• Parasites, Hosts and Diseases
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• v.41 no.3
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• pp.147-154
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• 2003

Toxoplasma gondii tachyzoites were isolated from the blood of an ocular patient, and have been successfully passaged in the laboratory, for over a year, by peritoneal inoculation in mice. The isolated parasite was designated the Korean Isolate-1 (KI-1) and its characteristics were compared with those of the RH strain, a well-known virulent strain originating from a child who suffered from encephalitis. The morphology, pathogenicity, infectivity and cell culture characteristics of the KI-1 were similar to those of the RH strain. Both RH and KI-1 antigens were detected by an anti-T gondii monoclonal antibody (mAb), Tg563, against the major surface protein SAG1 (30 kDa), whereas no reaction was observed against an anti-Neospora caninum mAb, 12B4. The KI-1 was confirmed as an isolate of T. gondii. A long-term laboratory maintenance and characterization of a local T gondii isolate is reported for the first time in the Republic of Korea.

• Korean journal of applied entomology
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• v.34 no.3
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• pp.218-223
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• 1995

A nuclear polyhedrosis virus isolated from the oriental tobacco budworm larvae, Helicoverpa assulta (Guenee) was characterized by electron microscopy, SDS-PAGE, restriction endonuclease analysis and cross infectivity. The shape of a polyhedron was $1.0\mu\textrm{m}$ in average with icosahdral outline, and the virus particle was $65nm\times300nm$ in average with rod-shape. The nuclear polyhedrosis virus was contained a single nucleocapsid within a viral envelope embedded in a polyhedron. The polyhedral protein was composed of a single polypeptide with a M.W. of 31 Kd. The genome size of the virus by restriction endonuclease analysis was about 120 Kb. Among several nuclear polyhedrosis viruses, the nuclear polyhedrosis virus from Helicoverpa assulta (HaNPV) and Autographa california nuclear polyhedrosis virus (AcNPV) were infected the oriental tobacco budworm larvae.

• Safety and Health at Work
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• v.3 no.3
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• pp.209-215
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• 2012

Objectives: Knowledge, attitudes, and practices of healthcare providers related to occupational exposure to bloodborne pathogens were assessed in a tertiary-care hospital in Middle East. Methods: A cross-sectional study was undertaken using a self-administered questionnaire based on 3 paired (infectivity known vs. not known-suspected) case studies. Only 17 out of 230 respondents had an exposure in the 12 months prior to the survey and of these, only 2 had complied fully with the hospital's exposure reporting policy. Results: In the paired case studies, the theoretical responses of participating health professionals showed a greater preference for initiating self-directed treatment with antivirals or immunisation rather than complying with the hospital protocol, when the patient was known to be infected. The differences in practice when exposed to a patient with suspected blood pathogens compared to patient known to be infected was statistically significant (p < 0.001) in all 3 paired cases. Failure to test an infected patient's blood meant that an adequate risk assessment and appropriate secondary prevention could not be performed, and reflected the unwillingness to report the occupational exposure. Conclusion: Therefore, the study demonstrated that healthcare providers opted to treat themselves when exposed to patient with infectious disease, rather than comply with the hospital reporting and assessment protocol.

• Journal of Korean Society for Quality Management
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• v.48 no.3
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• pp.493-510
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• 2020

Purpose: As of July 31, there were 14,336 confirmed cases of COVID-19 in South Korea, including 301 deaths. Since the daily confirmed number of cases hit 909 on February 29, the spread of the disease had gradually decreased due to the active implementation of preventive control interventions, and the daily confirmed number had finally recorded a single digit on April 19. Since May, however, the disease has re-emerged and retaining after June. In order to eradicate the disease, it is necessary to suggest suitable forward preventive strategies by predicting future infectivity of the disease based on the cases so far. Therefore, in this study, we aim to evaluate the transmission potential of the disease in early phases by estimating basic reproduction number and assess the preventive control measures through effective reproduction number. Methods: We used publicly available cases and deaths data regarding COVID-19 in South Korea as of July 31. Using ensemble model integrated stochastic linear birth model and deterministic linear growth model, the basic reproduction number and the effective reproduction number were estimated. Results: Estimated basic reproduction number is 3.1 (95% CI: 3.0-3.2). Effective reproduction number was the highest with 7 on February 15, decreased as of April 20. Since then, the value is gradually increased to more than unity. Conclusion: Preventive policy such as wearing a mask and physical distancing campaigns in the early phase of the outbreak was fairly implemented. However, the infection potential increased due to weakening government policy on May 6. Our results suggest that it seems necessary to implement a stronger policy than the current level.

• The Journal of Korean Society of Virology
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• v.26 no.1
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• pp.67-76
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• 1996

The methods that make Hantavirus grow consist of inoculation into the experimental animals and cultured cells. The cultured cells, such as Vero-E6 and A549 cells, have been usually used for isolation of the virus and the animals, such as mice and rats, are used for large scale preparation of the virus so far. Furthermore, the cell can be used to maintain the virus and assay the infectivity and the animals can be used for the experiment of viral pathogenicity and challenge for assessment of vaccine. Apodemus mice, the own natural host of the virus, has been used for challenge test of Hantaan virus. However it has been pointed out to difficult handling and breeding the animal in laboratory. Therefore, we attempted to establish a new animal model for challenge test at the time of isolation of Maaji virus which is a new hantavirus similar but distinct to Hantaan virus. In suckling hamster, the titer of Maaji virus and the lethality to mice of the virus were increased gradually in the titer and lethality through passage by intracerebral (IC) inoculation. We tried to re-adapt this brain virus to lung of weanling hamster. The brain passaged virus was inoculated into weanling hamster intramuscularly. Again, the titer of the virus in lung was also increased by continuous passage of this virus. This facts could regarded as adaptation to new environment in which the virus proliferates. To identity the virus passaged in hamster with Maaji virus, both of the virus passaged in hamster brain and lung were compared with Maaji virus (MAA-I) and Hantaan virus (HTN 76-118) by means of restriction fragment length polymorphism (RFLP) and slingle strand conformation polymophism (SSCP). As a result, we conclude that Maaji virus could be adapted successfully to weanling hamster through this passage strategy. Utilizing this adapted Maaji virus strain, hamster model is able to be used for challenge test in hantaviral vaccinology and further experiments utilizing hamster system as a rather available and convenient lab animal are expected.

• The Journal of the Korean Society for Microbiology
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• v.35 no.1
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• pp.1-8
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• 2000

In order to explore the potential of ascorbic acid supplementation for the prevention and treatment of herpes simplex viral diseases, plaque reduction assays were performed. Ascorbic acid as well as copper chloride/ferric chloride were added to wells containing Vero cells infected with herpes simplex virus type 1 (HSV-1), and the infectivity of HSV-1 was determined. Since copper and iron are major transition metals in human plasma, near the normal human plasma concentrations of them were used for experiments. When Cu(II) and Fe(III) were applied, there were no significant differences between virus control and Cu(II)/Fe(III)-treated groups. But, when appropriate concentrations of ascorbic acid were added to wells, meaningful differences between control and ascorbate-treated groups were found. In the presence of Cu(II)/Fe(III) at $5.8/3.7\;{\mu}M$, 72-h treatment with ascorbate at $50\;{\mu}M$ reduced HSV-1 infections to $10.77%{\pm}4.25%$ (P < 0.001) and $500\;{\mu}M$ did to $3.06%{\pm}1.62%$ (P < 0.001). Moreover, the cytotoxicities for Vero cells at those concentrations were insignificant (P > 0.05). Current recommended dietary allowance (RDA) of ascorbic acid is 60 mg/day, and the oral intake of 60 mg/day of ascorbic acid yields plasma ascorbic acid at 45 to $58\;{\mu}M$ in a healthy adult man. Therefore, the results of this study suggest that the maintenance of appropriate level (more than $50\;{\mu}M$) of ascorbic acid in human plasma by appropriate amount (more than the RDA) of ascorbic acid supplementation may be helpful for the prevention and treatment of diseases caused by HSV -1 in an adult man. In addition, this study also suggests that ascorbic acid may be useful for the prophylaxis of fatal HSV-1 infections in neonates and the prevention of HSV-1 reactivation in immunocompromised hosts.

• Tuberculosis and Respiratory Diseases
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• v.81 no.3
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• pp.233-240
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• 2018

Background: Non-conversion of sputum smear and culture prolongs the infectivity of the patient and has been associated with unfavorable outcomes. We aimed to evaluate factors associated with persistent sputum positivity at the end of two months of treatment of new case pulmonary tuberculosis (TB). Methods: Data of 87 human immunodeficiency virus-negative patients with culture-positive drug-susceptible pulmonary TB admitted to local university hospital between September 2015 and September 2016 were reviewed. Factors associated with sputum smear and/or culture positivity at the end of the second month of treatment were analyzed. Results: Twenty-two patients (25.3%) remained smear and/or culture-positive. Male sex, lower body mass index (BMI), unemployment, alcohol abuse, higher number of lobes involved and cavities on chest X-rays, shorter time to detection (TTD) on liquid cultures, higher respiratory sample smear grading and colony count in solid cultures, higher C-reactive protein, erythrocyte sedimentation rate, leukocytosis, thrombocytosis, and anemia were all significantly associated with persistent sputum positivity. However, in the logistic regression analysis only male sex, lower BMI, alcohol abuse, higher radiological involvement, cavitation, higher smear grading, higher colony count in solid cultures and shorter TTD were determined as independent factors associated with persistent sputum positivity at the end of 2 months of treatment. Conclusion: In conclusion, higher sputum smear and culture grading at diagnosis, shorter TTD, higher number of lobes involved, cavitation, male sex, alcohol abuse, and lower BMI were independently associated with persistent sputum positivity. These factors should be sought when distinguishing which patients will remain infectious longer and possibly have worse outcomes.

• Tuberculosis and Respiratory Diseases
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• v.81 no.3
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• pp.241-246
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• 2018

Background: The "Tuberculosis Relief Belt Supporting Project (Tuberculosis Patient Management Project for Poverty Groups)" is a national program for socioeconomically vulnerable tuberculosis (TB) patients. We sought to evaluate the clinical and socioeconomic characteristics of poverty-stricken TB patients, and determined the need for relief. Methods: We examined in-patients with TB, who were supported by this project at the National Medical Center from 2014 to 2015. We retrospectively investigated the patients' socioeconomic status, clinical characteristics, and project expenditures. Results: Fifty-eight patients were enrolled. Among 55 patients with known income status, 24 (43.6%) had no income. Most patients (80%) lived alone. A total of 48 patients (82.8%) had more than one underlying disease. More than half of the enrolled patients (30 patients, 51.7%) had smear-positive TB. Cavitary disease was found in 38 patients (65.5%). Among the 38 patients with known resistance status, 19 (50%) had drug-resistant TB. In terms of disease severity, 96.6% of the cases had moderate-to-severe disease. A total of 14 patients (26.4%) died during treatment. Nursing expenses were supported for 12 patients (20.7%), with patient transportation costs reimbursed for 35 patients (60%). In terms of treatment expenses for 31 people (53.4%), 93.5% of them were supported by uninsured benefits. Conclusion: Underlying disease, infectivity, drug resistance, severity, and death occurred frequently in socioeconomically vulnerable patients with TB. Many uninsured treatment costs were not supported by the current government TB programs, and the "Tuberculosis Relief Belt Supporting Project" compensated for these limitations.

• Journal of The Korean Dental Society of Anesthesiology
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• v.14 no.4
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• pp.237-241
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• 2014

Acquired Immune Deficiency Syndrome is the state which develops after complications with the infection from HIV. Irrespective of their state, all HIV infections have infectivity. According to a 2013 U.N. AIDS global report, the number of reported newly infected with HIV is constantly falling, while that of Korea has been increasing over recent years and it surpassed 10,000 in 2013. This phenomenon might be attributed to the unusualness of the blood test for early detection of HIV infection. From this fact, we can assume that we have strong possibilities for encounters with infections in the office. But many misconceptions about the disease makes patients try to hide their medical history, which can lead to a nationwide spread of the infection without proper management. Even though it may be difficult to take care of HIV patients in smaller dental offices, large scale hospitals have the means to arrange protocols to treat them. We present a case about dental treatment of a patient with AIDS that has a history of cerebral infarction and hepatitis type B under general anesthesia. The purpose of this case report was to discuss the special considerations of dental care for patients with HIV.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.235-238
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• 2016

Hepatitis C is an ailment of liver caused by hepatitis C virus (HCV) infection. About 3% of the world population is infected by this virus. HCV infection is a leading reason for liver cirrhosis and therefore a major source of hepatocellular carcinoma. The study focused on the incidence of active HCV infection in blood donors of Mardan district of KPK, Pakistan. A total of 5318 blood donors were inspected for the presence of anti-HCV antibodies and HCV-RNA using ICT (immune-chromatographic test), ELISA and RT-PCR at Mardan Medical Complex (MMC), Mardan. Out of these, 157 (2.95%) were positive by ICT, 60 (1.12%) by ELISA and 56 (1.05%) for HCV-RNA. The frequency of active HCV infectivity amongst the blood donors from district Mardan, KPK Pakistan was 1.05 %. Application of strict measures during blood donor selection and use of proper screening assays such as ELISA in place of ICT devices can give a more accurate picture so that the incidence of this viral infection in HCV negative blood recipients can be reduced.