Time to Visual Symptoms
The average time between a larva being fed spores and starting to exhibit clinical AFB disease symptoms is about 12.5 days. This is therefore the earliest that an infection can be detected visually. However, most colonies need considerably longer periods of time before they develop observable disease symptoms. The following table shows the length of time it took for honey bee colonies in one study to develop AFB disease symptoms after they were fed spores.
|Months after spores were fed||Percent of colonies developing AFB symptoms|
Symptoms of AFB can often take time to show
Just under half of the colonies developed disease symptoms within two months of being fed spores. However, approximately one-third of the colonies did not show any symptoms until three months or longer.
If the infections had come from spores in contaminated honey supers that were unknowingly removed from infected hives in the autumn and placed on clean hives the next spring, then the most a full brood check the following autumn would reveal would be about 85% of the infections that were created. The remainder would hopefully be identified the following spring, one and a half years after the honey supers were removed from the original AFB hives.
If AFB spores are introduced to a beehive in the spring, the disease may not be evident until the following spring.
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Our videos cover everything from your legal obligations to how to recognise AFB, collecting cell and bee samples and more.
There’s a lot of good information here, telling you everything you need to know about recognising AFB: the visual symptoms, smell of AFB and more.
New Zealand beekeepers have a number of legal obligations that must be met regarding AFB disease. Read the shortened list in summary, here.
Most hives become infected because bees, honey or equipment have been put into a hive from another hive that is infected with AFB. Lower your chances of an AFB infection by reading this section.
Find out when the next AFB Recognition and Competency Courses, or Refresher Courses are available. These are held throughout the year in various New Zealand locations across the South Island and North Island.