• Journal of agricultural medicine and community health
• /
• v.7 no.1
• /
• pp.66-73
• /
• 1982

Paragonimus westermani is one of the most popular endemic parasitic diseases in Korea. The nation-wide prevalence survey were carried out by Gobayashi (1921) with sputum examination and by Walton and Chyu (1959) with the intradermal skin test respectively. Recent studies showed the decline of positive rate in intradermal skin test of the local inhabitants and also showed the less distribution of intermediate host. The fact seemed that caused by economic improvement of village people, decrease of intermediate host by increasing use of pesticides, becoming lower water level at streams and rivers and better irrigation and finally by better community health education etc. Gangwha area of Gyeonggi-Do was found out as an endemic area of Paragonimus westermani through some studies in the past, however, in the vicinity area of Gangwha, the study in Kyodong island (myon) was carried out in 1965 by Yun et al. Therefore author carried out the intradermal skin test for 2,380 students of primary, middle and high school in Kyodong island and Samsan island. The results showed as follows : 1) The positive rate of intradermal test for paragonimus westermani infection showed positive in 152 among 1,845 students (8.2%) in Kyodong island, and 21 among 637 students (3.3%) in Samsan island respectively. 2) According to grade levels, 49 among 973 students (5.0%) in primary school, 62 among 962 students (6.4%) in middle school and 53 among 445 students (11.9%) in high school showed positive rate. This showed the higher grade the higher positive rate. 3) Among these total 164 positive cases in the intradermal skin test, only in 3 cases eggs were found in sputum. 4) Finding out the intermediate host, only 28 crayfishes from Kyodong island and 12 from Samsan island were collected and examined for metacercaria infection, however, none of metacercaria was found. 5) As a control group, 2 primary schools from the main island were selected. In these schools from the sixth grade students showed positive rate of 4.8% in Naega primary school and 0% in Hajeom Primary school respectively. Those results showed much decrease than studies carried out in the past. 6) The survey for food habit showed that 15 among 1,274 students (1.2%) had experiences of eating raw intermediate host(crayfish) and 266 among 988 students (27.0%) ate cooked.

• Tuberculosis and Respiratory Diseases
• /
• v.66 no.2
• /
• pp.116-121
• /
• 2009

Background: Tsutsugamushi, leptospirosis and hemorrhagic fever with renal syndrome (HFRS) are the prevalent diseases among the acute febrile illnesses in Korea. Pulmonary involvement in the patients with these diseases remains poorly recognized in endemic regions, and this is despite reports of recent outbreaks and epidemic episodes. Pulmonary involvement and a higher CRP level as clinical manifestations show a more severe form of infection. The aim of this study is to analyze the correlation of pulmonary involvement and the CRP level in patients with acute febrile illnesses. Methods: We retrospectively reviewed the clinical records of 105 patients who were diagnosed with tsutsugamushi, HFRS and leptospirosis from January 2002 to May 2008 in Chuncheon Sacred Heart Hospital. The radiographic images were retrospectively analyzed by two radiologists. We analyzed the pulmonary complications of the patients with these febrile diseases and we checked the CRP level at admission. Results: The study included 105 patients who were diagnosed with febrile diseases. Of these patients, 32 patients had hantaan, 10 patients had leptospirosis and 63 patients had tsutsugamushi disease. 42 (40%) patients had pulmonary complications, 20 patients had pulmonary edema, 20 patients had pleural effusion and 2 patients had interstitial pneumonitis. The patients with pulmonary involvement showed a more severe form of infection and a higher CRP level than that of those patients without pulmonary involvement (p=0.0073). Conclusion: Pulmonary involvement in patients with acute febrile diseases might be correlated with a higher CRP level. Identification of this factor on admission might provide useful selection criteria for the patients who need early intensive care.

• Journal of agricultural medicine and community health
• /
• v.13 no.1
• /
• pp.82-87
• /
• 1988

사람의 흡충류감염(吸蟲類感染)은 대부분(大部分) 열대(熟帶) 및 동부아세아지역(東部亞細亞地域) 여러 국가(國家)에서 발생(發生)한다. 주혈흡충증(住血吸蟲症), 간흡충증(肝吸蟲症), 태국간흡충증(泰國肝吸蟲症), 간흡충증(肝吸蟲症), 요꼬가와흡충증(吸蟲症), 이형이형흡충증(異型異型吸蟲症) 및 폐대흡충증(肺大吸蟲症)등은 어떤 일부(一部) 아세아국가(亞細亞國家)에 있어서 공중보건상(公衆保健上) 중요(重要)한 문제(間題)가 되어 있다. 이와 같은 패류매개성기생충감염(貝類媒介性寄生蟲感染)은 풍토병(風土病)을 일으키고 있다. 사람들의 생활습관은 풍토병을 일으키게될 원인이 될 뿐만 아니라 때로는 그 질병(疾病)을 유행(流行) 전파(傳播)시키는 기본적 요소가 되기도 한다. 주혈흡충을 제외한 흡충류감염은 우리가 중간숙주(中間宿主)을 먹었을때 그곳에 있었던 피낭유충(被囊幼蟲)에 의하여 감염이 이루어 진다. 식물(植物)의 생식(生殖)(간질(肝蛭), 폐대흡충(肺大吸蟲)), 게 및 가재 생식(폐흡충), 민물고기 생식(간흡충, 요꼬가와흡충, 이형이형흡충), 또는 우렁이 생식(극구흡충(棘口吸蟲)), 기타(몇가지 우연적감염(偶然的感染))등은 사람의 흡충류감염의 주 원인이 되는 것이다. 한편 주혈흡충 감염은 요염수원(汚染水源)에 접촉한 피부을 뚫고 들어온 쎌카리아 유충(幼蟲)에 노출되기 때문에 일어난다. 흡충류감염에 대하여 예방과 방어에 관한 공중보건학적 조치는 많다. 이들의 조치중에는 화학요법에 의한 감염원을 감소시키는 것, 패류숙주의 박멸, 만족할만한 위생시설의 비치, 급수시설, 보건교육, 진단기술의 보급, 환경관리 및 개선 등이 포함된다. 그러나 감염자들에 대한 화학요법은 가장 빠르고 효과적인 억제방법인 것으로 나타나고 있다. 흡충류감염을 예방하는데 있어서 가장 중요한 변화는 프라지콴텔과 같은 신약의 개발이었다. 프라지콴텔은 모든 종류의 주혈흡충, 간흡충, 폐흡충 및 여러가지 장내기생 흡충류등 사람의 병원성흡충류에 대한 치료제로서 가장 좋은 특효약이다. 흡충류감염이 중요한 보건문제가 되어 있는 곳에서는 그 예방과 억제책에 있어서 장단기계획(長短期計劃)을 수립하는 것이 좋을 것 같다. 단기는 집단화학요법을 조기에 실시하여야 하고 자기는 "비특이성 기구"로써, 예를들면 위생시설 및 급수시설의 설치, 보건교육등으로 감염을 감소시켜 감염유지 수준이하로 보지(保持)시키는 것이다. 이와같은 억제조치를 착실히 수행하기 위하여 많은일이 있다. 예를 들면 집단참여, 역학적 조사, 약물의 공급, 환경관리, 보건교육, 지역사회관련, 일차보건 진료와의 협조 및 재정후원등에 대하여 검토하고 연구하여야 할 것이다.

• Parasites, Hosts and Diseases
• /
• v.47 no.3
• /
• pp.213-218
• /
• 2009

Leishmaniasis is a neglected disease and endemic in developing countries. A lack of adequate and definitive chemotherapeutic agents to fight against this infection has led to the investigation of numerous compounds. The aim of this study was to investigate the effect of RT-01, an organotellurane compound presenting biological activities, in 2 experimental systems against Leishmania amazonensis. The in vitro system consisted of promastigotes and amastigotes forms of the parasite, and the in vivo system consisted of L.amazonensis infected BALB/c mice, an extremely susceptible mouse strain. The compound proved to be toxic against promastigotes and amastigotes. The study also showed that treatment with RT-01 produces an effect similar to that treatment with the reference antimonial drug, Glucantime, in L.amazonensis infected mice. The best results were obtained following RT-01 intralesional administration (720 ${\mu}g$/kg/day); mice showed significant delay in the development of cutaneous lesions and decreased numbers of parasites obtained from the lesions. Significant differences in tissue pathology consisted mainly of no expressive accumulation of inflammatory cells and wellpreserved structures in the skin tissue of RT-01-treated mice compared with expressive infiltration of infected cells replacing the skin tissue in lesions of untreated mice. These findings highlight the fact that the apparent potency of organotellurane compounds, together with their relatively simple structure, may represent a new avenue for the development of novel drugs to combat parasitic diseases.

• Parasites, Hosts and Diseases
• /
• v.48 no.1
• /
• pp.81-83
• /
• 2010

To figure out the geographical distribution of Gynaecotyla squatarolae and Microphallus koreana metacercariae in Korea, shore crabs of southwestern coastal areas were examined. Eight coastal areas in Inchon-si (A), Gyeonggi-do (B), Chungcheongnam-do (C, D, and E), Jeollabuk-do (F), and Jeollanam-do (G and H) were selected, and 2 kinds of crabs, Macrophthalmus dilatatus and/or Macrophthalmus japonicus, were caught. After transportation to the laboratory, 15 crabs per each group were grouped and ground in a mortar and pestle, and examined for microphallid metacercariae. In M. dilatatus, G. squatarolae metacercariae were recovered from 3 (C, E, and H) out of 6 regions, but M. koreana metacercariae were not recovered. In the case of M. japonicus, G. squatarolae metacercariae were recovered from 6 (B, D, E, F, G, and H) of 7 areas surveyed, and M. koreana matacercariae were detected from 5 regions (A, B, D, F, and H). These results indicate that the life cycle of G. squatarolae is maintained in the western coastal areas using M. dilatatus and M. japonicus as intermediate hosts, while that of M. koreana is maintained only using M. japonicus.

• Korean Journal of Clinical Laboratory Science
• /
• v.43 no.4
• /
• pp.150-155
• /
• 2011

It is a very important diagnosis and evalution of Hepatocellular carcinoma (HCC) in Korea where hepatitis B-virus is endemic. Protein induced by vitamin K absence or antagonist II (PIVKA-II) appears to be a useful tumor marker. This study was purposed to investigate usefulness of PIVKA-II in the diagnosis and fallow-up after treatment of HCC. A total of 418 patients were included in 187 patients (44.7%) of HCC, 83 patients (19.9%) of liver cirrhosis, 74 patients (17.7%) of chronic hepatitis and 74 patients (17.7%) of other liver diseases with serum PIVKA-II levels by Hicatch PIVKA-II kit. PIVKA-II level were analysed for difference of groups and the comparison of treatment responses. The sensitivity and specificity of PIVKA-II in the diagnosis of HCC were 80.2%, 87.0% at the cut-off value of 40 mAU/mL. There were statistically significant difference between the HCC and other groups (p<0.001), before and after PIVKA-II levels after treatment in HCC (p<0.001). PIVKA-II can be used as a useful tumor marker for patients with HCC, especially early diagnosis in high risk groups, treatment response assesment and monitoring of recurrence.

• IMMUNE NETWORK
• /
• v.4 no.2
• /
• pp.73-80
• /
• 2004

Viruses are obligate intracellular parasites which cause infection by invading and replicating within cells. The immune system has mechanisms which can attack the virus in extracellular and intracellular phase of life cycle, and which involve both non-specific and specific effectors. The survival of viruses depends on the survival of their hosts, and therefore the immune system and viruses have evolved together. Immune responses to viral infection may be variable depending on the site of infection, the mechanism of cell-to-cell spread of virus, physiology of the host, host genetic variation, and environmental condition. Viral infection of cells directly stimulates the production of interferons and they induce antiviral state in the surrounding cells. Complement system is also involved in the elimination of viruses and establishes the first line of defence with other non-specific immunity. During the course of viral infection, antibody is most effective at an early stage, especially before the virus enters its target cells. The virus- specific cytotoxic T lymphocytes are the principal effector cells in clearing established viral infections. But many viruses have resistant mechanism to host immune responses in every step of viral infection to cells. Some viruses have immune evasion mechanism and establish latency or persistency indefinitely. Furthermore antibodies to some viruses can enhance the disease by the second infection. Immune responses to viral infection are very different from those to bacterial infection.

• Parasites, Hosts and Diseases
• /
• v.52 no.6
• /
• pp.639-644
• /
• 2014

Congenital malaria is assumed to be a risk factor for infant morbidity and mortality in endemic areas like Maumere, Indonesia. Infected infants are susceptible to its impact such as premature labor, low birth weight, anemia, and other unspecified symptoms. The aim of this study was to investigate the prevalence of congenital malaria and the influence of mother-infant paired parasite densities on the clinical outcome of the newborns at TC Hillers Hospital, Maumere. An analytical cross sectional study was carried out in newborns which showed criteria associated with congenital malaria. A thick and thin blood smear confirmed by nested PCR was performed in both mothers and infants. The association of congenital malaria with the newborn's health status was then assessed. From 112 mother-infant pairs included in this study, 92 were evaluated further. Thirty-nine infants (42.4%) were found to be infected and half of them were asymptomatic. Infected newborns had a 4.7 times higher risk in developing anemia compared to uninfected newborns (95% CI, 1.3-17.1). The hemoglobin level, erythrocyte amount, and hematocrit level were affected by the infants' parasite densities (P<0.05). Focusing on newborns at risk of congenital malaria, the prevalence is almost 3 times higher than in an unselected collective. Low birth weight, anemia, and pre-term birth were the most common features. Anemia seems to be significantly influenced by infant parasite densities but not by maternal parasitemia.

• Parasites, Hosts and Diseases
• /
• v.56 no.4
• /
• pp.391-396
• /
• 2018

Cystic echinococcosis (CE) caused by E. granulosus is a serious helminthic zoonosis in humans, livestock and wildlife. Xinjiang is one of high endemic province for CE in China. A total of 55 sheep and cattle livers containing echinococcal cysts were collected from slaughterhouses in Changji and Yining City, northern region of Xinjiang. PCR was employed for cloning 2 gene fragments, 12S rRNA and CO1 for analysis of phylogenetic diversity of E. granulosus. The results showed that all the samples collected were identified as G1 genotype of E. granulosus. Interestingly, YL5 and CJ75 strains were the older branches compared to those strains from France, Argentina, Australia. CO1 gene fragment showed 20 new genotype haploids and 5 new genotype haplogroups (H1-H5) by the analysis of Network 5.0 software, and the YLY17 strain was identified as the most ancestral haplotype. The major haplotypes, such as CJ75 and YL5 strains, showed identical to the isolates from Middle East. The international and domestic trade of livestock might contribute to the dispersal of different haplotypes for E. granulosus evolution.

• Journal of Life Science
• /
• v.19 no.10
• /
• pp.1451-1455
• /
• 2009

Porcine cytomegalovirus (PCMV) is a betaherpesvirus which causes reproductive failure in breeding sows and generalized infection in newborn piglets. It has worldwide distribution including Korea. Serological survey on this virus has been reported in 76.3% of pigs, but virological survey and epidemiological analysis on PCMV distribution have been reported in only a few papers in Korea. In this study, we investigated the virological prevalence and infection status of PCMV on a farm level in selected swine farms with respiratory diseases. A total of 1,938 blood samples taken from groups of pigs of different ages were collected from 31 farms distributed nationwide in 2006 and 2007 and tested by PCR to detect the presence of PCMV. Virological prevalence at farm level and pig level were 96.8% and 17.5%, respectively, suggesting that PCMV has endemically infected Korean pig herds. The prevalence at farm level in gilts, sows and suckling piglet groups were 16.7%, 36.7% and 56.7%, indicating that vertical infections frequently occurred in conception or newborn stage. Thereafter, detection rates of PCMV were slightly increased in pig groups aged 40 and 70 days (70.0% and 73.3%), and then gradually decreased as they aged - 33.3% in 100, 26.7% in 130 and 16.7% in 160 day old pig groups. The prevalence at pig level has similar patterns to that at farm level. With the passage of time, the variation of infection patterns of PCMV was investigated in four PCMV-positive farms. Three blood samples were collected at intervals of 6 months in each farm, and examined for presence of PCMV using PCR. The results revealed that once PCMV was introduced to the pig farms, it continuously circulated between and within groups of sows and piglets in those farms. Taken together, it can be concluded that PCMV has endemically infected Korean pig farms and has the potential risk for emerging pathogen in combination with the known endemic pathogens including porcine reproductive, respiratory syndrome virus and porcine circovirus type 2. Therefore, more research is needed on diagnosis, epidemiology and control strategy for PCMV on the field.