[Epidemiological study of Brazilian purpuric fever. Epidemic in a locality of São Paulo state (Brazil), 1986]

Path of infectious diseases in Brazil in the last 50 years: an ongoing challenge

In this article, we comment on the main features of infectious diseases in Brazil in the last 50 years, highlighting how much of this path Revista de Saúde Pública could portray. From 1967 to 2016, 1,335 articles focusing on infectious diseases were published in Revista de Saúde Pública. Although the proportion of articles on the topic have decreased from about 50.0% to 15.0%, its notability remained and reflected the growing complexity of the research required for its control. It is noteworthy that studies design and analysis strategies progressively became more sophisticated, following the great development of epidemiology in Brazil in the recent decades. Thus, the journal has followed the success of public health interventions that permitted to control or eliminate numerous infectious diseases - which were responsible, in the past, for high rates of morbidity and mortality -, and also followed the reemergence of diseases already controlled and the emergence of until then unknown diseases, with a strong impact on the Brazilian population, establishing a little predictable and very challenging path. RESUMO Neste artigo, comentamos as principais características das doenças infecciosas no Brasil, nos últimos 50 anos, destacando o quanto a Revista de Saúde Pública conseguiu capturar essa trajetória. De 1967 a 2016, foram publicados 1.335 artigos na Revista de Saúde Pública com foco em doenças infecciosas. Ainda que a proporção de artigos sobre esse tema tenha declinado de cerca de 50,0% para 15,0%, seu destaque se manteve e refletiu a crescente complexidade das pesquisas necessárias para o seu controle. Nota-se que os desenhos dos estudos e as estratégias de análise ganharam progressivamente maior sofisticação, acompanhando o grande desenvolvimento da epidemiologia no Brasil, nas últimas décadas. Assim, foi registrado não apenas o sucesso de intervenções de saúde pública que permitiram o controle ou a eliminação de inúmeras doenças infecciosas responsáveis, no passado, por elevadas taxas de morbimortalidade, como também a reemergência de males já controlados e o surgimento de doenças até então desconhecidas, com forte impacto na população brasileira, desenhando uma trajetória pouco previsível e muito desafiadora.

Successes and failures in the control of infectious diseases in Brazil: social and environmental context, policies, interventions, and research needs

Despite pronounced reductions in the number of deaths due to infectious diseases over the past six decades, infectious diseases are still a public health problem in Brazil. In this report, we discuss the major successes and failures in the control of infectious diseases in Brazil, and identify research needs and policies to further improve control or interrupt transmission. Control of diseases such as cholera, Chagas disease, and those preventable by vaccination has been successful through efficient public policies and concerted efforts from different levels of government and civil society. For these diseases, policies dealt with key determinants (eg, the quality of water and basic sanitation, vector control), provided access to preventive resources (such as vaccines), and successfully integrated health policies with broader social policies. Diseases for which control has failed (such as dengue fever and visceral leishmaniasis) are vector-borne diseases with changing epidemiological profiles and major difficulties in treatment (in the case of dengue fever, no treatment is available). Diseases for which control has been partly successful have complex transmission patterns related to adverse environmental, social, economic, or unknown determinants; are sometimes transmitted by insect vectors that are difficult to control; and are mostly chronic diseases with long infectious periods that require lengthy periods of treatment.

Emergence and disappearance of a virulent clone of Haemophilus influenzae biogroup aegyptius, cause of Brazilian purpuric fever

SUMMARY

In 1984, children presented to the emergency department of a hospital in the small town of Promissão, São Paulo State, Brazil, with an acute febrile illness that rapidly progressed to death. Local clinicians and public health officials recognized that these children had an unusual illness, which led to outbreak investigations conducted by Brazilian health officials in collaboration with the U.S. Centers for Disease Control and Prevention. The studies that followed are an excellent example of the coordinated and parallel studies that are used to investigate outbreaks of a new disease, which became known as Brazilian purpuric fever (BPF). In the first outbreak investigation, a case-control study confirmed an association between BPF and antecedent conjunctivitis but the etiology of the disease could not be determined. In a subsequent outbreak, children with BPF were found to have bacteremia caused by Haemophilus influenzae biogroup aegyptius (H. aegyptius), an organism previously known mainly to cause self-limited purulent conjunctivitis. Molecular characterization of blood and other isolates demonstrated the clonal nature of the H. aegyptius strains that caused BPF, which were genetically distant from the diverse strains that cause only conjunctivitis. This led to an intense effort to identify the factors causing the unusual invasiveness of the BPF clone, which has yet to definitively identify the virulence factor or factors involved. After a series of outbreaks and sporadic cases through 1993, no additional cases of BPF have been reported.

Cem anos de endemias e epidemias

Este ensaio traça, resumidamente, um panorama das principais epidemias e endemias que acometeram a população do estado de São Paulo, no século XX. Os fatos são apresentados agrupados em cinco períodos, definidos a partir de fatos marcantes da vida nacional. Situa a ocorrência dos problemas de saúde no contexto econômico social e político de cada período. As informações baseiam-se em revisão, não exaustiva, de alguns periódicos científicos da área de saúde pública e medicina. Os períodos considerados são: do início do século ao final da República Velha, o período getulista, a redemocratização de 1945 a 1964, a ditadura militar e o período atual após a queda da ditadura. Para cada período descreve-se a situação epidemiológica das principais endemias e epidemias e para as quais havia dados ou informações disponíveis. Dada a extensão limitada de um artigo, não foi possível aprofundar os aspectos relacionados ao surgimento de cada um dos problemas, nem os detalhes de seu controle. Optou-se pela construção de um painel que possibilitasse aos leitores uma visão de conjunto do século XX. A lista de referências bibliográficas poderá ser útil àqueles que desejarem se aprofundar nos diferentes temas tratados.