Table 3.

Negative binomial multivariate models of the impact of targeted IRS with pirimiphos-methyl on An. funestus and An. gambiae counts per household within the areas targeted for spraying, using robust standard errors and generalized estimating equations clustered by household, N = 1,271

	An. funestus			An. gambiae
	IRR	95% CI	P-value	IRR	95% CI	P-value
Post-IRS	0.49	(0.29, 0.81)	0.005	0.64	(0.42, 0.96)	0.03
Open water source	–	–	–	1.41	(1.02, 1.95)	0.04
HH within 500 m (by 100 HH)	0.60	(0.51, 0.70)	< 0.001	0.81	(0.75, 0.88)	< 0.001
Elevation (by 10 m)	0.43	(0.33, 0.55)	< 0.001	–	–	–
Slope	0.82	(0.73, 0.92)	0.001	–	–	–
NDVI (by 10%)	1.29	(0.99, 1.66)	0.06	1.23	(1.00, 1.52)	0.05
Distance from Lake Mweru (1,000 in km)	1.12	(1.03, 1.21)	0.005	–	–	–
Distance from cat. 1 streams (in km)	0.55	(0.31, 0.98)	0.04	0.49	(0.34, 0.73)	< 0.001
Distance from cat. 4 streams (in km)	1.42	(1.18, 1.71)	< 0.001	–	–	–
Lagged rainfall (by 10 mm)*	0.24	(0.13, 0.47)	< 0.001	0.68	(0.47, 0.99)	0.05
Lagged rainfall (by 10 mm)†	–	–	–	3.96	(1.88, 8.37)	0.001
Lagged maximum temperature (in °C)‡	1.14	(1.03, 1.26)	0.01	–	–	–
Lagged maximum temperature (in °C)§	0.79	(0.66, 0.94)	0.007	–	–	–
Lagged maximum temperature (in °C)∥	–	–	–	0.79	(0.67, 0.92)	0.002
Lagged minimum temperature (in °C)∥	–	–	–	1.32	(1.18, 1.48)	< 0.001

An. funestus = Anopheles funestus; An. gambiae = Anopheles gambiae; HH = household; IRR = incidence rate ratio; IRS = indoor residual spraying; NDVI = normalized difference vegetation index.

^*Interval = 2 weeks, lag = 2 weeks.

^†Interval = 10 weeks, lag = 4 weeks.

^‡Interval = 1 week, lag = 2 weeks.

^§Interval = 8 weeks, lag = 3 weeks.

^∥Interval = 7 weeks, lag = 2 weeks.