• Korean Journal of Veterinary Service
• /
• v.30 no.1
• /
• pp.133-144
• /
• 2007

This study was conducted to determine the effective environmental control measures in preventing calf diarrheal disease in farms. It was found that the high numbers of calves in a cow house was directly related with the high incidence rate of diarrheal diseases. When the number of calves was increased in a cow house, it was difficult to reduce the diarrheal diseases of calves. It was revealed that the incidence rates of calf diarrheal disease were dramatically reduced when the delivery house which faced south. The periodical changes of bedding materials seemed beneficial good to control the possible resident infectious agents, including pathogenic viruses and bacteria. The control of the delivery time was important for reduction of calf diarrhea. It was revealed that September and October were the best time as the delivery period. In order to use old cow house as a delivery house, it should be sterilized by the disinfectant and the flame. When the diarrheal feces were removed as soon as possible, the transmission of diarrheal diseases among calves In the same house was reduced. When the diarrheal feces were not disposed, the incidence rate of diarrhea reached up to 50%. When the morbid calves were not quarantined, the incidence rate of diarrhea was 100%. In contrast, when the diseased calves were quarantined from other calves, the incidence rate of diarrhea was reduced, remarkably. The mean recovery time from the diarrhea of the treated calves in the southern cow house was much faster than that in the north cow house. The treatment of calves in a clean and well-ventilated cow house with dry bedding was more effective than that in a cold, wet, and dark house. It could be postulated that the most important environmental factor in the reduction of diarrheal diseases of calves is the blocking of the entry of the infectious agents. The complete sanitation and control of the delivery house in the using farm is more important than building a new cow house, for prevention of calf diarrheal diseases.

• Parasites, Hosts and Diseases
• /
• v.48 no.2
• /
• pp.113-120
• /
• 2010

To understand protozoan, viral, and bacterial infections in diarrheal patients, we analyzed positivity and mixedinfection status with 3 protozoans, 4 viruses, and 10 bacteria in hospitalized diarrheal patients during 2004-2006 in the Republic of Korea. A total of 76,652 stool samples were collected from 96 hospitals across the nation. The positivity for protozoa, viruses, and bacteria was 129, 1,759, and 1,797 per 10,000 persons, respectively. Especially, Cryptosporidium parvum was highly mixed-infected with rotavirus among pediatric diarrheal patients (29.5 per 100 C. parvum positive cases), and Entamoeba histolytica was mixed-infected with Clostridium perfringens (10.3 per 100 E. histolytica positive cases) in protozoan-diarrheal patients. Those infected with rotavirus and C. perfringens constituted relatively high proportions among mixed infection cases from January to April. The positivity for rotavirus among viral infection for those aged $\leq$ 5 years was significantly higher, while C. perfringens among bacterial infection was higher for $\geq$ 50 years. The information for association of viral and bacterial infections with enteropathogenic protozoa in diarrheal patients may contribute to improvement of care for diarrhea as well as development of control strategies for diarrheal diseases in Korea.

• Proceedings of the Microbiological Society of Korea Conference
• /
• 2000.05a
• /
• pp.58-65
• /
• 2000

Diarrheal diseases are a major cause of both illness and death in developing countries and are caused by rotavirus, Shigella spp., Salmonella spp., enterotoxigenic Escherichia coli (ETEC), and Vibrio spp. In this study, for the development of vaccine against diarrheal diseases caused by Shigella sonei, Salmonella typhimurium, E. coli O157, and Vibrio cholerae, cloning and nucleotide sequence analysis of genes and characteristics of their gene products in E. coli were performed. For construction of attenuated strain of S. sonnei KNIH104 and Salmonella typhimurium KNIH100, the aroA genes were cloned, respectively. The recombinant plasmid $_pJP{\Delta}A45$ containing aroA deleted region and suicide vector $(_pJP5603)$ was constructed. The aroA gene deleted mutants were constructed using this recombinant plasmid. For cloning gene encoding antigenic region of E. coli O157 KNIH317, the O-antigen synthesis gene cluster and sit gene was cloned. The E. coli XL1-Blue cells harboring this recombinant plasmid showed cytotoxicity in Vero cells. The ctx gene was cloned for tile purpose of antigenic region against V. cholerae KNIH002. Sequence analysis confirmed that the virulence gene cassette was consisted of ace, zot, ctxA and ctxB genes.

• Pediatric Infection and Vaccine
• /
• v.16 no.2
• /
• pp.115-122
• /
• 2009

Diarrhea is one of the most common causes of morbidity and mortality in children worldwide. Rotavirus is the most common cause of infectious diarrhea both in developed and developing countries. However, bacterial causes such as Salmonella typhi and Vibrio cholerae still play an important role in developing countries. Newly developed vaccines for rotavirus, S. typhi, and V. choleae are highly immunogenic and safe in children.

• Parasites, Hosts and Diseases
• /
• v.54 no.3
• /
• pp.339-344
• /
• 2016

The genus Sarcocystis is not usually considered as an important enteric pathogen in immune compromised patients. It might be expected that species for which humans are the final host (Sarcocystis hominis and Sarcocystis suihominis as well as possibly others) would be encountered increasingly often in immunodeficient persons. This study aimed to address how to detect and differentiate Sarcocystis oocysts and/or sporocysts from enteric protozoans in the diarrheal samples of immunodeficient patients in Shiraz, Iran. Diarrheal samples of 741 immunodeficient patients with recurrent persistent or chronic diarrhea were examined by microscopy and molecular biological analysis. Oocysts-positive samples were 68 Cryptosporidium spp., 9 Cystoisospora belli (syn. Isospora belli), 2 Cyclospora cayetanensis, and 15 microsporidia (Enterocytozoon bieneusi). Sarcocystis-like sporocysts found from a woman were identified as Sarcocystis cruzi through 18S rDNA amplification and phylogenetic analysis. To the best of our knowledge, this is the first report of S. cruzi from a human.

• Parasites, Hosts and Diseases
• /
• v.59 no.1
• /
• pp.61-65
• /
• 2021

Diarrheal disease is the second leading cause of mortality and morbidity in children under 5 years old worldwide, and is the most common cause of malnutrition in sub-Saharan Africa. In Rwanda, diarrhea is the third leading cause of death in children under 5 years old. This study examined the association between sociodemographic factors and diarrhea in children under 5 years using the data of 7,474 households in the 2014-2015 Rwanda Demographic and Health Survey. Overall prevalence of diarrhea in this study was 12.7% in children. An increased risk for diarrhea was found for children aged 12-23 months (odds ratio (OR)=4.514), those with a low economic status (OR=1.64), those from the Western province (OR=1.439), those with poorly-educated mothers (OR=5.163), and those with families engaged in agricultural activities (OR=1.624). In conclusion, sociodemographic factors significantly affect the risk of developing diarrhea in children under 5 years in Rwanda. Designing and implementing health education promoting awareness of early interventions and rotavirus vaccination are essential to reduce diarrheal diseases for the Rwandan community.

• Parasites, Hosts and Diseases
• /
• v.58 no.5
• /
• pp.589-592
• /
• 2020

Cyclospora cayetanensis is an apicomplexan protozoan and is one of the most common pathogens causing chronic diarrhea worldwide. Eight stool samples with diarrheal symptom out of 18 Korean residents who traveled to Nepal were obtained, and examined for 25 enteropathogens including 16 bacterial species, 5 viral species, and 4 protozoans in stool samples as causative agents of water-borne and food-borne disease. Only C. cayetanensis was detected by nested PCR, and 3 PCR-positive samples were sequenced to confirm species identification. However, the oocysts of C. cayetanensis in fecal samples could not be detected by direct microscopy of the stained sample. As far as we know, this is the first report of a group infection with C. cayetanensis from a traveler visiting Nepal, and the second report of a traveler's diarrhea by C. cayetanensis imported in Korea.

• Parasites, Hosts and Diseases
• /
• v.59 no.4
• /
• pp.409-413
• /
• 2021

In this study, we have collected and screened a total of 268 stool samples from diarrheal patients admitted to an Infectious disease hospital in Kolkata for the presence of Cryptosporidium spp. The initial diagnosis was carried out by microscopy followed by genus specific polymerase chain reaction assays based on 70 kDa heat shock proteins (HSP70). DNA sequencing of the amplified locus has been employed for determination of genetic diversity of the local isolates. Out of 268 collected samples, 12 (4.48%) were positive for Cryptosporidium spp. Sequences analysis of 70 kDa heat shock proteins locus in 12 Cryptosporidium local isolates revealed that 2.24% and 1.86% of samples were showing 99% to 100% identity with C. parvum and C. hominis. Along with the other 2 major species one recently described globally distributed pathogenic species Cryptosporidium viatorum has been identified. The HSP70 locus sequence of the isolate showed 100% similarity with a previously described isolate of C. viatorum (Accession No. JX978274.1, JX978273.1, and JN846706.1) present in GenBank.

• 한국환경농학회:학술대회논문집
• /
• 2009.07a
• /
• pp.228-239
• /
• 2009

The observations on climate change show a clear increase in the temperature of the Earth's surface and the oceans, a reduction in the land snow cover, and melting of the sea ice and glaciers. The effects of climate change are likely to include more variable weather, heat waves, increased mean temperature, rains, flooding and droughts. The threat of climate change and global warming on human and animal health is now recognized as a global issue. This presentation is described an overview of the latest scientific knowledge on the impact of climate change on zoonotic diseases. Climate strongly affects agriculture and livestock production and influences animal diseases, vectors and pathogens, and their habitat. Global warming are likely to change the temporal and geographical distribution of infectious diseases, including those that are vector-borne such as West Nile fever, Rift Valley fever, Japanese encephalitis, bluetongue, malaria and visceral leishmaniasis, and other diarrheal diseases. The distribution and prevalence of vector-borne diseases may be the most significant effect of climate change. The impact of climate change on the emergence and re-emergence of animal diseases has been confirmed by a majority of countries. Emerging zoonotic diseases are increasingly recognized as a global and regional issue with potential serious human health and economic impacts and their current upward trends are likely to continue. Coordinated international responses are therefore essential across veterinary and human health sectors, regions and countries to control and prevent emerging zoonoses. A new early warning and alert systems is developing and introducing for enhancing surveillance and response to zoonotic diseases. And international networks that include public health, research, medical and veterinary laboratories working with zoonotic pathogens should be established and strengthened. Facing this challenging future, the long-term strategies for zoonotic diseases that may be affected by climate change is need for better prevention and control measures in susceptible livestock, wildlife and vectors in Korea. In conclusion, strengthening global, regional and national early warning systems is extremely important, as are coordinated research programmes and subsequent prevention and control measures, and need for the global surveillance network essential for early detection of zoonotic diseases.

• Journal of agricultural medicine and community health
• /
• v.44 no.2
• /
• pp.65-72
• /
• 2019

This study aimed to identify the prevalence of communicable diseases at household level and associated risk factors among urban slum residents of Rupandehi district of Nepal. A cross-sectional study was carried out among a total of 259 purposively selected households in the urban slum of Butwal sub-metropolitan city, Rupandehi, Nepal between 25 November and 7 December, 2018. Prevalence of communicable diseases in the households within past one year were reported followed by assessment of risk factors associated with prevalence of communicable diseases using multivariable logistic regression analysis. The study result revealed that out of 259 study participants, more than two third (71.8%) reported to have at least any one of the communicable diseases in the household within past one year, and most common (91.9 %) reported to have cold and cough and diarrheal diseases. Final multivariable logistic regression analysis showed that study participants who did not have appropriate lightening in their houses were more likely (aOR 2.75; 95% CI (1.356-5.586)) to have communicable diseases. This study recommends understanding of the existing prevalence of communicable diseases and risk associated with it while designing health promotion activities and appropriate urban planning in Nepal.