Fig 1.
The brown coloured areas represent the districts included in the study with the dates of vaccination campaigns and the level of endemicity (cases/100,000 population in 2004–6).
The percentage of participants seropositive for JEV and DENV are also shown, along with the number (%) JEV IgM positive, and the altitude range of the district.
Fig 2.
Recruitment process of participants in the three Nepali districts of Rupandehi, Banke and Udayapur.
In each district, recruitment was conducted in three Village Development Committees (VDC, bottom boxes), selected at random (see methods). Recruitment numbers in each VDC are indicated.
Table 1.
Demographic characteristics of participants overall and by district: N (%; 95% CI).
*median (range).
Fig 3.
JEV IgM ELISA results by district.
A, percentage and numbers of participants with anti-JEV IgM in each district, with 95% confidence intervals. B, JEV IgM ELISA values by district of the anti-JEV IgM log10 immune status ratio (ISR, the ratio of optical density readings obtained for the JEV and normal cell antigens for each sample). Thick bars represent the median, boxes the interquartile range, error bars 1.5x the IQR, and outliers are shown as open circles.
Fig 4.
Seroprevalence of JEV and DENV antibody by 50% plaque reduction neutralisation titre (PRNT50).
Data are the percentage of participants with PRNT50 ≥1:10, error bars indicate the 95% confidence interval.
Table 2.
Sensitivity, specify, positive and negative predictive values of anti-JEV and anti-DENV ELISAs using PRNT as the reference test.
Data are shown for IgG and IgM combined (as both can contribute to neutralisation), and for the IgG ELISA alone (for use in sero-surveys).
Fig 5.
A geometric mean (error bar: 95% confidence interval) of JEV and DENV serotypes 1–4 neutralising titres in the three districts.
B Relationship between DENV and JEV neutralising titres (PRNT50) for each of the four DENV serotypes. Samples with PRNT50 ≤ 1:10 have been assigned a value of 1 for the purpose of plotting these data. Spearman’s R and p values are shown for each DENV serotype.
Table 3.
Factors independently associated with an anti-JEV PRNT50 ≥1:10 (n = 938).
Table 4.
Factors independently associated with an anti-DENV PRNT50 ≥1:10 (n = 938).