Yes, that certainly is a reasonable interpretation. But it still wouldn't be about the well being of individual microbes, but the ecosystem as whole. I am sure the biolfilters in transporters routinely murder countless microbes.I was always under the impression that her objection had to do with the idea that a planet harboring a microbe could be one that would develop life and an ecosystem in the future much the same way that earth has done. Therefore she objected almost on the basis Of how the prime directive is built, around not interfering with the evolution of other worlds.