• Proceedings of the Korea Water Resources Association Conference
• /
• 2016.05a
• /
• pp.432-432
• /
• 2016

말라리아는 Plasmodium 속 원충으로 인하여 적혈구와 간 세포내에 발병하는 감염병으로, 매년 약 3-5억의 발병과 100만 명 이상의 사망자로 인하여 세계보건기구(WHO)가 선정한 6대 열대병 중에서도 가장 중요한 질환으로 고려되고 있다. 우리나라에서도 법정전염병 제3군으로 지정된 중요한 감염병이다. 국내에서는 지난 2000년 이후 감소 추세를 보이던 국내 말라리아 환자발생(현역 군인 포함)이 2005년 1,324명, 2006년 2,021명, 2007년 2,192명으로 2007년 국내 말라리아 환자는 전년대비 8.5%의 증가를 보이고 있다. 일반적으로, 매개체를 통한 감염병은 생태계 내에서의 상호 작용에 영향을 받기 때문 기후 인자와도 큰 영향을 받는 것으로 알려져 있다. 특히, 모기 매개 질병은 기후의 영향을 크게 받으며, 기온, 강수량, 습도 등의 수문기상 요소가 중요한 영향을 미치며, 그 중에서도 말라리아는 매개체에 의한 전염병 중 가장 중요하게 다루어지는 전염병인 동시에 기후변화에 가장 민감한 질병이다. 이 때문에 말리리아와 기후 인자 및 기후변화를 연관 지으려는 연구가 다수 수행되어 왔으며, 특히 최근에는 습지와 기후 인자와 말라리아의 상관관계를 분석하는 등의 다각적인 분석도 이루어지고 있다. 또한, 최근에 기후변화가 현실적인 문제로서 부각되면서 말라리아의 발생 문제에 대한 연구도 다각적으로 수행되고 있다. 본 연구에서는 기후 인자 및 기후변화와 상관성이 높은 감염병 중에서 국내 발병자 수가 많아서 분석이 용이한 말라리아를 주요한 감염병으로 선정하고, 말라리아의 발생과 기후 인자와의 상관관계를 살펴보고, 이를 바탕으로 기후 인자에 따른 말라리아의 발생을 모의할 수 있는 모형을 구축하고, 실제 적용성을 검증하였다. 이를 위하여 2001년부터 2011년까지의 월간 말라리아 감염병 발생 현황과 전국 기상대의 기후인자를 수집하였다. 말라리아와의 상관 분석을 위해서 포함된 기후인자는 평균기온($^{\circ}C$), 상대습도(%), 강수량(mm)을 이용하여 연관성을 분석하였으며, 이를 회귀 모형화 하였다. 연구결과, 구축된 회귀 모형이 말라리아 발생자료에 대한 설명력이 있는 것으로 나타났다.

• Parasites, Hosts and Diseases
• /
• v.23 no.2
• /
• pp.305-312
• /
• 1985

The surface fine structures of Ixodes persulcatus (Schulze, 1930) male and female specimens were observed by means of a scanning electron microscope. A brief review on the biology of the ticks and their disease relationships was also presented. 1. The sexual dimorphism of the specimen was marked; the male was quite smaller than the female. 2. The genital groove was well developed and deep, the anal groove was distinct and characteristically extending anteriorly around the anus. 3. The 4th article was much reduced and situated on the top of the 3rd article ventrally. The hypostome dentition was usually 3/3. 4. The bottom of the basis capitulum of the male specimen was strictly straight in shape. 5. This species was regarded as one of the most important vectors for infectious diseases of migrating birds.

• 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.36 no.3
• /
• pp.203-206
• /
• 1998

Two-day-old commercial chicks were inoculated orally with 2 × 106 oocysts of Cwptosporinium bailevi and vaccinated with 103.5 EID50/head of a commercially available avian infectious bronchitis (IB) live virus vaccine at 4 and 14 days following inoculation. Chicks infected with C. baileyi were shown to have an immunosuppressive effect on IB virus. It is concluded that infection with the protozoon in early life may increase their susceptibility to IB.

• Parasites, Hosts and Diseases
• /
• v.28 no.1
• /
• pp.45-52
• /
• 1990

Intestinal histopathological changes due to infection with Echinostcma hortense (Trematoda) were studied in rats after experimental infection with the metacercariae. The metacercariae were obtained from the tadpoles of Rana nigrcmaculata, a second intermediate host infected in the laboratory. Total 18 albino rats(Sprague-Dawley) were given 200 matacercariae each and sacrificed on the day 1, 3, 7, 11, 22 or 44 post-infection(PI) Segments of- the small intestine at 1, 3, 5, 8 and 30 cm posterior to the pylorus(PTP) were rejected and studied histopathologically. 1. The flukes were seen to have intruded into the intervillous space in the upper small intestine at early stages(1∼3 days PI), however, they were located mainly in the intestinal lumen at later stages(7∼44 days PI) . The flukes were sucking and destroying the epithelial layers of villi with their oral and ventral suckers. 2. Histopathological changes of the intestine were recognizable in as early as 1∼3 days after infection, and the changes became severer as the infection progressed. 3. The intestinal mucosa was histopathologically characterized by villous atrophy and crypt hyperplasia throughout the infection period. Major villous changes were blunting, fusion, severe destruction and loss of epithelial layers of villi. Villous/crypt(V/C) height ratio was remarkably reduced from 3 : 1 in controls to 1 : 1 in severely infected animals. In the stroma of villi, inaamma- tory cell infiltrations, vascular congestion, edema, and/or fibrosis were recognized. The goblet cells were increased in number after 11 days PI. It was revealed in the present study that the pathological changes in the intestine of rats infected with E. hortense were chieay confined to the mucosal layer of the upper small intestine, however, the changes were very severe accompanying remarkable destruction of villi and loss of mucosal integrity, and persistent until 44 days PI.

• Parasites, Hosts and Diseases
• /
• v.28 no.1
• /
• pp.1-10
• /
• 1990

To establish an animal model of intracranial sparganosis, the fate and behavior of the experimentally inoculated spargana were observed. A total of 102 scolices of spargana were injected into 22 cat brains, and the cats were sacrificed at 2 weeks, 1 month, 3 months and 6 months after the inoculation. Neurosparganosis was established in 77% of the cats. Of 43 recovered worms,19 (44%) were located in the subdural or subarachnoid space,16 (37%) in the brain Parenchyme, and 2 (5%) in the lateral ventricle. One was detected at the diploic space of the skull and 5 were outside the cranial cavity. All but one were alive, and had grown tails. They were distributed in the brain parenchyme randomly. There was no place which they could not invade. No adult was found in the intestine. Cerebrospinal fluid (CSF) was collected before inoculation, 1 week, 2 weeks, 1 month, 3 months and 6 months after inoculation. The level of anti-sparganum IgG antibody in CSF measured by ELISA began to increase above the criteria of positivity 1 month after inoculation. Three months after inocula- tion, the values markedly increased. The present findings reveal that intracranial inoculation of spargana into the brains of cats would be a good animal model of experimental neurosparganosis.

• Parasites, Hosts and Diseases
• /
• v.29 no.2
• /
• pp.181-188
• /
• 1991

Epidemiological studies on host rodents of tsutsugamushi disease were carried out during the period of July∼September 1990 at nine localities of central Korea. Among total 111 wild rodents trapped by the modified Sherman live traps, 103 were Apodemus agrarius (92.8%), seven were Crocidura lasiura (6.3%) and one was Microtus fortis (0.9%) , showing 24.0% of trapping rate in winter, 11.7% in spring, 11,2% in summer and 12.0% in autumn. Out of 103 A. agrarius 84 were parasitized by chiggers, showing 81.6% of the infestation rate and 43.0 of the chigger index. The antibody positive rate of A. agrarius sera to Rickettsia tsutsugamushi was significantly variable by locality, being in the range of 0∼78.6%. The seasonal change of the antibody positive rate at Dorai 5-ri, Goyang-gun was 75.8% in average during November∼March, decreased to 30.3% in April and further decreased to 13.3% in average during May∼August. Among 33 antibody positives, 31 were Karp strain and two were Gilliam. Seven Crocidura lasiura sera showed all negative. R. tsutsugamushi organisms were isolated from three A. ngrarius out of 94 mice tested, showing 3.2% of the infection rate.

• Parasites, Hosts and Diseases
• /
• v.33 no.3
• /
• pp.179-186
• /
• 1995

Human anisakiasis may occur after ingestion of raw marine flesh infected with nematode larvae of Anlsi,hidae. Anisakiasis caused by the migration of the larva into the wall of stomach, small intestine and other portion has been reported in Korea. This prospective study was made of all cases referred to parasitological laboratory in Cheju-do between. Tune 1989 and June 1992. Gastric anisakiasis was confirmed if larvae invading the gastric wall were observed by gastrofiberscopy One hundred and seven cases were diagnosed, most of which were in 30-49 years old. Most of the patients complained acute epigastric pain with history of eating raw marine fish. This symptom usually occurred about 12 hours to 1 day after ingestion of infected marine fish. Edema, erosion or ulcer of the mucosa and hemorrhage from the gastric wall were observed in the involved areas. Ninety larvae removed from the stomach were identified; the larva of Anisqkis siwlex was the most prevalent species, and the Iarva of Pseudntewanoua decipien was also detected. The important species of marine fish from which the patients became infected was demonstrated as yellow corvina, sea eel, ling, cuttle fish, yellowtail and others. Five species of marine fish as a possible source of infection were examined, and Anisakis simplex larvae and Pseunotewqnoua decipirens larvae were collected from the mackerel and rock cod. This study demonstrates that anisakiasis is recognized as a public health problem in Korea.

• Parasites, Hosts and Diseases
• /
• v.27 no.4
• /
• pp.261-270
• /
• 1989

The present study is intended to observe the chronologic changes of experimental sparganosis by histopathological observation and detection of circulating anti-sparganum IgG antibody using ELISA. Each of 25 mice was infected with aye spargana, and they were examined after 1, 2, 4, 10 weeks or 6 months from infection. The followings are summarized results. - 1. The plerocercoids were detected in the subcutaneous tissue of the trunk, neck or axilla, but a few often extended into the skeletal muscle. The recovery rates were 72% at the first week, 80% at the second week, 95% at the fourth week, 92% at the tenth week and 100% at .the sixth month. The larvae grew slowly in both length and weight until 6 months. 2. Histopathologically, most of the larvae were observed alive in the soft tissue or skeletal muscle. Numerous eosinophils, neutrophils, Iymphocytes and plasma cells were infiltrated focally around the worms by the second week, but they surrounded the worms to form a layer of inflammatory reaction after 4 weeks of infection. Also histiocytes and fibroblasts began to appear around the inflammatory cells at 4 weeks. After 10 weeks, the worms encircled by a thin fibrous layer were found. After 6 months, the worms were surrounded by either fibrous tissue or active inflammatory cells. The inflammation looked more severe in the tracks left by the worms, rather than around the worms. 3, The level of anti-sparganum IgG antibody in the serum showed an increase by the fourth week, and a rapid and continuous increase was observed thereafter by the tenth week after infection. The high level of the IgG antibody was maintained up to 6 months forming a plateau curve. The present results suggest that the tissue reaction and antibody production in subcutaneous sparganosis become distinctive by the fourth week after infection.

• Parasites, Hosts and Diseases
• /
• v.28 no.3
• /
• pp.183-194
• /
• 1990

In an attempt to develop prophylactic and therapeutic measures of the intestinal giant-cystic disease caused by Thelohanellus kitauei in the Israel carp, Cyprinus carpio nodus, pathological observations were conducted upon the carps which were hatched in May 1988 and raised in a net cage fish farm at the Soyang lake, managed by Horim Fisheries for the period of 21 months with 1~2 months interval. After a gross inspection of the carps, necropsy was carried out periodically in order to clarify the pathological changes in various internal organs and muscular tissues. Also. the prevalence of the disease was checked during the period from 1988 to 1990. Gross inspections revealed that the infected carps showed some degree of fading in body and gill color, back-emaciation symptoms, reddish anus accompanying erosion and relaxation and pot-belly, as well as discharge of yellowish white mucoid material from the anus. However, most carps died eventually of intestinal obstruction. Other significant necropsy fadings included cyst formation of various size in the intestinal mucosa, ascites, anemic condition through internal organs and muscular tissues, hyperemia and dilation of intestines with decreased tension, thinness and fragility, and full contents of semi-fluid or yellowish white mucoid material in the intestinal canals. Based on the morphological characteristics of the spores found in the cysts, parasitic location in the intestines, macro- and microscopic findings of the lesions, the parasites were identised as Thelohanellus kitauei Egusa os Nakajima, 1981. Although monthly changes of water temperature were distinct, the extrusion rates of the polar filaments of the spores stayed constant throughout the year with an exception of a lower rate in July, The lesions initiated from mucosa and submucosa in early July became large swellings and then complete mature (orms following the peracute course. From late August the upper cysts were gradually opened and most of the spores were dispersed from anus into the surrounding water through December but only a few lasted until next April. The cysts were completely recovered until next September. Comparing the incidence and prevalence of the disease by year tremendous infection and death rates were checked in the first prevalent year, 1988, but the rates were significantly decreased in the second year, and showed an almost normal status in the third year, 1990. As the above summarized results showed, the disease entity might come to an end in three years after the first prevalent year, however, the spores must be strictly prevented because they could be infective in the water for one year.