Hello! I will assist you today. As someone who spends lots of time in the great outdoors I can tell you that what you describe re classic chiggers. Since you have had not contact with someone with scabies or visited high risk areas the chance of you having scabies is extremely low.
Given your activity the chance of chiggers is near 100%. The permethrin (an insecticide) will not harm you by using it but it will not likely help either.
The chiggers dig in deep and cause lots of itching as you already know. The best thing to do is to wash the area quite well and apply a clear fingernail polish to the bite areas. This will cause the chigger to die and will speed healing.
You can also apply lotions like those used for poison ivy or oak to help dry our these areas.
Are you there?
That is what I thought.
Would tecnu work as well on the impacted areas?
Tecnu is a scrub to remove the oil that causes the irritation and not really want you want. You can also use generic witch hazel oil found at any pharmacy over the counter and cheap.
It has been six days since I have been back, I doubt the chiggers are still alive - but it seems that a few new bites are surfacing. Do you recommend not doing the permethrin lotion?
The chiggers will dig in and then move to a new location. This is why you use the nail polish to suffocate them and stop the spread. The permethrin (the same stuff you use on garden plants to kill bugs) may help but very little. It will not have you if it is not scabies as I suspect it is not but it will be of very little help as well. That is up to you really. It is pretty cheap so if it makes you feel better feel free to use it.
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