TABLE 1

Characteristics of suspected measles cases included in each ROC analysis with epidemiologic context described for RICs and noncases

Type case and ROC analysis (n)No. (%) with PRN concn of ≥40,000aDaysb (median)No. (%) IgM positivecNo. (%) with known contact with caseNo. (%) associated with outbreak and/or travelNo. (%) of known sources of additional casesNo. (%) with MMR vaccinationd
RICs (57)
    Sample 1 (57)18 (31)0–11 (2)29 (51)35 (61)56 (98)5 (9)33 (58)
    Sample 2 (31)28 (90)3–30 (6)21 (68)
Noncases (20)
    Sample 1 (20)1 (5)0–11 (2)9 (45)2 (10)5 (25)0 (0)17 (85)
    Sample 2 (20)1 (5)5–42 (9)8 (40)
  • a Concentration, in mIU/ml, of measles neutralizing antibody determined by PRN assay.

  • b Interval, in days after rash onset, of serum collection.

  • c Positive by CDC measles IgM capture assay.

  • d Receipt of one or more doses of MMR vaccine according to case investigation.