Why do they have electrical signal? 2nd video

I was showing these people my voltage detector. When I put it on the hand of the female, she had a signal. The detector has 2 ranges, orange light for under 49volts, red for over 50volts. It doesn't not detect amps. Normally, some people (vaxxed) register when they touch a power source, but this time, she was not touching anything. But she had her booster shot 2 days before. Think about what can conduct this signal. But even more interesting is if you look for Nokia CEO telling a meeting at WEF that smartphones will be integrated into the body