Differential diagnosis

Other diseases can look like AFB

There are a number of problems affecting honey bee brood that have symptoms similar to AFB.

Diseases and conditions that can be mistaken for AFB include sacbrood, chalkbrood, parasitic mite syndrome and half-moon syndrome. This section describes the symptoms of these diseases and conditions, and explains how the symptoms differ from AFB.

Know the life stage of the honey bee

The first step is to become familiar with the life stages of a honey bee (Fig. 34–42) so that any abnormal symptoms will be recognised.

Effective differential diagnosis often relies on comparing a set of symptoms, rather than concentrating on a single symptom, and looking at a range of larvae and pupae in the hive.

If there is any question about the symptoms of a particular larva or pupa, the entire colony should always be checked for further symptoms. If a definitive symptom is found, the beekeeper should still confirm the diagnosis by searching for three or four more diseased larvae or pupae elsewhere in the hive.

Figure 34: A honey bee egg

Figure 35: A one day old larva Figure 36: A three day old larva

Figure 37: A cell being sealed

Figure 38: A cell containing a
prepupae (capping removed
for photo)

Figure 39: A white eyed
pupa (capping removed
for photo)


Figure 41: A cell containing a pupa taking on
adult colouration (capping removed
for photo)

Figure 42: An adult honey bee chewing
an opening in the capping of its cell

Differences between common diseases

See the major differences at a glance.

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