Immunologic markers, uveitis, and keratoconjunctivitis sicca associated with human T-cell lymphotropic virus type 1.

Purpose: To verify the occurrence of keratoconjunctivitis sicca (KCS) and human T-cell lymphotropic virus type 1 (HTLV-1) associated uveitis (HAU) and to evaluate the immunologic status related to HTLV-1.

Design: Cross-sectional study.

Methods: Ophthalmic examination (both eyes) and immunophenotyping of peripheral blood lymphocytes were performed in 207 infected asymptomatic blood donors (AS), 55 controls (NI), and 55 patients with HTLV-1 associated myelopathy (HAM/TSP).

HTLV in the Americas: challenges and perspectives.

The first description of the human T-lymphotropic virus type 1 (HTLV-1) was made in 1980, followed closely by the discovery of HTLV-2, in 1982. Since then, the main characteristics of these viruses, commonly referred to as HTLV-1/2, have been thoroughly studied. Central and South America and the Caribbean are areas of high prevalence of HTLV-1 and HTVL-2 and have clusters of infected people.

Global epidemiology of HTLV-I infection and associated diseases.

Epidemiologic aspects of human T-lymphotropic virus type I (HTLV-I) infection have been thoroughly studied over the course of approximately 25 years since its first description. The geographic distribution of the virus has been defined, with Japan, Africa, Caribbean islands and South America emerging as the areas of highest prevalence. The reasons for HTLV-I clustering, such as the high ubiquity in southwestern Japan but low prevalence in neighboring regions of Korea, China and eastern Russia are still unknown.

HTLV-2 horizontal and vertical transmission in a family from a Brazilian urban area: seroepidemiological, clinical and molecular study.

Human T cell lymphotropic virus type 2 (HTLV-2) has been shown to be endemic in Brazilian Indians and among intravenous drug users in urban areas, but transmission of this infection seems to be infrequent in the general population living in urban areas in Brazil. Six persons in three generations of a Brazilian family were evaluated to assess HTLV-2 transmission and its molecular features in the positive cases. The index was detected during screening (HTLV EIA) of donated blood in Fundação Hemominas, Belo Horizonte, Brazil.

Heterogeneous geographic distribution of human T-cell lymphotropic viruses I and II (HTLV-I/II): serological screening prevalence rates in blood donors from large urban areas in Brazil.

Brazil may have the highest absolute number of HTLV-I/II seropositive individuals in the world. Screening potential blood donors for HTLV-I/II is mandatory in Brazil. The public blood center network accounts for about 80.

[Human T-cell lymphotropic virus in family members of seropositive blood donors: silent dissemination].

Objective: To investigate human T-cell lymphotropic virus transmission among family members of asymptomatic carriers identified through blood donor screening tests; and to determine the most likely direction of transmission in sexual partners having the same (concordant) serological diagnosis.

Methods: Between March 1997 and June 2003 the relatives and steady sexual partners of seropositive, asymptomatic blood donors were investigated for the presence of human T-cell lymphotropic virus type I and II. Diagnosis was based on enzyme-linked immunoassay and Western blot.

HTLV-I/II and blood donors: determinants associated with seropositivity in a low risk population.

Objective: Blood donors in Brazil have been routinely screened for HTLV-I/II since 1993. A study was performed to estimate the prevalence of HTLV-I/II infection in a low risk population and to better understand determinants associated with seropositivity.

Methods: HTLV-I/II seropositive (n=135), indeterminate (n=167) and seronegative blood donors (n=116) were enrolled in an open prevalence prospective cohort study.

[Infection and disease caused by the human T cell lymphotropic viruses type I and II in Brazil].

HTLV-I/II infection is present in all regions of Brazil, but its prevalence varies according to the geographical area, being higher in Bahia, Pernambuco and Pará. It has been estimated that Brazil has the highest absolute number of infected individuals in the world. Blood donors screening and research conducted with special groups (indigenous population of Brazil, IV drug users and pregnant women) are the major sources of information about these viruses in our Country.

Human T cell lymphotropic viruses (HTLV-I/II) in South America: should it be a public health concern?

The presence of the human T cell lymphotropic virus (HTLV-I/II) in South America is well established. Its origin and spectrum in the continent still remain a matter of debate. There are signs now that HTLV-I/II was already present in the Amerindian population coming originally from Asia and that HTLV-I was also introduced with African slave trade and with immigration of individuals from endemic areas of Japan.