Most humans, including you, belong to the 99.9999% of Homo sapiens that are isolated from the much smaller isolated groups left. North Sentinel Island, which is nominally governed by India, is home of one of the very few smaller ones. Its locals number in the few hundreds and have likely been there and rejected outsiders for thousands of years.
The Guardian had an article saying they were of the Stone Age, but I think their Iron Age began when they dismantled a nearby shipwreck. Are they also trading with outsiders? And not dying from our diseases?