SHORT REPORT: ENDEMIC FOCUS OF CYSTIC ECHINOCOCCOSIS IN A COASTAL CITY OF PERU PEDRO L. MORO, LUIS LOPERA, MILAGROS CABRERA, GRACE CABRERA, BERNABE SILVA, ROBERT H. GILMAN, AND MANUEL H. MORO Asociacion Benefica PRISMA, Lima, Peru; Public Health Section, School of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru; School of Veterinary Medicine, Universidad San Antonio de Gonzaga de Ica, Ica, Peru; Department of Radiology, Hospital Nacional Arzobispo Loayza, Lima, Peru; Department of International Health, Johns Hopkins School of Hygiene and Public Health, Baltimore, Maryland; Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas Abstract. No evidence of Echinococcus granulosus infection has been described in the coastal region of Peru, with the exception of the capital city of Lima. Anecdotal evidence suggests the existence of a focus of echinococcosis in the coastal city of Chincha, located south of Lima. We conducted a preliminary epidemiologic study in Chincha, which included an ultrasound, chest radiography, and serologic survey of abattoir workers, a review of medical records from local hospitals, and examination of the intestines of stray dogs to determine the presence of canine echinococcosis. Among 25 abattoir workers examined for the presence of cystic echinococcosis, we found three (12%) subjects with echinococcal cysts. A review of medical records showed a surgical incidence of 32/100,000 for the period 1996–1998. Three of 48 dogs (6.25%) were found to be infected with E. granulosus tapeworms. This study demonstrates the existence of an undocumented endemic focus of E. granulosus previously unknown in the coastal region of Peru. Cystic echinococcosis (CE), an infection caused by the lar- val form of Echinococcus granulosus, is a major public health problem in sheep-raising regions of Peru. 1,2 The geography of Peru is highly varied, ranging from coastal desert to high altitude sierra, to Amazonia basin jungle, with gradations of intervening climatic zones. Cystic echinococcosis is known to be highly endemic in the highlands where the prevalence of human, canine, and ovine echinococcosis have been reported to be 9%, 46%, and 65%, respectively. 3 No cases of CE have been described in the jungle region. Autochthonous cases of human and canine echinococcosis have been reported in the capital city of Lima. 4,5 There are a few coastal cities sur- rounded by rural areas where conditions may be adequate for the existence of E. granulosus infection in animals and hu- mans. Anecdotal clinical reports suggest the existence of CE in the coastal city of Chincha located south of Lima. Given the absence of data, we conducted a study in Chincha to establish the presence of autochthonous cases of human and canine echinococcosis. We examined workers from the local city abattoir using imaging and serologic techniques, reviewed medical records from city hospitals for evidence of CE surgi- cal treatment, and examined the intestines of stray dogs for the presence of E. granulosus tapeworms. The coastal city of Chincha (population  52,661) is lo- cated 185 km south of Lima at an elevation of 97 meters above sea level (Figure 1). The population is engaged mainly in agricultural and farming activities. Cattle, sheep, and swine are brought from rural areas surrounding the city or from the Andean region to be slaughtered at the municipal abattoir. Forty-five slaughterhouse workers were asked to volunteer for serologic, ultrasonographic, and chest radiographic exami- nations. The study was reviewed and approved by the ethical review boards of Universidad Peruana Cayetano Heredia, The Johns Hopkins School of Hygiene and Public Health, and Asociacion Benefica PRISMA. Individuals were examined in the supine position using a Shimasonic SDL-32 3.5-MHz por- table ultrasonograph (Shimadzu, Kyoto, Japan) with liquid paraffin as the transducing medium. A brief medical exami- nation was performed prior to examination. Posterior- anterior chest radiographs were taken at Hospital San Jose de Chincha. Human blood samples were obtained by venipunc- ture and taken to the Department of Microbiology at Cayet- ano University. Samples were centrifuged and the sera were aliquoted and stored at -20°C until tested. An enzyme-linked immunoelectrotransfer blot (EITB) for the diagnosis of hu- man CE, which identifies three antigens (8, 16, and 21 kD), was performed as previously described. 6 Workers were shown pictures of hydatid-infected offal and asked if they had ever seen such lesions in the animals slaughtered in the facility. They were questioned about infected viscera disposal, veteri- nary inspection, presence of stray dogs inside or surrounding the abattoir, and a history of CE among them. Medical records from patients who were surgically treated for CE at Hospitals San Jose and Rene Toche were obtained for the period 1996–1998. Forty-eight stray dogs from areas sur- rounding the abattoir were captured and humanely killed. The intestines of freshly killed animals were removed and preserved by inoculating the lumen with 10% formaldehyde and keeping them in the same solution until opened for study. The intestines of dogs were opened and examined for E. granulosus at the School of Veterinary Medicine of the Uni- versidad San Antonio de Gonzaga in Ica. 7 Three of 25 individuals (12%) had either liver or lung cysts detected by ultrsonographic scanning or chest radiographic examination. All were positive on the EITB for CE. One was a 50-year-old man who had a history of surgery for liver CE five years before the study. Ultrasound examination showed a 5.2-cm unilocular cyst in the right lobe of his liver. A second case with liver involvement was a 42-year-old woman with no previous history of CE. A unilocular cyst 4.7 cm in diameter was observed in the right lobe of her liver. The third was a 57-year-old man who had a chest radiograph image compat- ible with a hydatid cyst in his left lung. All were asymptom- atic. The results of physical examinations were normal in all three individuals. None gave a history of residence in an en- demic area in the Andean region of Peru. All workers exam- ined admitted having seen dogs at some point in the past inside the facility, and one admitted to regularly take live- stock offal to feed his dog. All workers had seen hydatid cysts at some point in the past in the abattoir, but none knew how Am. J. Trop. Med. Hyg., 71(3), 2004, pp. 327–329 Copyright © 2004 by The American Society of Tropical Medicine and Hygiene 327