Risk factors for sporadic cryptosporidiosis: A systematic review and meta-analysis

Abstract

Cryptosporidium spp. is an important cause of gastrointestinal disease worldwide, responsible for 69 million cases of illness in 2016. Information on the sources and transmission pathways of human cryptosporidiosis results mainly from outbreak investigations. A systematic review and a meta-analysis of case-control and cohort studies were performed to determine the main risk factors associated with sporadic cryptosporidiosis. Suitable scientific articles were identified through a systematic literature search and subjected to a methodological quality assessment. From each study, odds ratio (OR) measures were extracted or calculated, as well as study characteristics such as population type, design, type of model and risk factor hierarchy. Mixed-effects meta-analysis models were adjusted by population type to appropriate data partitions. From 1985 identified references, the quality assessment stage was passed by 57 cohort and case-control studies focusing on sporadic cryptosporidiosis. The eligible studies were conducted between 1983 and 2016 and provided 568 OR categorized for meta-analysis. This meta-analysis identified travel, immunocompromising conditions, contact with infected humans, waterborne transmission (contact with recreational waters, wastewater, and consumption of untreated drinking water), contact with animals and food consumption as the relevant risk factors for sporadic cryptosporidiosis. With regards to food exposures, consumption of meat, dairy products (raw milk) and dishes consumed outside home were found significantly associated with cryptosporidiosis. The consumption of poorly washed fruits and vegetables significantly increases ORs. This meta-analysis reveals that some potential sources of Cryptosporidium such as shellfish or vegetables are under-investigated. Future case-control studies for sporadic cryptosporidiosis should include population at risk, and investigate other potential sources in relation to the genotype and the subtype of Cryptosporidium spp. 2018). Kirk et al. (2015) estimated that cryptosporidiosis resulted in 2159,331 DALYs in 2010. A clinical and epidemiological study involving 22,500 children from Africa and Asia revealed that Cryptosporidium spp. is one of four pathogens responsible for most of moderate to severe diarrhea in infants and toddlers (Kotloff et al., 2013). In 2016, Cryptosporidiosis was estimated to account for 10% of cases of diarrhea mortality among children under 5 years old (Troeger et al., 2018). There are numerous species and genotypes of Cryptosporidium, but human infection involves mainly two species: Cryptosporidium hominis, whose main host is humans and Cryptosporidium parvum which infects animal and ruminants. Transmission can occur through the fecal-oral route, involving direct (person-to-person transmission or contact with

WITHDRAWN: Synergism in sequential inactivation of Cryptosporidiumparvum with trypsin and UV irradiation

“…The global emission of Cryptosporidium oocysts to surface waters has been estimated at 3×10 17 oocysts per year (Hofstra et al 2013), which has been associated with high-pro le outbreaks. Cryptosporidium was estimated to be responsible for 69 million cases of illness, and 57203 deaths in 2016 (Kooh et al, 2021). During 2009 and 2017, 444 Cryptosporidiosis outbreaks occurred in US and resulted in 7465 cases, of which 56.7% were associated with contaminated river/reservoir and recreational water (Gharpure et al, 2019).…”

Determination of the Occurrence of Toxoplasma Gondii, Giardia Duodenalis and Cryptosporidium spp. in leafy Greens in Marrakech using a Molecular Method

“…The relative contribution of foodborne transmission in parasitic infections was poorly studied, but recent studies of meta-analysis of risk factors for parasitic infections identi ed the consumption of unwashed vegetables as a relevant risk factor for infection [45,48]. In this context, we wanted to investigate occurrence of protozoan in leafy greens in Morocco.…”

Protozoan Infections Acquired from Food or Drinking Water: An Update

“…The association of cryptosporidiosis with raw milk was significant for both mixed population and children. Associations with cryptosporidiosis were observed for barbecued foods, meat of non-specified origin, except beef, dishes prepared outside the home and raw milk [129]. In a retrospective study, eating raw foods was found to increase Cryptosporidium infection prevalence in China, despite the absence of reports of foods contaminated with Crysporidium oocysts in the country [127].…”

“…The association of dishes prepared outside the home and barbecued foods with infections by Cryptosporidium spp. can be linked to contamination by an infected handler during the preparation [129].…”

“…Fresh produce washed and not washed was not identified as a risk factor, despite being the main vehicle of foodborne cryptosporidiosis outbreaks. Indeed, several case-control studies suggested that the consumption of vegetables might lead to the acquisition of immunity following repeated exposure to low doses of oocysts [124,129]. Eating chicken, salad, tomatoes, and hard cheese was suggested to be a protective factor against Cryptosporidium infection [124].…”