HONEYBEE DISEASES AND PARASITES
Kentucky Department of Agriculture, State Apiarist’s Office
100 Fair Oaks, Suite 252
Frankfort, Kentucky 40601
Office phone: (502) 564-3956
Cell phone: (502) 330-0797
State Apiarist's Web page: http://www.kyagr.com/state_vet/bees/index.htm
VARROA MITES: Chemical control
Chemical Control of varroa: There are many different chemical control products (miticides) labeled for
use in controlling varroa mites in Kentucky. Choosing the best product for your hives involves several
considerations, including: efficacy (how well does it kill varroa mites), safety (both for humans and honey
bees), ease of application (and this may be affected by how many hives you have and whether they are
located at your home or in an outlying beeyard), and cost (which may be more of an issue if you have a
large number of hives). Most labeled products are effective; however, some have had their efficacy
reduced due to long-term use and the resulting development of resistance in mites. In addition, some
products, classified as “conventional agricultural pesticides,” may have detrimental effects on honey bees,
including sub-lethal cumulative effects as a result of long-term usage. Remember, miticides are pesticides
used to kill an insect (varroa) living on another insect (honey bees).
We may classify these chemical miticides into two categories: products in which the primary active
ingredient is an agricultural pesticide, often used on other parasites in other types of agriculture; and
newer miticides designed specifically for varroa mites in honey bees. Two older strip type products,
Apistan and CheckMitePlus, as well as one newer product, Hivastan, belong to the first category. Newer
miticides which are not used in agriculture for non-honey bee parasites include the newer fumigant
products, Apiguard, Api Life VAR, and Mite Away Quick Strip, and also HopGuard, a very new product.
The older varroa strips products, Apistan and CheckMitePlus, are plastic strips that contain a
conventional agricultural pesticide. These strips are placed by the beekeeper into the hive between the
frames. The bees, and thus the mites, come into contact with the chemicals on the strips, and the mites
are killed by contact. Varroa mites have become HIGHLY resistant to both these older strip products. It is
highly likely that these products will be of limited use in controlling varroa due to resistance issues. In
addition, there is great concern about negative effects of these chemicals on the health of our bees,
especially regarding queen and drone fertility and other long-term sub-lethal effects.
Hivastan, a more recently labeled product, is also a conventional agricultural pesticide. It is formulated as
a paste and applied as a patty. As bees work to remove the material from the hive, both they and the
mites come into contact with the active chemical, which is lethal to mites. Though it is another
conventional pesticide, no adverse effects on honey bees have yet been reported from its use.
A newer class of varroa control chemicals acts primarily by permeating the hive as a gas (though some
also work partially by contact) and killing the mites as a result of fumigation. Varroa mite resistance in
these products – Apiguard, Api Life Var (thymol products), and the Miteaway Quick Strip (a formic acid
formulation) – is not an issue. In addition, these are considered less toxic chemicals, most being derived
from natural materials (like the herb thyme), and are thought to be much safer for honey bees. However,
being fumigants, their use is constrained by temperature requirements. All three have different
temperature ranges at which they are effective. If it is too cold, the chemicals will not vaporize and are
less effective; too hot, and they dissipate into a gas too quickly and will drive the bees from the hive.
However, in Kentucky, fall temperatures are often ideal for using the newer fumigant products.
PLEASE NOTE: The following information is general information about these individual products.
Complete information is contained on the label that accompanies the product when purchased.
Remember: It is very important, and it is the law, to read and follow ALL instructions that are on
the product label.
Api Life VAR: Api Life VAR was the first of the lower toxicity pesticides that were introduced (2003) for
varroa mite control in the United States. Primary active ingredient is thymol; also contains eucalyptus and
camphor. Ingredients are contained on an inert tablet, which is placed on the top bars of the hive. Mode
of action is as a fumigant. The label specifies use when average daily temperatures are between 54°F
and 90°F (warning on use above 90°F). Three applications required (initial followed by two additional
Apiguard is another thymol pesticide for varroa mite control; mode of action is also as a fumigant. Label
states use when daily maximum temperature is above 60°F. Product is sold as gel in metal trays with
peel-off lids (tray is placed on top bars of top brood box). Sold in package sufficient to treat five hives or
as a bulk tub (applied with spatula onto paper card), which treats about 40 hives. Two applications of
Apiguard are required.
MiteAway II Quick-Strips (MAQS)
MiteAway II Quick-Strips (MAQS), another fumigant formulation, are strips containing formic acid, a
powerful yet naturally occurring chemical. This manufacturer previously distributed a formic acid product
as a pad product; that product has been discontinued. Strips are placed across the tops of the brood
frames. Label states outside daytime temperature highs should be between 50-92ºF on days of
application. Single application required. This is a new product in 2011.
HopGuard Another new (2011) miticide derived from hop plants; the active ingredients are described as
food grade natural products and “Potassium Salt of Hop Beta Acids.” Application is via a cardboard strip
containing the oil, which is placed between brood box frames. Single application required.
Hivastan: A fairly new product (new in 2008) labeled for varroa mite control, active ingredient is a
pesticide called fenpyroximate, which is delivered as a thick paste, for use as a patty. Hivastan is sold to
beekeeper in a bucket; the patties are made up by the beekeeper and placed in the hive in a manner
similar to that of grease patties used for tracheal mite control. The bees treat the patty as a foreign object
and remove it from the hive. This handling process transfers the fenpyroximate to the bees and to the
varroa mites on the bees. Fenpyroximate is a conventional agricultural pesticide, though adverse effects
on honey bees have not been reported. Hivastan is popular with beekeepers with large number of hives
due to ease of a single application.
Older products (varroa mite resistance to these products is a serious problem)
Apistan: Applied as a plastic strip, which contains the active ingredient fluvalinate. Strips are placed in the
brood boxes, one strip for every five frames of bees. Works as contact pesticide; mites are exposed to the
chemical when bees come in contact with the strips. Apistan was first registered as a varroa control
product in 1992; varroa has developed a high degree of resistance to fluvalinate. In addition there, are
serious concerns about toxicity to honey bees.
Checkmiteplus: Also a strip product containing a pesticide active ingredient, in this case coumaphos.
Application similar to Apistan. This product has also been in long use (10 years), and resistance of varroa
to Checkmiteplus, as to Apistan, is a serious issue. Side effects affecting fertility of drones are also of
concern (definitely NOT recommended if rearing queens).
Labeled product not available in Kentucky
Sucrocide (Sucrose Octanoate): Classified as a biopesticide and is considered safe (for honey bees).
However, is labor intensive to apply; it must be mixed with water and sprayed onto all brood frames in a
hive. As a result, sales of this product have been low, and the United States distributor does not label this
product in Kentucky (it is available in some other states). Indifferent results from this product are reported,
further contributing to lack of interest by beekeepers.