The impact of indoor residual spraying on malaria incidence in East Shoa Zone, Ethiopia

Figures & data

Table 1. Number of unit structures sprayed and percentage of unit structures and population covered by spraying in 2001 and 2002

Village	Year of spraying
	2001				2002
	Total unit structures*	Sprayed	% Sprayed	% Population covered	Total unit structures	Sprayed	% Sprayed	% Population covered
Alge	625	607	90	94	651	604	93	97
Babo-Gaya	657	646	98	97	794	744	94	97
Ful-xino	396	395	99.9	99.9	435	421	97	95
Godety	308	290	94	95	327	312	95	96
Harewa	174	169	97	98	180	176	98	99
Sardo	393	376	96	99	393	370	94	96
Dalota-Gote	511	485	95	96	714	652	91	98
Kality	391	381	97	99.9	425	399	94	92
Delo	586	571	97	99.9	596	561	94	92
Dambi-1	544	515	92	96	347	305	88	98
Dambi-2	343	319	93	98	577	540	94	97
Ganda gorba	212	194	92	94	218	203	93	97
Denema	437	411	94	96	445	417	94	96
Yatu	341	339	99	99	323	306	95	94
Wajitu	605	596	99	99	695	672	97	96
Dukam Koticha	502	462	92	95	513	482	94	96
Dibdibe	408	404	99	99	417	400	96	95
Godino	810	769	95	97	995	852	96	97
Borer Tina	382	368	96	99	467	451	96	97
Borer Guda	283	273	96	98	347	335	96	98
Kurkura-1	450	439	98	98	-	-	-	-
Kurkura-2	328	312	95	96	-	-	-	-
Koftu	-	-	-	-	630	591	94	98
Kata wara-ganu	-	-	-	-	583	540	93	94

*Unit structure in malaria vector control context in Ethiopia includes human dwellings and other homesteads found in human compound.

Table 2. Comparison of the incidence of malaria before and after DDT spraying, for intervention and control villages

Village	Disease	Before intervention		After intervention
		n	% Total (PF, PV)	n	% Total (PF, PV)	OR (95% CI)	p-value
Alge	Yes	231	13.6 (8, 5.6)	161	9.2 (5.1, 4.1)	0.30 (0.25–0.37)	<0.001
	No	1,470	86.4	1,590	90.8
Bagaya	Yes	131	7.7 (3.2, 4.5)	83	4.7 (1.3, 3.4)	0.37 (0.29–0.46)	<0.001
	No	1,573	92.3	1,675	95.3
Dibdibe	Yes	146	10.8 (6, 4.8)	51	5.1 (2.7, 2.4)	0.52 (0.43–0.62)	<0.001
	No	880	89.2	942	94.9
Dal-gote	Yes	298	31.7 (11.1, 20.7)	234	24.4 (16.5, 7.9)	0.22 (0.17–0.27)	<0.001
	No	643	68.3	726	75.6
D/koti	Yes	120	10.2 (6.3, 3.9)	72	5.9 (1.9, 4)	0.40 (0.32–0.50)	<0.001
	No	1,055	89.8	1,147	94.1
Dalo	Yes	235	16.5 (10, 6.5)	167	11.4 (7.6, 3.9)	0.29 (0.23–0.35)	<0.001
	No	1,191	83.5	1,302	88.6
Dambi	Yes	109	8.7 (2.6, 6.0)	66	5.1 (1.2, 3.9)	0.39 (0.31–0.50)	<0.001
	No	1,149	91.3	1,232	94.9
Dambo	Yes	65	10 (6.3, 3.7)	36	5.4 (3.5, 2)	0.45 (0.34–0.39)	<0.001
	No	583	90	628	94.6
Dhanama	Yes	55	4.2 (1.6, 2.6)	26	2 (0.5, 1.4)	0.53 (0.41–0.68)	<0.001
	No	1,255	48	1,303	98
Fulxino	Yes	85	8.1 (3.2, 4.8)	41	3.8 (0.7, 3.2)	0.52 (0.42–64)	<0.001
	No	968	91.9	1,042	96.2
Godety	Yes	309	40.4 (12.2, 28.2)	246	30.8 (9.5, 21.3)	0.20 (0.16–0.25)	<0.001
	No	456	59.6	554	69.3
G/Garba	Yes	88	9.9 (5.6, 4.3)	49	5.3 (2.7, 2.6)	0.44 (0.35–0.56)	<0.001
	No	804	90.1	879	94.7
Godino	Yes	106	4.3 (2.2, 2.1)	66	2.7 (1.3, 1.4)	0.38 (0.30–0.48)	<0.001
	No	2,344	95.7	2,406	97.3
Harawa	Yes	42	5.5 (2.6, 2.9)	17	2.2 (0.8, 1.4)	0.60 (0.46–0.76)	<0.001
	No	727	94.5	771	97.8
Oftu	Yes	70	7.6 (2.5, 5.1)	37	3.6 (0.7, 2.9)	0.47 (0.37–0.60)	<0.001
	No	850	92.4	988	96.4
Sardo	Yes	283	25.2 (13.5, 11.8)	209	18.2 (9.5, 8.7)	0.26 (0.22–0.32)	<0.001
	No	838	74.8	938	81.8
Wajitu	Yes	73	4 (1.8, 2.2)	45	2.4 (0.8, 1.6)	0.34 (0.29–0.51)	<0.001
	No	1,739	96	1,798	97.6
Yatu	Yes	64	6.5 (2.9, 3.7)	25	2.5 (0.5, 2)	0.61 (0.50–0.74)	<0.001
	No	916	93.5	991	97.5
Kaliti	Yes	152	13.4 (5.5, 7.8)	91	7.8 (2.8, 4.9)	0.40 (0.33–0.49)	<0.001
	No	986	86.6	1,083	92.2
B Guda	Yes	89	8.2 (4.4, 3.8)	50	4.5 (2.6, 1.9)	0.44 (0.35–0.55)	<0.001
	No	1,000	91.8	1,066	95.5
Borartina	Yes	169	11.5 (2.8, 8.6)	75	5 (1.8, 3.2)	0.57 (0.49–0.64)	<0.001
	No	1,306	88.5	1,430	95
K/W/ganu	Yes	168	23.9 (8.5, 15.4)	116	15.6 (5.7, 10)	0.31 (0.25–0.39)	<0.001
	No	534	76.1	626	84.4

Parameters are obtained from Poisson regression model.

Table 3. Comparison of the incidence of malaria in DDT sprayed (intervention) vs. non-sprayed (control) villages

Village	Disease	Intervention		Control
		n	% Total (PF, PV)	n	% Total (PF, PV)	OR (95% CI)	p-value
Alge	Yes	161	9.2 (5.1, 4.1)	274	14.8 (6.8, 8)	0.41 (0.36–0.48)	<0.001
	No	1,590	90.8	1,576	85.2
Bagaya	Yes	83	4.7 (1.3, 3.4)	112	6.6 (2.5, 4.1)	0.32 (0.25–0.41)	<0.001
	No	1,675	95.3	1,735	93.4
Dibdibe	Yes	51	5.1 (2.7, 2.4)	159	15.2 (5.5, 9.6)	0.68 (0.61–0.76)	<0.001
	No	942	94.9	890	84.8
Dal-gote	Yes	234	24.4 (7.9, 16.5)	377	34.2 (11.2, 23)	0.33 (0.28–0.38)	<0.001
	No	726	75.6	667	65.8
D/koti	Yes	62	5.9 (1.9, 4.)	171	13.3 (5, 8.3)	0–58 (0.51–0.66)	<0.001
	No	1,147	94.1	1,117	86.7
Dalo	Yes	168	11.4 (3.9, 7.6)	178	11.5 (3.9, 7.5)	0.06 (0.03–0.10)	<0.001
	No	1,302	88.6	1,375	88.5
Dambi	Yes	66	5.1 (1.2, 3.9)	112	8.2 (2.3, 5.9)	o.41 (0.33–0.51)	<0.001
	No	1,232	94.9	1,260	91.8
Dambo	Yes	46	5.4 (2, 3.5)	76	10.8 (2.4, 8.4)	0.53 (0.43–0.65)	<0.001
	No	628	94.6	625	89.2
Dhanama	Yes	26	2 (0.5, 1.4)	23	1.6 (1.1, 0.6)	435 (140–1,348)	<0.001
	No	1,303	98	1,382	98.4
Fulxino	Yes	41	3.8 (0.7, 3.2)	150	13.3 (5.2, 8.1)	0.73 (0.66–0.80)	<0.001
	No	1,027	96.2	978	86.7
Godety	Yes	146	30.8 (9.5, 21.3)	149	17.6 (5, 12.6)	6.7 (5.6–8.01)	<0.001
	No	554	69.3	697	82.4
G/Garba	Yes	49	5.3 (2.7, 2.6)	143	14.6 (5.6, 9.0)	0.66 (0.58–0.74)	<0.001
	No	879	94.7	837	85.4
Godino	Yes	66	2.7 (1.3, 1.4)	107	4.1 (1.3, 2.8)	0.38 (0.30–0.49)	<0.001
	No	2,409	97.3	2,509	95.9
Harawa	Yes	17	2.2 (0.8, 1.4)	43	5.2 (2.6, 2.5)	0.61 (0.48–0.77)	<0.001
	No	771	97.8	789	94.8
Oftu	Yes	37	3.6 (0.7, 2.9)	34	3.1 (0.6, 2.6)	330 (106–1,022)	<0.001
	No	988	96.4	1,049	96.9
Sardo	Yes	209	18.2 (9.5, 8.7)	241	19.9 (7.1, 12.8)	0.13 (0.10–0.18)	<0.001
	No	938	81.8	971	80.1
Wajitu	Yes	45	2.4 (0.8, 1.6)	92	4.7 (2.7, 2)	0.51 (0.42–0.62)	<0.001
	No	1,798	97.6	1,855	95.3
Yatu	Yes	25	2.5 (0.5, 2)	37	3.4 (1.3, 2.1)	0.32 (0.20–0.52)	<0.001
	No	991	97.5	1,037	96.6
Kaliti	Yes	91	7.8 (2.8, 4.9)	221	18.1 (6.2, 11.9)	0.60 (0.51–0.66)	<0.001
	No	1,083	92.2	1,046	81.9
B Guda	Yes	50	4.5 (2.6, 1.9)	42	3.6 (1.4, 2.1)	134 (67–267)	<0.001
	No	1,066	95.5	1,137	96.4
Borartina	Yes	75	5 (1.8, 3.2)	166	10.4 (4.3, 6.4)	0.55 (0.48–0.63)	<0.001
	No	1,430	95	1,425	89.6
K/W/ganu	Yes	116	15.6 (5.7, 10)	238	30.4 (15.4, 14.9)	0.51 (0.45–0.58)	<0.001
	No	626	84.4	546	69.6
Total	Yes	1,964	6.8	3,129	9.9	0.37 (0.37–0.39)	<0.001
	no	27,068	93.2	28,602	90.1

Parameters are obtained from Poisson regression model.