Effective Jan. 21, 2025, the Animal and Plant Health Inspection Service (APHIS) will again permit the importation of equids from Mexico with additional mitigations to guard against introduction of New World screwworm (NWS). APHIS temporarily suspended livestock imports from Mexico after that country detected NWS on Nov. 22, 2024. New World screwworm (Cochliomyia hominivorax) is a devastating pest that can cause serious, often deadly damage to the affected animal. 

The Animal and Plant Health Inspection Service and Mexico’s National Service for Health, Safety, and Food Quality (SENASICA) have now developed an import protocol that details a stepwise NWS preclearance inspection and treatment plan based on APHIS regulations for importation of equids from NWS-affected regions. Equids will also undergo examinations for screwworm during the required import quarantine. The protocol and associated health certification documents are available on the APHIS website.

In summary, equids must be inspected by an approved veterinarian for evidence of NWS infestation and treated with ivermectin or an equivalent APHIS-approved product within three to five days prior to entry into import quarantine. Oral ivermectin paste formulated for horses and administered per the manufacturer’s label may be used instead of injectable ivermectin. 

In addition, the equids must be inspected under direct supervision of a SENASICA veterinarian within 24 hours prior to entry into import quarantine and any visible wounds treated at that time. Certification of both inspections must be presented at the time of importation. The Animal and Plant Health Inspection Service will examine the equids for NWS on the first and last days of the seven-day import quarantine. Animals with evidence of NWS infestation at any point in the process are not eligible to import until they are treated, wounds are healed, and they are found free of NWS.