Epidemiologic evaluation of pulmonary paragonimiasis in Japan using a Japanese nationwide administrative database.

BACKGROUND: Paragonimiasis is a parasitic disease primarily contracted through consumption of undercooked freshwater crustaceans or wild boar meat. Large-scale nationwide epidemiological data on paragonimiasis are lacking. In this study, we aimed to investigate the nationwide epidemiology of hospitalized patients with paragonimiasis in Japan using a comprehensive nationwide Japanese administrative database. METHODS: We evaluated the Japanese Diagnosis Procedure Combination (DPC) data of patients diagnosed with pulmonary paragonimiasis between April 1, 2012 and March 30, 2020. The patients' address and information, including age, sex, treatment (medication: praziquantel; surgery: open thoracotomy or intracranial mass extirpation), Japan coma scale, comorbidities, and length of hospital stay, were extracted. RESULTS: Of the 49.6 million hospitalized patients, data were extracted on 73 patients with paragonimiasis, of whom 36 were male and 37 were female. The mean age was 49.7 years and the mean length of stay was 12.5 days. The most frequent comorbidity was pleural effusion (31.5 %), followed by pneumothorax (13.7 %). The sites of ectopic paragonimiasis in organs other than the lung included the liver (5.5 %), skin (4.1 %), and brain (2.7 %). Geographically, most patients were from the Kyushu region (54.8 %), followed by the Kanto region (22.0 %). Fukuoka Prefecture had the highest number of patients (22.0 %) by prefecture. During the study period, an average of 9.1 patients/year were hospitalized with lung paragonimiasis in Japan. CONCLUSION: Paragonimiasis has not completely disappeared in Japan; thus, physicians should be aware of paragonimiasis in the Kyushu region, especially in the Fukuoka Prefecture.

Pulmonary, liver and cerebral paragonimiasis: An unusual clinical case in Colombia.

BACKGROUND: Mainly affecting poorer populations in remote (sub)tropical areas, paragonimiasis is considered one of the world's most neglected tropical diseases by the World Health Organization. It is usually acquired by consuming undercooked freshwater crustaceans and primarily affects the lungs, but may ectopically migrate to other organs to produce a multisystemic clinical presentation. This study details what appears to be the first documented case in South America and particularly in Colombia of cerebral paragonimiasis and infection by the crab Moreirocarcinus emarginatus. CASE PRESENTATION: After consuming this crab, a 32-year-old Colombian male developed dyspnea and headache. A chest X-ray revealed tension pneumothorax (TPT) and a thoracoscopic lung biopsy bronchiolitis, eosinophilia, and granulomatous reaction due to Paragonimus parasites. RESULTS: Brain tomography and MRI also showed a configuration typical of Paragonimus parasites, namely a predominantly cystic area near the left cuneus with diffusion restriction, a hemosiderin halo, and linear enhancement characteristic of the tunnel sign, indicating an adult worm moving in the brain. CONCLUSIONS: Cerebral paragonimiasis can occur in the Colombian population and Moreirocarcinus emarginatus can be its cause. In rural areas, education about raw crab consumption would be beneficial, and physicians addressing lung-related complaints should bear paragonimiasis in mind and ask about raw crab consumption.

A retrospective clinical analysis of pediatric paragonimiasis in a Chinese children's hospital from 2011 to 2019.

Diagnosis of pediatric paragonimiasis is difficult because of its non-specific clinical manifestations. We retrospectively reviewed the records of pediatric paragonimiasis in Children's Hospital of Fudan University from January 2011 to May 2019. The confirmed diagnosis of paragonimiasis was based on positive anti-parasite serological tests from the local Center for Disease Control (CDC). A total of 11 patients (mean age: 7.7 ± 3.1, male-female ratio: 7:4) diagnosed as paragonimiasis were included. 81.8% were from endemic areas such as Sichuan and Yunnan, and 36% had a clear history of raw crab or crayfish consumption. The characteristic clinical features of pediatric paragonimiasis were eosinophilia (100%), pleural effusion (81.8%), hepatomegaly (54.5%), ascites (54.5%), and subcutaneous nodules (45.5%). Misdiagnosed with other diseases including tuberculosis (18.2%), pneumonia (9.1%), intracranial space-occupying lesions (9.1%) and brain abcess (9.1%) led to rehospitalization and prolonged hospitalization. For treatment, a 3-day course of 150 mg/kg praziquantel (PZQ) didn't show ideal treatment effectivity and 63.6% needed more than one course of PZQ, while triclabendazole in a total dose of 10 mg/kg had a better efficacy to stubborn manifestations. This study indicated that pediatric paragonimiasis was often misdiagnosed, and the treatment with a 3-day course of 150 mg/kg PZQ had a high rate of failure.

[Investigation on freshwater crab populations and Paragonimus infections in the Minjiang River basin along the middle section of Wuyi Mountain].

OBJECTIVE: To investigate the populations of freshwater crabs, the intermediate host of Paragonimus and Paragonimus infections in freshwater crabs in the Minjiang River basin along the middle section of Wuyi Mountain, so as to provide baseline data for parasitic disease control and research and expansion of the parasite resource bank. METHODS: From November 2020 to April 2021, freshwater crabs were sampled from streams and ditches neighboring residential areas in Jianning County and its neighboring Ninghua, Shaowu, Jiangle and Shunchang counties. The crab species was identified based on the morphological features of the terminal segment of the first abdominal appendage of male crabs, and Paragonimus infections were detected in freshwater crabs. The Paragonimus metacercariae were isolated, and the types of metacercariae were identified based on the metacercaria size, cystic wall thickness, and the excretory bladder and intestinal tract morphology. In addition, the prevalence, intensity and index of metacercaria infections were calculated in freshwater crabs. RESULTS: There were seven crab species found in Jianning County and six neighboring water systems along the Minjiang River basin, including Sinopotamon jianglense, S. fukinense, Huananpotamon lichuanense, H. lini, H. shenni, H. planopodum, Bottapotamon engelhardti, and there were metacercariae of three Paragonimus species detected in these crabs, including P. westermani, P. skrjabini and P. sanpingensis, with a prevalence rate of 43.6% (125/287). The infection rates of P. westermani, P. sanpingensis and P. skrjabini were 57.1% (48/84), 26.2% (22/84) and 61.8% (21/34) in S. jianglense, and the infection rates of P. westermani and P. sanpingensis were 52.6% (51/97) and 30.9% (30/97) in S. fukinense, while the rate of P. westermani infection was 6.9% (5/72) in H. lichuanense, which is the first record of P. westermani infections in H. lichuanense. Mixed P. westermani and P. sanpingensis infections were predominantly found in freshwater crabs sampled from Jianning County, where the rate of Paragonimus infections was 70.4% (76/108), with 15.3 metacercariae identified in each crab with Paragonimus infections and 1.9 metacercariae found in each gram of crabs with Paragonimus infections, and the index of metacercariae infections was 20.5. In addition, P. westermani, P. skrjabini and P. sanpingensi metacercariae were found in freshwater crabs sampled from Jianning-neighboring counties, where the rate of Paragonimus infections was 52.3% (56/107), with 9.8 metacercariae identified in each crab with Paragonimus infections and 0.9 metacercariae found in each gram of crabs with Paragonimus infections, and the index of metacercariae infections was 4.6. CONCLUSIONS: There are multiple freshwater crab species and Paragonimus infection is high in freshwater crabs in Jianning County and its neighboring Minjiang River basin, which is a high-risk natural focus for Paragonimus infections.

Spectrum of pleuropulmonary paragonimiasis: An analysis of 685 cases diagnosed over 22 years.

OBJECTIVES: Paragonimiasis is a global foodborne zoonosis. Overlapping clinical and imaging features with other lung pathologies hamper correct diagnosis and require differential diagnosis. METHODS: During 1982-2003, 49,012 samples were referred for immunodiagnosis of helminthiases. We detected paragonimiasis cases by enzyme-linked immunosorbent assay (ELISA). We assessed clinical, radiographical and laboratory characteristics, and diagnostic dilemmas associated with delayed diagnosis. RESULTS: We analyzed 685 pleuropulmonary paragonimiasis cases. ELISA-positive was 665. Eggs were detected in 50. Symptom duration correlated well with the appearance of chest radiographs; 359 pleural, 33 pleuroparenchymal, and 264 parenchymal lesions (P < 0.001). Twenty-nine had normal chest images. Eosinophilia, seen in 304, was common in pleural and pleuroparenchymal patients (P < 0.05). Chest pain and dyspnea were characteristic for pleurisy patients. Sputum (odds ratios [OR]: 6.79; 95% CI: 4.41-10.47), blood-tinged sputum (OR: 5.62; 95% CI: 3.75-8.42), and foul-odor (OR: 2.70; 95% CI: 1.42-5.16) were significant in parenchymal patients. Delayed diagnosis (119) for ≥ 25 weeks was attributed mainly to misdiagnosis as tuberculosis, malignancy, or chronic obstructive pulmonary disease (COPD) (OR: 111.75; 95% CI: 43.25-288.74). CONCLUSIONS: Variable symptoms and radiographs of pleuropulmonary paragonimiasis depended on the stage of infection. Suspicion of tuberculosis, malignancy, or COPD was major cause of delayed diagnosis.

Paragonimus and paragonimiasis in Asia: An update.

Paragonimiasis, or lung fluke disease, is a typical food-borne parasitic zoonosis caused by infection with trematodes belonging to the genus Paragonimus. More than 50 species of Paragonimus have been reported throughout the world, of which seven valid species infect humans, an estimated one million people annually worldwide. Among the seven species, P. westermani, P. heterotremus, and P. skrjabini/P. s. miyazakii, distributed in Asia, are the most important species as the cause of paragonimiasis. Humans acquire infection through the ingestion of raw, pickled or undercooked freshwater crustaceans, 2nd intermediate hosts, or consuming raw meat of wild boar or deer, paratenic hosts. Infections often occur clustered in foci where dietary habits allow transmission of the parasites. Paragonimiasis typically causes a subacute to chronic inflammatory disease of the lungs. The symptoms, including chronic cough, chest pain, dyspnea and hemoptysis, mimic those of tuberculosis and lung cancer. Serologic tests are commonly used for the diagnosis of paragonimiasis, and Praziquantel is the treatment of choice. In this review, the current status of Paragonimus and paragonimiasis in Asia is outlined based on the latest information and findings. We also summarize current trends of paragonimiasis in Japan, which is one of the most endemic area of paragonimiasis in the world, for the better understanding and control of paragonimiasis.

Paragonimiasis in Children in Southwest China: A retrospective case reports review from 2005 to 2016.

BACKGROUND: Paragonimiasis infection has no specific symptoms or typical radiologic findings, leading to the possibility of misdiagnosis. Thus, the objective of this study was to analyze clinical and radiological features, and treatment outcome of paragonimiasis in children in Southwest China to improve the awareness of this disease. METHODS: We retrospectively reviewed the records of children diagnosed with paragonimiasis in West China Second University Hospital between 2005 and 2016. The confirmed diagnosis of paragonimiasis was based on epidemiology history and seropositivity for paragonimiasis and/or detection of paragonimus eggs. Clinical, laboratory, and imaging findings of patients were examined in order to summarize risk factors, clinical characteristics, and treatment outcomes of these patients. RESULTS: A total of 123 patients were included; of them 112 (91.1%) lived in villages and 72 (58.5%) had a history of consuming freshwater crabs. Patients with paragonimiasis most frequently showed respiratory symptoms, including cough (26.0%, 32/123) and tachypnea (16.3%, 20/123), and gastrointestinal symptoms, including abdominal pain (26.8%, 33/123), abdominal distention (22.8%, 28/123), and vomiting (13.0%, 16/123). Laboratory examination showed elevated white blood cell (WBC) counts in the peripheral blood in 89 (72.4%) patients and eosinophilia in 102 (82.9%) patients. Tuberculosis (TB) coinfection was found in 4 (3.3%) patients. Main imaging findings included: effusions (90.4%), lymphadenopathy (40.4%), pulmonary ground-glass opacities (36.2%), cystic lesions (18.1%), and pleural thickening (17.0%). Twenty-nine patients (23.6%) received more than 1 course of praziquantel (PZQ). Additionally, 4 (19.0%) of 21 patients who were discharged from the hospital without complete treatment required rehospitalization for residual serous effusions. Moreover, patients from pericardial effusion group showed longer hospital stays and less elevated WBC counts than those from nonpericardial effusion group. CONCLUSION: Paragonimiasis should be considered in patients from endemic areas, especially in those with gastrointestinal and/or respiratory symptoms, elevated WBC count, eosinophilia, and serous effusions. Additionally, longer hospital stay may be necessary in cases of paragonimiasis associated with pericardial effusions.

Significance of Serology by Multi-Antigen ELISA for Tissue Helminthiases in Korea.

It is clinically important to differentiate tissue-invading helminthiasis. The purpose of this study was to assess the specific immunoglobulin G (IgG) antibody positive rates for clonorchiasis, paragonimiasis, cysticercosis, and sparganosis 4 helminthiases from 1996 to 2006 using multi-antigen enzyme-linked immunosorbent assay (ELISA) in Korea. Results of 6,017 samples, which were referred to our institute for serodiagnosis, were analyzed. The subjects with positive serum IgG antibodies were 1,502 (25.0%) for any of the 4 helminthiases. The overall positive numbers for clonorchiasis, paragonimiasis, cysticercosis, and sparganosis were 728 (12.1%), 166 (2.8%), 729 (12.1%), and 263 (4.4%), respectively. The positive serologic reaction to multi-antigens was determined in 309 (20.6%) of the 1,502 total seropositive subjects. Those with multi-antigen positivity were regarded as positive for the antigen of strongest reaction but cross-reaction to others with weak positive reaction. Annual seropositive rates for those 4 tissue helminthiases ranged from 12.1% to 35.7%. The highest rate was observed in age from 60 to 69 years old and prevalence of men (27.4%; 1,030/3,763) was significantly higher than of women (19.1%; 332/1,741). Hospital records of 165 ELISA positive patients were reviewed to confirm correlation with their clinical diagnosis. Paragonimiasis was highly correlated as 81.8% (9/11), cysticercosis 29.9% (20/67), clonorchiasis 29.0% (20/69), and sparganosis 11.1% (2/18). In conclusion, the multi-antigen ELISA using 4 helminth antigens is useful to differentiate suspected tissue-invading helminthiases, especially ELISA diagnosis of paragonimiasis is reliable. The seropositivity is still high among suspected patients in Korea.

Morphological and molecular characterization of the metacercaria of Paragonimus caliensis, as a separate species from P. mexicanus in Costa Rica.

The trematode Paragonimus mexicanus is the etiological agent of paragonimiasis, a food-borne zoonotic disease in Latin America. This species, as well as Paragonimus caliensis, have been reported from Costa Rica, but it is not known if the two are synonymous. Two types of Paragonimus metacercariae from freshwater pseudothelphusid crabs from several localities in Costa Rica were recognized by light microscopy. Morphologically, these corresponded to descriptions of P. mexicanus and P. caliensis. Metacercariae of the former species lacked a membrane or cyst and their bodies were yellow in color. Those of P. caliensis were contained in a transparent thin cyst and were pink in color. Morphotypes of metacercariae were determined using scanning electron microscopy (SEM). Based on the number and distribution of papillae in the ventral sucker, three morphotypes were found for P. mexicanus and two for P. caliensis. Analysis of DNA sequences (nuclear ribosomal 28S and ITS2 genes, and partial mitochondrial cox1 gene) confirmed the presence of P. mexicanus and provided the first molecular data for P. caliensis. The two species are phylogenetically distinct from each other and distant from the Asian species. The confirmation of P. caliensis as a separate species from P. mexicanus raises several questions about the ecology, biological diversity, and epidemiology of the genus Paragonimus in Costa Rica.

Severe Pleuropulmonary Paragonimiasis Caused by Paragonimus mexicanus Treated as Tuberculosis in Ecuador.

A 30-year-old male, from a subtropical region of Ecuador, was hospitalized with a 5-year history of persistent cough with rusty brown sputum, chest pain, and progressive dyspnea. The patient underwent thoracic surgery 3 years ago for pleural effusion and subsequently received a 9-month regimen treatment of tuberculosis. However, there was no clinical resolution and symptoms became progressively worse. A chest radiograph and computerized tomography scan showed several small nodules in both lungs. Eggs of Paragonimus spp. were observed in sputum smears, but the smears were negative for acid-fast bacilli. Molecular characterization of eggs by the internal transcribed spacer-2 regions identified them as Paragonimus mexicanus The patient was treated with praziquantel and tested negative parasitologically for 12 months. There was clinical resolution of the cough and expectoration, but dyspnea and chest pain persisted.

North American paragonimiasis: epidemiology and diagnostic strategies.

Paragonimiasis is a zoonotic, food-borne trematode infection that affects around 23 million people in Asia, Africa and the Americas. North American paragonimiasis, caused by Paragonimus kellicotti, is a common infection of crustacean-feeding mammals in parts of the USA and Canada. Although infection rates in crayfish are very high in some areas, human infections are rare and depend on the consumption of raw or undercooked crayfish. Human infections can be easily prevented and treated, but proper diagnosis of paragonimiasis is a problem. Paragonimus lung flukes often cause serious disease symptoms before they produce eggs that may be detectable in sputum, bronchoalveolar lavage, stool or histological sections by microscopy or PCR. Antibodies against selected Paragonimus proteins are detectable as early as 2-3 weeks after infection. Therefore, antibody serology is the most promising diagnostic approach for paragonimiasis in North America and elsewhere.

Current status of Paragonimus and paragonimiasis in Ecuador

A review of national and international publications on paragonimiasis in Ecuador, epidemiological records from the Ministry of Public Health and unpublished research data was conducted to summarise the current status of the parasite/disease. The purpose of the review is to educate physicians, policy-makers and health providers on the status of the disease and to stimulate scientific investigators to conduct further research. Paragonimiasis was first diagnosed in Ecuador 94 years ago and it is endemic to both tropical and subtropical regions in 19 of 24 provinces in the Pacific Coast and Amazon regions. Paragonimus mexicanus is the only known species in the country, with the mollusc Aroapyrgus colombiensis and the crabs Moreirocarcinus emarginatus, Hypolobocera chilensis and Hypolobocera aequatorialis being the primary and secondary intermediate hosts, respectively. Recent studies found P. mexicanus metacercariae in Trichodactylus faxoni crabs of the northern Amazon. Chronic pulmonary paragonimiasis is commonly misdiagnosed and treated as tuberculosis and although studies have demonstrated the efficacy of praziquantel and triclabendazole for the treatment of human infections, neither drug is available in Ecuador. Official data recorded from 1978-2007 indicate an annual incidence of 85.5 cases throughout the 19 provinces, with an estimated 17.2% of the population at risk of infection. There are no current data on the incidence/prevalence of infection, nor is there a national control programme.

Serological diagnosis of North American Paragonimiasis by Western blot using Paragonimus kellicotti adult worm antigen.

Abstract. We studied the value of an IgG Western blot (WB) with Paragonimus kellicotti (Pk) antigen for diagnosis of North American paragonimiasis. The test was evaluated with sera from patients with Pk and Paragonimus westermani infections, with control sera from patients with other helminth infections, and sera from healthy Americans. All 11 proven Pk infection sera and two samples from suspected cases that were negative by P. westermani WB at the Centers for Disease Control and Prevention (CDC) contained antibodies to antigens at 34 kDa and at 21/23 kDa. Seven of 7 P. westermani sera contained antibodies to the 34 kDa antigen, but only 2 recognized the 21/23 kDa doublet. No control samples were reactive with these antigens. Antibody reactivity declined after praziquantel treatment. Thus, the P. kellicotti WB appears to be superior to P. westermani WB for diagnosing Pk infections, and it may be useful for assessing responses to treatment.

Paragonimus kellicotti flukes in Missouri, USA.

Paragonimiasis is an infection caused by lung flukes of the genus Paragonimus. In Asia, P. westermani infections are relatively common because of dietary practices. However, in North America, cases of paragonimiasis, which are caused by P. kellicotti flukes, are rare. Only 7 autochthonous cases of paragonimiasis were reported during 1968-2008. In 2009, we reported 3 new case-patients with paragonimiasis who had been seen at our medical center over an 18-month period. Six additional case-patients were identified in St. Louis, Missouri, USA, and treated at Washington University-affiliated health centers in 2009-2010. We report detailed descriptions of these case-patients, which includes unusual clinical manifestations. We also describe public health interventions that were undertaken to inform the general public and physicians about the disease and its mode of transmission.

Boil before eating: paragonimiasis after eating raw crayfish in the Mississippi River Basin.

Paragonimiasis is a parasitic infection of the lungs caused by zoonotic lung flukes of the genus Paragonimus. Most cases are reported from Asia and caused by P. westermani following consumption of raw crustaceans. With the exception of imported cases, human paragonimiasis was rarely described prior to 1984 in the United States (US), which has only one indigenous lung fluke species, P. kellicotti. Between 1984 and 2010, 15 cases of P. kellicotti paragonimiasis were reported in the United States. This study will analyze all US cases and compare an earlier series of six cases reported during the period 1984-2005 with a recently reported cluster of nine cases from Missouri during the period 2006-2010 in order to determine any significant behavioral and/ or recreational risk factors for paragonimiasis and to recommend early diagnostic, treatment and preventive strategies. Significant behavioral and recreational risk factors included eating raw crayfish while on canoeing trips on local rivers (p = 0.002), eating raw crayfish while on canoeing trips in Missouri (p = 0.002), and eating raw crayfish while intoxicated (p = 0.007). The male:female case ratio was 9.3:1.0 and more than 80% of cases presented with fever, cough, pleural effusions and peripheral eosinophilia. One patient developed cerebral paragonimiasis, and one patient died of pneumonic sepsis. Clinicians should inquire about consumption of raw or undercooked crayfish in all patients with unexplained fever, cough, eosinophilia and pleural effusions returning from camping or canoeing adventures in P. kellicotti-endemic areas of the Mississippi River Drainage Basin; institute diagnostic evaluation by specific parasitological and serological methods and treat all cases as soon as possible to avoid the pulmonary and cerebral complications of paragonimiasis.

Serological and molecular tools to detect neurologic parasitic zoonoses in rural Cameroon.

Parasitic helminthiases, such as toxocariasis, cysticercosis and paragonimiasis are a public health threat, since they can affect the brain leading to neurological disorders. Epilepsy and paragonimiasis are common in southwestern Cameroon. We reviewed the literature for studies using antigens to diagnose toxocariasis, cysticercosis, and paragonimiasis. Serology revealed that 61 (36.3%), 26 (15.5%) and 2 (1.2%) of 168 persons examined [78 males (15.2 +/- 8.2 years old), 90 females (12.9 +/- 5.9 years old), 143 persons < 20 years old] had antibody responses to toxocariasis, paragonimiasis and cysticercosis, respectively. Of the 14 people with epilepsy, 5 were seropositive for Toxocara antigens and 1 was positive for both Toxocara and Paragonimus antigens. Two children were serologically confirmed to have cysticercosis. Serologic screening for cysticercosis may be feasible to detect asymptomatic cysticercosis in children in endemic areas leading to early treatment. The causative Paragonimus species was confirmed to be P. africanus by molecular sequencing. Education, screening and confirmation test for these diseases may be needed for control in Cameroon.

Parasitic infections in foreigners living in Japan: estimation of parasitic infection history by serum antibody screening.

We recently surveyed parasitic infections in 334 foreigners living as permanent residents in Japan. The survey results are presented herein. Our results highlight open issues in Japan, with reference to measures taken in Western countries where immigrants have long been accepted. In addition, we present our epidemiological method for investigating parasitic infection, making use of simple and valid large-scale screening. Among the foreigners participating in this survey, parasitic infections other than those in toxoplasmosis antibody positive individuals were rare. However, in view of the recent trend for increased total numbers of foreigners living in Japan, the onset of parasitic infections is anticipated to increase in Japan henceforth.

Different chest radiographic findings of pulmonary paragonimiasis in two endemic countries.

We compared the chest radiographic findings of patients with pulmonary paragonimiasis in the Lao People's Democratic Republic (PDR) with a report from Korea. The clinical and radiological characteristics of 50 confirmed Laotian pleuropulmonary paragonimiasis patients were studied between March 2003 and June 2007. In 49 patients, the chest radiographs showed abnormal findings (98%). Pulmonary parenchymal abnormalities were found in all 49 patients, whereas pleural effusion was only found in 11 patients (22%). The three most common intraparenchymal findings were multiple small cysts (90%), irregular linear densities (68%), and nodular opacities (40%). The numbers of patients who had these three findings were significantly different from the Korean report (P < 0.001). In conclusion, radiographic findings of pulmonary paragonimiasis may vary among countries.

Seroprevalence of tissue invading parasitic infections diagnosed by ELISA in Korea.

Seroprevalence of the IgG antibodies for Clonorchis sinensis, Paragonimus westermani, Taenia solium metacestode (cysticercus), and Spirometra erinacei plerocercoid (sparganum) was measured using enzyme-linked immunosorbent assay (ELISA) in sera of patients in Korea from 1993 to 2006. A total of 74,448 specimens referred nationwide from 121 hospitals revealed an IgG positive rate of 7.6% for the 4 parasites. The IgG positive rate (18.7%) for the 4 parasites in 1993 decreased gradually to 6.6% in 2006. Individual positive rate decreased from 5.2% (1993) to 1.6% (2006) for C. sinensis, from 2.8% (1993) to 1.1% (2006) for P. westermani, from 8.3% (1993) to 2.2% (2006) for cysticercus, and from 2.6% (1993) to 1.6% (2006) for sparganum. The positive rate was highest (21.2%) in the group of patients who ranged in age from 50-59 yr old, and in the group that was referred from the Seoul area (55.9%). In conclusion, our results suggest that tissue invading parasitic infections should always be included in differential diagnosis for patients with eosinophilia associated lesions of the central nervous system, liver, and lungs in Korea.