Disease Control In Brazil Research Articles

Molecular epidemiology of Hepatitis delta virus infection in Minas Gerais state from Brazil, an area outside the hyperendemic region of the Amazon Basin.

BACKGROUND Hepatitis delta virus (HDV) infections in hepatitis B virus (HBV) carriers are the most severe form of viral hepatitis. HDV prevalence is high in the Brazilian Amazon, but studies in other regions of the country are still scarce and often underestimated its prevalence by including a small numbers of individuals.OBJECTIVE This study aimed to determine the serological prevalence of hepatitis D, the genotypes circulating and to evaluate the associated risk factors for acquisition of HDV in Minas Gerais state, Brazil.METHODS We screened plasma samples (n = 498) from HBV chronic carriers for anti-HD antibodies using a commercial enzyme-linked immunosorbent assay (ELISA) kit. For those samples that were positive for anti-HD antibodies, we performed a reverse transcriptase (RT) nested-polymerase chain reaction (nested-PCR) in order to detect the viral genome and identify the viral genotypes circulating in the state.FINDINGS The prevalence was 6.22% (31/498). Blood transfusion was the only risk factor associated with HDV infection [risk ratio: 3.73; 95% confidence interval (CI): 1.44 to 9.65]. For 26 anti-HD positive patients, HDAg gene sequences were determined and in all patients HDV genotype 1 was found.CONCLUSIONS This study confirmed the circulation of HDV in Minas Gerais, an area previously considered non-endemic for hepatitis D in Brazil. The prevalence found in this study is much higher when compared to other studies performed in Brazil, probably because the population in our study was selected with minimal bias. Furthermore, in 26 anti-HD positive plasma samples, we were also able to detect the viral genome, indicating that these patients were experienced an active infection at the time of sample collection. These findings emphasise the importance of anti-HD testing in HBV infected individuals, which may contribute to this disease control in Brazil.

Factors associated with Chagas disease among blood donors in Brazilian Northeast region

Despite the intensification of Chagas disease control in Brazil, around 1980s and 1990s, the transmission still occurs. The aim of this study was to identify the factors associated with Chagas disease among blood donors in Piaui State, Brazilian Northeast Region from 2004 to 2013. Records of 597 blood donors from Management System in Hemotherapy Services and Laboratory Environment Manager System of Piaui were studied. Sociodemographic variables and serological tests results for Chagas disease's confirmation were analyzed using adjusted multiple logistic regression and odds ratio (OR) evaluation. The frequency of serological test confirming Chagas disease was 15.6%. Multivariate analysis showed that the most important associated factors were among blood donors who were born until 1960 (OR 5.1; 95%; CI 1.95-13.14), with low educational level (OR 2.8; 95%; CI 0.75-10.29), who lives in cities with ≤50% of urbanization rate (OR 3.5; 95%; CI 1.42-8.72) and first-time blood donors (OR 3.0; 95%; CI 1.74-5.23). Unfortunately, the factors associated with Chagas disease are still the same pointed out in the scientific literature of decades ago. Our results are in line with the postulate of the 2nd Brazilian Consensus on Chagas disease, regarding the need to develop research that presents new scientific evidence, contributing not only to the Brazilian scenario but also to Latin America.

Visceral leishmaniasis: situation diagnosis from the perspective of disease control in Brazil

Leishmaniasis is a group of neglected diseases that are highly prevalent worldwide, mainly in the developing world, and can take on severe forms. They are transmitted to the man by the bite of phlebotomines, existing a range of animal reservoirs, among which the dog is considered the main urban host. In this context, leishmaniasis, mainly the visceral form, has been urbanized in Brazil, reaching large urban centers throughout the country. In addition, recently, new areas previously unaffected started to present autochthonous cases of human visceral leishmaniasis. The expansion of the disease to new areas has demonstrated the failure of the measures recommended by national health agencies and calls for a new control model in which popular awareness and environmental management are priority actions.

Drug addiction and alcoholism as predictors for tuberculosis treatment default in Brazil: a prospective cohort study.

This study aimed to evaluate the risk factors for tuberculosis (TB) treatment default in a priority city for disease control in Brazil. A cohort of TB cases diagnosed from 2008 to 2009 was followed up from patients' entry into three outpatient sites, in Juiz de Fora, Minas Gerais (Brazil), until the recording of the outcomes. Drug addiction, alcoholism and treatment site appeared to be independently associated with default. Current users of crack as the hardest drug (odds ratio (OR) 12·25, 95% confidence interval (CI) 3·04-49·26) were more likely to default than other hard drug users (OR 5·67, 95% CI 1·34-24·03), former users (OR 4·12, 95% CI 1·11-15·20) and those not known to use drugs (reference group). Consumers at high risk of alcoholism (OR 2·94, 95% CI 1·08-7·99) and those treated in an outpatient hospital unit (OR 8·22, 95% CI 2·79-24·21%) also were more likely to default. Our results establish that substance abuse was independently associated with default. National TB programmes might be more likely to achieve their control targets if they include interventions aimed at improving adherence and cure rates, by diagnosing and treating substance abuse concurrently with standard TB therapy.

Population attributable fraction: planning of diseases prevention actions in Brazil.

ABSTRACTEpidemiology is the study of occurrence, distribution and determinants of health-related events, including the application of that knowledge to the prevention and control of health problems. However, epidemiological studies, in most cases, have limited their research questions to determinants of health outcomes. Research related to the application of knowledge for prevention and control of diseases have been neglected. In this comment, we present a description of how population attributable fraction estimates can provide important elements for planning of prevention and control of diseases in Brazil.

Registro da memória audiovisual do combate à doença de Chagas no município de Cássia dos Coqueiros, São Paulo

Some of the major advances in Chagas’s disease control in Brazil should be credited to Professor José Lima Pedreira de Freitas (1917-1966). From 1947 to 1966, his contributions included development of serological techniques, investigations on the biological aspects of the triatomines, as well as clinical and epidemiological studies. His most relevant achievement, however, was a technique for controlling triatomines based upon selective spraying of insecticide only within infested houses, which was thought and developed in Cassia dos Coqueiros, a small village in the state of São Paulo, Brazil. Named selective purge, this revolutionary technique combined high efficacy, low cost and less environmental risks, which caused it to be largely adopted in the American continent. Unfortunately, its authorship has been missed within the brazilian public health memory, being its association with Cássia dos Coqueiros and Pedreira de Freitas rarely mentioned. The present project aimed at recovering the memory of professor Freitas’s struggle against Chagas’s disease, by developing a documentary involving participation of old local inhabitants and former professors of the Medical School which worked closely to him.

Perspectivas de controle de doenças transmitidas por vetores no Brasil

The analysis of vector borne disease control in Brazil should consider three aspects: the urbanization of the population, change from a rural pattern to concomitant urban or peri-urban transmission and decentralization of control to municipalities. The great majority of the population now lives in urban areas. Some diseases are being transmitted in urban areas, due to the emergence or reemergence of their vectors, such as dengue, malaria and visceral leishmaniasis. Difficulties in control occur, as it is easier to apply control measures in rural areas, because there is more population adherence than in urban areas and so the coverage is higher and disease control is better. The decentralization of control activities to states and municipalities is being implemented and difficulties occur as these levels of government have insufficient accumulated experience in control. For more effective control, political commitment, multi-sector articulation and rational use of insecticide are required.

The finding of Panstrongylus megistus in an artificial ecotope: taking up residence or merely visiting?

As a first measure of Chagas' disease control in Brazil with chemical elimination of the most important vector of the disease, Triatoma infestans was removed. Attention is now being paid to Triatoma sordida and Panstrongylus megistus. That species can eventually be found inside houses, as happened with the specimens we examined from Bernardino de Campos and Sete Barras, all of them infected by Trypanosoma cruzi. These data suggest that a better knowledge about the behavior that species is needed to introduce changes in the control measures.

Tick infestation of livestock and tick control methods in Brazil: A situation report

Boophilus microplus is Brazil's outstanding livestock ectoparasitic pest (annual losses, US$ 1B), affecting, to varying extents, all its States, with a national herd of some 130 M cattle. The country's 8.5 M sq km and 23,000 km of land frontier with 10 tick infested countries complicate any concepts of national campaigns. Whereas Brazil is increasingly climatically suitable for B. microplus from south (three generations annually) to central (four) to north (potentially up to five), direct problems caused are incidentally decreased due to greater use of Bos indicus cattle at lower stocking rates; five tick population survival mechanisms are suggested. Voluntary, empirical chemical tick control remains the tradition, with little government involvement. Formamidine and synthetic pyrethroid acaricides dominate the market, due to former tick resistance to arsenicals, organochlorines and organophosphates, and market forces. Plunge dips, various sprayers, and “pour-on” formulations are used; first suspicions of tick resistance to synthetic pyrethroids have been reported. Various ecologically based “improved” tick control schemes produced promising results experimentally, but require a complementary vaccine against babesiosis/anaplasmosis before wide recommendation. Intensive use of synthetic pyrethroid acaricides has created tick-borne diseases and heightened demand for a live, frozen “vaccine”, in its pre-commercialization phase in Brazil. A strategic research and development approach has been adopted for widespread improvement to cattle ticks and tick-borne disease control in Brazil.