Trombiculidae: The Chiggers That Make You Itch!

Hard to see; hard to cure; best avoided.

Not the menace they are in some countries, like the south of the USA, but here in the UK all the same, are the nasty little mites known in Britain as Harvest Mites. Also known elsewhere as “Berry Bugs,” “Red Bugs,” “Scrub Bugs” and “Itch Mites.” Although related to ticks and arachnids, these microscopic nuisances don’t actually feed on our blood, but like to munch on our skin, and then only in the larval, or “Chigger” stage, the name most people will recognise.

As adults, a shiny, orange coloured, 8-legged insect, the mites do not bother us, nor other animals, as they feed on plants, but in the larval stage they are a world-wide pest, feeding on countless animal species, as well as other insects. The chigger doesn’t really bite, either, but it injects its digestive enzymes onto the skin, which dissolve the skin cells so they can suck up the liquid, forming holes, or “stylostomes.” This also tends to anesthetize the site and we don’t usually notice the attack until the chigger has dropped off; then the itching and local irritation can be severe.

The creatures are found anywhere there is plant growth, especially luxuriant, long stemmed grasslands where the chiggers like to wait until an animal host passes, dropping or crawling on them as do ticks. Their infestation of humans is purely accidental; they don’t target us, but neither do they seem to have any preferences as to what skin they feed on…maybe ours is rather sweet to them: a nice change from scientists telling us the sharks, etc., don’t really like the taste of human flesh!

We are lucky in the UK in often finding we get the more benign species of nasties. This is true again as the Harvest Mite chiggers don’t generally carry disease-causing bacteria. However, in parts of Central and South America as well as China and other Asian countries, chiggers are considered dangerous as well as being a nuisance. This is because they can carry bacterium which can cause Scrub Typhus, a nasty and potentially fatal fever.

An attack by chiggers leaves red, pimple-like spots all over the skin where they have fed. Although they itch quite severely, best not scratch as this will increase the irritation from the bite: calamine lotion is effective as are anti-histamines in the case of a severe attack. If the chiggers are still present, they can be removed individually with tweezers and a magnifying glass, or washed off with a strong soap and water, or salt and water, solution. Sea- bathing will also rid a victim of the pests. In fact, chiggers don’t like extremes of humidity: too wet or too dry an environment and the chigger will bugger off, which is why they aren‘t found in the desert or in rain-forest conditions; less of a worry anyway in the Amazon where you are more concerned with staying several yards ahead of an Anaconda.

Their family name, Trombiculidae, comes from the Greek, where the first person bitten was a peculiar trombone player in an Athens orchestra. (just kidding). It really means, “To tremble,” which is what victims do when they wake up covered in ugly red, itchy blotches! They have been with us for many hundreds of years, record of their nuisance value appears as far back at the 6^th. Century in China. They were first recorded and studied in our culture in the USA at the end of the 18^th. Century. The best way to discourage them is to keep grass short in the garden and be careful when walking around in conditions they favour. This is in the summer months in the UK and Northern Europe; in more salubrious climes, they are around all year long.

Facts and Myths about Chiggers

1) If the chigger is brushed off while feeding as most usually are, it cannot feed again and will probably die like a bee which has stung you.

2) They love to get in areas where it’s embarrassing to scratch, like the groin and around the anus. You will scratch anyway!

3) The feeding hole they make, now lined with hardened body cells, can itch for weeks.

4) Nearly everything you learn from your neighbours about chiggers is wrong.

5) They are actually members of the arachnid family and use similar enzymes as the spider does to dissolve its prey to feed.

6) You will hardly be able to see one chigger, but a group of the little red horrors is easily spotted (as they are spotting you!)

7) Chiggers can move around fast on their long legs. It takes a chigger about 15 minutes to climb from your foot to your waistline; that’s like you climbing Snowdon in the same time…and before you have had breakfast.

8) Mosquito repellents are effective in warding off the chigger; as are powder containing sulphur which they hate.

9) Sorry, neighbour, putting nail polish on a chigger won’t help because it actually left hours ago if you are itching and that’s the stylostome bite-site you’re gazing at with murder in your eyes.

10) Dousing yourself with gasoline and applying a match is a sure fire way to end the misery of chiggers, along with that of life itself! Be brave, they are the itching-most creatures on the planet, but it will soon be forgotten.