Looking back to the 1918 pandemic virus is a natural source...
Looking back to the 1918 pandemic virus is a natural source for us to try to understand and predict what we might be working with today in the context of H5 or some other pandemic.
Looking back to the 1918 pandemic virus is a natural source for us to try to understand and predict what we might be working with today in the context of H5 or some other pandemic.