The frequency of the Beijing genotype ofMycobacterium tuberculosis as a cause of tuberculosis (TB) in South America was determined by analyzing genotypes of strains isolated from patients that had been diagnosed with the disease between 1997 and 2003 in seven countries of the subcontinent. In total, 19 of the 1,202 (1.6%) TB cases carried Beijing isolates, including 11 of the 185 patients from Peru (5.9%), five of the 512 patients from Argentina (1.0%), two of the 252 Brazilian cases (0.8%), one of the 166 patients from Paraguay (0.6%) and none of the samples obtained from Chile (35), Colombia (36) and Ecuador (16). Except for two patients that were East Asian immigrants, all cases with Beijing strains were native South Americans. No association was found between carrying a strain with the Beijing genotype and having drug or multi-drug resistant disease. Our data show that presently transmission of M. tuberculosis strains of the Beijing genotype is not frequent in Latin America. In addition, the lack of association of drug resistant TB and infection withM. tuberculosis of the Beijing genotype observed presently demands efforts to define better the contribution of the virulence and lack of response to treatment to the growing spread of Beijing strains observed in other parts of the world.

Fil: Ritacco, Viviana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.

Fil: López, Beatriz. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.

Fil: Cafrune, Patricia I. Universidade Federal do Rio Grande do Sul; Brasil.

Fil: Ferrazoli, Lucilaine. Instituto Adolfo Lutz; Brasil.

Fil: Suffys, Philip N. Instituto Oswaldo Cruz-Fiocruz; Brasil.

Fil: Candia, Norma. Instituto de Investigaciones en Ciencias de la Salud; Paraguay.

Fil: Vasquez, Lucy. Instituto Nacional de Salud; Peru.

Fil: Realpe, Teresa. Corporación para Investigaciones Biológicas; Colombia.

Fil: Fernández, Jorge. Instituto de Salud Pública de Chile; Chile.

Fil: Lima, Karla V. Instituto Evandro Chagas; Brasil.

Fil: Zurita, Jeannete. Hospital Vozandes; Ecuador.

Fil: Robledo, Jaime. Corporación para Investigaciones Biológicas; Colombia.

Fil: Rossetti, Maria L. Universidade Federal do Rio Grande do Sul; Brasil.

Fil: Kritski, Afrânio L. Universidade Federal do Rio de Janeiro; Brasil.

Fil: Telles, María A. Instituto Adolfo Lutz; Brasil.

Fil: Palomino, Juan C. Institute of Tropical Medicine; Belgica.

Fil: Heersma, Herre. National Institute of Public Health and the Environment; Paises Bajos.

Fil: van Soolingen, Dick. National Institute of Public Health and the Environment; Paises Bajos.

Fil: Kremer, Kristin. National Institute of Public Health and the Environment; Paises Bajos.

Fil: Barrera, Lucía. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.