@BrianHjelleVirologist saw one time on NatGeo that those who lived in the wild (natives/indigenous tribes) have a much stronger immune system than those living in big cities. These indigenous people are exposed to all kinds of bacteria or virus through out their lives and their body have adapted for that,, versus those in big cities or urban environments..

Point is,, we need to build our immune system again, like those in the jungles have been doing. Some are even "resistant" to malaria!!