Table 1. Ratio of IgM+ confirmed cases to cases meeting the measles clinical case definition, by timing of specimen collection and vaccination status, the Republic of the Marshall Islands, 2003.
| Vaccination historya | Time of specimen collection (days after rash onset) |
||
|---|---|---|---|
| ≤ 3 | 4–28 | > 28 | |
| Ratio (%) | Ratio (%) | Ratio (%) | |
| Unknown | 3/10 (30) | 4/7 (57) | 5/11 (45) |
| No measles vaccination | 12/30 (40) | 11/15 (73) | 5/7 (71) |
| Measles vaccination (most recent dose ≥ 45 days before blood collection) | |||
| 1 dose | 5/7 (71) | 1/4 (25) | 0/1 (0) |
| 2 or more doses | 1/13 (8) | 4/9 (44) | 0/3 (0) |
| Measles vaccinationb (most recent dose < 45 days before blood collection) | |||
| 1 dose | 7/15 (47) | 9/14 (64) | 1/2 (50) |
| 2 or more doses | 0/2 (0) | 3/4 (75) | 0/0 (0) |
| Total samples | 77 (50) | 53 (34) | 24 (16) |
| Total IgM+ samples | 28 (36) | 32 (60) | 11 (46) |
a The clinical case definition was met by 169 individuals for whom serum was available; 154 of them are included in this table, and 15 were missing the dates needed to determine either the timing of blood collection or of vaccination. b IgM against the measles virus due to recent receipt of the measles vaccine cannot be differentiated from that due to recent measles infection.