Human fascioliasis in Argentina: a multidisciplinary analysis

MERA Y SIERRA R.L.; AGRAMUNT VH.; CUERVO, PABLO F.; MAS-COMA, SANTIAGO

Cluj-Napoca

Congreso; XI European Multicolloquium of Parasitology; 2012

Human fascioliasis is currently emerging worlwide and endemic regions are recognized in Latin America, Europe, Africa and Asia. The highest known prevalence and intensities of human fascioliasis occur in Latin America in Andean regions of Bolivia and Peru. In Argentina, fascioliasis has always been considered an important disease affecting animals and national slaughterhouse reports are available, yet human fascioliasis is not of obligatory declaration and has never been adequately addressed despite the proximity and the geographical and climatic similarities with the endemic areas. The only information of human cases is that available in published and unpublished written reports; a previous review accounted for 85 human cases. The purpose of this research is to provide an in-depth analysis of the results obtained in a thorough bibliographical search of human fascioliasis in Argentina. In total, 58 reports were identified which described 619 cases. The majority (97.7%) from mountainous regions concentrated in central and western Argentina with very few cases in the rest of the country, not matching the distribution of animal fascioliasis. The age of the patients ranged from 3 to 95 years (mean 37.1) and 55% of the patients were female. Wild watercress ingestion was the main risk factor, described in 214 patients, during recreational, weekend or holiday activities. Eleven family outbreaks involving 63 persons are described. Diagnosis mainly relied on egg finding (288), followed by serology (82), intradermal reaction (63), surgery (45), and erratic fluke observation (6). A delay in diagnosis (average 3.5 years) and high lithiasis proportion and surgery reports suggest that many patients are frequently overlooked. In cases when the month of the appearance of the first symptoms was noted ,most of the cases occur during summer and early fall correlating significantly with monthly precipitation, monthly maximum temperature and monthly minimum temperature a with a time lag of 3 months which fits with the logical delay between infection moment and symptom appearance and diagnosis. This also coincides with field activities during summer holidays and would explain the second peak observed in June related to the Easter Holidays. Emetine appears as the drug most used (186), replaced by triclabendazole in recent years (21). Surgery reports are numerous (27.0%).High seroprevalences found in recent random surveys suggest human endemic situations. This analysis highlights that human fascioliasis may have been overlooked in the past and may be currently underestimated.