Previously unknown pathogens are being discovered years after they arrive in the United States.

Unfortunately Porthos has acquired an unknown pathogen on the planet surface and must be quarrantined.

The investigators asked Doctor X to identify six vials containing unknown pathogens.

Thus, by measuring how reflectance changes over time, unknown pathogens and their growth rates can be easily characterized and identified.

If the beast was infected with some unknown pathogen, he wanted a specimen left for analysis.

They would also develop new processes that could be used to quickly create drugs and vaccines to fight previously unknown pathogens.

It's common practice, but we've never tried to capture an unknown pathogen before.

They had succeeded in filtering out an unknown pathogen, something that had only been a theory minutes before.

An unknown pathogen was working its way into the roots, discoloring leaves and choking off the plants' water supply.

There was nothing he hated quite so much as an unknown pathogen loose in a population he was supposed to keep healthy.