Risk Factors For Cryptosporidiosis Research Articles

Intestinal apicomplexan parasitoses among a hospital-based population in Honduras, 2013-2019.

: Introduction: Intestinal apicomplexa protozoa are a recognized cause of gastroenteritis. They are endemic in Honduras and their epidemiology varies in different population groups.Objective: To identify risk factors for cyclosporiasis, cryptosporidiosis, and cystoisosporiasis.Materials and methods: We conducted a case-control study in a hospital-based population. We performed the diagnosis using the modifed Ziehl-Neelsen staining technique and collected the information from laboratory records and clinical charts.Results: Cyclosporiasis was associated with diarrhea (OR=2.28; 95%CI: 1.10-4.89), weight loss (OR=12.7; 95%CI: 2.49-122.00), watery stools (OR=2.42; 95%CI: 1.26-4.65), and infection with another protozoan (OR=3.13; 95%CI: 1.66-5.95). Cryptosporidiosis was associated with HIV infection (OR=15.43; 95%CI: 3.34-71.22), diarrhea (OR=3.52; 95%CI: 1.40-9.40), lymphopenia (OR=6.16; 95%CI: 1.99-18.98), and green color stools (OR=3.00; 95%CI: 1.23-7.30). Cystoisosporiasis was associated with HIV infection (OR=11.20; 95%CI: 3.53-35.44), diarrhea (OR=7.30; 95%CI: 1.89-28.52), leukopenia (OR=4.28; 95%CI: 1.33-13.75), green color stools (OR=11.59; 95%CI: 1.16-558.60), and Charcot-Leyden crystals (OR=11.59; 95%CI: 1.16-558.60).Conclusions: In this hospital-based population from Honduras, HIV infection was a risk factor for cryptosporidiosis and cystoisosporiasis, but not for cyclosporiasis.

Veterinary Students Have a Higher Risk of Contracting Cryptosporidiosis when Calves with High Fecal Cryptosporidium Loads Are Used for Fetotomy Exercises.

An outbreak of cryptosporidiosis among veterinary students performing fetotomy exercises on euthanized calves took place in September 2018 in Denmark. A prospective cohort investigation was performed to identify risk factors and provide guidance for preventing outbreaks of cryptosporidiosis in this setting. Ninety-seven students attended the fetotomy exercises and completed a questionnaire about symptoms and potential risk behavior. Real-time PCR was used to detect Cryptosporidium spp. in stool samples from students and to quantify the fecal parasite load in the calves used for the exercises. gp60 subtyping was carried out for the Cryptosporidium-positive samples. Our case definition was based on participation in a fetotomy exercise, reported symptoms, and laboratory results. Eleven laboratory-confirmed or probable cases (11%) were identified in two outbreaks during the prospective study period, with attack rates of 4/10 (40%) and 7/9 (78%), respectively. The risk factors for cryptosporidiosis we identified were performing the exercise on a diarrheic calf, reporting visible fecal contamination on the personal protective equipment (PPE), and reporting problems with PPE during the exercise. Cryptosporidium parvum IIaA15G2R1 was detected in both cases and calves. A significantly higher proportion of the calves aged 7 days old and above were positive compared with younger calves. Furthermore, a high fecal Cryptosporidium load in a calf was associated with a higher probability of an outbreak among the students. Based on our results, using noninfected calves for the exercises, appropriate use of PPE, and thorough hand hygiene are recommended to reduce the risk of contracting cryptosporidiosis in connection with fetotomy exercises.IMPORTANCECryptosporidium spp. can cause severe diarrhea in infected individuals. Cryptosporidium parvum is zoonotic, and cattle are the main reservoir. In several countries, outbreaks of cryptosporidiosis have occurred in veterinary students after handling calves. We carried out a 1-year-long prospective study to investigate the occurrence of these recurrent cryptosporidiosis outbreaks in Denmark. Our investigation used a One Health approach and combined comprehensive epidemiological approaches and laboratory methods applied to both students and calves in the setting of the fetotomy exercises. Two outbreaks took place during the study period; additionally, we retrospectively identified two more suspected outbreaks prior to the study period. The results illustrated a high risk of contracting cryptosporidiosis among veterinary students in the setting of the fetotomy exercises, especially when using calves with high fecal Cryptosporidium loads. Our data can be used to inform future efforts to prevent transmission of Cryptosporidium parvum to students during fetotomy exercises.

Cryptosporidium and Cryptosporidiosis: The Perspective from the Gulf Countries.

The present review discusses the burden of cryptosporidiosis in the Gulf Cooperation Council (GCC), which is underreported and underestimated. It emphasizes that the Cryptosporidium parasite is infecting inhabitants and expatriates in the Gulf countries. Children under 5 years are a vulnerable group that is particularly affected by this parasitic disease and can act as carriers, who contribute to the epidemiology of the disease most probably via recreational swimming pools. Various risk factors for cryptosporidiosis in the GCC countries are present, including expatriates, predisposing populations to the infection. Water contamination, imported food, animal contact, and air transmission are also discussed in detail, to address their significant role as a source of infection and, thus, their impact on disease epidemiology in the Gulf countries’ populations.

Epidemiology and Risk Factors for Cryptosporidiosis in Children From 8 Low-income Sites: Results From the MAL-ED Study.

Cryptosporidium species are enteric protozoa that cause significant morbidity and mortality in children worldwide. We characterized the epidemiology of Cryptosporidium in children from 8 resource-limited sites in Africa, Asia, and South America. Children were enrolled within 17 days of birth and followed twice weekly for 24 months. Diarrheal and monthly surveillance stool samples were tested for Cryptosporidium by enzyme-linked immunosorbent assay. Socioeconomic data were collected by survey, and anthropometry was measured monthly. Sixty-five percent (962/1486) of children had a Cryptosporidium infection and 54% (802/1486) had at least 1 Cryptosporidium-associated diarrheal episode. Cryptosporidium diarrhea was more likely to be associated with dehydration (16.5% vs 8.3%, P < .01). Rates of Cryptosporidium diarrhea were highest in the Peru (10.9%) and Pakistan (9.2%) sites. In multivariable regression analysis, overcrowding at home was a significant risk factor for infection in the Bangladesh site (odds ratio, 2.3 [95% confidence interval {CI}, 1.2-4.6]). Multiple linear regression demonstrated a decreased length-for-age z score at 24 months in Cryptosporidium-positive children in the India (β = -.26 [95% CI, -.51 to -.01]) and Bangladesh (β = -.20 [95% CI, -.44 to .05]) sites. This multicountry cohort study confirmed the association of Cryptosporidium infection with stunting in 2 South Asian sites, highlighting the significance of cryptosporidiosis as a risk factor for poor growth. We observed that the rate, age of onset, and number of repeat infections varied per site; future interventions should be targeted per region to maximize success.

Epidemiology of Cryptosporidium in Pediatric Diarrheal Illnesses.

Cryptosporidium spp. is a zoonotic infection, now being recognized as a significant cause of diarrhea in both immunocompetent and immunocompromised hosts. However, there still exist significant knowledge gaps in its estimated global burden, epidemiology, diagnosis and management. A semi-systematic search was performed across PubMed to select studies on epidemiological burden of cryptosporidium diarrhea using the following keywords- ['crytosporidiosis' OR 'cryptosporidium'] AND ['diarrhea' OR 'diarrhoea']. Articles were included if participants were 'Humans', belonged to pediatric (0-18 y) age group, and were published after 1990. The results were compiled separately for acute and persistent diarrhea. Cryptosporidium spp is commonly detected in stools of both cases (acute/ persistent diarrhea) and asymptomatic controls. The prevalence is higher in children with diarrhea than non-diarrheal controls (1.7-35% vs 0.3-15%); varying widely across different studies. The positivity rate is higher in younger children (<2 years) suffering from diarrhea. The main symptoms associated with cryptosporidiosis include fever, vomiting and abdominal pain with propensity for prolonged duration of diarrhea. It predisposes to malnutrition, which is also a risk factor for cryptosporidiosis. The prevalence is higher in HIV positive patients; certain socio-demographic factors play a more important role than mere geographical distribution for infection. The high positivity rates during both acute and persistent diarrhea highlights the need to suspect this infection even in immunocompetent children.

Prevalence and risk factors for cryptosporidiosis: a global, emerging, neglected zoonosis

Abstract Background Cryptosporidiosis is a zoonotic disease caused by the important parasitic diarrheal agent Cryptosporidium spp. Cryptosporidiosis occurs in all classes of animals and man with a rapidly expanding host range and increased importance since the occurrence of human immunodeficiency virus/acquired immunodeficiency syndrome in man. Objectives To review the global picture of cryptosporidiosis in man and animals with emphasis on prevalence and risk factors. Methods Current relevant literature on cryptosporidiosis was reviewed. Results Cryptosporidiosis is widely distributed and the risk factors vary from one region to another with hygiene and immune status as important risk factors. Conclusions Cryptosporidium spp. associated mortality has not only been reported in immune-compromised patients, but also in immune-competent patients. Yet in many countries not much attention is paid to the control and prevention of this infection in animals and man. The neglect of this disease despite the serious threat it poses to animals, their husbandry, and humans, has led the World Health Organization to list it among globally neglected diseases. To control and prevent this infection more effort needs to be directed at controlling the risk factors of the infection in man and animals.

Cryptosporidiosis: A Disease of Tropical and Remote Areas in Australia.

Cryptosporidiosis causes gastroenteritis and is transmitted to humans via contaminated water and food, and contact with infected animals and people. We analyse long-term cryptosporidiosis patterns across Australia (2001–2012) and review published Australian studies and jurisdictional health bulletins to identify high risk populations and potential risk factors for disease. Using national data on reported cryptosporidiosis, the average annual rate of reported illness was 12.8 cases per 100 000 population, with cycles of high and low reporting years. Reports of illness peak in summer, similar to other infectious gastrointestinal diseases. States with high livestock densities like New South Wales and Queensland also record a spring peak in illnesses. Children aged less than four years have the highest rates of disease, along with adult females. Rates of reported cryptosporidiosis are highest in the warmer, remote regions and in Aboriginal and Torres Strait Islander populations. Our review of 34 published studies and seven health department reports on cryptosporidiosis in Australia highlights a lack of long term, non-outbreak studies in these regions and populations, with an emphasis on outbreaks and risk factors in urban areas. The high disease rates in remote, tropical and subtropical areas and in Aboriginal and Torres Strait Islander populations underscore the need to develop interventions that target the sources of infection, seasonal exposures and risk factors for cryptosporidiosis in these settings. Spatial epidemiology can provide an evidence base to identify priorities for intervention to prevent and control cryptosporidiosis in high risk populations.

Risk factors for cryptosporidiosis among children in a semi urban slum in southern India: a nested case-control study.

The risk factors for acquisition of cryptosporidial infection in resource-poor settings are poorly understood. A nested case-control study was conducted to assess factors associated with childhood cryptosporidiosis (detected by stool polymerase chain reaction) in an endemic, Indian slum community using data from two community-based studies with 580 children followed prospectively until their second birthday. Factors were assessed for overall cryptosporidiosis (N = 406), and for multiple (N = 208), asymptomatic (N = 243), and symptomatic (N = 163) infections, respectively. Presence of older siblings (odds ratio [OR] = 1.88, P = 0.002) and stunting at 6 months of age (OR = 1.74, P = 0.019) were important risk factors for childhood cryptosporidiosis. Always boiling drinking water before consumption, the use of a toilet by all members of the family, and maternal age ≥ 23 years were protective. These results provide insights into acquisition of childhood cryptosporidiosis in settings with poor environmental sanitation, contaminated public water supply systems, and close human-animal contact. Disease control strategies will require a multifaceted approach.

Prevalence, molecular characteristics and risk factors for cryptosporidiosis among Iranian immunocompromised patients

Cryptosporidium spp. is a major cause of diarrhea in developing countries, mainly affecting people with compromised immune systems in general and HIV-infected individuals with low CD4 + T-cell counts in particular. This infection is self-limiting in healthy persons; however, it can be severe, progressive and persistent in those who are immunocompromised. There are few published studies concerning cryptosporidiosis and Cryptosporidium genotypes in Iranian immunocompromised patients and none of them describe risk factors. This study was undertaken to identify prevalence, genotypes and risk factors for cryptosporidiosis in immunocompromised patients. Three fecal samples were obtained at two day intervals from each of the 183 patients and processed with modified Ziehl-Neelsen staining methods and 18S rRNA gene amplification and sequencing. The overall infection prevalence was 6%. Cryptosporidium parvum was identified in isolates from five HIV-infected patients, one patient who had undergone bone marrow transplantation and one with chronic lymphocytic leukemia. Cryptosporidium hominis was identified in isolates from two HIV-infected patients and two patients with acute lymphocytic leukemia. According to univariate analysis, the statistically significant factors were diarrhea (OR = 21.7, CI = 2.83-78.4, P= 0.003), CD4 + lymphocytes less than 100 cells/mm(3) (OR = 41.3, CI = 13.45-114.8, P < 0.0001), other microbial infections (OR = 7.1321.7, CI = 1.97-25.73, P = 0.006), weight loss (OR = 73.78, CI = 15.5-350, P < 0.0001), abdominal pain (OR = 10.29, CI = 2.81-37.74.4, P= 0.001), dehydration (OR = 72.1, CI = 17.6-341.5, P < 0.0001), vomiting (OR = 4.87, CI = 1.4-16.9, P= 0.015), nausea (OR = 9.4, CI = 2.38-37.2, P < 0.001), highly active antiretroviral therapy (OR = 0.089, CI = 0.01-0.8, P= 0.015) and diarrhea in household members (OR = 7.37, CI = 2.04-26.66, P= 0.001). After multivariate analysis and a backward deletion process, only < 100 CD4 + T-lymphocytes/mm(3) maintained a significant association with infection. The authors recommend that this infection should be suspected in patients with diarrhea, weight loss and dehydration in general and in diarrheal individuals with < 100 CD4 + T-lymphocytes/mm(3).

Control of cryptosporidiosis in neonatal calves: Use of halofuginone lactate in two different calf rearing systems

To date there is no effective treatment for bovine cryptosporidiosis. This study describes the use of halofuginone lactate in preventing cryptosporidiosis in naturally infected neonatal calves on a dairy farm with a high prevalence of infection. The animals were kept in two different calf rearing systems. A randomized double-blind trial was carried out with 32 naturally infected calves, divided into four groups. The two prophylactic halofuginone lactate treated groups were kept in either individual or group pens. Similarly, the animals receiving the placebo were housed in either individual pens or together in a large pen. A total of ten faecal samples were collected periodically during the 28 days study from each calf and tested for the presence of Cryptosporidium spp. using microscopic and molecular methods. Generalized estimating equations models were used to determine if the effects of the various treatments and/or rearing systems on the presence of diarrhoea and infection were statistically significant. Further analysis (classification trees models) was carried out to explore possible risk factors for cryptosporidiosis and interactions between treatments and rearing systems. Halofuginone lactate was shown to be effective in reducing clinical signs of cryptosporidiosis and environmental contamination. However, the treatment did not delay the onset of diarrhoea and did not reduce the risk of infection amongst calves reared together in a highly contaminated environment. The use of halofuginone lactate in combination with good hygienic measures, such as rearing animals in clean individual pens, was the most effective method to reduce the risk of cryptosporidiosis amongst 7–13 days old calves. It was concluded that the control of the parasite could be achieved by the combination of using effective preventive drugs, such as halofuginone lactate and good animal husbandry procedures.

Investigation into the Prevalence of Cryptosporidium Infection in Calves among Small-Holder Dairy and Traditional Herds in Tanzania

A cross-sectional study was conducted to determine prevalence and risk factors of cryptosporidiosis in bovine from two contrasting production system in and around Tanga municipality between May 2003 and January 2004. The study populations comprised 117 calves aged ≤3 months, randomly selected from 44 smallholders dairy and traditional managed herds, respectively. Individual calf and herd-level information was collected using a structured questionnaire and feacal samples were screened for Cryptosporidium spp oocysts using the modified Ziehl-Neelsen method. Overall, 35% of the calves in the study were shedding Cryptosporidium spp oocysts, with at least one positive calf detected in 54.5% of herds. Independent risk factors for cryptosporidiosis were: age ≥1 to ≤2 months and level of cleanness of calf house floor categorized as dirty (P < .05). Similarly an increases risk of Cryptosporidium spp infection was found in calves from smallholder dairy units compared to traditional herds (P < .05). The finding highlights that Cryptosporidium spp is prevalent among calves in the area under study. The high prevalence of cryptosporidiosis detected in this study suggests that it may have a significant impact on livestock industry and that the close interaction between cattle and human may play a role in zoonotic transmission to humans.

Epidemiology of Cryptosporidiosis in North American Travelers to Mexico

We studied 1,179 North American travelers who visited Mexico from 2005 to 2007. Travelers' diarrhea (TD) was reported by 521 (44%) participants. Among subjects with TD, 218 cases were examined for cryptosporidiosis by polymerase chain reaction (PCR) and enzyme-linked immunoassays (ELISA). There were 14 (6%) cases of cryptosporidiosis and 141 cases (64%) of bacterial diarrhea. Compared with bacterial diarrhea, a longer stay in Mexico was a risk factor for cryptosporidiosis. Additionally, Cryptosporidium cases passed greater number of watery stools (P < 0.05), suffered more episodes of diarrhea (P < or = 0.05), and were more likely to experience tenesmus (P < or = 0.05) compared with bacterial causes of TD. ELISA detected seven (3%) cases of Cryptosporidium, whereas PCR identified an additional seven cases (6%). Speciation by 18SrRNA sequencing showed that 13 cases were caused by C. parvum and only 1 case was caused by C. hominis. ELISA showed a sensitivity of 50% and specificity of 100% compared with PCR.

Environmental risk factors for Cryptosporidium infection in an island from Western Venezuela

Few investigations have been conducted on risk factors for Cryptosporidium infection in communities from developing countries. A study was conducted to determine the prevalence and risk factors for cryptosporidiosis in San Carlos island, Venezuela. A sample of 515 subjects (mean age +/- SD: 21.4 +/- 17.8 years) was surveyed. Single fecal specimens were collected and modified Ziehl-Neelsen carbolfuchsin staining of formalin-ether concentrate stools were examined for identification of the parasite. Infections with Cryptosporidium (67 of 515, 13%) were common. Prevalence of the parasite varied among sectors of the community; 34 of 67(50.7%) cases of cryptosporidiosis clustered in two sectors with extreme poverty. Variables strongly associated with a higher risk for the infection (p < 0.01) were residing in these sectors versus the remainder, living in a hut or small residence versus a brick or larger house, using an area of backyard rather than a toilet or latrine for defecation, and having contact with soil contaminated with human feces. Crowding was also a risk (p < 0.05). Contact with human feces contaminated-soil may be an important mode of transmission and poverty a predisposing factor for the infection.

Genotyping of Cryptosporidium spp. isolated from human stool samples in Switzerland.

In a study to estimate the frequency of Cryptosporidium infections in Switzerland, stool samples from patients found to be positive for Cryptosporidium spp. by modified Ziehl-Neelson staining and fluorescence microscopy were used for genotyping experiments. With 9 of 12 samples, DNA extraction and subsequent genotyping was successful. All Cryptosporidium-isolates belonged to the bovine genotype. In one stool sample, two strains of Cryptosporidium were demonstrated, suggesting a mixed infection. In comparison with reference strains from calves, one of the isolates showed a full sequence identity and the other a similarity of 97.5%. The fact that only bovine genotypes were detected suggests, that cryptosporidiosis must primarily be considered as a zoonotic disease in Switzerland. This is in contrast to other countries, where the human genotype of C. parvum was shown to dominate the epidemiological situation. The results of our study are supported by the previous finding, that two of the analysed strains originated from patients who used to consume raw milk or raw cream, a known risk factor for cryptosporidiosis.

Analysis of the spatial distribution of cryptosporidiosis in AIDS patients in San Francisco using density equalizing map projections (DEMP)

Environmental transmission of cryptosporidiosis has occurred repeatedly in defined spatial areas during outbreaks of disease attributed, for example, to drinking water contamination. Little work has been done to investigate the possibility of cryptosporidiosis infection in defined spatial areas in non-outbreak (i.e., endemic) settings. This study applies a novel approach to the investigation of the spatial distribution of cryptosporidiosis in AIDS patients in San Francisco. Density equalizing map projection (DEMP) maps were created for nine race/ethnicity-age groups of AIDS patients based on census tract of residence. Additionally, census tracts with a “high density” of cryptosporidiosis cases were identified by applying smoothing techniques to the DEMP maps, and included as a covariate in multivariate Poisson regression analyses of other known risk factors for cryptosporidiosis. These analyses suggest: (1) cases of cryptosporidiosis among Black and Hispanic AIDS patients, but not among Whites, show a statistically significant non-random spatial distribution (p<0.05) even after adjustment for the underlying spatial distribution of AIDS patients for these demographic groups, and (2) the risk of residence in these high density census tracts, adjusted for other known risk factors, was not statistically significant (relative risk=1.27, 95% confidence interval 0.15, 10.53). These results do not support an independent effect of spatial distribution on the transmission of cryptosporidiosis among AIDS patients.