Table 1
Enterobiasis prevalence and distribution by age and sex, Varna District, NE Bulgaria, 2009 – 2018
| Age | Sex | Positive | Negative | Prevalence % (CI) | OR (CI) | p |
|---|---|---|---|---|---|---|
| Children | Female | 277 | 18 057 | 1.51 (1.23 – 1.83) | 1 | – |
| Children | Male | 289 | 19 263 | 1.48 (1.21 – 1.78) | 0.98# (0.74 – 1.29) | 0.80 |
| Children | Total | 566 | 37 320 | 1.49 (1.30 – 1.71) | 5.95* (4.05 – 8.73) | 2.2x10 – 16 |
| Adults | Female | 58 | 25 000 | 0.23 (0.14 – 0.35) | 1 | – |
| Adults | Male | 27 | 8 337 | 0.32 (0.16 – 0.58) | 1,40# (0.65 – 3.01) | 0.17 |
| Adults | Total | 85 | 33 337 | 0.25 (0.17 – 0.36) | 1 | |
| Total | Female | 335 | 43 057 | 0.77 (0.64 – 0.92) | 1 | – |
| Total | Male | 316 | 27 600 | 1.13 (0.94 – 1.36) | 1.47# (1.13 – 1.90) | 1.21x10 – 6 |
Fig. 1
Annual prevalence of enterobiasis in Varna District and Bulgaria, 2009 – 2018. Overall annual prevalence of enterobiasis in Varna district (blue line) compared to observed levels for the entire country (green dotted line). * Data from the official analyses of the NCIPD (Rajnova et al., 2018, 2019; Stoyanova, 2019).
Fig. 2
Annual dynamics of the prevalence of enterobiasis in children and adults in Varna District, NE Bulgaria, 2009 – 2018. The observed annual prevalence (labelled points) of enterobiasis in children (blue) and adults (green) is depicted within the exact Clopper-Pearson CI (error bars). The predictions of the binomial linear model and CI are presented by continuous lines and shaded areas correspondingly. The model confirms the observed significant 5 – 6-fold increase in the prevalence of enterobiasis in children during the observed period as compared to the relatively constant levels in adults.
Fig. 3
Average ten-year prevalence of enterobiasis distributed by age, Varna District, NE Bulgaria, 2009 – 2018.
Fig. 4
Average ten-year prevalence and odds ratio of enterobiasis in different age groups, Varna District, NE Bulgaria, 2009 – 2018. Average prevalence (columns; left axis) for the observed decade in adults and children 0 – 2, 2 – 6 and 7 – 18-year-old. Odds ratios comparing the relative risk of infection to the risk in the adult population are presented with labelled dots and projected on the right axis. Odds ratios significantly different from 1 are presented with a triangular shape.