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Volume 31, Number 9—September 2025
Research
Differences in Lyme Disease Diagnosis among Medicaid and Medicare Beneficiaries, United States, 2016–2021
, Sarah J. Willis, Christopher G. Prener, Stephanie A. Duench, Holly Yu, Luis Jodar, Jennifer C. Moïsi, and James H. Stark
Table 1
Number of cases and incidence in a study of differences in Lyme disease diagnosis among Medicaid and Medicare beneficiaries, United States, 2016–2021*
| Group | Total no. (%) cases† | Localized Lyme disease |
Disseminated Lyme disease |
|||||
|---|---|---|---|---|---|---|---|---|
| No. cases | Person-years | Incidence‡ | No. cases | Person-years | Incidence‡ | |||
| Medicaid, age <18 y | 33,776 | 27,165 | 37,110,817 | 73.3 | 5,798 | 27,058,337 | 15.7 | |
| White | 29,405 (87.1) | 24,093 | 17,461,207 | 138.1 | 4,576 | 17,412,994 | 26.3 | |
| Black, African American | 1,244 (3.7) | 744 | 9,611,964 | 7.8 | 483 | 9,611,379 | 5.0 | |
| Asian, Pacific Islander | 741 (2.2) | 551 | 2,783,663 | 19.8 | 181 | 2,782,940 | 6.5 | |
| Hispanic | 2,063 (6.1) | 1,526 | 6,833,641 | 22.4 | 495 | 6,831,111 | 7.3 | |
| Native American | 208 (0.6) | 159 | 268,217 | 59.3 | 44 | 267,950 | 16.4 | |
| Other |
115 (0.3) |
92 |
152,126 |
60.5 |
19 |
151,963 |
12.5 |
|
| Medicaid, age >19 y | 30,935 | 23,663 | 25,536,958 | 92.7 | 5,380 | 25,496,013 | 21.1 | |
| White | 26,298 (85.0) | 20,456 | 13,156,621 | 155.6 | 4,214 | 13,120,278 | 32.1 | |
| Black, African American | 1,461 (4.7) | 978 | 6,188,543 | 15.8 | 408 | 6,187,289 | 6.6 | |
| Asian, Pacific Islander | 1,082 (3.5) | 813 | 2,745,246 | 29.6 | 212 | 2,743,918 | 7.7 | |
| Hispanic | 1,867 (6.0) | 1,253 | 3,235,335 | 38.8 | 500 | 3,233,589 | 15.5 | |
| Native American | 191 (0.6) | 133 | 168,295 | 79.1 | 40 | 168,080 | 23.8 | |
| Other |
36 (0.1) |
– |
– |
– |
– |
– |
– |
|
| Medicare, age <65 y | 12,911 | 8,204 | 6,933,720 | 118.4 | 3,293 | 6,923,326 | 47.6 | |
| White | 11,845 (91.7) | 7,581 | 5,149,098 | 147.3 | 2,930 | 5,139,283 | 57.1 | |
| Black, African American | 513 (4.0) | 284 | 1,267,371 | 22.4 | 205 | 1,267,135 | 16.2 | |
| Asian, Pacific Islander | 72 (0.6) | 50 | 105,505 | 47.4 | 16 | 105,440 | 15.2 | |
| Hispanic | 293 (2.3) | 181 | 284,434 | 63.7 | 84 | 284,264 | 29.6 | |
| Native American | 53 (0.4) | 32 | 32,348 | 99.0 | 14 | 32,306 | 43.4 | |
| Other |
135 (1.0) |
76 |
94,964 |
80.1 |
44 |
94,897 |
46.4 |
|
| Medicare, age >65 y | 90,913 | 65,298 | 31,199,802 | 209.4 | 16,938 | 31,087,605 | 54.5 | |
| White | 87,831 (96.6) | 63,252 | 27,353,152 | 231.4 | 16,201 | 27,243,943 | 59.5 | |
| Black, African American | 1,172 (1.3) | 753 | 2,299,786 | 32.8 | 324 | 2,298,791 | 14.1 | |
| Asian, Pacific Islander | 591 (0.7) | 410 | 649,660 | 63.2 | 141 | 649,082 | 21.7 | |
| Hispanic | 283 (0.3) | 183 | 357,614 | 51.2 | 76 | 357,380 | 21.3 | |
| Native American | 64 (0.1) | 45 | 30,197 | 149.1 | 14 | 30,127 | 46.5 | |
| Other | 872 (1.1) | 655 | 509,397 | 128.7 | 182 | 508,283 | 35.8 | |
*–, sample size too small to calculate rate. †Total cases include all cases of Lyme disease identified during the study period. For incidence rate calculations, we included only the first case during the study period for beneficiaries with subsequent Lyme disease diagnoses. ‡Incidence rate was calculated across the entire study period among all persons who had <183 days of continuous enrollment in Medicaid or Medicare and resided in a high incidence state as follows: incidence = [(number beneficiaries with Lyme disease algorithm-defined Lyme disease)/(observed person-time at risk for Lyme disease)] × 100,000 person-years.