Rubella seroprevalence among mothers and incidence of congenital rubella three years after rubella vaccine introduction in Vietnam

Figures & data

Table 1. Rubella seronegativity in each characteristic of mothers and babies

Characteristics			All Number (%)	Seronegative Number (%)	Odds ratio (95%CI)	Adjusted odds ratio* (95%CI)
			n = 2013	n = 410
Mothers
	Age group
		18–19	53 (2.6)	10 (2.4)	1.18 (0.57–2.43)
		20–24	382 (19.0)	104 (25.4)	1.89 (1.38–2.60)
		25–29	785 (39.0)	165 (40.2)	1.35 (1.02–1.79)
		30–34	564 (28.0)	93 (22.7)	reference
		35–39	193 (9.6)	34 (8.3)	1.08 (0.70–1.67)
		40–46	36 (1.8)	4 (1.0)	0.63 (0.22–1.83)
	Maternal education
		No school/primary	136 (6.8)	29 (7.1)	reference	reference
		Secondary	470 (23.4)	112 (27.3)	1.15 (0.73–1.83)	1.05 (0.66–1.67)
		High school	506 (25.1)	113 (27.6)	1.06 (0.67–1.68)	0.95 (0.60–1.52)
		College/university	901 (44.8)	156 (38.1)	0.77 (0.50–1.21)	0.72 (0.46–1.13)
	Maternal occupation
		Unemployed/house-wife	536 (26.6)	120 (29.3)	reference	reference
		Farmer/fishery/un-skilled worker	443 (22)	95 (23.2)	0.95 (0.70–1.28)	1.00 (0.74–1.36)
		Office worker/skilled worker	862 (42.8)	169 (41.2)	0.85 (0.65–1.10)	0.91 (0.69–1.19)
		Owner/professional	134 (6.7)	20 (4.9)	0.61 (0.36–1.02)	0.73 (0.43–1.24)
		Other	38 (1.9)	6 (1.5)	0.65 (0.27–1.59)	0.69 (0.28–1.69)
	Rubella vaccination history
		Yes	253 (12.6)	12 (2.9)	reference	reference
		No	1737 (86.3)	395 (96.3)	5.91 (3.28–10.67)	5.85 (3.24–10.58)
		Unknown	23 (1.1)	3 (0.7)	3.01 (0.78–11.56)	3.11 (0.81–11.99)
	Residential area
		Urban	1199 (59.6)	240 (58.5)	0.95 (0.76–1.18)	0.96 (0.77–1.20)
		Rural	814 (40.4)	170 (41.5)	reference	reference
	Para
		Primipara	827 (41.1)	162 (39.5)	0.92 (0.74–1.15)	0.72 (0.56–0.92)
		Multipara	1186 (58.9)	248 (60.5)	reference	reference
	Number of antenatal care visit
		0–3	72 (3.6)	17 (4.2)	reference	reference
		4–6	189 (9.4)	51 (12.4)	1.2 (0.64–2.25)	1.20 (0.64–2.27)
		7–9	605 (30.1)	118 (28.8)	0.78 (0.44–1.40)	0.77 (0.43–1.39)
		10 or more	1147 (57)	224 (54.6)	0.79 (0.45–1.38)	0.79 (0.44–1.39)
	Mode of delivery
		Cesarean section	836 (41.5)	178 (43.4)	1.10 (0.89–1.37)	1.20 (0.96–1.50)
		Vaginal delivery	1177 (58.5)	232 (56.6)	reference	reference
Neonates
	Sex
		Boys	1057 (52.5)	218 (53.2)	reference	reference
		Girls	956 (47.5)	192 (46.8)	0.97 (0.78–1.2)	0.98 (0.79–1.22)
	Low birth weight (<2500 gram)
		Yes	26 (1.3)	4 (1.0)	0.71 (0.24–2.07)	0.69 (0.23–2.05)
		No	1987 (98.7)	406 (99.0)	reference	reference
	Preterm birth (gestational age at birth <37 weeks)
		Yes	68 (3.4)	10 (2.4)	0.66 (0.34–1.31)	0.65 (0.33–1.28)
		No	1934 (96.6)	399 (97.6)	reference	reference
	With symptom suspected of congenital infection
		Yes	38 (1.9)	10 (2.4)	1.41 (0.68–2.92)	1.46 (0.70–3.06)
		No	1975 (98.1)	400 (97.6)	reference	reference

*Odds ratio adjusted by mother’s age group.

Figure 1. Rubella seronegativity in total and each mothers’ age group in Nha Trang, Vietnam, 2009–2010 and 2017–2018

P-values: Rubella seronegativity in the total cohort and each mother’s age group were compared with those in a previous study,³ using the chi-squared test

Miyakawa M, Yoshino H, Yoshida LM, Vynnycky E, Motomura H, Tho LH, Thiem VD, Ariyoshi K, Anh DD, Moriuchi H. Seroprevalence of rubella in the cord blood of pregnant women and congenital rubella incidence in Nha Trang, Vietnam. Vaccine. 2014;32:1192–98. doi:10.1016/j.vaccine.2013.08.076.

 PubMed Web of Science ®Google Scholar