The Resurgance of a Menace.. ** Squirm Alert **

[Silas_Sancona]

****  Fair warning   ..For those a bit squeem-ish when it comes to gross things,  you might want to look away..   ****

A few years back, i'd mentioned something ..somewhere.. regarding an insect " pest " that  legitimately qualifies as a threat.. Not necessarily to plants,  but  to ..anything else, inc. humans.. 


While flies themselves are pretty gross creatures, the New World Screw worm,  Cochliomyia homnivorax  ups the " Gross " factor  ..just a bit..  The Latin name literally translates to " Man Eater "  ..and yes, this Bug- eyed, Obligate Parasite can kill a man ( ..or woman ) and was once one of the greatest threats to livestock in the US  " back in the day "  ...up until it was eradicated from the US in the early 80s.

That campaign continued thru the 90s / earlier 2Ks until this insect was beaten back to -roughly- the Darien Gap in Panama. Beyond that, in South America, and some islands in the Caribbean where it hangs on,  the efforts to fully take out this insect has been challenging due to terrain, costs, and / or political will.

It was gone here in the states until it quietly reappeared in the FL. Keys sometime in 2016 where the outbreak seen there killed numerous Key Deer, and was detected in a stray Dog in Homestead just north of the designated quarantine zone there before the control measures used to knock down this insect worked as planned.

Fast forward to last summer, and while doing my yearly " check in " on efforts to control / any new, general research on this insect,  there were reports coming out of both Panama and Costa Rica of new outbreaks being seen in some areas of both countries.

Tack on another year and it appears the threat posed by this insect is quickly spreading across all of Central America, with a detection noted in Chiapas in the last couple weeks.. This is occurring despite re-invigorated and stepped up efforts to get the more severe outbreaks in Panama and Costa Rica under control again..

When i'd read the last reports of it being detected in Guatemala, i had a feeling it wouldn't be long until it reached southern Mexico.. That has happened..  Question now is ..how far north will it progress? ..and can the control efforts currently underway stop the advance - before- outbreaks are detected much closer to the US?

Before full eradication, when it roamed the US, outbreaks were seen as far west as central California, As far north as the Central Plains and Southeastern states, north of FL. It was also sporadically detected in the upper Midwest during years when conditions were ideal.

Another question regarding this current resurgence involves whether or not the female flies of this species have gained some sort of new ability to " sus out " the sterilized males released and now avoid them..  That would destroy the current means of effective control of course.  Maybe a vaguely rumoured strain of the species that was rumoured to possess some resistance to radiation, that is spreading into new areas is responsible?? ..Time will tell...


Regardless, putting this out there as a " Keep your eyes -and ears- on this situation over the coming months " kind of  advise, rather than a " The sky is about to fall " alarm.  Understand the difference..



Highly doubt this fly will return to the US  -in any great numbers at least- but,  We'll have to see since  -so far- the extra aggressive response to this current situation isn't seeming to have much effect.. That said, ..as was the case in the past when the battle began, full, regional control can take up to several years..

In that time, reports of sporadic, localized outbreaks aren't completely out of the question further north in Mexico, and / or possibly in FL. again, and perhaps the border regions of Texas / other states, depending on what weather events occur..  It is thought that the outbreak seen in FL. was a result of flies being blown north from Cuba by a Hurricane.  Should such occur, it wouldn't be out of the question that the occasional sterilized fly turns up in someone's yard.

Won't post it here but there is a really good observation on iNaturaliust that details the trademark markings of adult NWS flies, ...as compared to the ..roughly, 4 or 5 other species of similar looking fly species that are common in the US,  None of which cause the same issues as NWS.

One significant step has apparently been made in that the US has now suspended all imports of Cattle from Mexico. I don't doubt restrictions on the importation / movement of other livestock may occur if outbreaks expand north beyond far southern Mexico over the coming months.

Something to monitor casually,  but closely.. 


Related articles...  Will add more  when / if  need be..

*** As stated at the top,  .If gross things make ya' squirm,   turn away ***

Scientists built a great wall to keep out the ‘man devourer’ – but now it’s fighting back

https://www.cdc.gov/coca/hcp/trainings/resurgence-new-world-screwworm.html

https://u.osu.edu/beef/2024/11/27/cattle-imports-from-mexico-restricted-after-new-world-screwworm-detection/

https://publications.aap.org/aapnews/news/30599/Twice-eradicated-parasite-threatens-northward?autologincheck=redirected

[Looking Glass]

Screw worms and bot fly larva.  Two things I don’t need around the yard.  I go outside and work for hours at a time til sun set, getting bit by tombs of mosquitos all day long.  I don’t wear bug spray or react to the bites anymore.  It just leaves a flat tiny red dot with no itching.   Horse flies and deer flies are annoying, but a can’t imagine having to worry about this.  Tropical worms please stay in the tropics.  

 

I used to remove bot fly larva from our animals growing up on a mini farm.  It was rare, bit memorable.   You’d occasionally see sick, small mammals, like deer mice, with them hunting or fishing.  I can’t imagine screw worms.   That’s a whole other level with a lot of impact on farming.