It is the honey bees social structure that defends against threats and
quickly spreads intruders they cannot overcome. Commercial apiaries complicate
the spread of disease by drifting of foraging bees from one hive to another. The
foraging bees can bring more than nectar and pollen to neighboring hives. It is
the beekeeper’s responsibility to frequently inspect
hives for indications of diseases, pests and parasites.
The most virulent disease is American foulbrood.
European foulbrood is not as devastating.
Chalkbrood is a fungal disease. Sacbrood is viral.
Purple brood is not a disease, but from summer Ti Ti. Ti Ti nectar and pollen
are toxic to brood. All of the previous diseases affect the brood stage. Nosema,
affects adult bees.
Varroa mites destroy the comb and leave feces
in the honey causing it to ferment. Varroa attach to the exoskeleton and
literally suck the life out of bees. Tracheal mites
attack bees internally. Recent research suggests Varroa and Tracheal mites
greatest significance is providing an entry point for Israeli
Acute Paralysis Virus and Kashmir Bee Virus.
Bears, mice, ants, wasps, skunks, and raccoons are all predators to honey
bees. Skunks scratch at the hive entrance at night to lure and eat guard bees.
Securing the hive together with a ratchet strap or two is as effective as
electric fences at dissuading bears and raccoons. Poisoning also weakens or
destroys hives. Chemicals meant to control diseases and parasites can be just as
detrimental to the bees.
American foulbrood (AFB),Paenibacillus
larvae, infects larvae up to three days old.
AFB is characterized by a foul odor and sunken capped brood. If you stick
a toothpick in a suspected cell and pull out a ropey mess, you have AFB. In the
United States infected hives are burned. Several antibiotics have been used to
prevent AFB but AFB is developing resistance. Moving the hive a few feet away
and shaking all the bees off the frames to return to a new hive in the old
location is used elsewhere but not condoned in the USA. New hardware and comb
eliminates or reduces the spread of spores that were present in the comb, honey,
pollen and brood.
European foulbrood (EFB), Melissococcus plutonius or Streptococcus
pluton, effects open brood and does not form spores like
American foulbrood. Requeening or a good
honey flow clears most cases of European foulbrood.
Chalkbrood, Ascosphaera apis, infects the gut of larvae
competing for food and starving the bee. Increased ventilation (screened bottom
board) and requeening are effective.
Sacbrood, Morator aetatulas, larvae die just before pupation. Sacbrood has no
characteristic odor and the cells are capped.
Chilled brood is not a disease or virus. It is most often caused by
beekeepers inspecting the hive on cold days or lack of nurse bees to keep the
Acute Bee Paralysis Virus, Dicistroviridae
family, is similar to the Israeli acute
paralysis virus, Kashmir bee virus, and the
Black queen cell virus. Israeli Acute Paralysis Virus is considered a cause or
contributing factor to Colony Collapse Disorder (CCD). Varroa and Tracheal mites
increase susceptibility to viruses. Kashmir Bee Virus is recently discovered and
not much is known about it. Black Queen Cell Virus is thought to be associated
with Nosema. Deformed Wing Virus is also associated with Varroa destructor and
associated with CCD.
Varroa mites, Varroa destructor, (1987)
are treated with Apistan, fluvalinate, or Checkmite, coumaphos, or
Mite-Away, formic acid. Screened bottom boards, drone sacrifice and
powdered sugar dusting are the non-toxic treatments. Varroa mites prefer drone
brood because of the larger cell size and longer gestation.
Powdered sugar dusting promotes hygienic behavior or grooming. Screened
bottom boards allow mites to fall away where they will not to another host bee.
Tracheal mites, Acarapis woodi,
(1984) live in the airways of bees. Mature female mites leave the trachea and transfer to young bees.Menthol and grease patties, 1 part vegetable shortening and 3-4 parts powdered sugar are the treatments.
Nosema, Nosema apis, invades the intestinal
tract of bees. Increased ventilation (screened bottom board) and removing honey
to feed sugar syrup are the natural treatments.
Small hive beetles, Aethina tumidae,
(1998) pupate in the ground outside the hive. Adult beetles enter the comb to
feed. Beetle feces gets in the honey fermenting and destroying it. Beetle traps
are effective because beetles run to dark spaces to avoid bees and beekeepers.
Greater wax moths feed on comb destroying it in
the process. Moths prefer darker comb with cocoons of former brood so changing
old comb every few years helps. A strong hive is the best defense. Storing combs
freezing or with paradichlorobenzene prevents moth wax destruction.
|Major honeybee diseases
|American foulbrood (AFB)
||older larvae and pupae (after capping)
||shotgun brood pattern, straight on cell wall
|dead brood have full smell
|dead larvae are soft, sticky and ropy
|sunken caps with holes in them
|European foulbrood (EFB)
||young larvae (before capping)
||shotgun brood pattern, coiled in cell
|dead brood have full smell
|dead larvae are pasty
||dead larvae have yeasty smell
|dead larvae form dry chalk like mummies
||dead larvae with tough skin forming sac with darkish liquid
||bees disoriented and wings not folded normally over abdomen
||similar to nosema
||older larvae, pupae and adult
||presence of mite on larvae and pupae