Ricardo Veronesi

HTLV-Is in Argentina are phylogenetically similar to those of other South American countries, but different from HTLV-Is in Africa

To understand the origin and past dissemination of human T‐cell leukemia/lymphotropic virus type I (HTLV‐I) in Latin America, we conducted a phylogenetic study of five new HTLV‐I isolates from Argentina. We sequenced partial fragments of long terminal repeats (LTR) of the new HTLV‐Is, and then the sequences were subjected to a phylogenetic analysis for comparison with other HTLV‐Is of various geographical origins. Our results indicated that all the isolates were members of the Cosmopolitan group. Furthermore, most (four out of five isolates) of the new HTLV‐Is belonged to the Transcontinental (A) subgroup, the most widespread subgroup of the four subgroups in the Cosmopolitan group. In this subgroup, they were closely related to HTLV‐Is found in other South American countries including those of Amerindians, and were different from those found in Africa. In contrast, the remaining one HTLV‐I (ARGMF) did not show any clear similarity to known HTLV‐I isolates belonging to the Cosmopolitan group. The close similarity of South American HTLV‐Is strongly suggests a common origin of the virus in this continent. Our results do not support the proposed idea of recent introduction of HTLV‐I into South America as a consequence of the slave trade from Africa, where phylogenetically different HTLV‐Is predominate. J. Med. Virol. 55:152–160, 1998.

Viabilidade da aplicação do teste tuberculínico com o dermo-jet

Foram estudadas as reacoes de hipersensibilidade tuberculinica induzidas por aplicacoes simultâneas, em adultos jovens, de tuberculina (PPD. RT-23, 2UT), com agulha e seringa e com o dermo-jet. Foram encontrados 61,3% de reatores nas aplicacoes com agulha e seringa para 40,0% de reatores nas aplicacoes com o dermo-jet. Os resultados nao sao considerados favoraveis ao uso do injetor a jato na pratica corrente de aplicacao do teste tuberculinico.