Table 2.

Individual SRLV prevalence in each continent. Data extracted from scientific literature published from 1981 to 2020.

Continent	Studies	N 1	Prevalence (%)		Range (%)		Heterogeneity	Refs
			Mean	CI 95% 2	Min	Max	I2 3 (p Value)
Africa	5	1688	16.65	14.95–18.50	1.37	24.80	98.09 (<0.001)	[19,20,21,22]
Asia	47	8309	20.38	19.52–21.26	0.00	71.20	98.60 (<0.001)	[23,24,25,26,27,28,29,30,31,32,33,34,35]
Europe	65	407,509	40.90	40.75–41.05	0.00	66.43	98.98 (<0.001)	[11,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56]
North America	46	124,542	21.76	21.53–21.99	0.00	52.00	99.61 (<0.001)	[57,58,59,60,61,62,63,64,65,66]
South and Central America	41	46,418	1.67	1.56–1.79	0.00	30.00	91.52 (<0.001)	[67,68,69,70,71,72,73,74,75]
Global	204	588,466	33.39	33.27–33.51	0.00	71.20	99.95 (<0.001)

¹ N, number of animals tested; ² CI 95%, 95% confidence interval; ³ I², heterogeneity statistic.