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international publications on paragonimiasis in Ecuador, epidemiological records from the Ministry of Public Health and unpublished research data was conducted to summarise the current status of the parasite/disease.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.

Paragonimus and Paragonimiasis in Vietnam: an Update

Paragonimiasis is a food-borne parasitic zoonosis caused by infection with lung flukes of the genus Paragonimus. In Vietnam, research on Paragonimus and paragonimiasis has been conducted in northern and central regions of the country. Using a combination of morphological and molecular methods, 7 Paragonimus species, namely P. heterotremus, P. westermani, P. skrjabini, P. vietnamensis, P. proliferus, P. bangkokenis and P. harinasutai, have been identified in Vietnam. Of these, the first 3, P. heterotremus, P. westermani and P. skrjabini, are known to infect humans in other countries. However, in Vietnam, only P. heterotremus, found in some northern provinces, has been shown to infect humans. Even nowadays, local people in some northern provinces, such as Lai Chau and Yen Bai, are still suffering from P. heterotremus infection. In some provinces of central Vietnam, the prevalence and infection intensity of P. westermani metacercariae in freshwater crabs (the second intermediate hosts) are extremely high, but human cases have not been reported. Likewise, although P. skrjabini was found in Thanh Hoa Province, its pathogenicity to humans in Vietnam still remains uncertain. The results of molecular phylogenetic analyses of Vietnamese Paragonimus species provides new insights on the phylogeny and taxonomy of the genus Paragonimus. Comprehensive molecular epidemiological and geobiological studies on the genus in Vietnam and adjacent countries are needed to clarify the biodiversity and public health significance of the lung flukes.

Paragonimus & paragonimiasis in India.

Ever since the discovery of the first indigenous case in 1981, paragonimiasis has gained recognition as a significant food borne parasitic zoonosis in India. The data available on the occurrence of paragonimiasis, until today, may be just the tip of an iceberg as the study areas covered were restricted to Northeast Indian States. Nevertheless, the results of research on paragonimiasis in India have revealed valuable information in epidemiology, life cycle, pathobiology and speciation of Indian Paragonimus. Potamiscus manipurensis, Alcomon superciliosum and Maydelliathelphusa lugubris were identified as the crab hosts of Paragonimus. Paragonimus miyazakii manipurinus n. sub sp., P. hueit’ungensis, P. skrjabini, P. heterotremus, P. compactus, and P. westermani have been described from India. P. heterotremus was found as the causative agent of human paragonimiasis. Ingestion of undercooked crabs and raw crab extract was the major mode of infection. Pulmonary paragonimiasis was the commonest clinical manifestation while pleural effusion and subcutaneous nodules were the common extra-pulmonary forms. Clinico-radiological features of pulmonary paragonimiasis simulated pulmonary tuberculosis. Intradermal test, ELISA and Dot-immunogold filtration assay (DIGFA) were used for diagnosis and epidemiological survey of paragonimiasis. Phylogenitically, Indian Paragonimus species, although nested within the respective clade were distantly related to others within the clade.

Paragonimiasis pleuro pulmonar / Pleuropulmonary paragonimiasis

La paragonimiasis es una antropozoonosis de transmisión alimentaria causada por tremátodos del género Paragonimus siendo P. Westwermanii el que más infecta al hombre. La infección del humano ocurre posterior a la ingesta de crustáceos de agua dulce mal cocinados, infectados con metacercarias. La gravedad y la progresión de los síntomas dependen de la fase y del número de parásitos presentes. La fase de infección pulmonar está caracterizada por tos, hemoptisis, dolor torácico, pérdida de peso y anormalidades radiológicas. Dado la sintomatología respiratoria y los hallazgos radiológicos inespecíficos; la tuberculosis pulmonar es el principal diagnostico diferencial a considerar. El diagnóstico se basa en la demostración del paragonimus por medios parasitológicos, en algunos casos como paragonimiasis extra pulmonar o en otras circunstancias cuando los métodos bacteriológicos fallan es necesario la realización estudios serológicos. El prazicuantel actualmente es considerado el tratamiento de elección.

Epidemiology of Paragonimiasis in Oban Community of Cross River State; Nigeria

The epidemiology and perception of Paragonimus infection were investigated in Oban community of Cross River State; Nigeria between January and June; 2006. Sputum samples collected on each of three consecutive days from 311 participants with productive cough were examined using standard parasitological procedures for the detection of ova of Paragonimus Spp. The samples were also processed and stained using the Ziehl-Neelsen technique to exclude Mycobacterium tuberculosis infection. Crabs collected from the village streams were dissected and examined for the presence of metacercariae of Paragonimus Spp. A questionnaire was also administered to test the perception of the disease. Paragonimus uterobilateralis was confirmed as the aetiologic agent of paragonimiasis with a prevalence of 4.2. Peak prevalence of 7.7was found among children aged between 1 to 10 years. More males (4.5) were infected than females (3.9) (P 0.05). The mean egg count was high (222 egs/5ml of sputum). The intensity of infection was found to correlate moderately and strongly with haemoptysis (r = 0.6) and chest pain (r=0.8) respectively. Only 1.6of the subjects had tuberculosis and presented with symptoms which mimic paragonimiasis. Sudanonautes africanus is the suspected vector of the disease in this locality. The disease; its vector and mode of transmission were poorly perceived by the respondents. The study has confirmed the endemicity of paragonimiasis in Oban community as well as provides comprehensive information on the disease and its transmission in this locality. There is urgent need to initiate the control of this disease in this community

Infection Status of Freshwater Crabs and Crayfish with Metacercariae of Paragonimus westermani in Korea

The present study investigated the infection status of Paragonimus westermani metacercariae in freshwater crabs (n = 363) and crayfish (n = 31) from October 2007 to October 2008 using the crush method. All of the freshwater crabs, Eriocheir japonicus, were negative for P. westermani metacercariae while 10 (32.3%) of the 31 examined crayfish were positive. The 10 positive crayfish were caught in Haenam, Jeollanam-do, and there were 8-59 (mean 28.4) metacrcariae per infected crayfish. These results suggest that P. westermani metacerariae are still transmitted by crayfish enzootically in southern Korea, and that freshwater crabs may transmit metacercariae only on rare occasions.

Estudio de foco de paragonimosis en Fuente Clara, Robledo, área periurbana de Medellín, Antioquia / Paragonimosis in the peri-urban zone of Medellín, Antioquia

Introducción. La información sobre paragonimosis humana en Colombia llevó a suponer que los focos de la enfermedad estaban localizados en sectores selváticos; sin embargo, durante 2005 se hallaron cangrejos infectados con Paragonimus sp. en Fuente Clara, zona urbana de Medellín. Esto motivó la investigación. Objetivo. Realizar un estudio ecoepidemiológico de la paragonimosis con la participación de la comunidad para promover un manejo adecuado de los ecosistemas acuáticos. Materiales y métodos. Se realizó búsqueda de huéspedes silvestres y humanos de Paragonimus sp. en Fuente Clara. La presencia de formas larvarias y gusanos adultos del digéneo se evaluó en moluscos, crustáceos y mamíferos. En las personas voluntarias se hizo diagnóstico en esputo. Al agua de la quebrada La Puerta se le midieron: coliformes totales/fecales, pH, conductividad y oxígeno disuelto. Con niños y adolescentes se realizaron talleres educativos utilizando técnicas lúdicas. Resultados. Los porcentajes de infección encontrados fueron: caracoles, 0,07 por ciento; cangrejos, 55,5 por ciento; mamíferos, 25 por ciento, y personas, 0 por ciento. Durante los talleres educativos se manifestó la importancia de los recursos naturales del barrio. Los niños identificaron los huéspedes de Paragonimus sp. y detectaron los factores de riesgo para adquirir la enfermedad. Se determinó que el agua de la quebrada La Puerta no es apta para el consumo y la recreación de las personas. Conclusiones. Se señala a Fuente Clara como el primer foco de paragonimosis en zona urbana de Colombia, donde la manipulación y el consumo de cangrejos ponen en riesgo de adquirir la infección a sus habitantes; se sugiere realizar vigilancia de la enfermedad en el sector.

Paragonimiasis: first case reported in Brazil

The authors present a case from a 59 years old white female Brazilian patient, based in Salvador-Bahia, Brazil's northeastern side area, who experienced irritative cough and progressive dyspnea, and, after 18 months, was admitted to a hospital with respiratory insufficiency. The physical exam showed diffuse rales in both hemithoraces. Initial leukogram showed 14,400 cells/mL with 14 percent of eosinophils and chest X-ray showed peribronchovascular infiltrate, predominating in the lower half of the lung fields, and small opaque nodules. The high-resolution computed tomography scan of the chest (HRCT) presented compatible pattern with airways disease, especially from the small airways, with air trapping, tree sprouting images, central lobular nodules and bronchiectasis, making the results compatible with bronchiolitis and bronchiectasis. The transbroncho biopsy unveiled granulomatous lesion with necrosis, where was noticed a structure compatible to a parasitic case, and the research of the parasite eggs in the sputum was positive to paragonimus. After the praziquantel use, the patient presented a thick ferruginous expectoration and the result for BAAR examination was positive. The PCR exam and the sputum culture confirmed M. tuberculosis, and then the treatment for M. tuberculosis was initiated. The authors warn that this infection may have been a consequence of economics globalization process, where the importation of parasitized crustaceans might be the cause. However, there is the need of an accurate examination for the possibility of paragonimus specimens in this area of Brazil.

Paragonimosis in the Cajabamba and Condebamba districts, Cajamarca, Peru

Stool samples from 409 pre-school and school students, living in six villages of the Cajabamba and Condebamba districts, Cajamarca, Perú, were examined using wet preparations and Lumbreras' method, looking for Paragonimus eggs. Fecal and sputum samples from two children (0.5 percent) of 6 and 8 year-old showed eggs of Paragonimus. One hundred and twenty freshwater crabs, Hypolobocera chilensis eigenmanni, were collected from the Condebamba valley and 21 (17.5 percent) of them were infected with P. mexicanus (syn. P. peruvianus) metacercariae. Our results show the persistence of Paragonimus in human beings and in the main source of infection, the crabs

Epidemiology of paragonimiasis in Korea.

In Korea, soybean-sauce soaked freshwater crabs (kejang) have been a favorite delicacy when eating a bowl of rice. This traditional food has been a main source of human paragonimiasis. Until the late 1960s, human paragonimiasis had been prevalent; at least two million people had contracted the infection as determined by intradermal tests. About 40% of these were egg positive. In the turmoil of the green revolution and industrialization in the 1970s/1980s, ecological damage occurred widely. In many streams, populations of snail and crustacean hosts were reduced to levels almost of extinction. Population reduction of the intermediate hosts was followed by lowered endemicity. Attitudes of people, changed during the period, also reduced chances of paragonimiasis. Survey data in the 1990s indicated that prevalence of human paragonimiasis has lowered to about one 100th of that in the early 1970s. In a referral system, however, about one hundred clinical cases have been diagnosed annually by antibody test (ELISA), undertaken for clinical differentiation from tuberculosis. At least 10% of freshwater crabs sold in local markets are infected with the metacercariae. Paragonimiasis control has benefited in Korea mainly by the untoward effects of water pollution. To place P. westermani infections as enzootic, health education and surveillance systems should have a priority.

paragonimiasis in Manipur.

A survey was undertaken in the east district of Imphal valley of Manipur, India, using an intradermal test with saline extract of adult Paragonimus westermani as test antigen to find out the prevalence of paragonimiasis and some of the epidemiological factors attributable to it. A total of 3,467 individuals of both sexes aged five years and above were tested. A total of 2934 persons admitted eating crabs and among them 234 were found reactive to Paragonimus antigen. The prevalence rate observed was 6.7 per cent. The proportion of positive reactors (8.0%) among the crab eaters compared to 0.1 per cent among those who did not eat crabs was highly significant (P < 0.01). The difference in the prevalence rates in different age groups and different sexes was also found to be highly significant. The habit of eating raw and or undercooked crabs had significant correlation with skin reactivity. The intradermal test was found to be a good screening test for mass surveys due to its simplicity, low cost, high sensitivity and no known untoward reaction. Four persons among the skin positive reactors presented with cough, pain in the chest, recurrent haemoptysis as major clinical manifestations. Laboratory investigations revealed Paragonimus eggs in the sputum smears, raised erythrocyte sedimentation rate, and high absolute eosinophil count in their blood. Praziquantel, the drug of choice was given at a dose of 25 mg per kg body weight 3 times a day for three consecutive days to each patient for a cure.

Snail-borne parasitic zoonoses in Korea.

A total of 22 snail-borne parasites causing various parasitic zoonoses in Korea are listed and reviewed. All of these parasites are indigenous except Heterophyes heterophyes, H. dispar and Angiostrongylus cantonensis detected in patients who traveled outside of Korea.

La paragonimiasis pulmonar humana en México / Human lung paragonimiasis in Mexico

Se analiza brevemente la paragonimiasis pulmonar humana en México. Se confirma que esta enfermedad es producida por Paragonimus mexicanus y que hasta ahora es la única especie registrada en nuestro país, cuya distribuición geográfica se extiende desde México hasta Perú. Se señalan las zonas endémicas hasta ahora descubiertas; se precisan tanto a los hospederos definitivos como intermediarios de esta especie y se concluye que, aunque rara y de difícil diagnóstico, puede representar un problema de salud pública

La paragonimiasis en el continente americano / Paragonimiasis in the American Continent

En este trabajo se informa brevemente sobre la paragonimiasis en América, señalándose a la fecha ocho especies del genero Paragonimus, de las cuales P. Kellicotti, P. mexicanus, P. caliensis, y P. amazonicus, son consideradas válidas; P. peruvianus, P. inca y P. ecuadoriensis, se consideran como sinónimos de P. mexicanus y finalmente se señala a P. rudis como "especie inquirenda". Además, se examinan los casos de paragonimiasis en la especie humana registrados en toda América, desde Canadá hasta Brasil, considernado a Ecuador y a Perú como los países con mayor número de casos en América, que dando sólo Guatemala, Panamá y Brasil como los únicos países en donde, hasta ahora, no se ha registrado ningún caso en la especie humana

Primer caso de paragonimiasis erratica humana en el litoral Atlántico de Costa Rica / Report of the first case of human erratic paragonimiasis in the Atlantic Coast of Costa Rica

Se presenta el primer caso de paragonimiasis errática humana en el litoral atlántico de Costa Rica. Se trata de un niño con tumoración inguinoescrotal izquierda, leucocitosis importante con eiosinofilia y radiografía de tórax, con acentuación de la trama vascular pulmonar. Ante la intervención quirúrgica, se encontró una tumoración independiente del testículo. En el estudio patológico, se encontró las huevecillos típicos de Paragonimus mexicanus. El diagnóstico fue corroborado con estudios serológicos e inmunológicos. Este es un caso importante, ya que los casos semejantes reportados en la literatura mundial, son muy escasos, y es la primera vez que se encuentra paragonimiasis humana en la zona atlántica de Costa Rica, estableciéndose así dos franjas geográficas bien definidas en la distribución de esta zoonosis