AFB in the top bar hive
Margo, our One-Block Diet editor, told me to write something more
cheerful about bees. Something cheerful because, well, it seems like
it’s just always bad news in the apiary. Ants, mites, small hive
beetles. We’ve battled them all. And now we’ve lost our top bar hive
Califia to what appears to be American Foul Brood (AFB), poor ventilation, and a bad case of mites.
American foul brood is an awful,
horrible bacterial disease that infects
bee larvae, and kills them in their cells. It’s such an infectious
disease that, when found in the hive, all the comb, foundation, and
frames have to be destroyed, and the inside of the hive
“toasted” with a torch.
So here is something happier. I got to play with a propane
torch. That was fun.
It was NOT fun learning about AFB. It’s like a plague, killing baby bees in their cells, and
is often spread from hive to hive by robbing bees and drifting bees (evidently bees
sometimes get confused, or decide to explore other hives, and often manage to
sneak past guard bees.)
We’ve yet to examine Veronica; the weather’s been too rainy.
So we’re keeping our fingers crossed that we don’t discover any foulbrood in
her. Treatment is complicated, and involves antibiotics, which make the honey
inedible to humans, and we’re right on the verge of a nectar flow (if it ever
stops raining.)
We’ve got a new package of bees coming soon to rehive one of the empty
hives. Now there’s a really cheerful thought.

Surprised that the AFB did not spread to Veronica–how far apart were the two hives?
We had the same symptoms as Tina K., although we had other complications too: bees with head in cells (starvation?) and a heavy mite load. San Mateo Beekeepers Guild agreed it looked like AFB.
Ropey brood, foul smell, had other beekeepers take a look. Followed Dr. Musssen’s recommendation on the Tylan. It’s used to treat AFB and we never saw it again. We torched inside of boxes and rotate combs out routinely. Never saw any signs of it again. I think you can have spores in hives that have never even shown symptoms. We don’t move bees around to different yards. They just stay in one place
The spores live this side of forever.
How did you verify that you had AFB?
Sorry to hear about the AFB! We saw that once. We treated with tylan (the bees were still alive) and it seemed to clear it right up. We never saw any foulbrood after that time and that was about 4 years ago. You should only treat with Tylan IF you see AFB, not as a prevention. Using antibiotics as prevention causes the bacteria to develop resistance, as it did with terramycin.