Rare Human Screwworm Cases Confirmed in Oaxaca, Mexico
The Health Services of Oaxaca (SSO) has confirmed two cases of screwworm infection in humans, detected during epidemiological week 46. The cases, identified through larval analysis of patient wounds, represent a rare occurrence of the disease affecting people, as it primarily impacts livestock.
The SSO reported that the first case involved a 48-year-old man with a history of diabetes mellitus, residing in Sanitary Jurisdiction 3 Tuxtepec. According to the agency, the infection manifested as an ulcer on a pelvic limb. “The disease occurred in an ulcer of a pelvic limb and, after receiving timely treatment, he was discharged without complications,” a senior official stated.
The second confirmed case is a 73-year-old man from Sanitary Jurisdiction 1 Valles Centrales, who received treatment at the “Dr. Aurelio Valdivieso” General Hospital, operated by IMSS-Wellbeing. The presence of larvae was identified during a medical check-up related to healing complications following a graft procedure. “During the medical check-up due to graft healing problems, the presence of larvae was identified; after the immediate intervention, the patient no longer has the condition,” the SSO confirmed.
The agency emphasized that while screwworm predominantly affects animals, the risk to the general population remains low with proper wound care. The Cochliomyia hominivorax fly, responsible for transmitting the infection, deposits its larvae in open wounds such as sores, ulcers, cuts, scrapes, or recent surgical sites.
In response to these cases, the SSO has activated surveillance and containment protocols in coordination with the National Service of Health, Safety and Agri-Food Quality (Senasica) and the Secretariat of Agri-Food Promotion and Rural Development (Sefader). These measures include reinforcing health education initiatives within communities to promote early detection of potential cases.
The SSO strongly recommends that individuals practice strict hygiene when dealing with any open wound. Individuals experiencing symptoms such as a sensation of movement within a wound, burning, a foul odor, or visible larvae should seek immediate medical attention at the nearest healthcare facility.
