Cryptosporidium Species Oocysts Research Articles

Incidence of Cryptosporidium: A Neglected Parasite in Immunocompetent Adults in Swabi

Objective: To highlight the increasing incidence of Cryptosporidium in immunocompetent adults and the resultant altered epidemiology. Methodology: This study was conducted over a period of one year, from 1st January 2023 to 1st of January, 2024 at Microbiology Laboratory MTI- GKMC/BKMC, Swabi. Modified Ziehl Neelsen staining was performed on the received stool samples from patients presenting with wide range of symptoms associated with Irritable Bowel Syndrome (IBS). Abdominal pain, recurrent episodes of diarrhea and weight loss were the main symptoms. Modified ZN stain being one of the most reliable, quick and cost effective methods for the detection of cysts of Cryptosporidium using 40X and oil immersion lens was used for diagnosis. Results: A total of 62 samples were received from immunocompetent patients in the said period out of which 34% were positive for the oocysts of Cryptosporidium species. Out of a total of 21 positive samples 62% were males and 38% were females. The age range of the patients spanned between 20 to 60 years. Conclusion: Knowing this high incidence 34% of Cryptosporidium spp. in the healthy adults, necessitates to prioritize steps for the prevention of this infection by implementation of public health measures.

Cryptosporidium spp. and Eimeria spp. (Apicomplexa: Eimeriorina) of freshwater Cyprinid fish species in the Kura River basin in Azerbaijan territory.

This study aims to determine the prevalence of Cryptosporidium and Eimeria spp. oocysts in fish specimens in the river Kura. It was conducted during the 2021-2022 at two sites: Mingachevir reservoir in central Azerbaijan and in Neftchala district where the river finally enters the Caspian Sea through a delta of the Kura River estuary. The diagnosis of oocysts was performed microscopically. Fine smears from the intestine epithelial layers stained by Ziehl-Neelsen for Cryptosporidium oocysts. To identify Eimeria oocysts, each fish's faecal material and intestinal scrapings were examined directly under a light microscope in wet samples on glass slides with a coverslip. Results revealed a prevalence of Cryptosporidium and Eimeria species infections in fish hosts from both territories Rutilus caspicus, Alburnus filippi, Abramis brama orientalis and Carassius gibelio. Of 170 investigated fish specimens, 8.8% (15/170) were infected with Cryptosporidium species oocysts. Eimeria species oocysts were identified in 20.6% (35/170). The presence of Cryptosporidium and Eimeria infections in fish specimens are natural infections. However, their presence in fish species may be attributed to the age of the fish species and water pollution. This is the first report regarding the prevalence of Cryptosporidium oocysts in fish species in Azerbaijan.

Nitazoxanide refractory cryptosporidiosis complicating Burkitt lymphoma in a child.

Cryptosporidium species cause watery diarrhea in several vertebrate hosts, including humans. Most apparently, immunocompetent-infected individuals remain asymptomatic, whereas immunocompromised may develop severe or chronic cryptosporidiosis. We report here the case of a 6-year-old girl undergoing chemotherapy for Burkitt lymphoma who experienced multiple episodes of watery diarrhea during her hospital stay. Microscopic examination of her stool sample revealed oocysts of Cryptosporidium species. The rapid immunochromatographic test was also positive for Cryptosporidium species. She was treated with nitazoxanide for 3 weeks, which failed to provide both clinical improvement and parasitological clearance. This case highlights the importance of treatment failure in human cryptosporidiosis.

Cryptosporidiosis and Associated Risk Factors among Children Attending Paediatric Hospitals in Enugu Metropolis, Enugu State, Nigeria

Cryptosporidiosis is a zoonotic disease caused by infection with protozoan parasite of the genus Cryptosporidium. It is associated with moderate to severe diarrhoea which may eventually lead to death. The parasite impedes growth and development of affected children. A hospital based cross-sectional study was conducted to assess cryptosporidiosis and the associated risk factors among children aged 0-15years attending selected paediatric hospitals in Enugu Metropolis between November 2021 and August 2022. A total of five hundred and fifty stool samples were examined for oocysts of Cryptosporidium species using Formol Ethyl-Acetate sedimentation and modified Ziehl Neelsen’s staining techniques. The overall prevalence of the parasite was 14.4% (79/550). Enugu State University of Science and Technology Teaching Hospital recorded the highest prevalence 32(25.6%) of Cryptosporidium species while St. Patrick Hospital recorded the least 1(1.1%). Public hospitals recorded more infections than private hospitals. The age group ≤ 5years 43(15.8%) recorded the highest prevalence. Males 52(17.1%) were more infected than females 27(10.98%), which was not significant (P>0.05). Children whose parents/caregivers had only primary education 11(26.8%), has the highest prevalence while those whose parents/caregivers had tertiary education 17(8.9%), has the least. Children whose parents/caregivers were farming has the highest prevalence 9(25.0%), while children of civil servants, 40(12.4%) has the least which was not significant (P>0.05). Children living in multifamily residences 48(15.2%) had higher prevalence than those living in private homes, 2(6.3%). Other protozoan parasites identified in the study were Entamoeba histolytica 88(16.1%) and Giardia lamblia 69(12.5%). There were co-infections of Cryptosporidium and Entamoeba histolytica 27(4.9%), Cryptosporidium and Giardia lamblia 21(4.3%) which was not significant (P>0.05). Intervention through health education on good hygiene habits, and provision of clean water and proper disposal of faeces will help reduce cryptosporidiosis among children.

Multiple protozoal infections in a single immunocompromised patient: A case report.

Immunocompromised patients with human immunodeficiency virus (HIV) infection are prone to multiple infections, of which parasitic infections are an important cause. Parasitic protozoal infections - both by common and rare protozoa are documented in such patients. Here, we report a rare and interesting case of five protozoal infections affecting a single HIV-infected person at the same time of initial presentation. A 64-years-male came to us with complaints of chronic diarrhea for 6 months. He was investigated and found to be positive for HIV I. His stool examination revealed cysts of Entameba histolytica and Giardia lamblia and oocysts of Cryptosporidium species and Cystoisospora species. His toxoplasma IgG was also positive in high titer. The patient was medically diagnosed and was treated with medications as clinically prescribed - antiretroviral therapy was initiated and he was discharged in due course. A total of five protozoal infections were documented affecting a single person - newly diagnosed immunocompromised male, which by sheer qualitative count of patient case histories, indeed is a rare case reported in the medical literature.

Chronicle of migrant hyperinfective Strongyloides stercolaris larvae and associated bacteremia in a patient suffering from Idiopathic Thrombocytopenic Purpura

Background: Strongyloidiasis is a neglected nematode infestation and can lead to hyperinfection syndrome. The onset of strongyloides hyper-infection syndrome is associated with a myriad of seemingly unrelated symptoms including diarrhoea, abdominal pain, urticaria, anaemia, sepsis and acute respiratory distress syndrome. Case report: A 65-year-old female patient presenting with chief complaints of nausea, vomiting, abdominal cramps, diarrhea, fever and cough and was admitted to a teaching hospital on 2nd May 2019. The patient was a diagnosed case of idiopathic thrombocytopenic purpura on Azathioprine (50mg, BD) and oral corticosteroid therapy (Prednisolone 60mg, OD) and was on treatment from the same hospital. The patient developed these symptoms after 23 days of immunosuppressive therapy. Patient was continued with previous medication along with supportive management after admission. Blood and urine sample was received in the department of Microbiology on 3rd May 2019 for culture and sensitivity testing. Urine sample was sterile after 24 hours of aerobic incubation. Escherichia coli grew in blood culture and the isolate was susceptible to gentamicin, amikacin and colistin. Stool sample was received on 6th of May 2019 for routine microscopy. With wet mount preparation of stool specimen, numerous larvae of Strongyloides stercoralis were seen. Modified Ziehl-Neelsen staining was performed and oocysts of Cryptosporidium species were also seen. Wet mount preparation of sputum sample was also performed in which few larvae of S. stercoralis were seen. Conclusion: As corticosteroid is the mainstay of treatment in idiopathic thrombocytopenic purpura an early diagnosis and prompt specific anti-parasitic therapy is required to eradicate these infections

Prevalence of Cryptosporidium species oocysts among small ruminants in Potiskum livestock market, Yobe State, Nigeria

A cross-sectional study was carried out to determine the prevalence of Cryptosporidium species oocysts in small ruminants in Potiskum livestock market, Yobe State, Nigeria. Faecal samples from 203 animals; 100 sheep and 103 goats were tested using modified Ziehl-Neelsen staining technique. An overall prevalence of 20.7% (42/203) was recorded in the study with a higher prevalence of 21.4% (22/103) in goats than in sheep 20% (20/100); although the difference was not significant (p>0.05). In goats, the rate of Cryptosporidium species oocyst was higher in male (27.8%) than in female (22.4%), in young (30.6%) than in adults (22.4%), in those with loose/watery faeces (45.5%) than those with well-formed faeces (22.8%) but the differences were not significant (p>0.05). In sheep, the rate of infection was higher in female (16.9%) than in male (13.0%), in young ((19.2%) than in adults (14.9%) but the differences were not significant (p>0.05). The prevalence was significantly (p = 0.010) higher in sheep with loose/watery faeces (45.5%) than in those with well-formed faeces (12.4%). Breed of sheep did not significantly (p > 0.05) influence the prevalence rates, although the Uda breed had higher prevalence (25%) than the Balami (14.3%) and Yankasa (12.7%) breeds. A similar trend was observed for the sahelian breed of goats (35.7%) compared to the Red sokoto (23.7%), West African dwarf (16.7%) and mixed breeds (10.0%) (p = 0.367). Animals brought to the livestock market from Ngalda town showed highest prevalence of 36.4% than those from the other areas with prevalence rates of (0 to 33.3%). The finding of Cryptosporidium species oocysts in 20.7% of small ruminants in this study underscores the role of this zoonotic parasite diseases in animals and man and loose/watery faeces is a significant factor in the spread among small ruminants.

Cryptosporidium parvum decay during air drying and stockpiling of mesophilic anaerobically digested sewage sludge in a simulation experiment and oocyst counts in sludge collected from operational treatment lagoons in Victoria, Australia

The inactivation of Cryptosporidium species oocysts during sewage sludge treatment is important to protect human health when the residual biosolids are applied to agricultural land. Quantifying the decay of Cryptosporidium species during sludge treatment for microbiological assurance purposes is difficult if low numbers are present in wastewater. The rate of decay of Cryptosporidium parvum oocysts during solar/air drying treatment and in sludge stockpiles in temperate environment conditions was simulated in laboratory inoculation experiments using sludge sampled from a mesophilic anaerobic digester. Oocyst numbers were also determined in settled lagoon sludge samples collected from three operational rural wastewater treatment plants (WWTPs). C. parvum oocysts were enumerated by immunomagnetic separation followed by staining with vital dyes and examination by confocal laser scanning microscopy. An air-drying/storage period equivalent to 11 weeks was required for a 1 log10 reduction of viable oocysts inoculated into digested sludge. Oocyst viability in air-dried and stored digested sludge decreased with time, but was independent of sludge desiccation and dry solids (DS) content. No oocysts were detected in sludge samples collected from the anaerobic digester, and the average concentration of oocysts found in settled lagoon sludge from the rural WWTP was 4.6 × 102 oocysts/g DS.

DISTRIBUTION OF CRYPTOSPORIDIUM SPP INFECTION IN WILD PIGEONS IN BAGHDAD CITY -IRAQ

This study revealed the prevalence of Cryptosporidium parasite by using 120 fecal sample from wild pigeons in Baghdad city during the period Jounuary2013 to December 2013. The total infection rate was 40% [48/120] which divided in to 38.18% [21/55]in males and 41.53%[27/65] in females. A high infection rate 76.66% [23/30] was recorded in winter season, while a low infection rate 16.66%[5/30] was found in Autumn. The three Cryptosporidium species oocysts were detected varied from small (Cryptosporidium meleagridis ) , medium ( Cryptosporidium baileyi ) and large size( Cryptosporidium galli ).

Comparison between ELISA and various stains techniques in laboratory diagnosis of cryptosporidiosis.

Cryptosporidium spp. is an important parasitic protozoa causing diarrhea which is a severe life-threatening diarrhea especially in immunocompromised hosts. We aimed to evaluate the usefulness of detection of Cryptosporidium spp. copro-antigen from fecal specimens by using enzyme linked immunosorbent assay (ELISA) test and comparing its sensitivity and specificity with some staining methods. The results revealed that Modified Acid-Fast stain is considered better than Giemsa in detecting Cryptosporidium species oocysts in faecal smears as their sensitivity were 67.5% and 53.75% respectively. On contrary, ELISA technique is considered the best method used for detection of cryptosporidial infection as its sensitivity is 90%.

Detection of Cryptosporidium and Giardia in clinical laboratories in Europe—a comparative study

To determine the routine diagnostic methods used and compare the performance in detection of oocysts of Cryptosporidium species and cysts of Giardia intestinalis in faecal samples by European specialist parasitology laboratories and European clinical laboratories. Two sets of seven formalin-preserved faecal samples, one containing cysts of Giardia intestinalis and the other, containing oocysts of Cryptosporidium, were sent to 18 laboratories. Participants were asked to examine the specimens using their routine protocol for detecting these parasites and state the method(s) used. Eighteen laboratories answered the questionnaire. For detection of Giardia, 16 of them used sedimentation/concentration followed by light microscopy. Using this technique the lower limit of detection of Giardia was 17.2 cysts/mL of faeces in the best performing laboratories. Only three of 16 laboratories used fluorescent-conjugated antibody-based microscopy. For detection of Cryptosporidium acid-fast staining was used by 14 of the 17 laboratories that examined the samples. With this technique the lower limit of detection was 976 oocysts/mL of faeces. Fluorescent-conjugated antibody-based microscopy was used by only five of the 17 laboratories. There was variation in the lower limit of detection of cysts of Giardia and oocysts of Cryptosporidium between laboratories using the same basic microscopic methods. Fluorescent-conjugated antibody-based microscopy was not superior to light microscopy under the conditions of this study. There is a need for a larger-scale multi-site comparison of the methods used for the diagnosis of these parasites and the development of a Europe-wide laboratory protocol based upon its findings.

Occurrence of Cryptosporidium species in catfish (Clarias gariepinus) Harvested from two lakes and artificial ponds in Zaria, Northern Nigeria

Objective: To determine the occurrence of Cryptosporidium species in catfish (Clarias gariepinus) harvested from two lakes and ponds in Zaria, Kaduna State, Nigeria. Methods: Catfish samples (n=200) from two lakes and (n=200) from two private fish ponds were collected and their gills and gastrointestinal tract samples were analysed for Cryptosporidium oocysts using modified Ziehl-Neelsen staining technique was used, followed by microscopy. Results: Oocysts of Cryptosporidium species were found in all the sampling sites with an overall positivity rate of 49.75%. A comparison between the lakes and ponds as sampling sites revealed a statistically significant (P<0.05) higher percentage of occurrence of Cryptosporidium oocyst from the lakes (39.25%) than from the ponds (10.50%). Conclusions: These findings document for the first time the natural occurrence of Cryptosporidium sp. in catfish intended for human consumption and therefore, underlines the need for public enlightenment to guard against any possible zoonotic transmission.

Prevalence of faecal-borne parasites in colony stray cats in northern Italy.

Endoparasitic infections are common in stray cats. Many of these parasites are responsible for zoonoses, and stray cats can be a source of environmental contamination. The prevalence of parasites in 139 stray colony cats in the city of Milan, northern Italy, was investigated by faecal examination. The overall prevalence of endoparasites was 50.4%, with 11 different parasites found. Parasites with zoonotic potential were detected in 49.6% of cats. Concurrent infections with two or more zoonotic parasites were recorded in 14.3% of cats. Among the parasites found, the most common was Toxocara cati (33.1%; P <0.0001). The other species found by coproscopic examination were: Ancylostoma tubaeformae (7.2%), Isospora species (4.3%), Trichuris vulpis (2.9%), Dipylidium caninum (2.9%), Aelurostrongylus abstrusus (2.9%), Eucoleus aerophilus (syn Capillaria aerophila) (1.4%), Spirometra species (1.4%), Taenia pisiformis (0.7%) and Hymenolepis nana (0.7%). Coproantigen specific for Giardia duodenalis was detected in 2.9% of the samples. Pseudoparasites (eggs of mites) were found in 4.3% of the samples. No sample contained Toxoplasma gondii oocysts, despite the fact that 70 cats tested positive for T gondii-specific IgG antibodies, and none of the diarrhoetic samples tested positive for Cryptosporidium species oocysts. Variables linked to infection were body condition score (BCS), the presence of diarrhoea and infection with G duodenalis. Cats infected with G duodenalis were more likely to have a low BCS (odds ratio (OR) = 11.5, P = 0.02) and diarrhoea (OR = 30.7, P = 0.0007). The results of the present study confirm that endoparasitic infections, most of which have zoonotic potential, are distributed in stray colony cats of Milan.

Prevalence of gastrointestinal parasites and Cryptosporidium species in extensively managed pigs in Mekelle and urban areas of southern zone of Tigray region, Northern Ethiopia

Aim: The objective of this study was to investigate prevalence of gastrointestinal parasites and Cryptosporidium species in extensively managed pigs in Mekelle and urban areas of southern zone of Tigray Region, Ethiopia during June - September, 2012. Material and methods: Seven hundred fourteen pigs of different ages and sexes were selected for fecal sample collection. Fecal samples were collected from the rectum of pigs with strict sanitation. A total of 25 soil samples were also collected from backyards of pig pens using clean zipped plastic bags. Both fecal and soil samples were examined for eggs and cysts of GIT parasites by flotation and sedimentation techniques. Modified Ziehl – Neelsen technique was used to examine oocysts of Cryptosporidium species from 276 randomly selected fecal samples. Results: Out of 714 pigs examined through flotation and sedimentation, 27.3% were infected by at least one gastrointestinal parasite. Ascaris suum (25.9%) was the most prevalent parasite followed by Fasciola hepatica (1.8%), Eimeria spp. (1.7%) and Trichuris suis (0.3%). There was no significant association between sex and prevalence of parasites ÷2[df 1] = 1.921; P=0.166). Contrary to this, age of pigs had effect on prevalence of parasites ÷2[df 2] = 8.376; P=0.015). About 7% of pigs examined were positive for oocysts of Cryptosporidium spp. Moreover, 72% of the soil samples found to be contaminated with eggs of Ascaris spp. in the study area. Apart from causing morbidity in the infected pigs, the potential of Ascaris of pigs to infect man and vice versa together with poor environmental hygiene, may complicate the epidemiology and control of Ascariasis in the study areas. Extensively managed pigs may also act as potential reservoirs for zoonoses of Cryptosporidium species. Conclusion: It is concluded that further investigations are crucial on molecular characterization of Ascaris and Cryptosporidium isolates of extensively managed pigs to determine the parasites upto species level so as to suggest proper control strategies.

Prevalence of intestinal parasites in relation to CD4 counts and anaemia among HIV-infected patients in Benin City, Edo State, Nigeria

Parasitic infections continue to take their toll on HIV positive patients by influencing the blood qualitatively and quantitatively. The objective of this study was to determine the prevalence of intestinal parasitic infections in relation to anaemia and CD4 counts among HIV-infected patients in Benin City, Nigeria. Using a serial sampling method, a total of 2000 HIV-infected patients were recruited on their first visit prior to highly active anti-retroviral therapy (HAART) at the University of Benin Teaching Hospital from August 2007 to August 2009. Stool and blood samples were collected from each patient. The stool samples were processed using the modified Ziehl-Neelsen staining technique to microscopically identify the oocysts of Cryptosporidium species, Isospora belli, Cyclospora species and spores of Microsporidium species while saline and iodine preparations were used for identifying the ova, cysts and parasites of Ascaris lumbricoides, hookworm, Taenia spp and other parasites. The blood specimens were equally analyzed using the flow cytometry for CD4+ T-lymphocyte count and autoanalyzer - sysmex kx - 21 for haemoglobin concentration. The overall prevalence of anaemia was 93.3% while 18% had parasitic infections. There was a significant relationship between CD4 count <200cells/microL and anaemia (P<0.0001). Cryptosporidium species (P= 0.005), A. lumbricoides (P=0.035), hookworm and Taenia species (P=0.014) were associated with anaemia. Anaemia was associated with CD4 count while Cryptosporidium species, Ascaris lumbricoides, hookworm and Taenia species were the intestinal parasitic agents associated with anaemia. In conclusion the prevalence of anaemia in HIV-infected patients is high low CD4 count is a significant risk factor of acquiring anaemia. Except for isosporiasis, cryptosporidiosis, A. lumbricoides, hookworm and Taenia species in HIV infected individuals are parasitic agents associated with anaemia. Routine screening for intestinal parasites and holistic management of anaemia is advocated.

Cryptosporidium Recovered from Musca domestica, Musca sorbens and Mango Juice Accessed by Synanthropic Flies in Bahirdar, Ethiopia

The study was conducted to determine the role of house flies, Musca domestica and Musca sorbens to carry Cryptosporidium species in natural environment and filth flies potential for contamination of food item they visited using acid-fast stain technique. Cryptosporidium was identified from flies collected in dairy cow barns, butchery, market and defecating grounds. Musca domestica captured from dairy cow barns and M. sorbens from defecating ground were found carrying more oocyst of Cryptosporidium parvum. Oocyst load per fly for M. domestica and M. sorbens was 5.84 and 3.42, respectively. Flies' population dynamics in each month had little relation to the monthly oocyst frequency, r = 0.06 and 0.02 for M. domestica and M. sorbens, respectively. Cryptosporidium species oocysts were isolated from frozen mango juice, which filth flies visited in dairy farm barn. Load of oocysts in the mango juice was dependent on time contact of flies with mango juice and more oocysts were recovered (P < 0.05) in mango juice samples accessed by filth flies for longer period. Role of filth flies to carry and deposit Cryptosporidium species oocyst for development of food-borne cryptosporidiosis is signified.

Prevalence of Cryptosporidium, Giardia and Isospora species infections in pet cats with clinical signs of gastrointestinal disease

This study reports the prevalence of Cryptosporidium, Giardia and Isospora species in cats showing signs of gastrointestinal disease. Records from a United Kingdom commercial diagnostic laboratory between December 2003 and December 2005 were reviewed. Of 1355 cats, Cryptosporidium species oocysts were found in 13 cats (1%), Giardia species trophozoites in 74 (6%), and Isospora felis oocysts in 46 (3%). In a second group of 48 cats, prevalence of Giardia species was 15% using an immunoassay for detection of antigen compared to 4% detected with microscopy. Prevalence of Giardia (9%) and Isospora (9%) species was higher in cats less than 6 months old. Gender and breed did not affect prevalence. There was a trend for Cryptosporidium and Isospora species infections to be detected in late autumn and early winter. Regional differences in prevalence were not detected. None of these organisms show a characteristic pattern of clinical signs. This study demonstrates that enteric protozoal infection is common in domestic cats showing signs of alimentary disease.

Occurrence of &lt;italic&gt;Cryptosporidium&lt;/italic&gt; species in surface water in South-eastern Nigeria: The public health implication

Using filtration, backwashing, concentration and modified Ziehl-Neelsen staining technique techniques water samples from major rivers serving for drinking and irrigation purposes were analyzed for Cryptosporidium oocysts in South-eastern Nigeria. Oocysts of Cryptosporidium species were found in all the sampling sites and there was significant variations` in the concentration of oocysts (F-ratio=3.367, P<0.05) with the highest mean oocyst concentration of 183.3 per litre of water while the least mean oocyst concentration of 120.6 per litre of water recorded. The highest mean monthly oocysts concentration of 226.5 per litre of water was observed in March while the least mean monthly oocysts concentration of 83.7 per litre of water was observed in the month of April. The differences in the mean monthly oocysts concentration per litre of water was statistically significant (F-ratio=3.23, P<0.05). As a public health measure, the development of public policies that limit contamination of surface waters is recommended.

Prevalence of cryptosporidian infection in cats in Turin and analysis of risk factors

An epidemiological study was carried out to identify factors associated with the risk of cryptosporidian infection in cats. Faecal samples from 200 domestic cats were collected in the small animal clinic at the Faculty of Veterinary Medicine in Turin (north-west Italy). The faecal samples were analysed for the presence of Cryptosporidium species oocysts using a centrifugation concentration floatation method. For each cat, age, sex, breed, indoor/outdoor status, diet, diarrhoea and presence of other enteric parasites were analysed for association with Cryptosporidium species infection. Cryptosporidia oocysts were identified in 49 cats (24.5%) aged from 2 months to 18 years. Statistical analysis revealed that four variables are significantly associated with an increased risk of infection: less than 1 year of age (chi(2)=6.5, P=0.01), feeding home-cooked diet (chi(2)=6.92, P<0.01), presence of diarrhoea (chi(2)=4.34, P<0.037), and presence of other enteric parasites (chi(2)=10.31, P<0.01). No statistical differences were found for sex (chi(2)=1.56, P=0.21), breed (chi(2)=0.78, P=0.38) and outdoor/indoor status (chi(2)=1.49, P=0.22). Cryptosporidium species was the parasite most frequently detected in the cats surveyed.

Infectivity of a Cryptosporidium species isolated from a domestic cat ( Felis domestica) in lambs and mice

Two neonatal lambs were inoculated orally with purified Cryptosporidium species oocysts isolated from a farm cat. Oocysts first appeared in the faeces of the two lambs three and 10 days after infection. Two distinct sizes of oocysts were observed in the faeces of both the cat and the lambs, the smaller measuring approximately 5·0 × 4·5 μm and the larger measuring approximately 6·0 × 5·0 μm in diameter. The smaller type predominated. Histological examination of the alimentary tract of the lambs revealed endogenous stages of Cryptosporidium in the epithelial borders of the ileum. In addition, Cryptosporidium oocysts were detected in impression smears from the jejunum, ileum, caecum and colon. Suspensions of 10 3 oocysts from the faeces of the farm cat were inoculated into each of 10 newborn mice and 10 4 oocysts from the two experimentally infected lambs were inoculated into each of 20 newborn mice. Cryptosporidium oocysts were detected in gut homogenates from 19 of the 20 mice inoculated with oocysts from the lambs but in none of the mice inoculated with oocysts from the cat.