Table 2.

Unadjusted vaccine effectiveness by MuCV dosage and vaccination interval, Lu’an, China, 2016–2017.

Vaccination characteristics	Cases	Population at Risk	AR (%)	RR (95% CI)	VE (%, 95% CI)
Doses of MuCV
Not vaccinated	21	103	20.4	Ref.	Ref.
One dose	60	722	8.3	0.41(0.26–0.64)	59(36–74)
Two doses	8	151	5.3	0.26(0.11–0.51)	76(49–89)
Three doses	0	15	0.0	0	100
Years since one dose MuCV vaccination
Not vaccinated	21	103	20.4	Ref.	Ref.
< 5	3	80	3.8	0.18(0.06–0.60)	82(40–94)
5-	44	533	8.3	0.40(0.25–0.65)	60(35–75)
10-	13	109	11.9	0.59(0.31–1.11)	41(−11–69)
Years since the second dose of MuCV vaccination
Not vaccinated	21	103	20.4	Ref.	Ref.
< 5	1	48	2.1	0.10(0.01–0.74)	90(26–99)
5-	5	90	5.6	0.27(0.11–0.69)	73(31–89)
10-	2	13	15.4	0.75(0.20–2.86)	25(−186–80)