Yucatán Confirms 48 Screwworm Myiasis Cases, 57% of Peninsula Total

Mérida, Yucatán — Health officials have confirmed another human case of screwworm myiasis in Yucatán, bringing the state to 48 cases so far this year, according to federal health sector data.

The report did not specify the patient’s municipality of residence or their current condition.

Yucatán accounts for 57 percent of the 84 cases recorded across the three states of the Yucatán Peninsula in 2026. Quintana Roo has reported 25 cases and Campeche 11.

In an Oct. 16 alert, the Pan American Health Organization (PAHO) reported that as of epidemiological week 37, Yucatán had accumulated 39 cases, Quintana Roo 23 and Campeche nine, showing that new infections have continued to be detected since then.

One death recorded in March

Yucatán’s tally includes one death. On March 20, the state Health Department announced the death of a patient diagnosed with myiasis who also had complex pre-existing conditions. The department said the patient received specialized care and that epidemiological follow-up of the case was launched.

State health authorities said epidemiological surveillance remains in place.

How screwworm myiasis is acquired

Myiasis occurs when the Cochliomyia hominivorax fly, known as the screwworm, lays its eggs in a wound or exposed mucous membrane. The larvae feed on living tissue and can cause pain, inflammation and progressive damage to the affected area. PAHO notes that the infestation is not transmitted from person to person.

People with untreated wounds, chronic ulcers or recent surgical wounds face the greatest risk.

Warning signs that require medical attention

The National Center for Disease Prevention and Control (CENAPRECE) recommends keeping wounds clean and covered and checking them until they heal. It advises going to a medical facility immediately if there is persistent pain, bad odor, discharge, delayed healing or the presence of larvae. People who have trouble inspecting or dressing their own wounds should ask family members or caregivers for help.