Researchers late last month published a very interesting article on viral and bacterial concentrations in the atmosphere. While the paper did not prove the viruses or bacteria detected were viable the concentrations reported do provide some evidence that high altitude relocation of microbes is possible. In the case of bacteria this has been well documented in such cases as Bacillus anthracis and Burkholderia pseudomallei.  While this isn’t the time to panic or make a SciFi movie considering it is likely 99.9% of these microbes do not pose a threat to humans or most other species, it does provide another avenue for natural movement of pathogens around the globe.