Why Every YBKA Member Should Get Themselves to a Healthy Bees Day

A report from Richard Senior, YBKA member, on attending a Bee Farmers Association-hosted Healthy Bees Day, run by the National Bee Unit.

I went along not quite knowing what to expect from a day billed as “Healthy Bees,” organised by the Bee Farmers Association and run by the National Bee Unit. What I got was two hours with Jack Silberrad, Regional Bee Inspector for Eastern England, that left me rewriting half of what I thought I knew about disease management, and a hands-on afternoon workshop to go with it. If you get the chance to attend one of these yourself, take it. Here’s why.

European and American foulbrood: the disease that hides

Jack opened with European foulbrood, and the thing that stuck with me most was how patient it is. EFB doesn’t set out to kill the larva it infects. It just competes with it for food, quietly, for as long as the colony stays healthy. No symptoms, no drama, nothing to see. It can sit in a colony, get moved between frames, boxes, hive tools and gloves, even travel to other apiaries, all without showing a single sign. It’s only when stress arrives, rising varroa, a poor season, a dry summer with little nectar, that the larvae start to twist, discolour, and lose their shape, and the colony tips into real trouble.

That long symptom-free window is exactly why it spreads so easily and why “I’ve never had disease here” means almost nothing. As Jack put it, absence of evidence is not evidence of absence. An area that looks EFB-free might just be an area the bee inspector hasn’t reached yet.

He gave us the practical diagnostic gap between the two foulbroods, and it’s worth remembering: EFB shows before capping, in the open brood, so there’s no point uncapping sealed cells looking for it. American foulbrood shows after capping, once the larva has pupated, which is also why it’s far more aggressive and far more obvious once it takes hold. For EFB, the tell-tale sign is what he called the “mayonnaise gut,” a distinct white gut visible when you dissect a suspect larva with tweezers. See that, and you’re almost certainly looking at EFB. For AFB, it’s the ropey test: uncap a cell, poke a matchstick in, and if it strings out into a thread, that’s your answer, no question about it.

What really landed for me was the biosecurity picture. EFB survives on comb for up to three years and in stored honey for eighteen months, quietly waiting on a hive tool, a glove, a spinner, or the gear stick of your van until it lands back on a healthy colony. Jack’s own experience of losing colonies to EFB in Cambridge came with a hard-won lesson: keep your high-risk and low-risk apiaries separate in your workflow, mark and track your kit by apiary, don’t hoard old brood frames “just in case,” and clean your hive tools properly. He shared the recipe the NBU now recommends: a kilo of washing soda in four and a half litres of water as a base cleaning solution, with 150ml of standard bleach added to reach full sterilising strength, made up fresh and used within twenty-four hours.

And crucially, report it. Beyond the legal duty to do so, reporting gets you free expert help from an inspector, strain typing that can trace where a problem came from, and access to the Bee Disease Insurance scheme, which now pays out on old and part-used kit destroyed as part of treatment, not just full frames.

Worth pausing on the lateral flow devices too. They’re back on the market at around £10 a pop, single-use, and Jack was straight about the catch: the moment you crack one open, you’re already declaring a suspicion of disease, and under the legislation that’s the point you’re obliged to report it anyway. So if you’re reaching for an LFD, you should really be reaching for your phone instead. Lay the frame down, get a clear photo looking down into the cell, and WhatsApp or email it straight to your bee inspector. You’ll usually get an answer within a day, often faster, and it costs nothing. If you suspect it, report it. That’s the rule, and it makes the tenner in your pocket largely redundant. 

Varroa: still the number one killer

The second session turned to varroa, and Jack was blunt about it: even with everything we already know, varroa remains the leading cause of colony death worldwide, and it’s very likely the underlying reason behind a lot of the winter losses we simply write off as normal attrition.

A few things reframed how I think about managing it. Phoretic mites, the ones riding visibly on a bee’s back, make up less than one percent of the mites actually in a colony. The rest are tucked under the bee’s exoskeleton, feeding on the fat body, which is the organ that governs a bee’s ability to survive winter and rear brood. And the drift is staggering: in July, as much as 40% of the varroa in a given colony didn’t originate there at all. It arrived on bees drifting in from neighbouring apiaries. That single fact changes how early and how thoroughly you might want to treat, because your neighbour’s untreated colonies are effectively treating yours too, just not in the way you’d like.

We went through the symptoms that flag a serious infestation: parasitic mite syndrome, with partially uncapped, nibbled brood and starving pupae; deformed wing virus; chronic bee paralysis, which leaves infectious virus in dead bees on the hive floor for up to a year; and sacbrood, which at a late stage can look enough like EFB to fool an experienced eye, something Jack called “pseudo-EFB.”

He then ran through the licensed treatments, of which there are only around a dozen in the UK, covering oxalic acid dribbles and vaporisation, Formic Pro, Api-Life Var, thymol-based treatments, and Apivar strips, weighing up efficacy, temperature limits, withdrawal periods, and whether supers need to come off. The point he kept returning to was resistance: use the same treatment repeatedly and you’re selecting for the mites that survive it, which is exactly how pyrethroid and Apivar resistance took hold in the first place. Cycling treatments, using only licensed products at their proper concentrations, and recording every application, even something as simple as a sugar roll, isn’t box-ticking. It’s what keeps the treatments working at all.

Jack’s top tips for keeping disease at bay

A few practical habits came up again and again through the day, the kind of things that cost little but make the real difference between catching a problem early and finding it too late. Some are familiar, some may be new to you.

• Manage varroa judiciously, above everything else. Jack was blunt that this is the single biggest lever a beekeeper has. Varroa is the leading cause of colony death, and it’s also the main trigger that pushes EFB from a quiet, symptomless presence into an active, colony-collapsing infection. Keep varroa low and a lot of other problems simply don’t get the chance to develop.
• Inspect before you collect. Jack described a case where a whole batch of nucs turned out to be carrying disease, and by the time anyone noticed, they’d already been split across several apiaries. A quick check of the source colonies before you buy nucs, take on new stock, or accept a swarm can save you months of cleanup later.
• Burn old frames rather than reuse them. EFB survives on comb for up to three years and in stored honey for eighteen months. Old brood frames sitting in a shed “just in case” are a genuine reservoir of infection, not a harmless bit of kit. If you’re doing a shook swarm, give the colony entirely fresh foundation; with no capped brood for the first ten days, there’s nowhere for varroa or disease to hide either, so it doubles as a clean-up opportunity.
• Separate your operation by risk. Jack’s own experience after an EFB outbreak in Cambridge was that everything in his operation had become suspect because his high-risk urban apiaries and lower-risk rural ones shared kit and cropping order. Now he crops and stores kit for each separately, so if a problem does turn up, it’s contained to one part of the operation rather than the whole thing.
• Clean your hive tools and gloves properly. A quick wipe doesn’t cut it. The NBU’s recommended solution is a kilo of washing soda in four and a half litres of water as a base cleaner, topped up with 150ml of standard bleach to reach full sterilising strength, made fresh and used within twenty-four hours.
• Keep records of what’s moved where. Frames, boxes, gloves and hive tools all travel between apiaries over a season, often further than beekeepers realise. If a colony is diagnosed with disease, being able to trace where its kit has been in the last year or two is what allows you, and the bee inspector, to work out what else might be at risk.

Why it’s worth your day

What made the day valuable wasn’t just the content, though there was plenty of it. It was having a Regional Bee Inspector in the room to answer the awkward, specific questions that never quite get resolved by a book: what does real EFB versus pseudo-EFB actually look like under a hand lens, how do you package a sample properly, what’s actually in the varroa manual that the website makes so hard to find. Jack offered to email resources, record sheets, and reference guides to anyone who reached out, and that kind of direct access to NBU expertise is not something you get from reading a leaflet at home.

Healthy Bees Days exist precisely so that the gap between “I read about this once” and “I can diagnose this in my own apiary” gets closed. Given how much of managing both foulbrood and varroa comes down to catching problems early and knowing exactly what you’re looking at, that gap is worth closing. If YBKA members get the chance to attend one, I’d say go. You’ll come away a sharper beekeeper for it.