The feeding index concept introduced for analysis of host-feeding patterns of mosquitoes, may be defined as "the observed proportion of feeds on 1 host with respect to another divided by the expected comparative proportion of feeds on these 2 hosts, based on factors affecting feeding." The advantages of the feeding index are that (1) it departs from the inference that feeding patterns are attributable to host preference; (2) it does not require a full animal census which is often impracticable or even impossible; and (3) it draws attention to, and allows assessment of some of the multiple factors that influence feeding patterns.