#2 Killer of Bees
HONEY BEE VIRUS`
Right behind the devastating varroa destructor parasitic mite and before the age old brood disease concerns of AFB, the runner up in line on the assault of the honeybee is the #2 Enemy of Bees --- VIRUS`. These are the unseen killers which are very difficult for the beekeeper to detect.
For the most part, the prevalence and severity of viral infections are directly related to the presence of and level of the varroa destructor mite infestation in the colony. From learning about how varroa feeds on the bees you can understand how it is a prime carrier and transmitter of diseases and virus` from host to host. It is usual that when a viral infection shows up that high mite levels will also be present ... but not always. If you suspect a viral infection look for the mite first. Do an alcohol wash to determine the mite level. You may have a double punch happening that will be impossible for the colony to overcome.
Viral infections can be difficult to detect and takes a keen beekeeper`s eye to recognise that there is a problem before the hive completely collapses. There are some tell-tales of a viral infection. Stagnated or dwindling population, shiny/greasy hairless bees, bees with wrinkled wings, bees that are shaky or runny on the combs, bees writhling on the ground out front.
One of the ways that bees battle infections and infestations is through attrition. In serious overwhelming cases it may be outright absconding. What that means is that old, sick, dying bees are pre-programmed to leave the hive and get away as far as they can, never to come back. If they do not leave on their own they are hauled out and ejected by the house bees. Those bees may fly away leaving little behind or they may be unable to fly and the beekeeper will observe a writhing matt of bees on the ground trying to crawl away from the hive. In this way the sick bees take the contagions with them to reduce the prevelence and the viral load in the colony. The more sick that leave, the better the chances and the healthier the colony becomes. When a virus is present what you will notice is a hive that is stagnated visit to vist to visit. There may be lots of brood but there is no growth week to week. There may be a sudden and rapid dwindling. The most shocking experiences is to come upon a hive that was full of bees last time but is now nearly completely empty of bees with no obvious signs of disease in the combs or distressing debris on the bottom board. There is brood left behind and may even be a queen stranded with just a few bees left. It is like the bees just up and left without a trace. Well, that is exactly what they did! If and when you encounter this CCD (colony collapse disorder) type failure of a colony, you can be fairly certain that it was a virus. However you cannot be absolutly positive unless sample bees are sent to the National Bee Diagnostics Centre in Beaverlodge for analysis.
What to do about a virus infection in the beehive? Unfortunately there are no treatments for viral infections. There are no vaccines for honeybees. If you encounter a sick hive that has symptoms that point to a virus you have a very difficult decision to make. The infection may be left to run its course until the hive recovers or it just dies out. Or, the beekeeper may choose to be proactive and terminate the colony to stop the spread to other colonies.
For the recovery method; You can try adjusting the hive configuration and frequent boosting to see if the colony can survive the high attrition and pull through it. The risk is you may be just exposing those all of those new healthy bees to the virus, making more and more of them sick. For a sick hive it is also helpful to significanlty reduce the hive space, remove all the brood (potential source of the infection), and weekly add capped emerging brood from a healthy hive. Feed the colony high quality food. Place the hive in a sunny spot to ensure plenty of hygeinic flight opportunities. The success rate varies by what type of virus is present and the viral load in the colony. As a general rule of thumb; give any recovery attempt no more than a 50:50 chance ... they either make it or they don`t.
What you have to be more concerned about is the presence of other nearby colonies and the possible spread of the virus. Your choices when other hives are present are to move the infected hive to a quarantine area and try the recovery method. OR if the infection is widespread and obvious, it is best to choose termination. For termination a humane way is a pail or tub of cold soapy water. ALL of the infected bees, yes her royal highness too, are shook into the water to terminate the colony and contain the virus`. The emptied equipment is then sterilized by fumigation, acetic acid washing methods, or by simple exposure to good ventilation and sunlight UV. If a lot of equipment is involved, sterilization by radiation may be an economical solution to consider. The equipment can then be repopulated sometime later.
There is a good article on viral infections at the BC Government Bee website, Beekeeping Bulletins. Go there to review the many excellent publications put out by the Apiculture department. Here is a link to all of the bulletins.
For the article specifically on honeybee virus`, here is the link and also an embedded view below.
You can also find more articles on honeybee virus` online through google searches. I am hopeful that now that you are aware of the prevalence and severity of honeybee viral infections that you will use this as a trigger and a poke in the ribs to leap pad off into your continued studies of honeybee health and becoming a successful responsible beekeeper.