Volume 15, Number 11—November 2009
Letter
Low Immunity to Measles and Rubella among Female Guest Workers, Northern Mariana Islands
Table
Proportion of guest workers immune to measles and rubella by ethnicity and age group, Northern Mariana Islands, September–October 2006*
Age group, y | Proportion immune |
||||||
---|---|---|---|---|---|---|---|
Guest workers from China |
Guest workers from other countries† |
||||||
Total no. tested | No. (%) measles, 95% CI | No. (%) rubella, 95% CI | Total no. tested | No. (%) measles, 95% CI | No. (%) rubella, 95% CI | ||
15–19 | 18 | 17 (94.4), 72.7–99.9 | 14 (77.8), 52.4–93.6 | 0 | – | – | |
20–24 | 56 | 41 (73.2),59.7–84.2‡ | 49 (87.5), 75.9–94.8 | 1 | 1 (100), 2.5–100§ | 1 (100), 2.5–100§ | |
25–29 | 40 | 25 (62.5), 45.8–77.3‡ | 36 (90.0), 76.3–97.2 | 10 | 10 (100), 69.2–100§ | 10 (100), 69.2–100§ | |
30–34 | 18 | 13 (72.2), 46.5–90.3‡ | 15 (83.3), 58.6–96.4 | 9 | 9 (100), 66.4–100§ | 8 (88.9), 51.8–99.7 | |
35–39 | 17 | 14 (82.4), 56.6–96.2 | 13 (76.5), 50.1–93.2 | 16 | 16 (100), 79.4–100§ | 15 (93.8), 69.8–99.8 | |
40–44 | 2 | 2 (100), 15.8–100§ | 2 (100), 15.8–100§ | 14 | 14 (100), 76.8–100§ | 11 (78.6), 49.2–95.3 | |
>45 |
2 |
2 (100), 15.8–100§ |
1 (50.0), 1.3– 98.7 |
6 |
6 (100), 54.1–100§ |
5 (83.3), 35.9–99.6 |
|
Total | 153¶ | 114 (74.5), 66.8–81.2# | 130 (85.1), 78.3–90.2 | 56 | 56 (100), 93.6–100§ | 50 (89.3), 78.1–96.0 |
*CI, confidence interval.
†Philippines (n = 48), Japan (n = 6), South Korea (n = 1), Thailand (n = 1).
‡Significant difference in measles immunity of Chinese workers 20–34 years of age compared with that of Chinese workers of other age groups; p = 0.01.
§1-sided confidence interval.
¶The age of 1 guest worker was not provided by the referring laboratory.
#Significant difference in measles immunity between workers from China and other countries; p<0.001.