The transit phase of migration: circulation of malaria and its multidrug-resistant forms in Africa

Abstract

In the third article in a six-part <I>PLoS Medicine</I> series on Migration & Health, Cally Roper and Caroline Lynch use a case study of migration and anti-malarial drug resistance in Uganda to discuss the specific health risks and policy needs associated with the transit phase of migration.

Figure 1. Regions of malaria parasite exchange strongly resemble the distribution of resistance allele lineages.

(A) P. falciparum migration communities for Africa. The map shows communities connected by comparatively higher levels of malaria migration, with community membership shown by colour (from Tatem and Smith [13]). (B) The distribution of resistance mutant lineages among 20 African P falciparum populations (reprinted from Pearce et al. [14]). Most resistance mutations in the dhps gene belong to five major lineages, (indicated by the colours shown in the key) and each is derived from a single emergence event. Those which do not belong to the major five are shown in grey.

Figure 2. The complex patterns of migration flow in Uganda.

The area of highly drug-resistant malaria is shown in red, major population migration flows are shown by arrows, major refugee camps are hatched, and the major urban population in Kampala is indicated in pink. The permanent migration streams are estimated from birthplace data from 1969 population census from Goddard .