Florida has been hit again, not by another hurricane this time, but by a screwworm outbreak. Fortunately, no human case has been reported yet.
Screwworms are carnivorous flies which have killed many Key deer specimens since September. A local infestation has been confirmed on September 30th by the United States Department of Agriculture, whereas Adam Putnam, state Commissioner of Agriculture, issued an official state of emergency in Monroe County.
These flesh-eating insects lay their eggs in an animal’s open wound. When a specimen gets infected, it leaves the herd and dies within two weeks if it’s not treated. Based on the latest reports, no livestock cases occurred, and the infestation was isolated in No Name Keys and Big Pine Keys.
Wildlife officials and authorities will double their efforts to prevent the worms from spreading any further. What puzzles experts is that they don’t know the origin of the screwworm yet. Some theories point towards the possibility that the carnivorous worm was brought by animals which are not endemic to the area.
It is the first time in more than three decades when Florida is hit by an infestation and the first time in fifty years when the screwworm appears in Florida. Scientifically called Cochliomyia hominivorax, this worm’s eggs hatch as larvae and feast on the host’s live tissue. After around one week, the worms leave the host, get under the ground and emerge after a few days as flies.
This species is very dangerous because a female screwworm can lay thousands of eggs during its lifespan. The infected deer suffer a slow and painful death, so they are shot on sight when authorities come across them.
Although these flies usually aim for fawns, adult specimens are sometimes infected as well. According to Putnam, due to the rutting period, many bucks are fighting each other over females, so they suffer many open wounds during their clashes.
This is how screwworms find their way in and lay their eggs inside the open wounds. This high mortality percentage is quite concerning, so experts believe that a viable solution is to introduce sterile male flies.
This way, female flies will still breed but will no longer lay any eggs. This method was first used back in 1950 when Florida faced the last screwworm outbreak.