Chiggers

Chiggers are the larvae of tiny mites (family Trombiculidae) that live in tall grass and weeds and feed briefly on people and animals, leaving intensely itchy red bumps. They are about 1/150 of an inch long — orange-red, six-legged, and almost invisible on skin — and in the US they are a nuisance, not a disease threat.

They're also called red bugs, harvest mites, or jiggers. Most of what people "know" about them — that they burrow, that nail polish suffocates them, that they live in beds — is wrong, and getting it right saves a lot of wasted effort.

What chiggers look like

A chigger larva is an oval, slightly hairy speck, orange to bright red, with six legs (adult mites have eight; the larva gets its fourth pair later). Size: 0.15–0.4 mm, smaller than the period at the end of this sentence.

How to actually see them:

• Stand on a white board, paper plate or white sock in a suspect area for a few minutes. Chiggers climb up and show as moving red-orange dots.
• Use a 10x hand lens. With the naked eye they look like dust that moves.
• Adults (rarely noticed) are bright red, velvety, figure-eight-shaped mites about 1/20 inch, walking on soil in spring. They don't bite.

"Baby chiggers" is what people call the larvae — and they're the only stage that bites.

Chiggers vs clover mites and other look-alikes

If you can easily see a red mite crawling on your windowsill, it's a clover mite, not a chigger. If something tiny is still attached to your skin days later, check our page on seed ticks.

Where chiggers live

Chiggers are found across the US but are worst in the Southeast, South Central states and lower Midwest — Texas, Oklahoma, Arkansas, Missouri, the Gulf Coast, Florida, and up through Ohio and Indiana. In Texas and the Deep South the season can run from April into October; farther north, June through August.

They don't spread evenly. Eggs are laid in soil, and larvae climb to the tips of vegetation to wait for a host, in "mite islands" where conditions are right:

• tall grass and weeds, especially unmown lawn edges and fence lines
• overgrown ditches, berry patches, brush piles
• the transition zone between woods and field
• damp, shady ground with leaf litter

Short, sunny, mown turf is a poor habitat. That's why one person picks up dozens of bites walking the fence line while someone on the patio gets none.

Life cycle

Egg → six-legged larva (the chigger) → eight-legged nymph → adult. Only the larva feeds on vertebrates — rodents, birds, reptiles, dogs, and people. People are an accidental host: a chigger can't complete feeding on us before it's scratched or washed off. Nymphs and adults are free-living predators in the soil. One generation per year in the North, up to three in the South.

How chiggers bite (and why they don't burrow)

Chiggers crawl until stopped by tight clothing — sock lines, waistbands, behind the knees, groin, armpits — then attach to a hair follicle or thin skin. They inject saliva with enzymes that break down skin cells and drink the liquefied tissue. Your body hardens the tissue around the feeding site into a tube (a stylostome), which is the red dot you see.

The itch usually starts 3–6 hours after the bite and peaks in 1–2 days. By then the chigger is usually long gone. So nail polish, bleach and alcohol on a bite do nothing to "suffocate" it — there's nothing there. See chigger bites for pictures and what helps the itch.

Are chiggers harmful?

In North America, chiggers are not known to transmit disease (in Asia and the Pacific, related species spread scrub typhus). The risks here are:

• an itch intense enough to disrupt sleep for a week
• secondary skin infection from scratching
• in children, a seasonal "summer penile syndrome" — swelling from bites in the groin that looks alarming but is usually harmless; call the pediatrician if urination is painful.

Chiggers also bite dogs and cats, mostly on ears, belly and between toes. Outdoor pets and ground-feeding birds and rodents help keep chiggers established in a yard.

Are chiggers contagious? Can they live in your bed?

Not contagious — bites are an allergic-type reaction, not an infection that spreads. And chiggers can't establish indoors: they need soil and outdoor hosts. If a few hitch a ride on your clothes, they die within days. "Chiggers in bed" almost always means you're still itching from bites picked up outdoors, or the culprit is something else — bed bugs, fleas, or bird and rodent mites.

How to avoid chiggers

1. Repellent on skin: products with DEET, picaridin or IR3535 (20% or more for longer protection). Focus on ankles, legs and waist. See insect repellents.
2. Permethrin on clothing: treat pants, socks and shoes (not skin). It kills chiggers on contact and survives several washes.
3. Tuck pants into socks and wear long sleeves in brushy areas. Stay on trails; don't sit on grass or logs.
4. Shower and scrub with soap right after being outdoors, within an hour or two. This knocks off chiggers that haven't attached yet — the single most underrated step.
5. Wash clothes in hot water before wearing them again.

For yards, the fix is mostly mowing and clearing — see how to get rid of chiggers.

When to call a pro

A chigger problem in a yard rarely needs a contract. Consider a pest-control company or lawn service if bites keep happening after you've mowed, cleared brush and edges, and treated hot spots once — or if the property is large with lots of wooded border. Expect roughly $75–$200 per perimeter treatment (approximate; varies by region and yard size).