Assessing the impact of environmental exposures and Cryptosporidium infection in cattle on human incidence of cryptosporidiosis in Southwestern Ontario, Canada

Investigating the relationship between extreme weather and cryptosporidiosis and giardiasis in Colorado: A multi-decade study using distributed-lag nonlinear models

Environmentally-mediated protozoan diseases like cryptosporidiosis and giardiasis are likely to be highly impacted by extreme weather, as climate-related conditions like temperature and precipitation have been linked to their survival, distribution, and overall transmission success. Our aim was to investigate the relationship between extreme temperature and precipitation and cryptosporidiosis and giardiasis infection using monthly weather data and case reports from Colorado counties over a twenty-one year period. Data on reportable diseases and weather among Colorado counties were collected using the Colorado Electronic Disease Reporting System (CEDRS) and the Daily Surface Weather and Climatological Summaries (Daymet) Version 3 dataset, respectively. We used a conditional Poisson distributed-lag nonlinear modeling approach to estimate the lagged association (between 0 and 12-months) between relative temperature and precipitation extremes and the risk of cryptosporidiosis and giardiasis infection in Colorado counties between 1997 and 2017, relative to the risk found at average values of temperature and precipitation for a given county and month. We found distinctly different patterns in the associations between temperature extremes and cryptosporidiosis, versus temperature extremes and giardiasis. When maximum or minimum temperatures were high (90th percentile) or very high (95th percentile), we found a significant increase in cryptosporidiosis risk, but a significant decrease in giardiasis risk, relative to risk at the county and calendar-month mean. Conversely, we found very similar relationships between precipitation extremes and both cryptosporidiosis and giardiasis, which highlighted the prominent role of long-term (>8 months) lags. Our study presents novel insights on the influence that extreme temperature and precipitation can have on parasitic disease transmission in real-world settings. Additionally, we present preliminary evidence that the standard lag periods that are typically used in epidemiological studies to assess the impacts of extreme weather on cryptosporidiosis and giardiasis may not be capturing the entire relevant period.

Detection and molecular characterization of Cryptosporidium spp. in dairy calves in Lisbon and Tagus Valley, Portugal

Cryptosporidium is a protozoan parasite with worldwide distribution, infecting a wide range of hosts with some zoonotic species. Calves have been identified as one of the most common reservoirs of this parasite. However, little is known about the genetics of Cryptosporidium in calves in Portugal. This study aimed to molecularly characterize infections of Cryptosporidium in pre-weaned calves from the Lisbon and Tagus Valley (LTV) in Portugal. Fifty-two samples were collected from calves from eight dairy and two beef farms in LTV, Portugal. Cryptosporidium oocysts were detected by Modified Ziehl-Neelsen staining (MZN) and direct immunofluorescent assay (DFA). MZN and DFA revealed the presence of Cryptosporidium oocysts in 40.4% (21/52) and 67.3% (35/52) samples, respectively. Positive samples were analyzed by PCR-RFLP of the 18 s rRNA gene for species identification. DNA amplification of the 18S rRNA gene was successful for 88.6% (31/35) of samples. Cryptosporidium parvum was identified in 96.8% (30/31) of the samples, and from one sample Cryptosporidium bovis was identified. Cryptosporidium parvum positive samples were subtyped by sequencing the PCR product of a partial fragment of the 60 kDa glycoprotein (gp60) gene. Subtype analysis of the C. parvum isolates revealed that all isolates belonged to subtype family IIa. Four subtypes were recognized within this subtype family, including the hyper-transmissible IIaA15G2R1 subtype that is the most frequently reported worldwide (27/30), IIaA14G2R1 (1/30), IIaA16G2R1 (1/30) and IIaA19G2R1 (1/30). To our knowledge, this is the first report of C. bovis, and C. parvum subtypes IIaA14G2R1 and IIaA19G2R1 in cattle in LTV, Portugal. The presence of the zoonotic C. parvum subtype in this study suggests that pre-weaned calves are likely to be a significant reservoir of zoonotic C. parvum, highlighting the importance of animal-to-human infection transmission risk. Further molecular studies are required to better understand the epidemiology of cryptosporidiosis in Portugal.

The occurrence and zoonotic potential of Cryptosporidium species in freshwater biota

BACKGROUND

Protozoan pathogens from the genus Cryptosporidium cause the diarrhoeal disease cryptosporidiosis in humans and animals globally. Freshwater biota could act as potential reservoirs or zoonotic sources of Cryptosporidium infections for livestock and people, but Cryptosporidium occurrence in aquatic biota is largely unexplored. The aim of this study was to investigate the occurrence of Cryptosporidium in a range of freshwater organisms in upland rivers across England and Wales.

METHODS

Fish were sampled by electrofishing, invertebrate larvae by kick sampling and the otter Lutra lutra and mink Mustela vison through faecal samples collected opportunistically as part of a nation-wide study. PCR targeting the small subunit ribosomal RNA gene was used to detect Cryptosporidium species.

RESULTS

Cryptosporidium occurred in just 0.8% of all the samples and in none of 73 samples from nine invertebrate genera. Cryptosporidium was detected in two of 2/74 fish samples (2.7%), both salmonids, and in 2/92 otter faecal samples (2.17%), but there were no positive samples in mink (0/24) or the bullhead Cottus gobio (0/16).

CONCLUSIONS

Low detection rate of human-infective Cryptosporidium species in aquatic fauna indicates they may present a low risk of contamination of some upland freshwaters.

Follow-up investigation into Cryptosporidium prevalence and transmission in Western European dairy farms

Cryptosporidium parvum is an enteric parasite and a major contributor to acute enteritis in calves worldwide, causing an important economic burden for farmers. This parasite poses a major public health threat through transmission between livestock and humans. Our previous pilot study in Western Europe revealed a high prevalence of Cryptosporidium in calves of dairy farms. In the sequel study herein, 936 faecal samples were collected from the same 51 dairy farms across Belgium, France, and the Netherlands. Following DNA extraction, Cryptosporidium screening was carried out using nested-PCR amplification targeting the SSU rRNA gene. All positive samples were sequenced, and phylogenetic analyses were used to identify the Cryptosporidium spp. present. The 60 kDa glycoprotein (gp60) gene was also sequenced to determine the C. parvum subtypes present. Prevalence of Cryptosporidium ranged from 23.3% to 25%, across the three countries surveyed. The parasite was found in most of the farms sampled, with 90.2% testing positive. Cryptosporidium parvum, C. bovis, C. ryanae and C. andersoni were all identified, with the former being the most predominant, representing 71.4% of all infections. Cryptosporidium parvum was associated with pre-weaned calves, while other species were associated with older animals. Subtyping of gp60 gene revealed nine subtypes, eight of which have previously been reported to cause clinical disease in humans. Similarly to the first study, vertical transmission was not a major contributor to Cryptosporidium spread. Our study highlights the need for further investigation into cryptosporidiosis transmission, and future studies will require a One Health approach to reduce the impact of this disease.

Intestinal Coccidian Infections in Cancer Patients: A Case Series

Introduction Coccidian protozoa and microsporidian fungi are opportunistic pathogens increasingly implicated in infections in immunosuppressed individuals. These parasites typically infect the intestinal epithelium, resulting in secretory diarrhea and malabsorption. The disease burden and timeline are both greater and longer among immunosuppressed patients. Therapeutic options for immunocompromised individuals are limited. As a result, we wanted to better characterize the disease course and treatment efficacy of these parasitic gastrointestinal infections. Methods We performed a single-center, retrospective MedMined (BD Healthsight Analytics, Birmingham, AL, USA) chart review of patients between January 2012 and June 2022 diagnosed with coccidian or microsporidian infections. Relevant data were collected from Cerner's PowerChart (Oracle Cerner, Austin, TX, USA). Descriptive analysis was performed with IBM SPSS Statistics (IBM Corp., Armonk, NY, USA), and Microsoft Excel (Microsoft, Redmond, WA, USA) was used to generate graphs and tables. Results In these 10 years, there were 17 patients with Cryptosporidium infections, four with Cyclospora infections, and no positive cultures for Cystoisospora belli or microsporidian infections. In both infections, the majority of patients experienced diarrhea, fatigue, and nausea, with vomiting, abdominal pain, appetite loss, weight loss, and fever occurring to a lesser degree. Nitazoxanide was the most common treatment for Cryptosporidium, while trimethoprim-sulfamethoxazole or ciprofloxacin were the treatments of choice for Cyclospora. Of the Cryptosporidium infections, three received combination therapy with azithromycin, immunoreconstitution, or IV immunoglobulins. Among the four Cyclospora-infected patients, one received combination therapy of ciprofloxacin and trimethoprim-sulfamethoxazole. Treatment lasted around two weeks, and 88% of Cryptosporidium patients and 75% of Cyclospora patients had a resolution of symptoms. Conclusion The most detected coccidian infection was Cryptosporidium, followed by Cyclospora, with the lack of Cystoisospora or microsporidian infections likely due to diagnostic limitations and prevalence. Cryptosporidium and Cyclospora likely caused their associated symptoms in most cases, with other possible etiologies, including graft-versus-host disease, medications, and feeding tubes. The small number of patients receiving combination therapy prohibited a comparison with monotherapy. In our patient population, though, there was a clinical response to treatment despite immunosuppression. While promising, additional randomized control experiments are required to fully understand the efficacy of parasitic treatments.

Environmental Factors Associated with Cryptosporidium and Giardia

Environmental factors significantly influence the transmission of intestinal protozoan diseases. Cryptosporidiosis and giardiasis are important zoonotic diseases characterized by diarrhea, and are mainly water or foodborne diseases caused by fecal-borne oocysts. The One Health approach effectively addresses environmentally influenced zoonotic diseases. However, the impact of environmental factors on the survival of Cryptosporidium/Giardia (oo)cysts or disease transmission is mostly uncharacterized. Associations between cryptosporidiosis and giardiasis incidence and environmental variables (e.g., climatic conditions, soil characteristics, and water characteristics) have been reported; however, the identified relationships are not consistently reported. Whether these are country-specific or global observations is unclear. Herein, we review the evidence for the influence of environmental factors on Cryptosporidium/Giardia and corresponding diseases from three perspectives: climatic, soil, and water characteristics. The (oo)cyst concentration or survival of Cryptosporidium/Giardia and the incidence of corresponding diseases are related to environmental variables. The associations identified varied among studies and have different levels of importance and lag times in different locations. This review summarizes the influence of relevant environmental factors on Cryptosporidium/Giardia from the One Health perspective and provides recommendations for future research, monitoring, and response.

Cryptosporidium in human-animal-environment interphase at Adama and Asella areas of Oromia regional state, Ethiopia

Background

In Ethiopia, several studies have reported the occurrence of Cryptosporidium infection in young calves, lambs, and HIV positive patients. However, research on cattle and sheep of all ages, as well as humans, has been limited.

Methods

A cross-sectional study was conducted to investigate the occurrence of Cryptosporidium in dairy cattle, sheep, humans, and manure samples. Dairy cattle and sheep were stratified according to their age groups and randomly sampled. Stool samples from volunteered dairy farm workers and rural household members were collected purposefully. A semi-structured questionnaire was also used to collect information about manure handling practices and socio-demographic variables. All collected samples were processed with the sugar floatation technique and the modified Ziehl–Neelsen staining method. Logistic regression was used to analyze the association of risk factors with the occurrence of Cryptosporidium in study subjects (p < 0.05).

Results

The overall prevalence of Cryptosporidium in dairy cattle, sheep, humans, and manure samples was 20.5%, 14%, 16%, and 13.20%, respectively. Cryptosporidium infection was significantly higher in dairy cattle aged 1–12 months and 13–36 months with odds of 3.48 and 3.07 times higher, respectively, compared to others. Similarly, its occurrence was 2.69 times higher in sheep aged 1–6 months than those above 6 months. And also, a higher average oocyst count (above 10 oocysts) per-field was observed in cattle aged 1–12 months, followed by sheep aged 1–6 months. Furthermore, the likelihood of infection was 13 times greater in farm workers compared to household members of smallholder farmers. In addition, the occurrence of oocysts was 22.8 times higher in manures from dairy cattle than that of sheep. About 16.8% of the study respondents had manure disposal pit, 98.1% of them used manure as fertilizer for crop and vegetable production without any treatment.

Conclusions

The study revealed the occurrence of Cryptosporidium infection in all age groups of dairy cattle and sheep, humans engaged in animal production. Occurrence of Cryptosporidium in manure suggests it potential contamination of environment and water sources.

Comparative evaluation of various diagnostic techniques for detection of Cryptosporidium infection from the faecal samples of diarrhoeic bovine calves

BACKGROUND

Cryptosporidium, an opportunistic, zoonotic, apicomplexan parasite, is one of the most common causes of diarrhea in neonatal bovine calves around the globe. Bovine calves act as a major source of infection by excreting huge numbers of highly resistant oocysts in faeces, which can survive for a long time in extreme environmental conditions. As low as ten oocysts can cause disease and mortality, leading to the requirement of an early and accurate diagnosis for proper and favorable prognosis, management, and control.

AIMS

The current study was conducted with the objective to evaluate various diagnostic techniques (acid fast staining, negative staining, fluorescent, ELISA, PCR, nested PCR, and qPCR) for the detection of Cryptosporidium in the faecal samples of diarrheic bovine calves.

METHODS

Two hundred diarrheic faecal samples from bovine calves were collected and subjected to these techniques for Cryptosporidium diagnosis. Results of these were evaluated for diagnostic comparison.

RESULTS

Out of 200 faecal samples evaluated, 24% (48/200) were detected positive for Cryptosporidium using a combination of two techniques as gold standard criteria. Cohen's kappa value indicated moderate to almost perfect agreement (0.616 to 0.986) among all the techniques used in the present study. Leishman staining showed the lowest sensitivity (54.17%), while nested PCR and qPCR showed the highest sensitivity (97.92%). Diagnostic specificity of all these tests ranged from 98.68 to 100%.

CONCLUSION

Auramine stain was used for the first time in the bovine calves in India for the detection and diagnostic comparison of Cryptosporidium. It showed strong agreement with the molecular as well as classical diagnostic techniques, and can be used for primary screening for better diagnosis.

Ocurrence of enteroparasites with zoonotic potential in animals of the rural area of San Andres, Chimborazo, Ecuador

OBJECTIVE

The aim of this research was the identification of the enteroparasites harbored by the animals of the San Andrés community, to evaluate their role as susceptible hosts and sources of infection for other animals, humans (zoonoses), as well as parasite forms spreaders to the environment in this rural area, located in the province of Chimborazo, Ecuadorian Andean region.

MATERIAL AND METHODS

The study was carried out combining 3 coproparasitological techniques: direct examination, Ritchie and Ziehl-Neelsen in 300 animal stool samples RESULTS: Blastocystis sp., Entamoeba spp., Giardia spp., Balantidium spp., Cryptosporidium spp., Ascaris spp., Toxocara spp., Ancylostoma spp., Strongylida, Hymenolepis nana and Echinococcus spp., were detected. Infection by protozoa (87.3%) was higher than helminths (31.0%). All cattle, sheep and guinea pigs were found parasitized, and the presence of Blastocystis sp., Entamoeba spp. and Cryptosporidium spp. by all groups of animals stands out. It is also remarkable the presence of Giardia spp. in swine (19.2%), big herbivores-livestock (11.5%), leporids (8.3%) and carnivores (5.9%); Balantidium spp. in swine (19.2%), big herbivores-livestock (5.8%) and carnivores (1.2%); Hymenolepis nana in guinea pigs (2.1%); and Toxocara spp. (15.7%), Echinococcus spp. (9.6%) and Ancylostoma spp. (6.0%) in dogs.

CONCLUSION

Animals from San Andrés have a wide spectrum of intestinal parasitic forms in their feces, being a source of infection to other animals and humans, and a source of contamination of the environment, posing a risk factor and reinforcing the idea of the need for more effective treatments and hygienic measures to improve livestock production and cutting its transmission.

A systematic review of waterborne and water-related disease in animal populations of Florida from 1999-2019

BACKGROUND

Florida's waters are a reservoir for a host of pathogens and toxins. Many of these microorganisms cause water-related diseases in people that are reportable to the Florida Department of Health. Our objective in this review was to ascertain which water-related pathogens and toxins of public health importance have been found in animal populations in Florida over the last twenty years.

METHODS

Nineteen databases were searched, including PubMed and Web of Science Core Collection, using keywords and search terms for the waterborne diseases, water-related vector-borne diseases, and water-based toxins reportable to the Florida Department of Health. For inclusion, peer-reviewed journal articles were to be written in English, published between January 1, 1999 and December 31, 2019, and contain primary research findings documenting at least one of the water-related pathogens or toxins of interest in an animal population within Florida during this same time frame.

RESULTS

Of over eight thousand initial search results, 65 studies were included for final analysis. The most common animal types implicated in the diseases of interest included marine mammals, fish and shellfish, wild birds, and livestock. Toxins or pathogens most often associated with these animals included toxin-producer Karenia brevis, vibriosis, Escherichia coli, and Salmonellosis.

DISCUSSION/CONCLUSION

Findings from this review elucidate the water-related disease-causing pathogens and toxins which have been reported within animal populations in recent Florida history. As most of these diseases are zoonotic, our results suggest a One Health approach is necessary to support and maintain healthy water systems throughout the state of Florida for the protection of both human and animal populations.

Cryptosporidium infection in cattle and humans in Ethiopia: A systematic review and meta-analysis

Cryptosporidium is an intracellular coccidian parasite causing gastrointestinal disturbances resulting in diarrhoea in humans and animals. It is more frequently detected in calves and early childhood, and one of the major causes of mortality in low-income countries. National estimates of Cryptosporidium infection rate in cattle and humans are lacking in Ethiopia. Therefore, this systematic review and meta-analysis estimated the prevalence and assess the risk factors of Cryptosporidium infection in cattle and humans over 20 years. Article searches were made using PubMed, HINARI, Research Gates, AJOLs and Google Scholar databases. Studies that met the inclusion criteria under the preferred reporting items for systematic reviews and meta-analyses (PRISMA) checklist were used. Random effects models and Inverse Variance Index were used to calculate the pooled prevalence of cryptosporidiosis and heterogeneity among studies, respectively. A total of 23 eligible studies published between 2000 and 2020 were selected for this study. The estimated pooled prevalence of cryptosporidiosis was found to be 16.2% and 11% in cattle and humans, respectively. Ten Cryptosporidium species were documented with cattle and human-based studies. C. andersoni, C. parvum, C. bovis and C. ryanae were the reported species in cattle. Similarly, in humans, seven types of Cryptosporidium species (such as C. parvum, C. hominis, C. viatorum, C. felis, C. meleagridis, C. canis and C. xiaoi) were recorded. C. parvum and C. hominis were the dominant and responsible species for human illness. Using gp60 gene locus analysis, various zoonotic C. parvum subgenotypes were determined in humans; but it was limited in anthroponotic C. hominis. In conclusion, the overall prevalence of Cryptosporidium infection in cattle and humans was high and linked with several risk factors. Thus, there is a need for further epidemiological and genetic diversity studies, and awareness of creations on the disease to provide strategies that mitigate the disease in cattle and humans.

Clinical and Laboratory Diagnosis of Cryptosporidiosis among Children with Acute Gastroenteritis at a Tertiary Hospital, Cairo, Egypt

BACKGROUND

Most studies on gastroenteritis have focused on viral and bacterial infections, while gastroenteritis where intestinal protozoan parasites may have played a role has not been well studied. This study was therefore, designed to assess the frequency and several potential risk factors for Cryptosporidium infection among children suffering from acute gastroenteritis and presented to a tertiary hospital in Cairo, Egypt. Effectiveness of modified Ziehl-Neelsen (MZN) and nested polymerase chain reaction (nPCR) for Cryptosporidium detection were evaluated as well.

METHODS

A cross-sectional study was performed during the period from July 2018 to December 2018, where 100 human diarrheic stool samples were collected from children aged 3 months up to 12 years old presented to Ain Shams University Pediatrics Hospital, Cairo, Egypt with acute gastroenteritis. Demographic and clinical data were obtained from the participants. Initial parasite screening was done using the MZN staining method, and microscopically examined for Cryptosporidium infection, while genotyping was based on molecular diagnostic assays using nPCR and sequencing for selected samples.

RESULTS

The overall frequency of Cryptosporidium infection was 5% using light microscopy, while 19% of samples were positive by nPCR. Cryptosporidium hominis was the only detected genotype. Clinical picture among cases were not significant in comparison to patients with other causes of gastroenteritis.

CONCLUSION

Cryptosporidium infection is more common below 5 years of age; however, clinical data are not enough for suspicion of infection. Nucleic acid-based methods are more sensitive and specific despite the high cost in developing countries. However, real estimation of Cryptosporidium disease burden is of an outmost importance to achieve prevention and detection of the Cryptosporidium species genetic diversity. Lay summaryCryptosporidium is a protozoan, which causes gastroenteritis in humans. It is most common below 5 years of age; however, diarrhea and vomiting characteristics are not different from other causes of gastroenteritis. General diagnostic methods are inadequate for detection of these infections. Nested polymerase chain reaction (nPCR) and sequencing are accurate methods for pathogen detection and species verification. Our study included 100 Egyptian children with acute gastroenteritis. The overall frequency of Cryptosporidium infection was 5% using light microscopy, while 19% of samples were positive by nPCR. The clinical picture of the children presenting with this disease was not significantly different from those presenting with gastroenteritis due to other causes. This emphasizes the importance of proper diagnosis to know the true burden of the disease.

Efficacy of halofuginone products to prevent or treat cryptosporidiosis in bovine calves: a systematic review and meta-analyses

A prior systematic review on the efficacy of halofuginone (HFG) treatment to prevent or treat cryptosporidiosis in bovine calves was inconclusive. We undertook an updated synthesis and meta-analyses on key outcomes for the treatment of calves with HFG. Evaluated outcomes were oocyst shedding, diarrhoea, mortality and weight gain. Experiments had to describe results for same age animals in contemporary arms. Most doses were 100-150 mcg kg-1 day-1. Results were subgrouped by study design, experiments with the lowest risk of bias and lack of industry funding. Eighteen articles were found that described 25 experiments. Most evidence came from randomized controlled trials in Europe. Significantly lower incidence of oocyst shedding, diarrhoea burden and mortality was reported when treatment started before calves were 5 days old. Most studies reported on outcomes for animals up to at least 28 days old. Publication bias was possible in all outcomes and seemed especially likely for diarrhoea outcomes. Beneficial results when HFG treatment was initiated in calves older than 5 days were also found. Prophylactic treatment to prevent cryptosporidiosis is effective in preventing multiple negative outcomes and is beneficial to calf health and will result in a reduction of environmental contamination by Cryptosporidium oocysts.

Molecular characterization of Cryptosporidium isolates from humans in Ontario, Canada

BACKGROUND

Cryptosporidiosis is a gastrointestinal disease with global distribution. It has been a reportable disease in Canada since 2000; however, routine molecular surveillance is not conducted. Therefore, sources of contamination are unknown. The aim of this project was to identify species and subtypes of Cryptosporidium in clinical cases from Ontario, the largest province in Canada, representing one third of the Canadian population, in order to understand transmission patterns.

METHODS

A total of 169 frozen, banked, unpreserved stool specimens that were microscopy positive for Cryptosporidium over the period 2008-2017 were characterized using molecular tools. A subset of the 169 specimens were replicate samples from individual cases. DNA was extracted directly from the stool and nested PCR followed by Sanger sequencing was conducted targeting the small subunit ribosomal RNA (SSU) and glycoprotein 60 (gp60) genes.

RESULTS

Molecular typing data and limited demographic data were obtained for 129 cases of cryptosporidiosis. Of these cases, 91 (70.5 %) were due to Cryptosporidium parvum and 24 (18.6%) were due to Cryptosporidium hominis. Mixed infections of C. parvum and C. hominis occurred in four (3.1%) cases. Five other species observed were Cryptosporidium ubiquitum (n = 5), Cryptosporidium felis (n = 2), Cryptosporidium meleagridis (n = 1), Cryptosporidium cuniculus (n = 1) and Cryptosporidium muris (n = 1). Subtyping the gp60 gene revealed 5 allelic families and 17 subtypes of C. hominis and 3 allelic families and 17 subtypes of C. parvum. The most frequent subtype of C. hominis was IbA10G2 (22.3%) and of C. parvum was IIaA15G2R1 (62.4%).

CONCLUSIONS

The majority of isolates in this study were C. parvum, supporting the notion that zoonotic transmission is the main route of cryptosporidiosis transmission in Ontario. Nonetheless, the observation of C. hominis in about a quarter of cases suggests that anthroponotic transmission is also an important contributor to cryptosporidiosis pathogenesis in Ontario.

Systematic review of modifiable risk factors shows little evidential support for most current practices in Cryptosporidium management in bovine calves

Cryptosporidiosis is common in young calves, causing diarrhoea, delayed growth, poor condition and excess mortality. No vaccine or cure exists, although symptomatic onset may be delayed with some chemoprophylactics. Other response and management strategies have focused on nutritional status, cleanliness and biosecurity. We undertook a systematic review of observational studies to identify risk or protective factors that could prevent Cryptosporidium parvum infection in calves. Included studies used multivariate analysis within cohort, cross-sectional or case-control designs, of risk factors among young calves, assessing C. parvum specifically. We tabulated data on characteristics and study quality and present narrative synthesis. Fourteen eligible studies were found; three of which were higher quality. The most consistent evidence suggested that risk of C. parvum infection increased when calves had more contact with other calves, were in larger herds or in organic production. Hard flooring reduced risk of infection and calves tended to have more cryptosporidiosis during warm and wet weather. While many other factors were not found to be associated with C. parvum infection, analyses were usually badly underpowered, due to clustering of management factors. Trials are needed to assess effects of manipulating calf contact, herd size, organic methods, hard flooring and temperature. Other factors need to be assessed in larger observational studies with improved disaggregation of potential risk factors.

An analecta of visualizations for foodborne illness trends and seasonality

Disease surveillance systems worldwide face increasing pressure to maintain and distribute data in usable formats supplemented with effective visualizations to enable actionable policy and programming responses. Annual reports and interactive portals provide access to surveillance data and visualizations depicting temporal trends and seasonal patterns of diseases. Analyses and visuals are typically limited to reporting the annual time series and the month with the highest number of cases per year. Yet, detecting potential disease outbreaks and supporting public health interventions requires detailed spatiotemporal comparisons to characterize spatiotemporal patterns of illness across diseases and locations. The Centers for Disease Control and Prevention's (CDC) FoodNet Fast provides population-based foodborne-disease surveillance records and visualizations for select counties across the US. We offer suggestions on how current FoodNet Fast data organization and visual analytics can be improved to facilitate data interpretation, decision-making, and communication of features related to trend and seasonality. The resulting compilation, or analecta, of 436 visualizations of records and codes are openly available online.

Dairy Calves in Uruguay Are Reservoirs of Zoonotic Subtypes of Cryptosporidium parvum and Pose a Potential Risk of Surface Water Contamination

Cryptosporidium parvum, a major cause of diarrhea in calves, is of concern given its zoonotic potential. Numerous outbreaks of human cryptosporidiosis caused by C. parvum genetic subtypes are reported yearly worldwide, with livestock or water being frequently identified sources of infection. Although cryptosporidiosis has been reported from human patients in Uruguay, particularly children, epidemiologic information is scant and the role of cattle as reservoirs of zoonotic subtypes of C. parvum has not been explored. In this study, we aimed to (a)-identify C. parvum subtypes infecting dairy calves in Uruguay (including potentially zoonotic subtypes), (b)-assess their association with calf diarrhea, (c)-evaluate their spatial clustering, and (d)-assess the distance of infected calves to surface watercourses draining the farmlands and determine whether these watercourses flow into public water treatment plants. Feces of 255 calves that had tested positive for Cryptosporidium spp. by antigen ELISA were selected. Samples had been collected from 29 dairy farms in seven Uruguayan departments where dairy farming is concentrated and represented 170 diarrheic and 85 non-diarrheic calves. Selected samples were processed by nested PCRs targeting the 18S rRNA and gp60 genes followed by sequencing to identify C. parvum subtypes. Of seven C. parvum subtypes detected in 166 calves, five (identified in 143 calves on 28/29 farms) had been identified in humans elsewhere and have zoonotic potential. Subtype IIaA15G2R1 was the most frequent (53.6%; 89/166), followed by IIaA20G1R1 (24.1%; 40/166), IIaA22G1R1 (11.4%; 19/166), IIaA23G1R1 (3.6%; 6/166), IIaA17G2R1 (3%; 5/166), IIaA21G1R1 (2.4%; 4/166), and IIaA16G1R1 (1.8%; 3/166). There were no significant differences in the proportions of diarrheic and non-diarrheic calves infected with any of the C. parvum subtypes. Two spatial clusters were detected, one of which overlapped with Uruguay's capital city and its main water treatment plant (Aguas Corrientes), harvesting surface water to supply ~1,700,000 people. Infected calves on all farms were within 20–900 m of a natural surface watercourse draining the farmland, 10 of which flowed into six water treatment plants located 9–108 km downstream. Four watercourses flowed downstream into Aguas Corrientes. Calves are reservoirs of zoonotic C. parvum subtypes in Uruguay and pose a public health risk.

A One Health Approach to Tackle Cryptosporidiosis

Cryptosporidiosis is a significant diarrhoeal disease in both people and animals across the world and is caused by several species of the protozoan parasite Cryptosporidium. Recent research has highlighted the longer-term consequences of the disease for malnourished children, involving growth stunting and cognitive deficits, and significant growth and production losses for livestock. There are no vaccines currently available to prevent the disease and few treatment options in either humans or animals, which has been a significant limiting factor in disease control to date. A One Health approach to tackle zoonotic cryptosporidiosis looking at new advances in veterinary, public, and environmental health research may offer several advantages and new options to help control the disease.

Cryptosporidium spp.: Human incidence, molecular characterization and associated exposures in Québec, Canada (2016-2017)

The aim of this study was to describe the epidemiology of human cryptosporidiosis in Québec from 2016 to 2017 and to identify possible exposures associated with the disease, and the dominant Cryptosporidium species in circulation. A descriptive analysis was performed on data collected from the provincial notifiable infectious diseases registry and the epidemiological investigation. Fecal sample were sent to the Laboratoire de santé publique du Québec for molecular characterization. In Québec, from January 1, 2016 to December 31, 2017, a total of 201 confirmed cases of cryptosporidiosis were notified. A peak in the number of reported cases was observed at the end of the summer. The regional public health department with the highest adjusted incidence rate for sex and age group for both years was that of Nunavik, in the north of Québec. A higher average annual incidence rate was observed for females between the ages of 20 to 34 years compared to males. Overall, for both males and females the distribution appeared to be bimodal with a first peak in children younger than five years old and a second peak in adults from 20 to 30 years of age. Molecular characterization showed that 23% (11/47) of cases were infected with C. hominis while 74% (35/47) were infected with C. parvum. Meanwhile, subtyping results identified by gp60 sequencing, show that all C. parvum subtypes belonged to the IIa family, whereas the subtypes for C. hominis belonged to the Ia, Ib, and Id families. Finally, the epidemiological investigation showed that diarrhea was the most common reported symptom with 99% (72/73) of investigated cases having experienced it. This first brief epidemiological portrait of cryptosporidiosis in Québec has allowed for the description, both at the provincial and regional level, of the populations that could be particularly vulnerable to the disease.

Cryptosporidium Infection: Epidemiology, Pathogenesis, and Differential Diagnosis

Cryptosporidium is a protozoan that infects a wide variety of vertebrates, including humans, causing acute gastroenteritis. The disease manifests with abdominal pain and diarrhea similar to that of choleric infection. In the immunocompromised hosts, the parasite causes prolonged infections that can also be fatal. For this reason, cryptosporidiosis is considered one of riskiest opportunistic infections for patients with acquired immunodeficiency syndrome. The best way to control the infection in these patients is setting up sensitive and specific diagnostic tests for epidemiological surveillance and morbidity reduction. Here, we summarized the general aspects of Cryptosporidium infection focusing on available diagnostic tools used for the diagnosis of cryptosporidiosis. Molecular methods currently available for its detection and progress in the development of new diagnostics for cryptosporidiosis are also discussed.

The Influence of Climate and Livestock Reservoirs on Human Cases of Giardiasis

Giardia duodenalis is an intestinal parasite which causes diarrhoeal illness in people. Zoonotic subtypes found in livestock may contribute to human disease occurrence through runoff of manure into multi-use surface water. This study investigated temporal associations among selected environmental variables and G. duodenalis occurrence in livestock reservoirs on human giardiasis incidence using data collected in the Waterloo Health Region, Ontario, Canada. The study objectives were to: (1) evaluate associations between human cases and environmental variables between 1 June 2006 and 31 December 2013, and (2) evaluate associations between human cases, environmental variables and livestock reservoirs using a subset of this time series, with both analyses controlling for seasonal and long-term trends. Human disease incidence exhibited a seasonal trend but no annual trend. A Poisson multivariable regression model identified an inverse association with water level lagged by 1 month (IRR = 0.10, 95% CI 0.01, 0.85, P < 0.05). Case crossover analysis found varying associations between lagged variables including livestock reservoirs (1 week), mean air temperature (3 weeks), river water level (1 week) and flow rate (1 week), and precipitation (4 weeks). This study contributes to our understanding of epidemiologic relationships influencing human giardiasis cases in Ontario, Canada.