Official Pest Report

Official Pest Reports are provided by National Plant Protection Organizations within the NAPPO region. These Pest Reports are intended to comply with the International Plant Protection Convention's Standard on Pest Reporting, endorsed by the Interim Commission on Phytosanitary Measures in March 2002.

Ceratitis capitata (Mediterranean Fruit Fly): APHIS Removes Quarantine in Alameda and Santa Clara Counties, California (OPR-41)

Country: United States

Title:

Ceratitis capitata (Mediterranean Fruit Fly): APHIS Removes Quarantine in Alameda and Santa Clara Counties, California (OPR-41)

Contact:
Catherine Marzolf, National Policy Manager, 386-666-9932 or catherine.a.marzolf@usda.gov

Report:

On July 31, 2025, the USDA’s Animal and Plant Health Inspection Service (APHIS) and the California Department of Food and Agriculture (CDFA) removed the Mediterranean fruit fly (Ceratitis capitata; Medfly) quarantine in Alameda and Santa Clara Counties, designated the Fremont quarantine. This action released 213 square miles including 49 acres of commercial agriculture from quarantine. Release from quarantine occurred after three generations elapsed since the date of the last detection, based on a degree-day model.

APHIS and CDFA established the Fremont Medfly quarantine on September 6, 2024, and expanded it on September 11, October 17, October 23, October 30, November 8, December 5, and December 12, following the detections of additional Medflies. APHIS restricted the interstate movement of regulated articles from this area to prevent the spread of Medfly to non-infested areas of the United States. APHIS worked cooperatively with CDFA and the Agricultural Commissioners of Alameda and Santa Clara Counties, to eradicate this transient Medfly population through various control actions per program protocols.

The removal of this quarantine area is reflected on the APHIS Exotic Fruit Flies website, which contains a description of all current Federal fruit fly quarantine areas. APHIS will publish a notice of this change in the Federal Register.

Under IPPC standards, Ceratitis capitata is a transient pest under eradication that is present only in one area in California. This species is not widely distributed and is under official control in the United States.

Posted Date: Nov. 25, 2025, 11:50 a.m.