An approach to estimate the influence of the treatment-type controls on the basic reproduction number, R-0, is proposed and elaborated. The presented approach allows one to estimate the effect of a given treatment strategy or to compare a number of different treatment strategies on the basic reproduction number. All our results are valid for sufficiently small values of the control. However, in many cases it is possible to extend this analysis to larger values of the control as was illustrated by examples. (C) 2018 Elsevier Ltd. All rights reserved.