What should you do if you didn't know you had chigger bites until a week later?

Chigger bites: You don't need to do anything if the insects are no longer present. If itching, you could try over the counter Hydrocortisone cream.

Nothing, or ...: Chigger bites usually heal on their own within one to two weeks. In the meantime, control itching with an over-the-counter anti-itch cream, such as Hydrocortisone cream. Consult your doctor if your skin appears infected or if the bites seem to be spreading to other parts of your body.