

“…In terms of the analysis of cases according to age, the observed bimodal distribution (Figure 1) supports previous observations [9], with a relatively high number of cases observed among infants and toddlers and with a second peak-and the largest one-in the 30-44-year-olds. Quite similar age distributions have been observed in studies from Denmark, France, and Canada, but with the second peak in the 20-35-year-olds [34,36,41]. The bimodal age distribution may reflect transmission between parents and their children; however, no such family clusters were detected during the present study.…”

“…Mixed C. hominis and C. parvum infection was observed only in 1 patient, and for 10 of the patients infected with C. parvum , the origin of infection was unknown or uncertain. The high occurrence of C. parvum compared with C. hominis observed in Sweden is similar to the situation in other industrial countries, such as France, Ireland, and Canada [ 34 , 35 , 36 ], although a higher percentage of C. hominis has been observed in Spain and Australia [ 37 , 38 ]. Shifting trends have been seen over time in the Netherlands and New Zealand, showing the importance of longitudinal studies [ 39 , 40 ].…”

Comparative Study of Eleven Mechanical Pretreatment Protocols for Cryptosporidium parvum DNA Extraction from Stool Samples

“…However, severe and prolonged infections are observed in immunocompromised patients and children under five [ 1 , 2 ]. The most frequent species isolated in humans are C. parvum and C. hominis , encompassing more than 90% of the cases of human cryptosporidiosis diagnosed in France [ 3 ]. Because treatment options remain limited, infection prevention and control measures are critical for the protection of vulnerable populations [ 4 ].…”

Comparative Performance of Eight PCR Methods to Detect Cryptosporidium Species

“…In 2017 in France, the National Reference Center-Expert Laboratory (CNR-LE) for cryptosporidiosis was set up, allowing the collection and interpretation of epidemiological data thanks to the participation of members of the network. Published data from the French CNR-LE for cryptosporidiosis show that: i) even with around 250 notified cases each year, cryptosporidiosis is still largely underestimated in France, ii) cryptosporidiosis is predominant in immunocompetent individuals and especially in young children and young adults, and iii) cryptosporidiosis is over-represented in the summer [ 5 , 6 ]. The routine diagnosis of cryptosporidiosis still relies on light microscopy examination for many laboratories [ 7 , 8 , 9 , 10 ].…”