No abstract

SUMMARYHuman T-cell leukemia virus type 1 (HTLV-1), the first human retrovirus to be discovered, is present in diverse regions of the world, where its infection is usually neglected in health care settings and by public health authorities. Since it is usually asymptomatic in the beginning of the infection and disease typically manifests later in life, silent transmission occurs, which is associated with sexual relations, breastfeeding, and blood transfusions. There are no prospects of vaccines, and screening of blood banks and in prenatal care settings is not universal. Therefore, its transmission is active in many areas such as parts of Africa, South and Central America, the Caribbean region, Asia, and Melanesia. It causes serious diseases in humans, including adult T-cell leukemia/lymphoma (ATL) and an incapacitating neurological disease (HTLV-associated myelopathy/tropical spastic paraparesis [HAM/TSP]) besides other afflictions such as uveitis, rheumatic syndromes, and predisposition to helminthic and bacterial infections, among others. These diseases are not curable as yet, and current treatments as well as new perspectives are discussed in the present review.

Cities are the predominant mode of living, and the growth in cities is related to the expansion of areas that have concentrated disadvantage. The foreseeable trend is for rising inequities across a wide range of social and health dimensions. Although qualitatively different, this trend exists in both the developed and developing worlds. Improving the health of people in slums will require new analytic frameworks. The social-determinants approach emphasizes the role of factors that operate at multiple levels, including global, national, municipal, and neighborhood levels, in shaping health. This approach suggests that improving living conditions in such arenas as housing, employment, education, equality, quality of living environment, social support, and health services is central to improving the health of urban populations. While social determinant and multilevel perspectives are not uniquely urban, they are transformed when viewed through the characteristics of cities such as size, density, diversity, and complexity. Ameliorating the immediate living conditions in the cities in which people live offers the greatest promise for reducing morbidity, mortality, and disparities in health and for improving quality of life and well being.

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 80.0% of all blood collected. We conducted a cross-sectional study to assess the geographic distribution of HTLV-I/II serological screening prevalence rates in blood donors from 27 large urban areas in the various States of Brazil, from 1995 to 2000. Enzyme immunoassay (EIA) was used to test for HTLV-I/II. The mean prevalence rates ranged from 0.4/1,000 in Florianópolis, capital of Santa Catarina State, in the South, to 10.0/1,000 in São Luiz, Maranhão State, in the Northeast. EIA prevalence rates are lower in the South and higher in the North and Northeast. The reasons for such heterogeneity may be multiple and need further studies.

No abstract

Interest in self-rated health (SRH) as a tool for use in disease and mortality risk screening is increasing. The authors assessed the discriminatory ability of baseline SRH to predict 10-year mortality rates compared with objectively measured health status. Principal component analysis was used to create a health score that included systolic blood pressure, presence of diabetes mellitus, body mass index, electrocardiographic parameters, B-type natriuretic peptide, and other biochemical and hematologic measures. From 1997 to 2007, a total of 474 of the 1,388 baseline participants died and 81 were lost to follow-up, yielding 11,833 person-years of observation. The adjusted hazard ratio for death was 1.74 (95% confidence interval (CI): 1.32, 2.29) for persons reporting poor health versus those reporting good health. When combined with age and sex, SRH had a C statistic to predict death equal to 0.69 (95% CI: 0.67, 0.71), which was comparable to that of the inclusive health score (C = 0.69, 95% CI: 0.67, 0.72). The addition of other parameters, such as lifestyle, physical functioning, mental symptoms, and physical symptoms, had little effect on these 2 predictive models (C = 0.71 (95% CI: 0.69, 0.73) and C = 0.71 (95% CI: 0.69, 0.74), respectively). The abilities of the SRH and the health score models to predict death decreased in parallel fashion over time. These results suggest that older adults who report poor health warrant particular attention as persons who have accumulated biologic markers of disease.

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. The major modes of transmission have been through sexual contact, blood, and mother to child via breast-feeding. HTLV-1 is associated with adult T-cell leukemia/lymphoma (ATL), HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP), and HTLV-associated uveitis as well as infectious dermatitis of children. More clarification is needed in the possible role of HTLV in rheumatologic, psychiatric, and infectious diseases. Since cures for ATL and HAM/TSP are lacking and no vaccine is available to prevent HTLV-1 and HTLV-2 transmission, these illnesses impose enormous social and financial costs on infected individuals, their families, and health care systems. For this reason, public health interventions aimed at counseling and educating high-risk individuals and populations are of vital importance. In the Americas this is especially important in the areas of high prevalence.

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. HTLV-I causes adult T cell leukemia/lymphoma (ATLL), HTLV associated myelopathy/tropical spastic paraparesis (HAM/TSP), HTLV associated uveitis (HAU), dermatological and immunological abnormalities. HTLV-II is not consistently associated with any disease. Diagnosis is established using screening (enzymatic assays, agglutination) and confirmatory (Western blot, PCR) tests. The viruses are transmitted by blood and contaminated needles, by sexual relations and from mother to child, especially by breast feeding. Prevention efforts should focus on education of positive blood donors, infected mothers and IV drug users.