Comparison of vaccination strategies for the control of dog rabies in Machakos District, Kenya

Abstract

Demographic and epidemiological field data were u .ed in a deterministic model to describe dog rabies transmission in Machak os District, Kenya and to predict the impact of potential vaccination strategies for its control. The ba ic reproduction number (Ro) was e timated to be 2-44 (J '52-3•36,95 % confidence limit ). There were three key model prediction. The first was that a threshold dog density (Kr) of 4•5 dogs km 2 (3'8-5'2 dogs km ", 95 % confidence limits) was required to maintain transmis ion. The second was that the estimated annual vaccination rate of 24 % failed to decrea incidence and actually increased the stability of transmission and may be counter-productive. Thirdly, to control rabies, it was predicted that S9 % (34 %-70 %, 9S % confidence limits) of dogs should be vaccinated at anyone time. This require approximately 70 % coverage for annual but only 60 % coverage for erni-annual vaccination campaign. Community-level vaccination trials are needed to test these predictions.