Seroepidemiology of pertussis in Hangzhou, China, during 2009–2017

Figures & data

Figure 1. Epidemiology of pertussis IgG in population during the 9 years.

Table 1. Seroepidemiology of pertussis IgG in population among various groups via univariate analysis.

		Pertussis
Variable	Total (n)	Positive, n(%)	χ2,P	GMC (U/ml)	t/F,P
Gender			χ^2 = 9.02,P= .03		t = −2.86,P= .004
Male	1745	1179(67.6)		46.16
Female	1615	1168(72.3)		50.96
District			χ^2 = 16.54,P< .001		t = 14.871,P< .001
urban	1159	861(74.3)		52.91
rural	2201	1486(67.5)		46.12
Age (years)			χ^2 = 275.90,P< .001		F = 26.35,P< .001
0-	384	194(50.5)		30.65
1-	288	159(55.2)		35.56
2-	274	159(58.0)		40.7
3-	374	225(60.2)		35.9
5-	348	234(67.2)		44.69
7-	273	200(73.3)		50.82
10-	268	231(86.2)		65.46
15-	407	355(87.2)		68.58
20-	278	211(75.9)		51.54
30-	220	160(72.7)		48.39
40-	246	219(89.0)		66.66
Vaccination history			χ^2 = 41.69,P< .001		F = 13.69,P< .001
Yes	2001	1337(66.8)		45.23
No	174	104(59.8)		45.38
Unknown	1185	906(76.5)		54.38
Total	3360	2347(69.9)		48.46

Figure 2. Seroepidemiology of pertussis IgG in population by age groups.

Table 2. Association of Seroepidemiology of Pertussis IgG and related variables via multivariate analysis.

	Seropositivity of pertussis = y^a		GMC (U/ml) of pertussis = y^b
The independent variables	OR(95%CI)	P-values	OR(95%CI)	P-values
Vaccination history
No	1		1
Yes	2.957(1.998,4.377)	<0.001	11.719(4.124–19.313)	0.002
Unknown	2.904(1.886,4.469)	<0.001	15.914(7.618–24.209)	<0.001
Age (years)
0-	1		1
1-	1.304(0.947–1.797)	0.103	4.71(0.092–11.802)	0.193
2-	1.419(1.025–1.966)	0.035	10.24(3.045–17.435)	0.005
3-	1.396(1.035–1.882)	0.029	4.417(0.114–11.007)	0.189
5-	2.225(1.626–3.044)	<0.001	14.554(7.85–21.258)	<0.001
7-	3.161(2.225–4.492)	<0.001	20.388(13.191–27.585)	<0.001
10-	8.307(5.454–12.65)	<0.001	35.896(28.65–43.143)	<0.001
15-	9.441(6.403–13.92)	<0.001	39.238(32.581–45.896)	<0.001
20-	3.215(2.123–4.870)	<0.001	15.865(7.484–24.246)	<0.001
30-	2.785(1.797–4.317)	<0.001	12.953(4.006–21.9)	0.005
40-	9.277(5.568–15.45)	<0.001	31.658(23.027–40.289)	<0.001

^a:Logistic regression was used to analyze the associations between the changes of the rate of pertussis IgG seropositivity and the related factors.

^b:Linear regressionwas used to analyze the associations between the changes of the GMC levels of pertussisIgG and the related factors.