title: Laboratory surveillance of dengue in Rio Grande do Sul, Brazil, from 2007 to 2013.
abstract: BACKGROUND
  According to official records, dengue was introduced in Brazil in the 80's; since then several epidemics have occurred. Meanwhile, in Rio Grande do Sul (RS, Southern Brazil) the first autochthonous case occurred only in 2007.
  
  
  RESULTS
  In this study we report laboratory surveillance of dengue cases and seasonality of positive cases, describe serotypes and characterize the epidemiological pattern of dengue in RS from 2007 to 2013. A total of 9,779 serum samples from patients with suspected dengue fever were collected and submitted to molecular and/or serological analyses for dengue virus identification and serotyping, based on viral isolation, NS1 antigen detection and qRT-PCR, or Dengue IgM capture ELISA and MAC-ELISA. The first autochthonous dengue case in RS was confirmed in 2007 (DENV-3). While in 2008 and 2009 only imported cases were registered, autochthonous infection waves have been occurring since 2010. The highest number of dengue infections occurred in 2010, with DENV-1 and DENV-2 outbreaks in Northwestern RS. In 2011, another DENV-1 and DENV-2 outbreak occurred in the Northwestern region; moreover, DENV-4 was detected in travelers. In 2012, DENV-1 and DENV-4 co-circulated. DENV-2 circulation was only detected again in 2013, in high frequency (56.7%), co-circulating with DENV-4 (35%). Most infections occur in adults during summer. Differences in prevalence between genders were observed in 2007 (60% females), 2008 (60.8% males) and 2009 (77.5% males).
  
  
  CONCLUSIONS
  According to results of dengue surveillance, there was an increase in the number of dengue cases in RS and of cities infested with Aedes aegypti, possibly as a consequence of introduction of new serotypes and the difficulty of health programs to control the vector.
authors.affiliation: Laboratory of Molecular Biology, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, RS, Brazil; Graduate Program in Pathology, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, RS, Brazil; Fundação Estadual de Produção e Pesquisa em Saúde - Instituto de Pesquisas Biológicas - Laboratório Central de Saúde Pública do Rio Grande do Sul (FEPPS IPB-LACEN/RS), Porto Alegre, RS, Brazil.
authors.forename: Gabriela Luchiari
authors.initials: GL
authors.lastname: Tumioto
authors.affiliation: Fundação Estadual de Produção e Pesquisa em Saúde - Instituto de Pesquisas Biológicas - Laboratório Central de Saúde Pública do Rio Grande do Sul (FEPPS IPB-LACEN/RS), Porto Alegre, RS, Brazil.
authors.forename: Tatiana Schäffer
authors.initials: TS
authors.lastname: Gregianini
authors.affiliation: Fundação Estadual de Produção e Pesquisa em Saúde - Instituto de Pesquisas Biológicas - Laboratório Central de Saúde Pública do Rio Grande do Sul (FEPPS IPB-LACEN/RS), Porto Alegre, RS, Brazil.
authors.forename: Bibiana Paula
authors.initials: BP
authors.lastname: Dambros
authors.affiliation: Fundação Estadual de Produção e Pesquisa em Saúde - Instituto de Pesquisas Biológicas - Laboratório Central de Saúde Pública do Rio Grande do Sul (FEPPS IPB-LACEN/RS), Porto Alegre, RS, Brazil.
authors.forename: Beatriz Carneiro
authors.initials: BC
authors.lastname: Cestari
authors.affiliation: Fundação Estadual de Produção e Pesquisa em Saúde - Instituto de Pesquisas Biológicas - Laboratório Central de Saúde Pública do Rio Grande do Sul (FEPPS IPB-LACEN/RS), Porto Alegre, RS, Brazil.
authors.forename: Zenaida Marion
authors.initials: ZM
authors.lastname: Alves Nunes
authors.affiliation: Laboratory of Molecular Biology, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, RS, Brazil; Graduate Program in Pathology, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, RS, Brazil.
authors.forename: Ana Beatriz Gorini
authors.initials: AB
authors.lastname: Veiga
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D003715:Dengue / Q000453:epidemiology* / Q000266:history / Q000821:virology*; D003716:Dengue Virus / Q000145:classification / Q000235:genetics; D004196:Disease Outbreaks; D005260:Female; D049674:History, 21st Century; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D012621:Seasons; D012703:Serotyping; D055815:Young Adult