High prevalence and seasonality of cryptosporidiosis in a small rural village occupied predominantly by aged people in the Republic of Korea

PREVALENCE OF CRYPTOSPORIDIUM SPP. AMONG ASYMPTOMATIC HEALTHY EXPATRIATE WORKERS IN SHARJAH, UNITED ARAB EMIRATES

Background:

Epidemiological data on Cryptosporidium infections in the United Arab Emirates (UAE) is scarce. Therefore, the main objective of this study was to determine the prevalence of Cryptosporidium species among a community of expatriates in Sharjah, UAE working in different sectors, including the food industry, house maids and other domestic occupations.

Materials and Methods:

One hundred and thirty four stool samples were collected from asymptomatic individuals presenting to the Sharjah Municipality Public Health Clinic (SMPHC) for screening of intestinal parasites for work permission purposes between 2009 and 2011. Demographic information such as age, sex, and country of origin was collected. Genomic DNA extracted from the stool samples were tested for Cryptosporidium species using real-time PCR (qPCR).

Results:

Twenty-six individuals (19.4%) were positive for Cryptosporidium sp. by PCR. The infection rate was found to be highest in Afghan nationals (33%; 3/9) compared with the rest of the study population; yet, no significant association existed between nationality and infection rate. Moreover, no association was observed between infection rate and gender (χ² = 2.439; P = 0.118), nor infection rate and age group (χ² = 1.219; P = 0.544).

Conclusion:

Infection by Cryptosporidium sp. was common in the study group, and further studies are needed within the native Emirati population before any conclusions can be made about foreigners potentially transmitting the parasite. Furthermore, data provided in this study could help determine its public and veterinary significance particularly in outbreaks in the country.

Multilocus typing of Cryptosporidium spp. in young calves with diarrhea in Korea

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Cryptosporidium spp. were detected using PCR and ELISA in diarrheal feces from calves.

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PCR and ELISA data showed good agreement in detecting C. parvum.

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Multilocus typing with 18S rRNA, gp60, and hsp70 genes of C. parvum was performed.

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Subtyping of C. parvum gp60 gene first revealed IIaA18G3R1 and IIaA16G3R1 in Asia.

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PCR and sequencing of hsp70 gene clearly differentiated C. bovis and C. ryanae.

We assessed the prevalence and performed molecular analysis of Cryptosporidium spp. in diarrheal feces of calves in Korea. Diarrheal fecal samples were collected from 951 young calves (<3 months) on 425 farms. Cryptosporidium prevalence was assessed by PCR and ELISA, and molecular characterization was performed by targeting the 18S rRNA, heat-shock protein 70 (hsp70), and glycoprotein 60 (gp60) genes. Data were analyzed according to the sex, type of cattle, region, season, and type of diarrhea. PCR analysis revealed Cryptosporidium spp. in 9.9% (94/951) of diarrheal fecal samples. C. parvum and C. bovis/ryanae were present in 6.1% (58/951) and 4.1% (39/951) of diarrheal fecal samples, respectively. In addition, ELISA showed positive results for C. parvum in 9.7% (92/951) samples. Statistical analysis of the PCR and ELISA results revealed a lower prevalence of C. parvum in the hemorrhagic diarrheal samples (P < 0.05). For C. bovis/ryanae, seasonality and high prevalence in hemorrhagic diarrhea were observed (P < 0.05). Of the 951 samples tested for C. parvum, 903 samples showed agreement with a κ value of 0.65, indicating good agreement between the two tests. Although C. bovis and C. ryanae share highly similar 18S rRNA sequences, PCR based on hsp70 successfully distinguished C. bovis from C. ryanae. Sequence analysis of gp60 revealed that C. parvum belonged to the IIa families and was further subtyped as IIaA18G3R1 and IIaA16G3R1, which have not been previously reported in Asia. These findings indicate that Cryptosporidium spp. play an important role in diarrhea in young calves in Korea. Considering the zoonotic significance of C. parvum IIa subtype and dense rearing system of cattle in Korea, prevention and continuous monitoring of Cryptosporidium are required.

Untangling the Impacts of Climate Change on Waterborne Diseases: a Systematic Review of Relationships between Diarrheal Diseases and Temperature, Rainfall, Flooding, and Drought

Global climate change is expected to affect waterborne enteric diseases, yet to date there has been no comprehensive, systematic review of the epidemiological literature examining the relationship between meteorological conditions and diarrheal diseases. We searched PubMed, Embase, Web of Science, and the Cochrane Collection for studies describing the relationship between diarrheal diseases and four meteorological conditions that are expected to increase with climate change: ambient temperature, heavy rainfall, drought, and flooding. We synthesized key areas of agreement and evaluated the biological plausibility of these findings, drawing from a diverse, multidisciplinary evidence base. We identified 141 articles that met our inclusion criteria. Key areas of agreement include a positive association between ambient temperature and diarrheal diseases, with the exception of viral diarrhea and an increase in diarrheal disease following heavy rainfall and flooding events. Insufficient evidence was available to evaluate the effects of drought on diarrhea. There is evidence to support the biological plausibility of these associations, but publication bias is an ongoing concern. Future research evaluating whether interventions, such as improved water and sanitation access, modify risk would further our understanding of the potential impacts of climate change on diarrheal diseases and aid in the prioritization of adaptation measures.

Prevalence of Cryptosporidium Infection among Inhabitants of 2 Rural Areas in White Nile State, Sudan

Cryptosporidium , a protozoan parasite that causes watery diarrhea, is found worldwide and is common in areas with low water hygiene. In February 2014, 866 stool samples were collected from the inhabitants of 2 rural areas in White Nile State, Sudan. These stool samples were assessed by performing modified acid-fast staining, followed by examination under a light microscope. The overall positive rate of Cryptosporidium oocysts was 13.3%. Cryptosporidium oocysts were detected in 8.6% stool samples obtained from inhabitants living in the area having water purification systems and in 14.6% stool samples obtained from inhabitants living in the area not having water purification systems. No significant difference was observed in the prevalence of Cryptosporidium infection between men and women (14.7% and 14.1%, respectively). The positive rate of oocysts by age was the highest among inhabitants in their 60s (40.0%). These findings suggest that the use of water purification systems is important for preventing Cryptosporidium infection among inhabitants of these rural areas in Sudan.

A waterborne outbreak and detection of cryptosporidium oocysts in drinking water of an older high-rise apartment complex in seoul

From May to June 2012, a waterborne outbreak of 124 cases of cryptosporidiosis occurred in the plumbing systems of an older high-rise apartment complex in Seoul, Republic of Korea. The residents of this apartment complex had symptoms of watery diarrhea and vomiting. Tap water samples in the apartment complex and its adjacent buildings were collected and tested for 57 parameters under the Korean Drinking Water Standards and for additional 11 microbiological parameters. The microbiological parameters included total colony counts, Clostridium perfringens, Enterococcus, fecal streptococcus, Salmonella, Shigella, Pseudomonas aeruginosa, Cryptosporidium oocysts, Giardia cysts, total culturable viruses, and Norovirus. While the tap water samples of the adjacent buildings complied with the Korean Drinking Water Standards for all parameters, fecal bacteria and Cryptosporidium oocysts were detected in the tap water samples of the outbreak apartment complex. It turned out that the agent of the disease was Cryptosporidium parvum. The drinking water was polluted with sewage from a septic tank in the apartment complex. To remove C. parvum oocysts, we conducted physical processes of cleaning the water storage tanks, flushing the indoor pipes, and replacing old pipes with new ones. Finally we restored the clean drinking water to the apartment complex after identification of no oocysts.

Prevalence and risk factors for intestinal protozoa infection in elderly residents at Long Term Residency Institutions in Southeastern Brazil

This study determined the prevalence of intestinal protozoa in Long Term Residency Institutions for the Elderly (ILPI) in elders, nurses and food handlers, identifying the risk factors associated with the infections. Stool samples taken from the elderly (n = 293), nurses (63) and food handlers (19) were studied. Questionnaires were used with questions related to sociodemographic variables, health, behavior and health characteristics. Stool samples were examined using the techniques of Faust and Ziehl Neelsen, and the prevalence of G. duodenalis, Cryptosporidium spp., E. histolytica/dispar in the elderly was 4.0%, 1.0% and 0.3% respectively. Nurses and food handlers showed 4.8% and 5.2% positivity only for G. duodenalis, respectively. The origin of the individuals and contact with domestic animals has been associated with infection by G. duodenalis in the elderly, and contact with domestic animals was considered a risk factor for infection. The last stool examinations were related to Cryptosporidium spp.. None of the variables were associated with E. histolytica/dispar. The frequency of hand washing was significantly associated with G. duodenalis among nurses. The frequency of positive samples of G. duodenalis, Cryptosporidium spp., E. histolytica/dispar showed that ILPIs environments are conducive to this occurring due to contact between the elderly, nurses and food handlers, which are often poorly trained in hygiene procedures and food handling.

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.

A survey of Cryptosporidium oocysts in water supplies during a 10-year period (2000-2009) in Seoul

This study has been conducted to estimate the occurrence of Cryptosporidium oocysts in water supplies in the Metropolitan area of Seoul, South Korea, for 10 years from 2000 to 2009. Water samples were collected quarterly at 6 intakes in the Han River and its largest stream and 6 conventional Water Treatment Plants (WTPs) serving drinking water for 10 million people of Seoul. Cryptosporidium oocysts were found in 22.5% of intake water samples and arithmetic mean was 0.65 oocysts/10 L (range 0-22 oocysts/10 L). Although the annual mean of oocyst number was as low as 0.04-1.90 oocysts/10 L, 3 peaks in 2004 and 2007 were observed and the pollution level was a little higher in winter. The lowest density was observed at Paldang intake and the pollution level increased at Kuui and Jayang intakes. At the end of the largest stream, oocysts were found in 70% of collected samples (mean 5.71 oocysts/10 L) and it seemed that its joining the Han River resulted in the increase at Kuui intake and downstream. Oocyst removal by physical process exceeded 2.0-2.3 log and then all finished water samples collected at 6 WTPs were negative for Cryptosporidium in each 100 L sample for 10 years. These results suggested that domestic wastewater from the urban region could be a source of Cryptosporidium pollution and separating sewage systems adjacent to the intakes could be meaningful for some intakes having weakness related to parasitological water quality.

Multisite study of cryptosporidiosis in children with diarrhea in India

Cryptosporidium spp., a common cause of diarrhea in children, were investigated in the first multisite study in India. Diarrheal stools from hospitalized children aged <5 years from Delhi, Trichy, and Vellore were analyzed by microscopy, PCR-restriction fragment length polymorphism (RFLP), and/or sequencing at the small-subunit (SSU) rRNA and Cpgp40/15 loci for species determination and subgenotyping, respectively. Seventy of 2,579 (2.7%) children, 75% of whom were <2 years old, had cryptosporidial diarrhea as determined by microscopy. Genotyping and subgenotyping showed that Cryptosporidium hominis was the most commonly identified species (59/67 children), and subgenotypes Ie, Ia, Ib, and Id were common in all centers. A novel C. parvum subgenotype, IIn, was identified in Vellore. Meteorological analysis revealed a higher rate of cryptosporidial positivity during hotter and drier weather in Delhi.

Review of zoonotic parasites in medical and veterinary fields in the Republic of Korea

Zoonotic parasites are animal parasites that can infect humans. The major zoonotic protozoa in the Republic of Korea are Babesia bovis, Chilomastix mesnili, Cryptosporidium parvum, Endolimax nana, Entamoeba coli, Entamoeba hitolytica, Giardia lamblia, Iodamoeba bütschlii, Pneumocystis carinii, Sarcocystis cruzi, and Toxoplasma gondii. The major zoonotic helminths in Korea include trematodes, cestodes, and nematodes. Trematodes are Clonorchis sinensis, Echinostoma hortense, Echinostoma spp., Fasciola hepatica, Heterophyes nocens, Metagonimus yokogawai, and Paragonimus westermani. Cestodes are Diphyllobothrium latum, Dipylidium caninum, Echinococcus granulosus, Hymenolepis nana, Raillietina tetragona, sparganum (Spirometra spp.), Taenia saginata, T. solium, and T. asiatica. Nematodes are Ancylostoma caninum, Brugia malayi, Capillaria hepatica, Dirofilaria immitis, Gnathostoma dololesi, Gnathostoma spinigerum, Loa loa, Onchocerca gibsoni, Strongyloides stercoralis, Thelazia callipaeda, Trichinella spiralis, Trichostrongylus orientalis, Trichuris trichiura, and Trichuris vulpis. The one arthropod is Sarcoptes scabiei. Many of these parasites have disappeared or were in decline after the 1990's. Since the late 1990's, the important zoonotic protozoa have been C. parvum, E. nana, E. coli, E. hitolytica, G. lamblia, I. buetschlii, P. carinii and T. gondii. The important zoonotic helminths have been C. sinensis, H. nocens, M. yokogawai, P. westermani, D. latum, T. asiatica, sparganum, B. malayi, T. orientalis, T. callipaeda and T. spiralis. However, outbreaks of these parasites are only in a few endemic areas. The outbreaks of Enterobius vermicularis and head lice, human parasites, have recently increased in the kindergartens and primary schools in the Republic of Korea.

Seasonality of cryptosporidiosis: A meta-analysis approach

OBJECTIVES

We developed methodology for and conducted a meta-analysis to examine how seasonal patterns of cryptosporidiosis, a primarily waterborne diarrheal illness, relate to precipitation and temperature fluctuations worldwide.

METHODS

Monthly cryptosporidiosis data were abstracted from 61 published epidemiological studies that cover various climate regions based on the Köppen Climate Classification. Outcome data were supplemented with monthly aggregated ambient temperature and precipitation for each study location. We applied a linear mixed-effect model to relate the monthly normalized cryptosporidiosis incidence with normalized location-specific temperature and precipitation data. We also conducted a sub-analysis of associations between the Normalized Difference Vegetation Index (NDVI), a remote sensing measure for the combined effect of temperature and precipitation on vegetation, and cryptosporidiosis in Sub-Saharan Africa.

RESULTS

Overall, and after adjusting for distance from the equator, increases in temperature and precipitation predict an increase in cryptosporidiosis; the strengths of relationship vary by climate subcategory. In moist tropical locations, precipitation is a strong seasonal driver for cryptosporidiosis whereas temperature is in mid-latitude and temperate climates. When assessing lagged relationships, temperature and precipitation remain strong predictors. In Sub-Saharan Africa, after adjusting for distance from the equator, low NDVI values are predictive of an increase in cryptosporidiosis in the following month.

DISCUSSION

In this study we propose novel methodology to assess relationships between disease outcomes and meteorological data on a global scale. Our findings demonstrate that while climatic conditions typically define a pathogen habitat area, meteorological factors affect timing and intensity of seasonal outbreaks. Therefore, meteorological forecasts can be utilized to develop focused prevention programs for waterborne cryptosporidiosis.

Prevalence and molecular characterization of bovine Cryptosporidium isolates in India

A survey based on PCR assay of 18S SSU rRNA gene revealed a 30.2% infection with Cryptosporidium spp., out of 457 faecal samples collected from neonatal bovine calves across three different regions of India. The PCR-RFLP pattern of the gene in all the positive cases established the species as Cryptosporidium parvum. Highest prevalence was recorded in the monsoon months (37.3%) and in the calves showing acute diarrhoea (32.3%). The calves below 15 days of age were mostly affected (45.1%). The infection was more prevalent in the northern parts (35.4%) of the country than in the eastern or southern parts. Results indicated that C. parvum was the only species of Cryptosporidium prevalent in bovine calves in three different geographical regions of India.

A survey of cryptosporidiosis among 2,541 residents of 25 coastal islands in Jeollanam-Do (Province), Republic of Korea

In order to determine the distribution and prevalence of human cryptosporidiosis on western and southern coastal islands of Jeollanam-do (Province), fecal samples were collected from 2,541 people residing on 25 islands, 13 in the western coasts and 12 in the southern coasts, during July and August 2000. Fecal smears were prepared following formalin-ether sedimentation of the samples and stained by a modified acid-fast procedure. The presence of Cryptosporidium oocysts was determined by light microscopy. Cryptosporidium oocysts were detected in 38 specimens (1.5%). The oocyst positive rate varied (0-6.0%) according to island; the highest was detected on Oenarodo (6.0%), followed by Naenarodo (5.6%) and Nakwoldo (5.4%). The majority (35 persons, 94.6%) of Cryptosporidium-infected individuals were older than 50 years of age. Men (22/1,159; 1.9%) were infected at a higher rate than women (16/1,382; 1.2%). The results of the present survey indicate that human Cryptosporidium infections (due to Cryptosporidium hominis and/or C. parvum) are maintained at a relatively low prevalence on coastal islands of Jeollanam-do, Republic of Korea.

Observations on the epidemiology of bovine cryptosporidiosis in India

The significance of Cryptosporidium as a causative agent of diarrhea has been assessed in bovine for a period of 2 years. A total of 940 faecal samples (470 samples in each year) both from diarrhoeic and non-diarrhoeic bovine (0-12 months age) were examined during three different seasons (rainy season, summer and winter). Overall Cryptosporidium was detected in 17.46% and 18.04% cases in first and second year, respectively. Out of 50.21% diarrhoeic and 49.79% non-diarrhoeic cases Cryptosporidium was detected in 26.79% and 8.13% in first year and 27.49% and 8.59% in second year. Year did not have any significant effect on the occurrence of cryptosporidiosis in bovine during this study period. The prevalence of cryptosporidiosis, both in diarrhoeic (61.64%) and non-diarrhoeic (47.22%) cases was highest in 0-1-month age group (P<0.01). Such a high percentage of cryptosporidiosis in clinically asymptomatic animals indicated that the particular age group of animals might be reservoir for the parasite. During this study period highest prevalence was recorded in rainy season (27.55%) followed by summer (16.99%) and winter (8.71%) (P<0.01). A total of 166 positive cases were genotyped. Molecular characterization of bovine cryptosporidiosis has been carried out by PCR-RFLP analysis of SSU rRNA gene and results indicated that Cryptosporidium parvum mainly responsible for diarrhea in bovine in India.

Genotype analysis of Cryptosporidium spp. prevalent in a rural village in Hwasun-gun, Republic of Korea

Two species of Cryptosporidium are known to infect man; C. hominis which shows anthroponotic transmission between humans, and C. parvum which shows zoonotic transmission between animals or between animals and man. In this study, we focused on identifying genotypes of Cryptosporidium prevalent among inhabitants and domestic animals (cattle and goats), to elucidate transmittal routes in a known endemic area in Hwasun-gun, Jeollanam-do, Republic of Korea. The existence of Cryptosporidium oocysts was confirmed using a modified Ziehl-Neelsen stain. Human infections were found in 7 (25.9%) of 27 people examined. Cattle cryptosporidiosis cases constituted 7 (41.2%) of 17 examined, and goat cases 3 (42.9%) of 7 examined. Species characterizations were performed on the small subunit of the rRNA gene using both PCR-RFLP and sequence analysis. Most of the human isolates were mixtures of C. hominis and C. parvum genotypes and similar PCR-RFLP patterns were observed in cattle and goat isolates. However, sequence analyses identified only C. hominis in all isolates examined. The natural infection of cattle and goats with C. hominis is a new and unique finding in the present study. It is suggested that human cryptosporidiosis in the studied area is caused by mixtures of C. hominis and C. parvum oocysts originating from both inhabitants and domestic animals.

New genotypes and factors associated with Cryptosporidium detection in mussels (Mytilus spp.) along the California coast

A 3 year study was conducted to evaluate mussels as bioindicators of faecal contamination in coastal ecosystems of California. Haemolymph samples from 4680 mussels (Mytilus spp.) were tested for Cryptosporidium genotypes using PCR amplification and DNA sequence analysis. Our hypotheses were that mussels collected from sites near livestock runoff or human sewage outflow would be more likely to contain the faecal pathogen Cryptosporidium than mussels collected distant to these sites, and that the prevalence would be greatest during the wet season when runoff into the nearshore marine environment was highest. To test these hypotheses, 156 batches of sentinel mussels were collected quarterly at nearshore marine sites considered at higher risk for exposure to livestock runoff, higher risk for exposure to human sewage, or lower risk for exposure to both faecal sources. Cryptosporidium genotypes detected in Haemolymph samples from individual mussels included Cryptosporidium parvum, Cryptosporidium felis, Cryptosporidium andersoni, and two novel Cryptosporidium spp. Factors significantly associated with detection of Cryptosporidium spp. in mussel batches were exposure to freshwater outflow and mussel collection within a week following a precipitation event. Detection of Cryptosporidium spp. was not associated with higher or lower risk status for exposure to livestock faeces or human sewage sources. This study showed that mussels can be used to monitor water quality in California and suggests that humans and animals ingesting faecal-contaminated water and shellfish may be exposed to both host-specific and anthropozoonotic Cryptosporidium genotypes of public health significance.

Parasitic infections in HIV-infected patients who visited Seoul National University Hospital during the period 1995-2003

The prevalence of parasitic infections was investigated in human immunodeficiency virus (HIV)-infected patients (n = 105) who visited Seoul National University Hospital, Seoul, Korea, during the period from 1995 to 2003. Fecal samples were collected from 67 patients for intestinal parasite examinations, and sputum or bronchoalveolar lavage samples from 60 patients for examination of Pneumocystis carinii. Both samples were obtained from 22 patients. Thirty-three (31.4%) of the 105 were found to have parasitic infections; Cryptosporidium parvum (10.5%; 7/67), Isospora belli (7.5%; 5/67), Clonorchis sinensis (3.0%; 2/67), Giardia lamblia (1.5%; 1/67), Gymnophalloides seoi (1.5%; 1/67), and Pneumocystis carinii (28.3%; 17/60). The hospital records of the 11 intestinal parasite-infected patients showed that all suffered from diarrhea. This study shows that parasitic infections are important clinical complications in HIV-infected patients in the Republic of Korea.

Genotype and animal infectivity of a human isolate of Cryptosporidium parvum in the Republic of Korea

Cryptosporidium parvum oocysts were isolated from a child suffering from acute gastroenteritis and successfully passaged in a calf and mice (designated hereafter SNU-H1) in the Republic of Korea; its molecular genotype has been analyzed. The GAG microsatellite region was amplified by a polymerase chain reaction (PCR), with a 238 base pair product, which is commonly displayed in C. parvum. The isolate was shown to be a mixture of the genotypes 1 (anthroponotic) and 2 (zoonotic). To study its infectivity in animals, 2 calves and 3 strains of mice were infected with the SNU-H1; in these animals, the propagation of both genotypes was successful. In immunosuppressed (ImSP) BALB/c and C57BL/6 mice the number of oocysts decreased after day 10 post-infection (PI); but in ImSP ICR mice, they remained constant until day 27 PI. The results show that both the C. parvum genotypes 1 and 2 can be propagated in calves and ImSP mice.

Aging and infectious diseases in the developing world

Although demographic aging does not remain restricted to industrialized countries, the medical challenge arising from the aging population will be distinct in the developing world. This is particularly true with respect to infectious diseases, which have a distinct spectrum in the elderly population, as well as a greater overall relevance in the developing world. Tropical diseases have a specific presentation and epidemiology in elderly patients. Infectious diseases with a worldwide distribution impact elderly patients in the developing world in a specific manner, which is most obvious with respect to human immunodeficiency virus and tuberculosis but is also true with respect to "trivial" manifestations of infection, such as diarrhea and pneumonia. Malnutrition contributes in a major way to the immunodeficiency of elderly patients in the developing world. Poorly controlled use of antimicrobial drugs leads to multidrug-resistant microorganisms, which, together with the limited resources available for drug treatment, makes appropriate treatment of infections in elderly patients in developing countries very difficult. Infections in elderly patients will have an increasing impact on the public health and economy of developing countries.

Prevalence of cryptosporidiosis among the villagers and domestic animals in several rural areas of Korea

The present study was undertaken to investigate the infection status of Cryptosporidium parvum in the villagers and the reservoir hosts in several rural areas in Korea. A total 5,262 fecal samples were collected from the inhabitants residing at Gangwon-do, Chungcheongbuk-do, Jeollanam-do, and Gyeongsangnam-do between the dates of September, 2001 to June, 2002. In addition, 1,453 fecal samples were collected from livestock reared in Gokseong-gun, Jeollanam-do and Chungju-si, Chungcheongbuk-do. All the fecal smears were prepared by formalin-ether sedimentation, and examined by light microscopy after modified acid-fast staining. The overall positive rate of human cryptosporidiosis was 3.3%. Gokseong-gun, Jeollanam-do showed a 8.2% positive rate and appeared as the highest endemic area among the surveyed areas. Haman-gun, Gyeongsangnam-do showed a 0.4% positive rate and was the lowest endemic area. The positive rate of livestock infection in Gokseong-gun, Jeollanam-do was 94%, which was more than ten times higher than that of Chungju-si, Chungcheongbuk-do (9.3%). From these results, it was revealed that cryptosporidiosis was an endemic disease in some rural areas of Korea, and the livestock could be an important source of human infection.

Infection status of pigs with Cryptosporidium parvum

To investigate the infection status of pigs with Cryptosporidium parvum, 589 fecal samples were collected from pigs raised at farm in Chungcheongbuk-do and Chungcheongnam-do. Of the 589 pig fecal samples, 62 (10.5%) were positive for C. parvum. The area showing the highest positive rate was Dangjin-gun, Chungcheongnam-do (14.0%), and the lowest (0%) Salmi-myon, Chungcheongbuk-do. The positive rate of C. parvum in Judok-eup increased from 12.7% in the winter to 22.1% in the summer. The results of this study suggest that the pigs may be a source of human C. parvum infection.

Significance of Cryptosporidium as an aetiology of acute infectious diarrhoea in elderly Indians

OBJECTIVE

To explore the significance of Cryptosporidium isolation in elderly Indian with acute infectious diarrhoea and its clinical correlates.

DESIGN

A hospital-based clinico-aetiological study of 120 patients aged 60 years or older, 25 adults younger than 60 years and 25 children up to age 14 with acute diarrhoea, and 57 apparently healthy elderly individuals.

RESULTS

Cryptosporidium was isolated in 22 older patients with diarrhoea (18.3%) and was highly significant (P < 0.01) compared with healthy age-matched controls. Of these patients 66% had a history of close contact with animals. Most (68%) Cryptosporidium infections occurred during the rainy season. Among the elderly patients 17% suffered from vomiting and abdominal pain, 31% were febrile; none were severely dehydrated. Stools numbered three to nine per day with duration of 5-17 days. Stool leucocytes were <6/hpf and no RBCs were seen. Isolation of Cryptosporidium in older persons was associated with diabetes mellitus (22.7%), tuberculosis (9.0%), malignancy (4.5%) and coronary artery disease (4.5%).

CONCLUSION

Cryptosporidium is an important cause of diarrhoea in elderly Indians, especially those with close contact with animals. The infection has a mild clinical course, is self-limiting and does not cause dysenteric stool. Its effect on nutrition requires further study.