Table 2.

MuCV effectiveness by time since vaccination among students receiving 1 MuCV dose prior to a mumps outbreak in Anhui province, China, 2014–2015.

Years since vaccination	Cases	Exposed persons	AR (％)	RR (95%CI)	VE (％,95％CI)
Un-vaccinated	93	530	17.5	Ref	Ref
<3 years	3	46	6.5	0.37(0.12,1.13)	63(0,88)
3-5 years	30	339	8.8	0.50(0.34,0.74)	50(26,66)
>5 years	90	780	11.5	0.66(0.50,0.86)	34(14,50)