CHAPTER EIGHT 334 TABLE 8-14. PREVALENCE, ESTIMATED NUMBER OF CASES, AND DISTRIBUTION BY REGION, ACTIVE XEROPHTHALMIA (AND BITOT'S SPOTS), CHILDREN UNDER AGE 6, DECEMBER-APRIL (NBS 1981) Estimated Number of Children Affected Prevalence per 100 Children Percentage of Nepal's Total Sample N Region 1,833 2,189 1,345 1,047 790 7,204 376 5,863 (4,781) 9,119 (6,668) 1,918 (1,282) 1,636 (1,033) 2,322 (1,770) 20,858 (15,534) NA (OJ 0.9 (0.8) 1.2 (0.8) 0.4 (0.3) 0.5 (0.3) 0.9 (0.6) 0.8 (0.6) NA (NA) 28.1 (30.8) 43."/ (42.9) 9.2 (8.3) 7.9 (6.6) 11.1 (11.4) 100.0 (100.0) NA (NA) Eastern Central Western Far West A Far West B Subtotal Missing data Total 7,580 20,858 (15,534) 0.8 (0.6) 100.0 (100.0) Source: FRS.002 AN.77, 87 M Note: Figures in parentheses refer to the estimated number of cases, prevalence, and distribution of cases of active xerophthalmia that are Bitot's spots (XlB). Narayani is mostly terai, while Sagarmatha and the other zones in the east cut across all three terrains from plains to mountains. High prevalence rates of Bitot's spots are also found in the Far West zones of Mahakali and Rapti, each with a prevalence rate of 0.8 percent. Janakpur zone also has both a high Bitot's spot preva- lence (0.7%) and a significant share of all Bitot's spots in Nepal (11.3%). Sampling Strata: The distribution of xerophthalmia and Bitot's spots by survey sampling strata is shown in Table 8-16. The strata with the highest prevalence rates of Bitot's spots are the Eastern and Central Terai, each with a prevalence in excess of 1 percent. Nearly two-thirds of all Bitot's spots (66.l %) are found in these two strata. Other strata that exceed the WHO criterion of 0.5 percent include the Far Western Hills and the urban sites. The Western Terai is borderline (0.5% prevalence of Bitot's spots). 8.5.4 Community Characteristics Nepal has a complex array of community, religious, ethnic, and lan- guage groups, which may be relevant to the epidemiology of xerophthalmia. Just as disease foci may be found when looking at the geographic distribution of xerophthalmia, so high risk com-
