RESUMO
SETTING: Five medical schools in three cities with different tuberculosis (TB) incidence rates in Rio de Janeiro State, Brazil. OBJECTIVE: To estimate prevalence of and associated factors for latent tuberculosis infection (LTBI) among medical students. DESIGN: A cross-sectional survey was conducted among undergraduate students in pre-clinical, early and late clinical years from schools in cities with low (28/100,000), intermediate (63/100,000) and high (114/100,000) TB incidence rates. Information on socio-demographic profile, previous BCG vaccination, potential TB exposure, co-morbidity and use of respiratory protective masks was obtained. A tuberculin skin test (TST) was performed using the Mantoux technique by an experienced professional. A positive TST, defined as induration > or = 10 mm, was considered LTBI. RESULTS: LTBI prevalence was 6.9% (95%CI 5.4-8.6). In multivariate analysis, male sex (adjusted odds ratio [aOR] 1.8; 95% CI 1.1-3.0), late clinical years (aOR 1.9; 95% CI 1.01-3.5), intermediate TB incidence (aOR 4.3; 95% CI 1.3-14.6) and high TB incidence in the city of medical school (aOR 5.1; 95% CI 1.6-16.8) were significantly associated with LTBI. CONCLUSIONS: The higher prevalence of LTBI in late clinical years suggests that medical students are at increased risk for nosocomial Mycobacterium tuberculosis infection. The implementation of a TB control program may be necessary in medical schools, particularly in cities with higher TB incidence.
Assuntos
Infecção Hospitalar , Estudantes de Medicina , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/transmissão , Adulto , Brasil , Estudos Transversais , Educação de Graduação em Medicina , Feminino , Inquéritos Epidemiológicos , Humanos , Incidência , Controle de Infecções , Masculino , Prevalência , Fatores de RiscoRESUMO
Cohort studies have been of great importance in the establishment of what is known about the epidemiology of tuberculosis. The individuals who conducted these studies provided useful models for the application of life table, person-time, and cohort analyses to the study of diseases. These tuberculosis workers not only have shown that follow-up of large cohorts can be virtually complete, but, even more importantly for future cohort studies, they have also shown how cohort investigations can be done at minimal expense.
Assuntos
Análise Atuarial/história , Tuberculose Pulmonar/história , Métodos Epidemiológicos , Seguimentos , História do Século XIX , História do Século XX , Humanos , Porto Rico , Estados UnidosRESUMO
From 1949 to 1951, a controlled trial of BCG vaccinations was conducted in Puerto Rico. The 191,827 children, 1-18 years of age, initially enrolled in the study were skin-tested with tuberculin to determine their eligibility for vaccination. A total of 82,269 children were classified as reactors and not vaccinated. Of the 109, 558 nonreactors, 31,586 refused vaccination, 50,634 were vaccinated with BCG, and 27,338 were left unvaccinated as controls. We ascertained the incidence of cancer over an average follow-up period of 23.3 years in the latter two groups using the Puerto Rico Central Cancer Registry. By the end of December 1973, a total of 77 cancers had been diagnosed among the controls and 150 among the vaccinees. The overall incidence of cancer among the two groups was similar. Although a number of differences existed between the vaccinee group and the controls in regard to the incidence of cancer at various "sites", none of these differences was statistically significant. However, when cases of lymphosarcoma and Hodgkin's disease were combined for analysis, a statistically significant excess of cases occurred among the vaccinees. We concluded that BCG vaccination had no protective effect on the subsequent development of cancer in this population. The slight excess of cases of lymphosarcoma and Hodgkin's disease among the vaccinees raised the possibility that BCG may have had an adverse effect.
Assuntos
Vacina BCG/farmacologia , Neoplasias/prevenção & controle , Adolescente , Vacina BCG/efeitos adversos , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Feminino , Seguimentos , Doença de Hodgkin/epidemiologia , Doença de Hodgkin/etiologia , Humanos , Lactente , Leucemia/epidemiologia , Linfoma não Hodgkin/epidemiologia , Linfoma não Hodgkin/etiologia , Masculino , Neoplasias/epidemiologia , Porto RicoAssuntos
Tuberculose/epidemiologia , Adolescente , Adulto , Idoso , Vacina BCG , População Negra , Criança , Pré-Escolar , Inglaterra , Características da Família , História do Século XX , Humanos , Índia , Sarampo/transmissão , Pessoa de Meia-Idade , Medicina Militar , Caxumba/transmissão , Medicina Naval , Saúde Pública/história , Porto Rico , Fatores Sexuais , Tuberculina , Teste Tuberculínico , Tuberculose/história , Tuberculose/transmissão , Estados Unidos , População Branca , Coqueluche/transmissãoRESUMO
From 1949 to 1951, a total of 191,827 children in Puerto Rico were enrolled in a controlled trial of BCG vaccination. Of these children, 1 through 18 years of age, 82,269 were classified as reactors to tuberculin and 109,558 as nonreactors. Of the nonreactors, 31,856 refused vaccination, 27,338 were left unvaccinated as controls, and 50,674 were vaccinated with BCG. By the end of June 1969, a total of 37 cases of cancer had been diagnosed among the controls and 98 among the "vaccinees," yielding average annual rates of 7.2 and 10.3 cases per 100,000 population, respectively. The vaccinated group had a slight deficiency of leukemia cases and an excess of lymphosarcoma and Hodgkin's disease. The excess risk of cancer was concentrated among children age 10 through 18 on entry into the trial.