The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service is alerting veterinarians and others involved in the livestock industry in certain areas of the United States to be on the lookout for screwworm.

On February 27, 17 horses were imported into the United States from Argentina through APHIS’ animal quarantine center in Miami. Two of the horses were shipped to Georgia, five to California, one to Pennsylvania, one to Texas, and eight to Florida.

“We are asking veterinarians in private practice in those states where the horses were shipped to be on the lookout,” said Alfonso Torres, deputy administrator for APHIS’ veterinary services program, a part of USDA’s marketing and regulatory programs. Suspect cases should be reported to the USDA/APHIS area veterinarian in charge or to the state veterinarian.

On March 2, a private practitioner found one of the horses in West Palm Beach, Florida, to have screwworm larvae. The National Veterinary Services Laboratories in Ames, Iowa, confirmed that the larvae were screwworms on March 4. The horse and the premises were treated March 3; the horse received a second treatment March 6