Epidemiological trends of dengue disease in Brazil (2000-2010): a systematic literature search and analysis

Abstract

A literature survey and analysis was conducted to describe the epidemiology of dengue disease in Brazil reported between 2000 and 2010. The protocol was registered on PROSPERO (CRD42011001826: http://www.crd.york.ac.uk/prospero/display_record.asp?ID=CRD42011001826). Between 31 July and 4 August 2011, the published literature was searched for epidemiological studies of dengue disease, using specific search strategies for each electronic database. A total of 714 relevant citations were identified, 51 of which fulfilled the inclusion criteria. The epidemiology of dengue disease in Brazil, in this period, was characterized by increases in the geographical spread and incidence of reported cases. The overall increase in dengue disease was accompanied by a rise in the proportion of severe cases. The epidemiological pattern of dengue disease in Brazil is complex and the changes observed during this review period are likely to have been influenced by multiple factors. Several gaps in epidemiological knowledge regarding dengue disease in Brazil were identified that provide avenues for future research, in particular, studies of regional differences, genotype evolution, and age-stratified seroprevalence.

Systematic review registration: PROSPERO registration number: CRD42011001826.

Figure 1. Result of literature search and evaluation of identified studies according to the preferred reporting items of systematic reviews and meta-analyses (PRISMA).

All references identified in the on-line database searches were assigned a unique identification number. Following the removal of duplicates and articles that did not satisfy the inclusion criteria from review of the titles and abstracts, the full papers of the first selection of references were retrieved either electronically or in paper form. A further selection was made based on review of the full text of the articles.

Figure 2. Trends in epidemiology of dengue disease Brazil, 2000–2010.

(A) Reported number and average incidence per 100,000 population of probable* cases of dengue disease. (B) Reported number of cases of dengue fever with complications (DFC) and dengue haemorrhagic fever (DHF). (C) Reported number of dengue disease related hospitalizations (DFC+DHF) and deaths due to DFC and DHF. (D) Number of Ae. aegypti-infested municipalities. (E). Average incidence of dengue disease per 100,000 population, by region. The epidemiology of dengue disease in Brazil during the review period suggests that incidence and disease severity increased over the decade, although the situation is complicated by national epidemics in 2002, 2008 and 2010. The incidence of dengue disease over the review period reflects the wide distribution of Ae. aegypti nationally. In most regions the dengue disease incidence followed national trends. (Adapted from Teixeira 2009 and Siqueira 2010 ; additional data supplied by Teixeira MG and Siqueira JB, 2012).

Figure 3. Distribution of reported hospitalized dengue disease cases according to age, Brazil, 2002–2010.

A reduction in the first quartile of dengue disease hospitalizations is evident in 2007–2008, although data from 2009 suggest this change may have been transient. Data are median, first and third quartiles, and minimum and maximum ages; the dashed line indicates age 15 years. (Siqueira 2010 . Figure updated and reproduced with kind permission from the Secretariat of Health Surveillance (SVS) of the Ministry of Health of Brazil; additional data supplied by Siqueira JB, 2012).

Figure 4. Change in pattern of circulating dengue virus (DENV) serotypes by year, (A) Brazil, 2000–2008 and (B) the Northeast region state of Ceará, 2001–2008.

The Brazilian Ministry of Health data from 2000–2008, indicated co-circulation of multiple DENV serotypes with a high proportion of DENV-1 incidence at the beginning of the decade; DENV-3 became predominant from 2003 and DENV-2 was important from 2007. DENV-4 was not present in Brazil until 2011. A similar pattern was observed in the Northeast region state of Ceará. (A: data supplied by Teixeira MG, 2012; B: Cavalcanti 2011 [39]).