Waco Receives 32,000 NexGard Doses Worth $600K to Combat Screwworm

For the biopharma sector, the emergency deployment of Boehringer-Ingelheim's NexGard against screwworm is a compelling case of label expansion by necessity. The donation not only addresses an immediate animal health crisis but also generates invaluable real-world evidence on afoxolaner's efficacy against a historically devastating parasite, potentially reshaping the competitive landscape for veterinary antiparasitics and informing regulatory discussions on prophylactic indications.

In a significant public-private partnership, Waco, Texas, has accepted a donation of 32,000 doses of NexGard (afoxolaner) valued at nearly $600,000 to combat the emerging threat of New World Screwworm (Cochliomyia hominivorax). The donation, orchestrated by the Bissell Pet Foundation in collaboration with pharmaceutical manufacturer Boehringer-Ingelheim, marks a proactive intervention aimed at protecting local pets and livestock from a destructive parasitic fly that has reemerged in the southern United States. While McLennan County has yet to report a single confirmed case, the city's decision reflects growing anxiety over 45 total screwworm infections documented nationwide since early June 2026, with Texas managing five active cases, including a recent detection in a Terrell County sheep.

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In a significant public-private partnership, Waco, Texas, has accepted a donation of 32,000 doses of NexGard (afoxolaner) valued at nearly $600,000 to combat the emerging threat of New World Screwworm (Cochliomyia hominivorax).

The New World Screwworm is a parasitic insect whose larvae feed on the living tissue of warm-blooded animals. Female flies deposit eggs in open wounds—from minor tick bites to severe injuries—and the hatching larvae burrow into flesh, causing extensive tissue damage, secondary infections, and often death if untreated. The pest was declared eradicated from the United States in 1966 through the sterile insect technique, but periodic reintroductions from endemic regions in Central and South America continue to pose biosecurity risks. The current cluster of cases, though modest, has prompted aggressive local responses given the screwworm's rapid reproductive cycle and its capacity to infest domestic dogs, cats, and livestock alike.

Boehringer-Ingelheim's NexGard is an isoxazoline-class parasiticide originally approved for flea and tick control in dogs. Its active ingredient, afoxolaner, acts by inhibiting ligand-gated chloride channels in arthropod nervous systems, a mode of action that likely confers efficacy against screwworm larvae as well. While the U.S. Food and Drug Administration has not specifically labeled NexGard for screwworm prevention, the donation aligns with a long-standing veterinary practice of extrapolating approved indications based on pharmacologic similarity. The emergency deployment of NexGard in Waco thus not only addresses an immediate animal health crisis but also generates critical real-world data on afoxolaner's effectiveness against Cochliomyia hominivorax, potentially supporting future label expansions or new product development in the Boehringer-Ingelheim animal health portfolio.

The logistics of the donation involve a coordinated distribution network: the Pet Circle Animal Center, a local shelter, will lead the effort together with the Animal Birth Control Clinic. Priority recipients include vulnerable pets and low-income residents whose animals may lack consistent veterinary care. Shelter intake protocols are being upgraded to place all incoming animals on NexGard prophylactically, coupled with rigorous physical inspections for open wounds. Staff will screen for neurological conditions like seizures before administration, reflecting a cautious approach given the class-wide warning for isoxazolines. This model of distribution—leveraging existing animal welfare infrastructure for pharmaceutical deployment—could serve as a blueprint for future zoonotic or vector-borne disease outbreaks in resource-limited settings.