Bad case of mites. Need some guidance.

Hello there,

As the title says, I've come across a bad case of mites on my coop, mostly due to the weird weather here in Portugal (heat waves, now rain, then heat waves...).

So far I've been spraying permethrin on them and the coop but one of the Brahma (who was broody as the 7 hells) is the worse case due to being on top of the eggs all day every day for weeks on end.

What can I try more apart from the permethrin?

Thank you!