US Reports First Human Case Of Flesh-eating Screwworm

The United States has reported its first human case of the flesh-eating screwworm, a parasitic fly whose larvae feed on living tissue. The case was confirmed in a Maryland resident who recently returned from El Salvador, where an outbreak of the screwworm is ongoing.

The patient began showing symptoms shortly after returning and was diagnosed on August 4, 2025. The Centers for Disease Control and Prevention (CDC) emphasized the importance of prompt treatment to prevent serious and potentially fatal infections.

The US Department of Health and Human Services (HHS) confirmed the case on August 24, 2025, and is closely monitoring the situation to prevent the spread of the screwworm. The USDA is taking measures to limit the spread of the pest, including constructing a sterile fly production facility in Texas.

This first human case underscores the need for vigilance and early detection to protect public health and agriculture.