High frequency of pre-existing neutralizing antibody responses in patients with dengue during an outbreak in Central Brazil

Table 1 Characteristics of dengue patients by disease severity during outbreak in central Brazil

Characteristics	Severe dengue^a n = 40	Dengue n = 20	p ^b
Age, mean SD, years	33.6 ± 18.5	47.05 ± 20.5	<0.001
Sex, ratio of females to males	2.1:1.0	0.8:1.0
Educational level, years^c(%)
≤ 8	17(51.5)	7(41.2)	0.49
> 8	16(48.5)	10(58.8)
Race^d, (%)
White	18(48.7)	7(36.8)	0.46
Mixed/Black	19(51.3)	12(63.2)
Hospitalization, (%)	20(50.0)	3(15.0)	<0.01
Hemorrhagic manifestation, (%)	36(90.0)	6^e(30.0)	<0.01
Platelet count nadir, platelets/mm^3f
> 100	16(40.0)	15(75.0)	0.02
> 50 to ≤ 100	18(45.0)	5(25.0)
≤ 50	6(15.0)	-
Hematocrit increase, (%)
< 10	32(80.0)	13(65.0)	0.35
≥ 10	8(20.0)	7(35.0)
Albumin, (%)
< 3.5 – low values	19(47.5)	4(20.0)	0.04
3.5–5.5 – normal values	21(52.5)	16(80.0)
AST, (%)
< 50 – normal values	13(32.5)	12(60.0)	0.04
≥ 50 – high values	27(67.5)	8(40.0)
ALT, (%)
< 41 – normal values	18(45.0)	11(55.0)	0.46
≥ 41 – high values	22(55.0)	9(45.0)

Data are the no. (%) of subjects, unless otherwise indicated; AST aspartate aminotransferase, ALT alanine aminotransferase. Platelet count nadir was defined as the lowest platelet value obtained
^aClinically classified as dengue with warning signs or severe dengue
^b X ² test was used for categorical variables
^cData were missing for seven severe dengue cases and three dengue cases
^dData were missing for three severe dengue cases and one dengue case
^ePositive tourniquet test as the only hemorrhagic manifestation
^fThe platelet count nadir was defined as the lowest platelet value obtained

ISSN: 1471-2334