> Some subset of those colonies have suppressed AFB 

The use of antibiotics to prevent foulbrood is poorly understood by those who do not do it. An easy way to think of it is like this:

You have weed seeds in your garden, done deal. You cultivate on a regular basis, you don't have weeds. As long as you keep cultivating, you won't have weeds. If you do this long enough, all the seeds have germinated, and now you have a weed free zone until more seeds blow in.

If you use antibiotics against AFB spores which are present, you don't get AFB. This is NOT called a latent infection, but an absence of infection. The spores can germinate, just like the above mentioned weed seeds, but they cannot grow and propagate as long as antibiotics are present.

The issue of antibiotic resistance must be dealt with separately, but in my opinion, it arose from treating active infections, thus weeding out susceptible strains and allowing resistant strains to take over. This is sort of like going into the woods with a hoe and wacking whatever you can kill with a hoe. Pretty soon, you have a nice patch of (hoe-resistant) trees.

PLB

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