New World screwworm genomics: implications for past, present, and future control strategies

The New World screwworm, Cochliomyia hominivorax, is a major pest of livestock, wildlife, and occasionally humans in the Americas. Larvae of C. hominivorax are obligate parasites that feed on the living tissues of warm-blooded animals, causing extensive damage, suffering, and death if untreated. C. hominivorax was eliminated from North and Central America through the first application of a genetic control method, the sterile insect technique (SIT), but re-invaded these areas from 2023 to present. The success of the renewed fight against C. hominivorax in North America, and beyond, will depend on the development and application of genetic technologies to augment and improve C. hominivorax control programs. Modern sequencing technologies and bioinformatics methods provide the tools necessary to advance research on comparative transcriptomics, functional genomics, population genetics, pesticide resistance, and the development of novel genetic-based biocontrol systems. The complete C. hominivorax genome is in its second iteration, providing an invaluable tool for developing next-generation control solutions for this species. Development of genetically engineered C. hominivorax sexing strains is ongoing and could greatly reduce SIT costs and improve production and field efficacy. Gene drives, which have incredible potential for population control, are in the early stages of development. Additionally, methods such as CRISPR-engineered sexing strains developed in other insect species could be transferred to C. hominivorax. Despite remaining gaps in our knowledge, the remarkable advances in New World screwworm genomics highlighted here provide a powerful foundation for translational research aimed at improving the management of this devastating pest.