The total bacteria mass [they] find represents about 0.3% of the overall body weight, significantly updating previous statements that 1%–3% of the body mass is composed of bacteria or that a normal human hosts 1–3 kg of bacteria [NIH. NIH Human Microbiome Project defines normal bacterial makeup of the body. Natl Institutes Heal 2012. (accessed January 3, 2015). link 5th paragraph from top].
Maybe… https://www.statnews.com/2016/04/15/parasite-benefits-humans/ https://www.theguardian.com/lifeandstyle/2010/may/23/parasitic-hookworm-jasper-lawrence-tim-adams https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1005039
I meant that the question wasn’t about the positive effects of parasites but about the number you mentioned.
https://www.nih.gov/news-events/news-releases/nih-human-microbiome-project-defines-normal-bacterial-makeup-body
They were asking about mites, not bacteria, which is what the pictures are depicting.