Table 2.
Percentage of children aged 12 months through 6 years who received an invalid dose of MMR, varicella, or MMRV due to live vaccine conflict following a prior live vaccine at six IIS Sentinel Sites* from July 1, 2016 – December 31, 2017†.
| Live vaccine of interest⁋ | Prior live vaccine causing live vaccine of interest to be invalid | Live vaccine conflict interval§, days | Number of children who received ≥ 1 dose of live vaccine of interest, n | Number of children who received ≥ 1 invalid dose of live vaccine of interest, n (%) | Median number of days between prior live vaccine and invalid dose (IQR††) | Revaccination cost∞ for invalid doses** of live vaccine of interest, $ |
|---|---|---|---|---|---|---|
| Varicella | 280,351 | 639 (0.2) | 120,131 | |||
| MMR | 1–27 | 544 (85.1) | 12 (14) | |||
| Varicella | 1–23 | 34 (5.3) | 14 (9) | |||
| MMRV | 1–27 | 11 (1.7) | 13 (15) | |||
| §§Multiple | 50 (7.8) | NA | ||||
| MMR | 289,128 | 391 (0.1) | 49,499 | |||
| MMR | 1–23 | 8 (2.0) | 14 (9) | |||
| Varicella | 1–27 | 294 (75.2) | 13 (15) | |||
| MMRV | 1–27 | 11 (2.8) | 14 (16) | |||
| §§Multiple | 77 (19.7) | NA | ||||
| MMRV | 382,380 | 48 (0.01) | 11,934 | |||
| MMR | 1–27 | 15 (31.3) | 19 (17) | |||
| Varicella | 1–27 | 6 (12.5) | 19 (16) | |||
| MMRV | 1–27 | 12 (25.0) | 19 (9.5) | |||
| §§Multiple | 14 (29.2) | NA | ||||
| TOTAL | 704,591 | 1,001 (0.1) | 14 (13) | 181,565 |
Michigan, Minnesota, North Dakota, Wisconsin, New York City, and 6 contiguous Oregon counties
LAIV was not recommended for use from 2016–17
Number of days referred to as the ‘live vaccine conflict interval’ which begins the day after a dose of the prior live vaccine identified in CDSi version 3.7. A live vaccine administered during the conflict period specific to the prior live vaccine indicates an invalid dose.
Interquartile range of median
Trade name for live vaccines: Varicella (Varivax [Merck and Co., Inc., Whitehouse Station, NJ]); MMR (M-M-R-II [Merck and Co., Inc., Whitehouse Station, NJ]); MMRV (Proquad).
Revaccination cost calculated as c = n (p + a + w + t) (Rodgers, et al. 2018), where n is the number of invalid doses, p is the price per vaccine dose,a is administrative cost per vaccine (set to $9.11 public clinic and $32.50 private practice for 2016–17), w is cost for patient or caregiver time (set to $19.14 per hour for 2016–17) for 2 hours for time take off work, and t is transit cost to provider’s office (set to $24.68 for 2016–17).
Number of total invalid doses: varicella = 640, MMR = 398, MMRV = 50.
More than one live vaccine of interest was administered during the conflict interval.
NA Median not available due to more than one conflict interval for multiple live vaccines