title: Chikungunya Virus Infections Among Patients with Dengue-Like Illness at a Tertiary Care Hospital in the Philippines, 2012-2013.
abstract: Chikungunya virus (CHIKV) often co-circulates with dengue virus (DENV). A cross-sectional surveillance study was conducted at a tertiary hospital in Manila, Philippines, to describe the prevalence and characteristics of DENV and CHIKV infections among patients seeking care for dengue-like illness. Acute blood samples from patients ≥ 6 months of age clinically diagnosed with dengue from November 2012 to December 2013 underwent reverse transcription polymerase chain reaction (RT-PCR) to detect DENV and CHIKV RNA. A total of 118 patients with clinically diagnosed dengue (age range = 1-89 years, mean = 22 years; male-to-female ratio = 1.51) were tested by DENV RT-PCR; 40 (34%) were DENV PCR-positive (age range = 1-45 years, mean = 17 years). All DENV serotypes were detected: 11 (28%) DENV-1, 6 (15%) DENV-2, 6 (15%) DENV-3, and 17 (42%) DENV-4. Of 112 patients clinically diagnosed with dengue and tested by CHIKV RT-PCR, 11 (10%) were CHIKV PCR-positive (age range = 2-47 years, mean = 20.3 years). No coinfections were detected. Presenting signs/symptoms did not differ between DENV- and CHIKV-positive cases. Sequencing of envelope 1 gene from two CHIKV PCR-positive samples showed Asian genotype. This study highlights the potential for misdiagnosis of medically attended CHIKV infections as DENV infection and the difficulty in clinically differentiating dengue and chikungunya based on presenting signs/symptoms alone. This underscores the necessity for diagnostic laboratory tests to distinguish CHIKV infections in the background of actively co-circulating DENV.
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines velascojm@afrims.org.
authors.forename: John Mark
authors.initials: JM
authors.lastname: Velasco
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines.
authors.forename: Maria Theresa
authors.initials: MT
authors.lastname: Valderama
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines.
authors.forename: Maria Nila
authors.initials: MN
authors.lastname: Lopez
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines.
authors.forename: Domingo
authors.initials: D
authors.lastname: Chua
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines.
authors.forename: Rene
authors.initials: R
authors.lastname: Latog
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines.
authors.forename: Vito
authors.initials: V
authors.lastname: Roque
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines.
authors.forename: June
authors.initials: J
authors.lastname: Corpuz
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines.
authors.forename: Chonticha
authors.initials: C
authors.lastname: Klungthong
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines.
authors.forename: Prinyada
authors.initials: P
authors.lastname: Rodpradit
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines.
authors.forename: Kittinun
authors.initials: K
authors.lastname: Hussem
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines.
authors.forename: Yongyuth
authors.initials: Y
authors.lastname: Poolpanichupatam
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines.
authors.forename: Louis
authors.initials: L
authors.lastname: Macareo
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines.
authors.forename: Stefan
authors.initials: S
authors.lastname: Fernandez
authors.affiliation: Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; Armed Forces of the Philippines Medical Service School, Quezon City, Philippines; Department of Research and Training, Armed Forces of the Philippines Medical Center, Quezon City, Philippines; Epidemiology Bureau, Department of Health, Manila, Philippines.
authors.forename: In-Kyu
authors.initials: IK
authors.lastname: Yoon
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D065632:Chikungunya Fever / Q000175:diagnosis / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D060085:Coinfection / Q000453:epidemiology / Q000821:virology; D003430:Cross-Sectional Studies; D003715:Dengue / Q000175:diagnosis / Q000453:epidemiology*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D010679:Philippines / Q000453:epidemiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D062606:Tertiary Care Centers / Q000706:statistics & numerical data; D055815:Young Adult