RESUMO
A seroepidemiologic survey conducted in 1971 in the rural Pacific coastal community of Chila in the Mexican state of Oaxaca showed an unusually high prevalence of antibody against the Chagas' disease agent Trypanosoma cruzi. Further studies were undertaken in 1973 and 1981 to (1) determine the pathologic impact of T. cruzi infection in humans, (2) investigate the natural history of the disease, (3) confirm that serologically positive persons were parasitologically positive, and (4) evaluate whether T. cruzi transmission continued into the next decade. This article reports results derived from those studies.
PIP: In 1971, health workers drew blood samples from 238 people living in the rural Pacific coastal village of Chile in Oaxaca State, Mexico to determine seroprevalence of antibodies against Trypanosoma cruzi--the parasite responsible for Chagas' disease. Seroprevalence was 5% in 16 year old children, but increased from 41% to 62% to a peak of 78% for 16-19, 20-29, and 30-39 year olds respectively then fell to 68% for 40-49 year olds only to climb again to 75% in 50-59 year olds and fell again to 47% for =or 60 year olds. Overall seroprevalence for adults was 67%. By 1981, adult seroprevalence had fallen to 33% and childhood prevalence to 0.7%. The very low levels of T. cruzi antibodies in children corresponded with insecticide (DDT) spraying for malaria control and with the disappearance of triatomine bugs from Chile. Medical histories revealed that seropositive individuals were more likely to exhibit acute signs and symptoms of initial bite lesions (Romana's sign), furuncle like skin lesions (Chagoma), and facial or body edema (p.05). They also tended to suffer from chronic fatigue and difficult breathing while lying down (p.05). 1973 electrocardiogram (ECG) results showed that seropositive individuals were significantly more likely to have complete right bundle branch block (p.005) and premature ventricular contractions (p.05) than seronegative individuals. There were no seroconversions among 57 people examined with ECGs between 1971-1983. Even though more seropositives (21%) experienced a progression of ECG abnormalities (3% rate/year) than seronegatives (7%), the difference was not significant. Despite reductions in seroprevalence and in triatomine bug population, serologic surveillance and monitoring to detect repopulation of houses by the bugs should be maintained.
Assuntos
Doença de Chagas/epidemiologia , Adolescente , Adulto , Animais , Anticorpos Antiprotozoários/sangue , Bloqueio de Ramo/epidemiologia , Bloqueio de Ramo/etiologia , Doença de Chagas/complicações , Doença de Chagas/imunologia , Criança , Pré-Escolar , Estudos Transversais , Eletrocardiografia , Feminino , Seguimentos , Humanos , Lactente , Estudos Longitudinais , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Prevalência , Saúde da População Rural , Trypanosoma cruzi/imunologiaRESUMO
Postrevolutionary Nicaragua has developed a new health system in which primary health care is a central component. Great progress has been made in correcting the poor health conditions that existed prior to the revolution. As part of an interdisciplinary health team that emphasizes prevention and community service, physicians in the new system play a different role than they did previously. Training for health workers of all types has been expanded. However, scarce teaching and curricular resources have restrained progress in this area. The U.S. based Committee for Health Rights in Central America (CHRICA) has collaborated with the Nicaraguan Ministry of Health to organize two Colloquia on Health in Nicaragua in the past two years. These Colloquia brought together North American participants who provided current medical training and Nicaraguan participants who provided information about the new health system. The Colloquia, whose participants were eligible to receive CME credit from the UCSF School of Medicine, have led to continuing educational exchanges between health care personnel in the two countries.