Table 1.
Babesiosis Cases and Rates Among Elderly Medicare Beneficiaries, by Sex, Age, and Race, During 2006–2017
| Number of Babesiosis Cases (Babesiosis Rate per 100 000 Beneficiary-Yearsa) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sex and Age | All Years | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 |
| All Beneficiaries | |||||||||||||
| All Ages (65+)b,c | 19 469 (6) | 995 (4) | 853 (3) | 1225 (5) | 1500 (6) | 1317 (5) | 1374 (5) | 1226 (5) | 1889 (7) | 1823 (7) | 2521 (10) | 2303 (9) | 2443 (9) |
| 65–74 | 11 162 (7) | 537 (4) | 436 (4) | 678 (6) | 833 (7) | 739 (6) | 759 (6) | 720 (6) | 1093 (9) | 1063 (8) | 1537 (11) | 1353 (10) | 1414 (10) |
| 75–84 | 6370 (6) | 353 (3) | 319 (3) | 424 (4) | 512 (6) | 447 (5) | 478 (5) | 384 (4) | 621 (7) | 591 (7) | 756 (9) | 682 (8) | 803 (9) |
| ≥85 | 1937 (4) | 105 (2) | 98 (2) | 123 (3) | 155 (3) | 131 (3) | 137 (3) | 122 (3) | 175 (4) | 169 (4) | 228 (5) | 268 (6) | 226 (5) |
| Femalesd | |||||||||||||
| All Ages (65+)b,c | 10 117 (6) | 513 (3) | 444 (3) | 649 (4) | 815 (6) | 695 (5) | 718 (5) | 655 (4) | 959 (6) | 930 (6) | 1317 (9) | 1174 (8) | 1248 (8) |
| 65–74 | 5967 (7) | 284 (4) | 242 (4) | 365 (6) | 459 (7) | 410 (6) | 428 (7) | 405 (6) | 571 (8) | 549 (8) | 819 (11) | 708 (10) | 727 (10) |
| 75–84 | 3110 (5) | 173 (3) | 154 (3) | 215 (4) | 262 (5) | 210 (4) | 230 (4) | 180 (4) | 296 (6) | 310 (6) | 365 (8) | 322 (7) | 393 (8) |
| ≥85 | 1040 (3) | 56 (2) | 48 (2) | 69 (2) | 94 (3) | 75 (2) | 60 (2) | 70 (2) | 92 (3) | 71 (2) | 133 (5) | 144 (5) | 128 (5) |
| Malesd | |||||||||||||
| All Ages (65+)b,c | 9352 (7) | 482 (4) | 409 (4) | 576 (5) | 685 (6) | 622 (6) | 656 (6) | 571 (5) | 930 (8) | 893 (8) | 1204 (10) | 1129 (10) | 1195 (10) |
| 65–74 | 5195 (7) | 253 (4) | 194 (3) | 313 (6) | 374 (7) | 329 (6) | 331 (6) | 315 (5) | 522 (9) | 514 (8) | 718 (11) | 645 (10) | 687 (10) |
| 75–84 | 3260 (7) | 180 (4) | 165 (4) | 209 (5) | 250 (7) | 237 (6) | 248 (7) | 204 (5) | 325 (9) | 281 (7) | 391 (11) | 360 (10) | 410 (11) |
| ≥85 | 897 (5) | 49 (4) | 50 (4) | 54 (4) | 61 (4) | 56 (4) | 77 (5) | 52 (3) | 83 (5) | 98 (6) | 95 (6) | 124 (8) | 98 (7) |
| Racee | |||||||||||||
| Nonwhiteb | 973 (2) | 22 (1) | 29 (1) | 47 (1) | 62 (2) | 51 (2) | 48 (1) | 43 (1) | 72 (2) | 99 (3) | 141 (4) | 165 (4) | 194 (5) |
| Whiteb | 18 496 (7) | 973 (4) | 824 (4) | 1178 (5) | 1438 (6) | 1266 (6) | 1326 (6) | 1183 (5) | 1817 (8) | 1724 (8) | 2380 (11) | 2138 (9) | 2249 (10) |
aBabesiosis rates are rounded to the nearest whole number.
bThe trend of babesiosis occurrence rates during 2006–2017 is statistically significant according to the Cochran-Armitage test for trend, using a significance level of P < .05.
cFor “All Years”, significantly declining babesiosis rates (P < .05) with advancing age, by age categories, according to the Cochran-Armitage test for trend: overall and by sex, correspondingly.
dRate comparison of males vs females, resulted in relative risk (RR) = 1.24 and 95% confidence interval (CI) = 1.21–1.28.
eRate comparison of white vs nonwhite, resulted in RR = 2.98 and 95% CI = 2.79–3.18.