title: Arboviral etiologies of acute febrile illnesses in Western South America, 2000-2007.
abstract: BACKGROUND
  Arthropod-borne viruses (arboviruses) are among the most common agents of human febrile illness worldwide and the most important emerging pathogens, causing multiple notable epidemics of human disease over recent decades. Despite the public health relevance, little is know about the geographic distribution, relative impact, and risk factors for arbovirus infection in many regions of the world. Our objectives were to describe the arboviruses associated with acute undifferentiated febrile illness in participating clinics in four countries in South America and to provide detailed epidemiological analysis of arbovirus infection in Iquitos, Peru, where more extensive monitoring was conducted.
  
  
  RESULTS
  A clinic-based syndromic surveillance system was implemented in 13 locations in Ecuador, Peru, Bolivia, and Paraguay. Serum samples and demographic information were collected from febrile participants reporting to local health clinics or hospitals. Acute-phase sera were tested for viral infection by immunofluorescence assay or RT-PCR, while acute- and convalescent-phase sera were tested for pathogen-specific IgM by ELISA. Between May 2000 and December 2007, 20,880 participants were included in the study, with evidence for recent arbovirus infection detected for 6,793 (32.5%). Dengue viruses (Flavivirus) were the most common arbovirus infections, totaling 26.0% of febrile episodes, with DENV-3 as the most common serotype. Alphavirus (Venezuelan equine encephalitis virus [VEEV] and Mayaro virus [MAYV]) and Orthobunyavirus (Oropouche virus [OROV], Group C viruses, and Guaroa virus) infections were both observed in approximately 3% of febrile episodes. In Iquitos, risk factors for VEEV and MAYV infection included being male and reporting to a rural (vs urban) clinic. In contrast, OROV infection was similar between sexes and type of clinic.
  
  
  CONCLUSIONS
  Our data provide a better understanding of the geographic range of arboviruses in South America and highlight the diversity of pathogens in circulation. These arboviruses are currently significant causes of human illness in endemic regions but also have potential for further expansion. Our data provide a basis for analyzing changes in their ecology and epidemiology.
authors: United States Naval Medical Research Center Detachment, Iquitos and Lima, Peru.
authors: Brett M
authors: BM
authors: Forshey
authors: Carolina
authors: C
authors: Guevara
authors: V Alberto
authors: VA
authors: Laguna-Torres
authors: Manuel
authors: M
authors: Cespedes
authors: Jorge
authors: J
authors: Vargas
authors: Alberto
authors: A
authors: Gianella
authors: Efrain
authors: E
authors: Vallejo
authors: César
authors: C
authors: Madrid
authors: Nicolas
authors: N
authors: Aguayo
authors: Eduardo
authors: E
authors: Gotuzzo
authors: Victor
authors: V
authors: Suarez
authors: Ana Maria
authors: AM
authors: Morales
authors: Luis
authors: L
authors: Beingolea
authors: Nora
authors: N
authors: Reyes
authors: Juan
authors: J
authors: Perez
authors: Monica
authors: M
authors: Negrete
authors: Claudio
authors: C
authors: Rocha
authors: Amy C
authors: AC
authors: Morrison
authors: Kevin L
authors: KL
authors: Russell
authors: Patrick J
authors: PJ
authors: Blair
authors: James G
authors: JG
authors: Olson
authors: Tadeusz J
authors: TJ
authors: Kochel
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood; D001102:Arbovirus Infections / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*; D001103:Arboviruses / Q000145:classification* / Q000302:isolation & purification; D002648:Child; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005335:Fever of Unknown Origin / Q000453:epidemiology* / Q000209:etiology*; D019085:Fluorescent Antibody Technique, Direct; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013020:South America / Q000453:epidemiology; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D007075:Immunoglobulin M