Oh Good, Screwworms Are Back

You say you want to know more about the horror bug that we eradicated only to discover it is making a comeback? You are in luck.

There’s always a crisis or what seems to be a crisis or people trying to make something a crisis. Sometimes the crisis is real, sometimes is a manipulation, sometimes it’s a genuine danger that could become a crisis. It is often hard to sort these things out and my coping strategy for dealing with some new crisis is to take that moment to learn about things in detail.

For example: have you heard that the Newworld Screwworm is threatening to infect our livestock supply? This sounds bad. Fortunately, I was able to research this and discover that it is very bad and there is a whole fascinating story about this horrific creature, how we eradicated it, and how Covid, open borders, and a stunning and frankly inexcusable amount of institutional incompetence has managed to take a solved problem and allow it become a fresh danger.

What Fresh Insect Hell Is This?

Unlike most flies that lay eggs in dead and rotting organic matter, the Newworld Screwworm lays eggs in the open wounds and mucus membranes of living animals. The maggots then eat the animal (or human!) alive. Its scientific name is cochleomyia hominivorax which literally means “man-eating snail”.

These little monsters have plagued livestock and humans in tropical and subtropical regions of the Americas for centuries. This includes the southern US, the Caribbean, and most of Central and South America. The devastation of these terrible creatures amounted to billions of dollars of yearly damage on top of the fact that they are extremely gross and cause massive human and animal suffering.

So why am I not already familiar with this thing? I’ve lived most of my life in a region of the US that is the historic breeding ground for the screwworm, why have I not heard anything about it?

That’s because, similar to the eradication of small pox, we used science and massive international institutional coordination to destroy this nasty little pest.

Human Ingenuity Gives The Middle Finger To Nature

In the 1930’s, Raymond Bushland and Edward Knipling were studying the screwworm in Texas where it was devastating livestock herds. These two scientists proposed and developing the “sterile insect technique” (SIT), which involves breeding the insects, sterilizing them with radiation, and releasing them into the wild. Because the female screwworm fly mates only once, if she mates with a sterile male fly any eggs she lays will not produce maggots.