Iowa Department of Agriculture and Land Stewardship Issues Guidance to Protect Animals from New World Screwworm

Iowa Department of Agriculture and Land Stewardship Issues Guidance to Protect Animals from New World Screwworm

DES MOINES, Iowa (June 9, 2026) - The Iowa Department of Agriculture and Land Stewardship (IDALS) issued the following guidance for livestock producers, pet owners, and veterinarians to help protect animals from the parasitic New World Screwworm (NWS) fly. The guidance comes after multiple cases of NWS have been detected in livestock in Texas and one infestation was confirmed in a canine in New Mexico.

All livestock caretakers and pet owners should routinely inspect animals for open wounds. If maggots are detected in an open wound of a warm-blooded animal, report it to IDALS immediately at 515-281-5305 or [email protected].

When caught early, animals and wounds can be treated, and animals can fully recover from NWS.

Guidance for importing livestock and companion animals into Iowa from an infested zone:

• Contact the State Animal Health Official in the state of origin for movement requirements.
• Visit IDALS' Animal Admission Health Requirements page or call 515-281-5547 to verify Iowa's import requirements.
• Isolate the imported animals from the rest of the herd for at least two weeks.
• Talk to your veterinarian if you have questions or concerns.

Guidance for importing livestock or companion animals into Iowa from areas not known to be infested:

• IDALS has not issued additional import requirements for non-infested zones at this time.
• Visit IDALS' Animal Admission Health Requirements page for current import requirements.

IDALS is closely monitoring the NWS situation and will determine if additional import requirements on warm-blooded animals moving to Iowa are necessary as the situation develops.

Best practices to protect against NWS:

• All animal caretakers should routinely inspect animals for open wounds. Open wounds should receive prompt veterinary care.
• Do not proactively treat livestock prophylactically for NWS at this time.
• Monitor animals for clinical signs of NWS, including irritated or depressed behavior, loss of appetite, headshaking, smell of decaying flesh, evidence of fly strike, presence of larvae in wounds, or self-isolating from other animals or people.
• If you find an open wound with maggots, you should call your veterinarian immediately.
• When traveling, companion animal owners should consult their veterinarians about their pet's external parasite prevention plan.

Livestock producers are encouraged to register for a Premises ID so they can be contacted in case of a NWS detection in their area.

Food Safety

The NWS does not pose a food safety risk. Properly prepared meat and poultry are safe to eat.

Public Health

The NWS primarily affects livestock but can also infest pets, wildlife and, in rare cases, people. It is considered a low risk to public health. If you have a human health concern, you should contact your primary care physician immediately. More information about the NWS risk to humans is available on the CDC website.

Additional Resources

• USDA APHIS New World Screwworm website
• Iowa Pork Industry Center NWS website (for pork producers)
• American Veterinary Medicine Association NWS website (for veterinarians)
• U.S. Food and Drug Administration NWS website (for veterinarians)
• IDALS NWS website