TABLE 2.

Prevalence of IgG and IgM to rMXV in 20 normal sera, as determined by an ELISA

Age range (yr)	No. of sera positive for:
	IgGa	IgMb
1–4	12	2
5–17	9	0
18–29	18	0
30–59	18	0

^aTiter of ≥1:100. 

^bTiter of ≥1:25.