Entomologist (bug scientist) Dr Justin Schmidt from Arizona, USA, was curious to discover more about the effects of insect stings. So in 1983 he developed the Schmidt Sting Pain Index to measure the painfulness of different stingers. The index runs from “1” (mild) to “4” (severe).

To give a sense of what those numbers mean, the sting of the average honey bee or wasp is rated at a "2". However, the Schmidt Sting Pain Index isn't just about a 1–4 scale. In addition to a numerical rating, Dr Schmidt also accompanies many of his sting assessments with a short qualitative summary to describe the type of pain and how long it lasts. Arguably, it's these descriptions that really capture the essence of how (and how much) a sting really hurts!

GWR: Why did you develop the index?

Dr Justin Schmidt: I wanted to find out whether the most painful stings are also the ones that can do the most damage. We could already measure the damage a sting inflicts by a variety of different methods, but we had no meaningful way to measure the pain.

One method entomologists use to AVOID getting stung by insects is 'aspiration' – gently hoovering a bug into a tube-fed container known as a pooter

How does the index work?

The index records how much pain an insect sting causes so that we can make scientific comparisons between different species’ stings. I chose the four-point scale because it’s hard to distinguish between levels of pain in finer detail – on a 10-point scale, say.

Do you go out of your way to get stung, or is it unavoidable?

I usually get stung in the process of studying a particular insect species. Only very rarely do I have to provoke a sting, and in those cases – when the insect is unwilling to sting – the sting isn’t very painful.

Dr Schmidt holding a tarantula hawk wasp - the Largest wasp species – whose sting is rated as an excruciating 4

Has your pain threshold for stings increased over the years?


Which sting most surprised you?

Several surprised me. Most were surprising because they didn’t hurt as much as I expected. Based on reports of other scientists and early explorers, I assumed that the matabele and giant stink ants of Africa, the bulldog ants of Australia and especially the slender twig ant from Asia would be hugely painful. None of these hurt nearly as much as I’d anticipated.

One that hurt more than I expected was an ordinary honey bee – but that was when it flew into my mouth and stung my tongue!

Do you travel a lot as an entomologist?

I do. On one of my most memorable trips, I arrived at a caravan camp in Limpopo, South Africa, to discover a great wealth of insects everywhere in the beautiful park grounds. There were huge predacious ground beetles, myriad amazing velvet ants, astonishing giant velvet mites and even the occasional “big and hairy”, such as a serval [a type of wild cat].

Dr Schmidt travels a lot with his work studying bugs. Here, he is pictured atop a termite mound in Australia

What’s the best thing about being an entomologist?

The best thing is that you get to study some really cool creatures and make fascinating discoveries about them. Insects are everywhere and are so important – not only to our physical health and well-being, but also to our mental health and enjoyment of the world. One funny thing about being an entomologist is that some people confuse us with etymologists [those who study the origins of words]. I often wonder if etymologists also get confused with us!

Which of your sting descriptions are you most proud of?

One of my favourites is the Florida harvester ant, which, though it’s not aggressive and almost has to be forced to sting someone, still achieves a “3” on the index. I describe the pain as: “Bold and unrelenting. Somebody is using a power drill to excavate your ingrown toenail.” The club-horned wasp, on the other hand, which doesn’t even merit a “1”, is: “Disappointing. A paper clip falls on your bare foot.”

According to the index, the Most painful insect sting of them all is that of the bullet ant of Central and South American rainforests. Dr Schmidt has given it an unmatched "4+" and describes the sensation of getting stung by one as "like walking over flaming charcoal with a three-inch rusty nail in your heel"!

The Most painful insect sting in the world is that of the bullet ant, registering 4+ on the index

Dr Schmidt explains a little more about his mission to rate stings in the video below.

To find out more about Dr Schmidt’s Sting Pain Index, check out his book, The Sting of the Wild. As well as the worst culprits, you’ll also learn about insect anatomy and their motives for stinging.


Read the full interview with Dr Schmidt in Guinness World Records: Wild Things, out now!