New World Screwworm

The New World screwworm is a parasitic fly that lays eggs in fresh wounds or openings of warm-blooded animals. Once hatched, the larvae feed on living tissue, causing severe damage, secondary infections and, if untreated, death. This invasive pest poses a significant threat to livestock, wildlife, pets and, in rare cases, people, making early detection and rapid response essential.

Active wildlife monitoring plays a critical role in limiting the spread of New World screwworm to livestock, pets and surrounding ecosystems. Landowners, hunters and natural resource professionals can help protect native species by regularly observing animals for wounds or unusual behavior and reporting suspected infestations.

If you suspect New World screwworm in livestock or other animals, immediate action is critical to protect animal health and prevent further spread. Inspect animals for wounds or signs of larvae, report suspected cases to animal health officials and collect information or samples if directed by a veterinarian.

Proactive livestock management is essential to reduce the risk of New World screwworm infestations. Producers should prioritize wound prevention, timely treatment and increased monitoring during periods of high fly activity. Scheduling procedures that create wounds for cooler weather months can also protect herd health.

While New World screwworm primarily affects livestock and wildlife, rare cases of human infestation (myiasis) can occur when flies lay eggs in untreated wounds. Maintaining proper wound care and seeking medical attention when symptoms appear are key to reducing the risk of painful tissue damage.

Dogs, cats and other companion animals are also at risk for New World screwworm infestation, particularly if they have untreated wounds or spend time outdoors. Pet owners should routinely check animals for injuries, maintain proper wound care and consult a veterinarian if signs of infestation appear.

Swine producers can reduce the risk of New World screwworm by closely monitoring animals for wounds, especially during routine production activities that create breaks in the skin like tagging or processing.

Los conocimientos necesarios para monitorear, detectar y notificar signos de infestación por gusano barrenador en animales silvestres.

Aunque el ganado y la fauna silvestre representan la mayoría de los casos de GBNM en una región determinada, los perros y los gatos también corren riesgo. Observe a sus mascotas en busca de signos de infestación.

The northern migration from central America of the New World screwworm (NWS), Cochliomyia hominivorax, poses a renewed threat to Texas and United States livestock producers.