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Volume 32, Number 10—October 2026
Research
Human Myiasis Resulting from Reemergence of Cochliomyia hominivorax Screwworm, Mexico, 2025–2026
Oscar Manuel Delgado-Cuellar, Clemente Mosso-González, Jorge Castañeda-Gómez, Farah Zamira Vera-Maloof, Karla Reyna Navarro-Fuentes, Edgar Sebastián Mejía-Navarro, and Héctor Armando Rincón-León
Table 1
Clinical and epidemiologic characteristics of confirmed cases of human myiasis resulting from reemergence of Cochliomyia hominivorax screwworm, Mexico, April 13, 2025–March 14, 2026*
| Characteristic | Male patients, n = 145 | Female patients, n = 57 | Total, n = 202 |
|---|---|---|---|
| Confirmed cases |
145 (100.0) |
57 (100.0) |
202 (100.0) |
| Age, y | |||
| Mean (SD) | 59.2 (19.0) | 65.9 (18.9) | 61.1 (19.2) |
| Range |
13–90 |
12–93 |
12–93 |
| Reported anatomic location | |||
| Lower limbs | 66 (45.5) | 45 (78.9) | 111 (55.0) |
| Neck | 27 (18.6) | 14 (24.6) | 41 (20.3) |
| Nose | 13 (9.0) | 9 (15.8) | 22 (10.9) |
| Mouth | 15 (10.3) | 6 (10.5) | 21 (10.4) |
| Eyes | 10 (6.9) | 6 (10.5) | 16 (7.9) |
| Head | 10 (6.9) | 6 (10.5) | 16 (7.9) |
| Upper limbs | 10 (6.9) | 4 (7.0) | 14 (6.9) |
| Trunk | 9 (6.2) | 3 (5.3) | 12 (5.9) |
| Ear | 2 (1.4) | 3 (5.3) | 5 (2.5) |
| Genitalia | 1 (0.7) | 1 (1.8) | 2 (1.0) |
| Abdominal cavity |
0 |
2 (3.5) |
2 (1.0) |
| No. concurrent conditions | |||
| 0 | 34 (23.4) | 13 (22.8) | 47 (23.3) |
| 1 | 80 (55.2) | 27 (47.4) | 107 (53.0) |
| 2 | 20 (13.8) | 12 (21.1) | 32 (15.8) |
| 3 | 8 (5.5) | 1 (1.8) | 9 (4.5) |
| >4 |
3 (2.1) |
4 (7.0) |
7 (3.5) |
| Concurrent condition | |||
| Diabetes mellitus | 29 (20.0) | 12 (21.1) | 41 (20.3) |
| Alcoholism | 27 (18.6) | 0 | 27 (13.4) |
| Hypertension | 12 (8.3) | 14 (24.6) | 26 (12.9) |
| Neoplasia | 20 (13.8) | 2 (3.5) | 22 (10.9) |
| Conditions associated with cutaneous ulcers | 10 (6.9) | 5 (8.8) | 15 (7.4) |
| Obesity | 5 (3.4) | 5 (8.8) | 10 (5.0) |
| Social abandonment/neglect | 6 (4.1) | 2 (3.5) | 8 (4.0) |
| Altered consciousness | 3 (2.1) | 4 (7.0) | 7 (3.5) |
| Recent surgery | 6 (4.1) | 1 (1.8) | 7 (3.5) |
| Venous insufficiency | 4 (2.8) | 2 (3.5) | 6 (3.0) |
| Other intoxicants | 4 (2.8) | 0 | 4 (2.0) |
| Psoriasis | 2 (1.4) | 1 (1.8) | 3 (1.5) |
| Sensory disorder | 1 (0.7) | 2 (3.5) | 3 (1.5) |
| Schizophrenia | 2 (1.4) | 1 (1.8) | 3 (1.5) |
*Values are no. (%) except as indicated. Percentages for male and female patients were calculated by using sex-specific denominators. Reported anatomic locations and concurrent conditions were not mutually exclusive categories; therefore, percentages may sum to >100%. The source reports did not provide a data dictionary for anatomic location terms or sufficient information to determine whether multiple listed locations represented separate infestations, contiguous extension of a single infestation, or different levels of anatomic description. Concurrent conditions reported in <2 cases are not shown individually. Data source: official monthly situation reports on human myiasis caused by Cochliomyia hominivorax in Mexico, Directorate General of Epidemiology, Ministry of Health (17).
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