Long-lasting control of Anopheles arabiensis by a single spray application of micro-encapsulated pirimiphos-methyl (Actellic® 300 CS)

Table 5 Estimated time (months) for mortality to decrease to 80 and 50% for Anopheles arabiensis dondotha (pyrethroid susceptible), tested on sprayed experimental hut walls (concrete and mud) and ceiling (thatch)

Insecticide	Substrate	Estimated time to 80% mortality		Estimated time to 50% mortality
Insecticide	Substrate	Time (months)	95% CI	Time (months)	95% CI
Hut walls
P-methyl EC	Mud	†	†	†	†
P-methyl CS B	Concrete	7.0	(5.4 to 8.3)	11.3	(10.2 to 12.4)
P-methyl CS B	Mud	4.8	(1.9 to 6.9)	11.4	(9.9 to 13.0)
P-methyl CS BM	Concrete	6.6	(3.0 to 9.0)	16.0	(13.5 to 20.6)
P-methyl CS BM	Mud	0.9	(† to 4.4)	9.0	(6.4 to 11.0)
Hut ceilings
P-methyl EC	Thatch	†	†	2.4	(† to 6.1)
P-methyl CS B	Thatch	8.4	(7.4 to 9.4)	12.0	(11.2 to 12.7)
P-methyl CS BM	Thatch	10.8	(9.9 to 11.7)	14.4	(13.7 to 15.2)

†Indicates that statistical models produced estimates outside the study period: in all cases estimates were lower than the specified mortality (50 or 80%, respectively) throughout the entire study period.

ISSN: 1475-2875