Seroprevalence rates of poliovirus antibodies

The information is intended to provide an indication of population immunity, based on antibody testing results in serum specimens received during the designated year.

Percentage of specimens with poliovirus type 1 antibody

Year	Age group
	1-10		11-20		21-30		≥31
	No tested	%	No tested	%	No tested	%	No tested	%
1990	100	98	100	98	100	79	100	77
1995	100	99	100	98	100	89	100	93
2000	100	99	100	96	100	92	100	76
2005	100	100	100	99	100	98	100	93
2008*	250	100	100	99	-	-	-	-
2010	100	99	100	99	100	100	100	95
2015	100	98	100	100	100	94	100	90
2020	100	97	100	99	100	99	100	91

Percentage of specimens with poliovirus type 2 antibody^#

Year	Age group
	1-10		11-20		21-30		≥31
	No tested	%	No tested	%	No tested	%	No tested	%
1990	100	96	100	97	100	89	100	85
1995	100	100	100	95	100	91	100	92
2000	100	99	100	99	100	95	100	85
2005	100	100	100	99	100	100	100	94
2008*	250	100	100	98	-	-	-	-
2010	100	100	100	100	100	100	100	94

Percentage of specimens with poliovirus type 3 antibody

Year	Age group
	1-10		11-20		21-30		≥31
	No tested	%	No tested	%	No tested	%	No tested	%
1990	100	96	100	95	100	89	100	86
1995	100	96	100	87	100	80	100	84
2000	100	97	100	77	100	77	100	67
2005	100	99	100	98	100	93	100	84
2008*	250	96.8	100	94	-	-	-	-
2010	100	95	100	93	100	83	100	89
2015	100	97	100	95	100	87	100	82
2020	100	92	100	97	100	89	100	75

Percentage of specimens with no antibody to all 3 types (to type 1 and 3 from 2015 data onwards^#) of poliovirus

Year	Age group
	1-10		11-20		21-30		≥31
	No tested	%	No tested	%	No tested	%	No tested	%
1990	100	1	100	0	100	6	100	5
1995	100	0	100	0	100	2	100	2
2000	100	0	100	0	100	1	100	3
2005	100	0	100	0	100	0	100	1
2008*	250	0	100	0	-	-	-	-
2010	100	0	100	0	100	0	100	0
2015	100	1	100	0	100	2	100	3
2020	100	1	100	0	100	0	100	7

*Inactivated polio vaccine (IPV) has replaced oral polio vaccine (OPV) for universal childhood vaccination in Hong Kong since February 2007.

^#Cessation of testing on poliovirus type 2 antibody since the World Health Organization announced limitation on handling live type 2 poliovirus in 2016.