Prevalence of human leishmaniasis in Sudan: A systematic review and meta-analysis

Table 1 Main characteristics of studies included in the meta-analysis

Ref.	Sample size	Method	Type of leishmaniasis	Geographical location	Study design	Study setting	Prevalence n (%)
							Overall, n %	Male	Female
Hashim[24], 1997	126	PCR & LST	VL/CL	Central Sudan	CS	HB	43 (34.1)	NR	NR
El Dawi[25], 1994	44	DAT	VL	Central Sudan	PS	HB	19 (43.2)	NR	NR
Ibrahim[26], 2012	734	LST	CL	Central Sudan	CS	CB	73 (9.9)	NR	NR
Sharief et al[27], 2019	1781	DAT & LST	VL	Western Sudan	ES	CB	238 (13)	NR	NR
Osman[28], 2011	332	PCR	CL	Western Sudan	CS	CB	32 (9.6)	NR	NR
Noraldaim[29], 2012	110	DAT & ELISA	VL	Central Sudan	PS	CB	46 (41.8)	NR	NR
Mohamed et al[30], 2019	95	DAT	VL	Eastern Sudan	CS	CB	5 (5.3)	NR	NR
Dereure et al[31], 2003	79	Culture	VL	Eastern Sudan	NR	CB	23 (29.1)	NR	NR
EL-Safi et al[18], 2002	947	DAT & LST	VL	Eastern Sudan	CS	CB	132 (13.9)	NR	NR
El-Safi and Peters[32], 1991	9657	DAT	CL	Central Sudan	RS	HB	736 (7.6)	449 (61)	287 (39)
Atia[23], 2012	373	DAT	VL	Eastern Sudan	CS	CB	64 (17.2)	29 (45.3)	35 (54.7)
Abdallah[34], 2015	352	DAT & ELISA	VL	Eastern Sudan	PS	HB	71 (20.2)	43 (60.6)	28 (39.4)
Ebrahim[19], 2016	48972	Mixed	VL	Western Sudan	RS	HB	815 (1.7)	(62)	(38)
Awadalla[35], 2007	399	DAT	VL	Eastern Sudan	CS	CB	35 (8.8)	23 (65.7)	12 (34.3)
Muawyia et al[36], 2021	40	DAT	CL	Central Sudan	NR	HB	13 (32.5)	10 (76.9)	3 (23.1)
Osman et al[37], 2021	410	LST	CL	Northern Sudan	CS	CB	290 (70.7)	91 (31.4)	199 (68.6)
Abdullah et al[38], 2021	162443	Mixed	VL/CL	Western Sudan	RS	HB	7131 (4.4)	4657 (65.3)	2474 (34.7)
Ahmed[39], 2011	50	Mixed	VL	Central Sudan	CS	HB	NR	38 (76)	12 (24)
Ahmed[40], 2017	215	Mixed	VL	Eastern Sudan	R-CC	HB	NR	140 (65.1)	75 (34.9)
Collis et al[41], 2019	3801	LST	CL	Nationwide	RS	HB	NR	2178 (57.3)	1599 (42.1)

CB: Community-based study; CL: Cutaneous leishmaniasis; CS: Cross sectional study; DAT: Direct agglutination test; DS: Descriptive study; ELISA: Enzyme-linked immunosorbent assay; ES: Epidemiological surveys; HB: Hospital-based study; LST: Leishmania skin test; NR; Not reported; PCR: Polymerase chain reaction; PS: Prospective study; R-CC: Retrospective case-control study; RS: Retrospective study; VL: Visceral leishmaniasis.

Table 2 Heterogeneity related variables for the prevalence of human leishmaniasis in the current meta-analysis (based on meta regression)

Variables	Coefficient	SE	t	P > |t|	95%CI
Study yr/s	-0.0183371	0.0892299	-0.21	0.841	(-0.2171537, 0.1804794)
Sample size	-1.46e-06	1.10e-06	-1.33	0.204	(3.80e-06, 8.83e-07)
Diagnostic method	0.0152374	0.0500373	0.30	0.767	(-0.0962528, 0.1267275)
Type of leishmaniasis	-0.0271858	0.0653937	-0.42	0.686	(-0.172892, 0.1185204)
Study region	-0.0472426	0.0775729	-0.61	0.556	(-0.2200857, 0.1256005)
Study design	0.0029982	0.0584459	0.05	0.960	(-0.1272273, 0.1332237)
Study setting	-0.0381169	0.1762884	-0.22	0.833	(-0.4309118, 0.354678)

CI: Confidence interval.

Table 3 Subgroup analysis findings (random-effects model)

Analysis of leishmaniasis		Number of studies/pooled sample size	Pooled prevalence % (95%CI)	T2	I2%	H2	P value
Sex	Male	10/13218	60 (52-67)	0.01	97.96	49.09	< 0.001
	Female	10/13218	40 (33-48)	0.01	97.96	49.07	< 0.001
Age group	< 5	5/8326	3 (1-6)	0.001	99.99	18316.61	< 0.001
	5-14	5/8326	22 (12-32)	0.01	97.76	44.50	< 0.001
	15-44	5/8326	60 (50-69)	0.01	95.53	22.38	< 0.001
	≥ 45	5/8326	14 (9-19)	0.001	92.09	12.63	< 0.001
Types of human leishmaniasis	VL	10/53152	18 (10-27)	0.02	99.28	138.39	< 0.001
	CL	5/11173	26 (2-50)	0.07	99.79	485.11	< 0.001
	VL/CL	2/162569	19 (10-48)	0.04	97.98	49.48	< 0.001
Study region	Central Sudan	6/10711	27 (14-40)	0.02	98.86	87.63	< 0.001
	Eastern Sudan	6/2245	15(9-21)	0.01	93.84	16.23	< 0.001
	Northern Sudan	1/410	71(66-75)	-	-	-	-
	Western Sudan	4/213528	7 (2-12)	0.00	99.97	2882.28	< 0.001
Study yr/s	Before 2000	5/10853	24 (12-37)	0.02	98.8	83.02	< 0.001
	Between 2001 to 2010	4/922	24 (9-39)	0.02	96.83	31.54	< 0.001
	After 2011	8/215119	17 (1-32)	0.05	100	24190.74	< 0.001
Study setting	Hospital-based study	8/221713	20 (10-31)	0.02	99.99	11092.03	< 0.001
	Community-based study	9/5181	21 (7-35)	0.05	99.54	218.75	< 0.001

I² index for the degree of heterogeneity; T² measure of heterogeneity; CI: Confidence interval; CL: Cutaneous leishmaniasis; VL: Visceral leishmaniasis.