One of our hives has European Foulbrood (EFB). That’s a bacterial infection (Melissococcus pluton) that kills off some of the bees before they’re born and weakens a colony. It’s considered a stress-related disease and moving hives can trigger it. It’s spread pretty much around the planet, is contagious between colonies and is a nuisance, but strong hives can recover on their own. If necessary, it can be treated with antibiotics, specifically oxytetracycline hydrochloride (OTC). Unfortunately the antibiotics can make their way into the honey so you shouldn’t extract honey for at least 8 weeks after treatment.
Identifying EFB can be a bit tricky as the symptoms aren’t really pronounced. The larvae curl up, change colour and/or look as if they have moved around in their cell. To be honest, I’d never have spotted it. But our apiarist, Bruce, made his living inspecting hives and identified EFB quickly and positively. Here’s a photo of the area he pointed out to me as proof of EFB. Judge for yourself if it’s obvious.
European Foulbrood
Bruce also decided it should be treated but he didn’t have the antibiotics or time to do it. So he dropped the OTC in our letter box with some simple instructions and left it to Frank and me to administer.
Yesterday we finally did. It’s a simple as could be. We just sprinkled a couple of tablespoons worth of the powder (OTC mixed with icing sugar) over the brood box (under the excluder). That’s it. The bees will do the rest by spreading the antibiotic around the hive as they feed and clean the brood.
Spreading OTC on a hive infected with EFB
Now we wait and hope the hive grows in strength, overcomes its bout of EFB and that no other hives become affected.
Laura Rittenhouse's Gardening Journal 
Very useful information and the photos were both very helpful.
I’m glad. Though without an expert, I wouldn’t be bold enough to identify this particular bee disease even having now seen it once. It isn’t as obvious as I’d like.
Thanks – thats useful information. I guess it wasn’t necessary to treat the other hives, as a preventative measure?
No, you don’t treat with antibiotics as preventative. Just like with humans, we don’t want to create drug resistant strains of EFB. So you wait and hope they all are strong enough to fight it off.
Oh, dear. We wish the hive a speedy recovery.
Thanks – me too!
I hope the treatment works and it doesn’t spread to the other hives.
A couple other hives are pretty weak and they’re the ones I’ll keep an eye on. The others seem really strong so shouldn’t succumb.
As beekeepers ourselves we know how devastating this can be, so are really sorry to hear this. Hope the antibiotics do the trick and the problem is cured.
Thanks. I’m sure they’ll bounce back in no time. In this climate, it’s a lot easier to be a bee (and a beekeeper).
sorry. 😦 looks pretty gross. hope it clears up soon!
Yeah, it is kind of gross. Deformed babies – eeewww.
so glad you had someone there to help. Good too that you are treating it before it spreads.
I was lucky to have zero problems with my own couple of hives. Now that I have so many to look after it is great to have help – I literally couldn’t do it without him.
Every beekeeper dreads this happening, hope the treatment works. Although I wouldn’t feel confident immediately diagnosing EFB, I think I would have spotted something was wrong, and given time I’m sure you will too. The larvae in the photos lack segmentation and look quite ‘swollen’. Lacking segmentation is never a good sign.
I realised the segmentation was wrong AFTER I zoomed in on the photos back in the calm of my office. No way could I spot that through my bee suit with a frame half covered in bees. I’m in awe of Bruce – it really took him a nanosecond to diagnose. Some day, maybe – or not 🙂
I know what you mean about the bees being distracting!