Skip to main content

Table 1 Demographic characteristics of the study participants (N = 801)

From: Prevalence of Zika virus neutralizing antibodies in healthy adults in Vietnam during and after the Zika virus epidemic season: a longitudinal population-based survey

Variables nZIKV IgM positive (%)Crude OR (95% CI)P-valueDENV IgG positive (%) (n = 83)Anti-ZIKV NS1 IgG positive (%) (n = 88)PRNT50 positive to ZIKV (%)
Age group (years)≤158711 (12.6)1.00 (Reference)0.054/11 (36.3)3/11 (27.3)2/87 (2.3)
16–3029519 (6.4)0.48 (0.22–1.04)9/19 (47.4)3/21 (14.3)3/295 (1.0)
31–4524131 (12.8)1.02 (0.49–2.13)18/31 (58.1)7/32 (21.9)3/241 (1.2)
46–6012718 (14.2)1.14 (0.51–2.55)14/18 (77.8)4/18 (22.2)1/127 (0.8)
≥60353 (8.5)0.65 (0.17–2.48)3/3 (100)1/5 (20)3/35 (8.6)
NAa161 (6.3) 1/1 (100)1/1 (100)1/16 (6.3)
SexFemale59059 (10)1.00 (Reference)0.5732/59 (54.2)10/64 (15.6)7/590 (1.2)
Male21124 (11.4)1.15 (0.7–1.91)17/24 (70.8)9/24 (37.5)6/211 (2.8)
EthnicityEde29025 (8.6)1.00 (Reference)0.1615/25 (60.0)5/26 (19.2)3/290 (1.0)
Kinh50358 (11.5)1.42 (0.87–2.33)34/58 (58.6)14/62(22.6)10/503 (2.0)
Otherb80   0/8 (0.0)
Pregnancy 661 (1.5)  0/1(0.0)0/1(0.0)0/66 (0.0)
  1. CI confidence interval, DENV dengue virus, IgG immunoglobulin G, IgM immunoglobulin M, NA not available, OR odds ratio, ZIKV Zika virus, ssIKV NS1 IgG positive, ZIKV antibodies were determined using anti-ZIKV NS1 IgG ELISA (P/N ratio ≥ 2); PRNT50 positive to ZIKV was defined as plaque-reduction neutralization test titers with a ≥ 50% reduction in ZIKV plaque-forming units at a serum dilution of ≥1:20
  2. a Participants with missing information on age were excluded from the multivariate logistic regression analysis
  3. b Participants whose ethnicity was categorized as “Other” were combined with the “Ede” ethnic group in the multivariate logistic regression analysis