Etiology of acute undifferentiated febrile illness in the Amazon basin of Ecuador.
We conducted a longitudinal observational study of 533 patients presenting to two hospitals in the Ecuadorean Amazon basin with acute undifferentiated febrile illness (AUFI) from 2001 through 2004. Viral isolation, reverse transcription-polymerase chain reaction (RT-PCR), IgM seroconversion, and malaria smears identified pathogens responsible for fever in 122 (40.1%) of 304 patients who provided both acute and convalescent blood samples. Leptospirosis was found in 40 (13.2%), malaria in 38 (12.5%), rickettsioses in 18 (5.9%), dengue fever in 16 (5.3%), Q fever in 15 (4.9%), brucellosis in 4 (1.3%), Ilhéus infection in 3 (1.0%), and Venezuelan equine encephalitis (VEE), Oropouche, and St. Louis encephalitis virus infections in less than 1% of these patients. Viral isolation and RT-PCR on another 229 participants who provided only acute samples identified 3 cases of dengue fever, 2 of VEE, and 1 of Ilhéus. None of these pathogens, except for malaria, had previously been detected in the study area.
Manock
Stephen R
SR
Rural Medical Services, Parrottsville, Tennessee 37843, USA. stevemanock@yahoo.com
Jacobsen
Kathryn H
KH
de Bravo
Narcisa Brito
NB
Russell
Kevin L
KL
Negrete
Monica
M
Olson
James G
JG
Sanchez
José L
JL
Blair
Patrick J
PJ
Smalligan
Roger D
RD
Quist
Brad K
BK
Espín
Juan Freire
JF
Espinoza
Willan R
WR
MacCormick
Fiona
F
Fleming
Lila C
LC
Kochel
Tadeusz
T
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003715:Dengue / Q000503:physiopathology; D005334:Fever / Q000209:etiology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007922:Leptospirosis / Q000503:physiopathology; D008137:Longitudinal Studies; D008288:Malaria / Q000503:physiopathology; D008875:Middle Aged; D011778:Q Fever / Q000503:physiopathology