The earliest living things are over three billion years old and they have proven to be both a help and a threat to us. Bacteria and viruses have always been a part of our evolution. Every so often one will come along that simply overwhelms us and rather than just making us sick will kill thousands if not millions.

There are a variety of bacteria and viruses and multiple times when their variations have affected and killed many humans. It is this range and variability that makes them so effective and deadly.

Guest: Colin Cullis/Business Unusual Correspondent at Money show. 

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