Table 1. Incidence density rate (IDR) of positive animal-month at risk for Cercopithifilaria bainae-infected dogs throughout the study period.

Sampling time	Number of dogs*	Number of new cases	Dog-months of follow-up	IDR
Baseline (March-May 2011)	58	0	–	–
July 2011	58	2	174	1.1
September 2011	53	0	106	0
November 2011	52	4	104	3.8
April 2012	51	4	255	1.5
October 2012	48	5	288	1.7

^*These numbers represent the negative dogs that have been included in the cohort for calculating the IDR at each sampling time.