Its very woodsy here in the South and Ive been finding their corpses laying ontop of my covers in the morning.
I happen to have been taking Ivermectin horsepaste for the past 2 weeks and I'm pretty sure they're dying when they bite me. Also, their bites end up being no more than a red dot. No infection, no itch, nothing. They used to turn into painful, solid, infected knots that would last 3 months or more.
Ivermectin appears to kill the original perp, then kills the parasites and viruses they pass on to you.
Its a good pre-emptive measure that I have now seen real-world results with my own eyes.
I would be scared of liquid concentrate. With the paste or the pill, if you take 10 times the amount (basically several tubes?) you would immediately say to yourself "Now this doesn't seem right..." Even safer if you apply it topically.