Diseases of Honey Bees
Presented
By
The Ohio State Beekeeper’s Association
Diseases
•
Based upon date provided by the Ohio Department of Agriculture -- 2005
Brood Disease
American
foulbrood
Brood Disease
Good healthy brood
American foulbrood
2005 Apiary Statistics
From ODA
Colonies Inspected 21,389
Number with AFB
388
That doesn’t seem like many but this is a
serious disease spread very easily
and at some time or other
beekeepers will experience it.
American foulbrood
Brood Disease
American foulbrood
Young larva ingest the bacterial spores
when fed by nurse bees. The
spores then germinate and begin
to grow rapidly. Death to the
larva usually occurs as the pupae
stage is reached. Larva that die
turn a coffee brown and begin to
melt down into a gooey
mass. Housecleaning bees then
try to remove the dead larva and
in the process become
contaminated with the bacterial
spores that are now
dormant. The house bees then
carry the spores to other bees,
and the spores end up either in
the honey stores or are fed again
to new larva. Thus the disease is
spread within the colony rather
rapidly.
Brood Disease
American foulbrood
Robbing is one of the ways that
American foulbrood is
spread. Robbing bees will
take back contaminated honey
to their own hives which will
result in larva being fed with
spore laced honey. The
disease will spread to many
colonies within several miles
from the infected hive.
You should always check for
American foulbrood when
examining your hives. If you
are able catch this disease
early, further spread can be
prevented.
Disease
American foulbrood
The way to test for this disease is
to place a thin stick, twig,
straw into a cell with this
coffee brown gluey
substance. Stir and draw the
thin stick out. If the gluey
substance sticks and ropes, it
is most likely AFB.
You can also take a sample of
comb from this frame and
have your bee inspector send
it in for confirmation of AFB.
Disease
American foulbrood
Treatment:
If diagnosed as AFB, the colony
and bees can be treated in
Ohio with Terramycin or Tylan.
This must be used and
consumed by the bees at least
4 weeks prior to a honey crop.
These only mask the disease.
The spores are not killed and
can re-infect the hive
The only sure way to get rid of it…
Disease
American foulbrood
Treatment:
Burn ……… This is the only way to
effectively destroy the disease.
Other chemical treatments only
mask the symptoms and it can
return at a later time.
However, this is a disease you must always realize is
in your hives at some point in time– some bees
have built up a resistance to AFB. If you burn
and your neighbor doesn’t which is legal in Ohio
if he treats with chemicals, have you gained
anything by burning?
Brood Disease
European
foulbrood
Brood Disease
Good healthy brood
European foulbrood
2005 Apiary Statistics
From ODA
Colonies Inspected 21,389
Number with AFB 13
European foulbrood
Brood Disease
European foulbrood
Cause
European foulbrood (EFB) is a brood disease of
honeybees caused by the bacterium
Melissococcus pluton.. Larvae are most
susceptible to infection when they are less than
48 hours old, and usually die while still in the
coiled state. Poor nutrition and severe stress,
for example insecticide poisoning, often cause
this disease to break out. The larvae first turn
yellow then brown in color. The disease is
usually noticed in early spring, and to a lesser
extent in autumn.
Brood Disease
European foulbrood
Multiplication and spread
The bacteria multiply vigorously in the gut of larval bees
which have been given food contaminated with M.
pluton.. As with American foulbrood, EFB can also be
spread by:
bees robbing infected hives
transferring infected honey supers and combs to clean
hives
using contaminated beekeeping equipment
feeding infected honey and pollen.
Brood Disease
European foulbrood
Treatment: Good beekeeping hygiene will keep this
disease in control, however, if a hive should be
found with EFB it is important to prevent any
robbing of the hive and frames from this hive
should not be transferred to any other
hive. Treatment with terramycin – A colony
recovers rapidly. The effect of EFB is to reduce a
colonies bee population and thus reduce a
honey crop. Also consider requeening if the
bees are not cleaning up the disease.
Brood Disease
Chalkbrood
Brood Disease
Good healthy brood
Chalkbrood
2005 Apiary Statistics
From ODA
Colonies Inspected 21,389
Number with Chalkbrood 596
Chalkbrood
Brood Disease
Chalkbrood
Identification: A fungal disease caused by
Ascosphaera apis . It is now found
throughout the United States. It is a
disease of stress in the early spring to
early summer. Severe cases can be
found in the comb later in the
year. Often the bees will try to remove
the mummy larva -- it is called chalk
brood because the mummies are chalk
like in appearance and touch. These
mummies can often be seen at the
entrance of the hive.
Brood Disease
Chalkbrood
Treatment: There is no chemical approved
treatment for this disease. The best
management plan would be to: strengthen a
weak hive with more brood and bees,
replace the queen (literature indicates that it
might be genetic characteristic) with a
queen of known hygienic behavior. To
avoid spreading chalkbrood, you can avoid
using pollen from a chalkbrood hive for
supplemental feeding and avoid
mixing frames of comb from a chalkbrood
hive with other hives you may have.
Insect pest in hives
• 2005 Apiary Statistics
• From ODA
• Colonies Inspected
21,389
•
•
•
•
Varroa Mite 6,720 colonies
Tracheal Mite 41 colonies
Small Hive Beetle 539 colonies
Wax moth
n/a
7000
6000
5000
Varroa
Trach.
SHB
Wax moth
4000
3000
2000
1000
0
Varroa Trach.
SHB
Wax
Moth
Insect pest in hives
Varroa Mites
2005 Apiary Statistics
From ODA
Colonies Inspected
21,389
Varroa Mite 6,720 colonies
The greatest threat to all beekeepers
in Ohio. It has been
responsible for more
beekeepers leaving the hobby
than anything else. This is the
honey bees # 1 enemy.
Insect pest in hives
Varroa Mites
Identification: This mite is
known as varroa
destructor. Varroa
mites can be found in
the United States
except Hawaii. The
mite is small but can
be seen with the naked
eye. Mites are about
the size of a pin head
and are reddish/brown
in color.
Insect pest in hives
Varroa Mites
They can be detected by several methods.
•
One is with varroa screens and a sticky board. Mites fall
through the screen onto the sticky board where then can
then be detected and counted to determine the
infestation level.
•
The second method involves checking drone brood for
mites.
•
The third method involves scooping up 100 or so bees
and subjecting them to a sugar roll or ether roll test. The
sugar roll test does not kill the bees and is
preferred. The method is simple. Scoop up the bees
into a pint jar, add powdered sugar (a tablespoon will do)
and shake and roll the jar.
•
Varroa mites will drop off the bees to the bottom of the
jar where they can be counted.
Insect pest in hives
Varroa Mites
They can be detected by several
methods.
•
Most common is the sticky
board test. A protective
screen is placed over the
sticky board and the sticky
board is left in the hive for a
period of 24 hours. The
mites on the sticky board
are then counted. A sticky
board can be made easily by
taking a sheet of wax paper
and coating it with vegetable
oil. Lay it on the bottom
board and place screen over
it. This will also detect
chalk brood.
Insect pest in hives
Varroa Mites
They can be detected by
several methods.
•
Second method
involves checking
drone brood for mites
like shown in the
picture. You can check
individual capped
drone cells -- use your
hive tool or a cappings
fork to remove pupa
from the drone comb.
Insect pest in hives
Varroa Mites
They can be detected by several
methods.
•
Third method involves
scooping up 100 or so bees
and subjecting them to a
sugar roll or ether roll
test. The sugar roll test
does not kill the bees and is
preferred. The method is
simple. Scoop up the bees
into a pint jar, add powdered
sugar (a tablespoon will do)
and shake and roll the
jar. Varroa mites will drop
off the bees to the
bottom of the jar where they
can be counted.
Insect pest in hives
Varroa Mites
They can be detected by
several methods.
•
Remember that more
than 85% of the mites
in a colony are in
capped brood cells and
not visually detectable.
If a bee inspector see
one mite, he or she will
indicate on inspection
report that all hives in
your bee yard are
infected.
Insect pest in hives
Varroa Mites
Treatment:
I can not tell you
exactly what will
work. A number of
products are
available for the
beekeeper. Some
work at times and at
other times have no
apparent effect.
Insect pest in hives
Varroa Mites
Treatment:
In general use:
Apistan strips (10% fluvalinate)
CheckMite+ (Coumaphos)
Formic Acid
Sucrocide
Apiguard (Thymol)
Powdered sugar
Also no chemical means such as
drone comb capture frames.
Don’t ask me which is best!
Insect pest in hives
Tracheal Mites
2005 Apiary Statistics
From ODA
Colonies Inspected
21,389
Tracheal Mite
41 colonies
Still a problem. Introduced in the
mid 1880’s. A real problem in
the early 1990’s in Ohio.
Insect pest in hives
Tracheal Mites
Identification: This mite is
named Acarapis woodi
. It was first identified
as the Isle of Wight
Disease. This mite has
become well
established in the
United States except
Hawaii. These mites
can be observed under
a microscope. They
are found in the
tracheae of adult
honey bees.
Insect pest in hives
Tracheal Mites
Highly infested hives usually die in
the fall or winter. One may find
few bees in a dead hive. This
is contrary to starvation when
most of the bees will be on the
face of the comb -dead. Early detection is
important. If the beekeeper
notices a rapid decline in
population, the situation is
already out of hand.
Fortunately, breeding better queen
bees with resistance to the
tracheal mite has reduced the
tracheal mite problem from
what it was 10 years ago.
Insect pest in hives
Small Hive Beetles
2005 Apiary
Statistics
From ODA
Colonies Inspected
21,389
Small Hive Beetles
colonies
539
Insect pest in hives
Small Hive Beetles
Identification: The SHB is found primarily in
the Southern states of the United
States is now found in many other
states especially states that import
bees for pollination. It is called:
Aethina tumida .
The small beetle is black and can be found
moving rapidly inside the hive when
exposed to sun light.
The Larvae may be mistaken for wax moth
larva but they do not spin cocoons as
the wax moth larva and leave a slime
trail within the hive. They can make a
complete mess of a hive which can
result in the loss of comb in the
frames and loss of honey crop. This
beetle seems to prefer weak hives
especially queen less hives to do its
damage.
Insect pest in hives
Small Hive Beetles
Treatment: Several treatments are
available to the beekeeper for
SHB.
First, a ground drench - SHB larva crawl
from the entrance of a hive and
pupate in the ground around the
hive stand. The product is called:
GardStar®. Always read label
directions for the use of the
product.
Second, CheckMite+ - TM a strip which
controls both SHB and Varroa
mites.
Third , various trap designs. This is the
trap designed by Mike Hood.
Insect pest in hives
Wax Moths
2005 Apiary
Statistics
From ODA
Colonies Inspected
21,389
Not reported in data collected by
ODA.
Insect pest in hives
Wax Moths
Identification:
There are two
general types found in the
United States: Galleria
mellonella L. the Greater
Wax Moth and Achroia
grisella F. the Lesser Wax
Moth.
Both do considerable damage to
bee hives that are in weak
condition and to stored
comb in supers. It is the
Wax worms are a serious
problem in warm weather
and dark conditions. They
can do a lot of damage in a
very short period of time.
Insect pest in hives
Wax Moths
Treatment: Wax moths attack weak
hives. Strong hives will kept
them under control.
Wax moths do not like
light. Exposing equipment to
light, closing up equipment
tightly and fumigating with
"Para-moth" (ParaDichlorobenzene crystals) a
product available from most
bee suppliers, and using
biological control such as
Bacillus thuringiensis.
See Ann Harman’s article in
February 2007 Bee Culture
Magazine. A good investment
in beekeeping is to subscribe
to the bee magazines.
Other Minor Diseases
Nosema A protozoan disease caused by Nosema apis. Although
most beekeepers do not consider this a major disease, I am
going to list it as such. It is very damaging to colonies of bees
that over winter in the north. It kills more hives of bees than it
is given credit for. You can not see this disease because it is
caused by spores which germinate in the midgut of the honey
bee. Symptoms include: shortened life span, fecal deposits on
the inside of the hive and often on the outside of the hive. One
way to check for nosema is to pull the digestive tract out of a
honey bee. Healthy digestive tracts are tan in color. If it is
white, the bee is usually infected with nosema. Treatment : The
antibiotic Fumagillin sold as Fumidil-B mixed with sugar syrup
and fed to the bees in the fall and spring. Literature suggest 1
gal. of syrup per hive. 0.5 grams are mixed with 6 gallons of
syrup to feed 6 hives. This is an adult bee disease.
Other Minor Diseases
Sacbrood
Identification: It is a viral infection of the larva and is
named after the sac-like appearance of dead
larvae. The skin of the larva is tough and rubbery and
if pulled from the cell with a pair of tweezers, will look
like a thin sac covering the dead larva. It is not a
common bee disease. Treatment : There is no
treatment for viral diseases. Just use good sanitary
beekeeping practices while working with bees and if
you find a colony with this disease, do not mix other
hive frames etc. with this colony. Replacing the
queen with a queen from less susceptible stock may
help.
Other Minor Diseases
Paralysis
Identification: It is a viral infection of the adult
bee. Often the beekeeper will notice that the
bees are hairless or very glossy as in old
age. One might notice a number of bees
crawling on the ground around the hive
entrance, or trembling on the landing board
unable to fly. I should point out that the
trembling could be a symptom of pesticide
poisoning as well. In some cases the bees
just disappear or dwindle away.
Treatment: No treatment for a viral
disease. Requeening with good stock may
help.
General Treatments
•
The following chart is from the 2007 Dadant Catalog. If you don’t have a copy of this
catalog, you should request one from Dadant.
General Treatments
•
From Dadant catalog 2007