● Covered by 1 source · 1 reportLow impact1 negative
Flesh-eating screwworms spread to Arizona, affecting pets and livestock
Key points
- NWS infestation spread to Arizona, a third US state.
- 74 animal cases identified in the US since June.
- Flies lay eggs in wounds, maggots consume living flesh.
- Mexico reported 806 human cases and 9 deaths.
Screwworms Reach Arizona
The New World Screwworm (NWS) infestation has expanded to Arizona, joining New Mexico and Texas as affected US states. This marks a significant spread of the parasite, which was previously eradicated from the country.
Since the re-invasion in June, 74 animal cases have been confirmed across the US. The screwworm larvae, or maggots, feed on living flesh after eggs are laid in animal wounds and moist orifices.
Biological Background and Re-emergence
NWS flies were eliminated from the US in the 1960s through a program involving the aerial release of sterile male flies. A biological barrier in the Darién Gap, between Panama and Colombia, maintained this eradication for years.
However, this barrier was breached in 2022, allowing the flies to re-enter the US via Central America. Their re-establishment poses a risk to animal populations.
Threat to Animals and Humans
While primarily a threat to the livestock industry, NWS can also impact wildlife and domestic pets. In rarer instances, humans can also be infested.
Mexico's Ministry of Health has reported 806 confirmed human screwworm infestations and 9 deaths since the flies re-emerged. The maggots bore into flesh, causing severe and potentially fatal wounds.
✨ This summary was generated by AI from the outlets' reporting listed below. It is not independently verified and may contain errors — check the original sources. How BrevFeed works →
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Reporting from
New World Screwworm (NWS) infestations have spread to Arizona, making it the third US state affected, alongside New Mexico and Texas. Since June, 74 animal cases have been identified in the US, with the maggots posing a threat to livestock, wildlife, pets, and, in rare instances, humans.