Figure 1.
Flowchart of clinical and laboratory protocols for study participants in the Pediatric Dengue Cohort Study.
Of the 1,974 episodes of febrile illness in the Pediatric Dengue Cohort Study from August 2004 to June 2009 that met the WHO classification criteria for suspected dengue or were diagnosed with undifferentiated fever, 405 patients presented with febrile illness on 2 occasions, 105 presented on 3 occasions, 21 presented on 4 occasions, and 5 presented on 5 occasions. One patient presented after day 8 of illness and was excluded from analysis. Twenty-nine patients had cause of fever identified later in the course of illness. CBC, complete blood count; WHO, World Health Organization; UTI, urinary tract infection.
Table 1.
Definitions of clinical terminology, variables and disease classifications.
Figure 2.
Frequency of dengue-positive episodes that met the WHO classification criteria for suspected dengue by age (n = 181).
Upon presentation to the health center or hospital, children with a febrile illness were classified according to whether or not they met the WHO classification criteria for suspected dengue. One patient had two dengue virus infections over the course of the study and is represented twice. n = 6 for age 2, n = 10 for age 3, n = 18 for age 4, n = 23 for age 5, n = 21 for age 6, n = 16 for age 7, n = 21 for age 8, n = 23 for age 9, n = 24 for age 10, n = 19 for age 11+. Chi-square test for trend 5.977, p = 0.01. WHO, World Health Organization.
Table 2.
Characteristics of study participants by dengue testing results and disease severity (n = 1,974).
Figure 3.
Frequency of signs and symptoms by day in patients with OFI, DF and severe dengue.
Over the course of an episode of febrile illness, signs and symptoms were observed by medical personnel or reported by children and/or their parent/guardian. Selected signs and symptoms are shown here. A, Petechiae; OFI versus DF: chi-square test for trend 21.313, p<0.0001; day 1, n = 606; day 2, n = 1,243; day 3, n = 1,066; day 4, n = 876; day 5, n = 675; day 6, n = 481; day 7, n = 291; day 8, n = 175; B, Platelet count ≤150,000 cells/mm3; OFI versus DF: chi-square test for trend 14.928, p = 0.0001; day 1, n = 604; day 2, n = 970; day 3, n = 615; day 4, n = 568; day 5, n = 348; day 6, n = 234; day 7, n = 122; day 8, n = 65; C, Myalgia/arthralgia; OFI versus DF: chi-square test for trend 4.569, p = 0.03; day 1, n = 612; day 2, n = 1,253; day 3, n = 1,075; day 4, n = 877; day 5, n = 671; day 6, n = 477; day 7, n = 289; day 8, n = 181; D, Leukopenia; OFI versus DF: chi-square test for trend 6.449, p = 0.01; day 1, n = 604; day 2, n = 971; day 3, n = 615; day 4, n = 568; day 5, n = 348; day 6, n = 234; day 7, n = 122; day 8, n = 65; E, Positive tourniquet test; OFI versus DF: chi-square test for trend 20.124, p<0.0001; day 1, n = 256; day 2, n = 496; day 3, n = 402; day 4, n = 308; day 5, n = 202; day 6, n = 156; day 7, n = 78; day 8, n = 38; F, Abdominal pain; OFI versus DF: chi-square test for trend 9.149, p = 0.002; DF versus severe dengue: chi-square test for trend 4.127, p = 0.04; day 1, n = 609; day 2, n = 1,245; day 3, n = 1,066; day 4, n = 877; day 5, n = 675; day 6, n = 482; day 7, n = 290; day 8, n = 174; All other chi-square tests for trend comparing DF to severe dengue were non-significant. OFI, other febrile illness; DF, dengue fever; Severe dengue = dengue hemorrhagic fever, dengue shock syndrome, dengue with signs associated with shock, or dengue fever with compensated shock. Leukopenia is defined as WBC ≤5000 cells/mm3 and positive tourniquet test is defined as ≥10 petechiae/in2.
Table 3.
Signs and symptoms associated with testing DENV-positive among patients using generalized estimating equation models.