Biology Reference
In-Depth Information
Figure 1.3, cont'd
health records is more sensitive at low parasite prevalence values, but is
biased. For example, we do not know the proportion of people within every
district who do not seek care for malaria at a public health facility and are
therefore missed by the statistics. We used clinical incidence data to define
the areas where we know very little, other than that malaria exists but is
so low as to be essentially unquantifiable using available data. We referred
to this level of risk as unstable malaria transmission and defined it as less
than one case per 10,000 people per year (or <0.1 API). At very low lev-
els of incidence, a small change is proportionally large so API is measured
across an administrative (ADMIN) division and we averaged this figure over
4 years (providing data are available).
