Epidemiological and immunological aspects of human visceral leishmaniasis on Margarita Island, Venezuela

• Main Authors: Olga Zerpa, Marian Ulrich, Margarita Benitez, Concepción Ávila, Vestalia Rodríguez, Marta Centeno, Doris Belizario, Steven G Reed, Jacinto Convit
• Format: Article
• Language: English
• Published: Instituto Oswaldo Cruz, Ministério da Saúde 2002-12-01
• Series: Memórias do Instituto Oswaldo Cruz.
• Subjects: American visceral leishmaniasis; rK39 antigen; leishmanin reactions; control; Margarita Island; Venezuela
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0074-02762002000800002

Sixty-five patients were diagnosed with visceral leishmaniasis (VL) on Margarita Island in the decade from 1990 to1999; 86.2% were <= 3 years old. All were leishmanin-negative at diagnosis. Evaluation of 23 cured patients in 1999 revealed that 22/23 had converted to leishmanin-positive; five had persisting antibodies to rK39 antigen, with no clinical evidence of disease. Leishmanin tests were positive in 20.2% of 1,643 healthy individuals from 417 households in endemic areas. Of the positive reactors, 39.8% were identified in 35 (8.4%) of the households, 15 of which had an antecedent case of VL, a serologically positive dog or both. Weak serological activity to rK39 antigen was detected in 3 of 488 human sera from the endemic areas. The presence of micro-foci of intense peri-urban transmission and the apparent absence of other Trypanosomatidae causing human disease offer a unique opportunity for the study of reservoirs, alternative vectors and evaluation of control measures on the Island.