Get Ready For The Mite-A-Thon! September 8 - 15, 2018

CATCH THE BUZZ     August 29, 2018

Spread The Word - Local Beekeeping Clubs And Associations Are Key To Making The Mite-A-Thon A Success!

September 8 to 15, 2018      

The Mite-A-Thon is a tri-national effort to collect mite infestation data and to visualize Varroa infestations in honey bee colonies across North America within a one-week window.  All beekeepers can participate, creating a rich distribution of sampling sites in Canada, the United States, and Mexico.       

OBJECTIVE: 1) To raise awareness about honey bee colony Varroa infestations in North America through effective monitoring methods. 2) Management strategies will be made available for discussion within bee organizations utilizing Mite-A-Thon partner developed information and outreach materials.     

PARTICIPANTS: All beekeepers in North America are encouraged to participate.


Encourage your members to participate in September, through meetings, newsletters, emails, social media etc. 

Teach new beekeepers how to monitor for mites in August.

Help your members prepare their monitoring materials.

Support your members in making sure they are able to monitor mites effectively and report their data.

DATA COLLECTION: Varroa monitoring data will be uploaded to  

CONTACT: or 415 362-1137

Get resources and stay up to date at!

Thank you,

The Mite-A-Thon Partners

A New Organic Acid Varroa Mite Medication

CATCH THE BUZZ    October 15, 2016

At its October meeting, the Committee for Medicinal Products for Veterinary Use (CVMP) of the European Medicines Agency (EMA) recommended the granting of a marketing authorization in the European Union (EU) for VarroMed (oxalic acid dihydrate / formic acid). This antiparasitic medicine treats the Varroa mite infestation in honey-bee colonies, which is considered to be the most significant parasitic health concern affecting honey bees worldwide.

Honey bees are essential for pollination of crops and wild plants in Europe. The European Commission estimates that pollinators, including honey bees, bumble bees and wild bees, contribute at least 22 billion euros each year to European agriculture and pollinate over 80% of crops and wild plants on the continent.

However, beekeepers around the world have reported losses of honey-bee colonies, which are considered to be caused by a combination of different factors such as habitat loss, climate change, pesticide use, and also diseases affecting bee health. A continued decline of these pollinators could lead to serious biological, agricultural, environmental and economic difficulties.

The main parasite affecting honey bees is the Varroa mite (Varroa destructor), an invasive species from Asia that has affected bee colonies worldwide. The Varroa mite feeds on the circulatory fluid of bees and brood (bee larvae) and can also contribute to the spread of viruses and bacteria.

VarroMed is intended to kill Varroa mites and is a liquid which is trickled onto bees in the hive. It contains as active substance a fixed combination of two organic acids, oxalic acid dihydrate and formic acid. Both substances have been known in veterinary medicine for a long time and are either naturally present in foods or accepted for use in foods. The medicine is not expected to pose a risk to human or animal health or the environment, if used according to the product information.

VarroMed is intended to be used as part of an integrated Varroa control programme, which includes not only treatment with medicines but also non-chemical techniques like queen trapping or drone brood removal. It can be used either as a single-dose treatment during the broodless period (winter treatment) or in the presence of brood (spring or autumn), which will usually require repeated treatments.

Treatment should only be given at times when honey is not produced by bees.

The effectiveness and safety of the product in the protection of honey bees against Varroa mites was tested in laboratory and field studies in different European climate conditions. VarroMed was effective in killing more than 80% of mites, which is below the effectiveness level of 90% recommended by the CVMP Varroa guideline. However, CVMP agreed that a lower level of 80% could be accepted when integrated Varroa control techniques are put in place. Repeated treatment of VarroMed might also result in increased bee mortality, and careful dosing is recommended to avoid overdosing.

The medicine has been classified as MUMS (minor use minor species/limited market), and, therefore, reduced data requirements apply, and these have been considered in the assessment. EMA’s MUMS policy aims to stimulate the development of new veterinary medicines for minor species and for diseases in major species for which the market is limited and that would otherwise not be developed under current market conditions.

The CVMP opinion will now be sent to the European Commission for the adoption of a decision on an EU-wide marketing authorization.

Approaches and Challenges to Managing Nosema and Honey Bee Colonies

Cornell University  Entomology Today  August 8, 2016

It’s a tough time to be a pollinator.

Bee, butterfly, and bat populations are in decline across the globe. Even the honey bee, perhaps the best-studied pollinator, has suffered great losses as beekeepers and researchers struggle to identify the causes. In recent years, it’s become clear that no one factor is responsible — honey bees face an onslaught of pressures, ranging from pesticides to viruses to parasites.

A recent Journal of Economy Entomology paper puts a spotlight on just one of these problems, the honey bee pest Nosema. Summarizing decades of intensive research from across the globe, two University of Minnesota and Pennsylvania State University entomologists outline precisely why Nosemarepresents an intractable problem for beekeepers. Their sobering conclusion — that far more research and resources are still needed to equip beekeepers with the right tools for managing Nosema infections — throws into relief the challenge of understanding and reversing global declines not just in honey bees, but in many other pollinators as well.

Nosema species, two of which are known to infect honey bees, belong to a group of fungi known as microsporidians. These fungal parasites live out their days within the cells of a host animal, which, in the case of N. apis and N. ceranae, is the digestive tract of honey bees. Perhaps as a result of this lifestyle, microsporidians such as Nosema evolved stripped-down versions of mitochondria. Unable to manufacture enough energy themselves, Nosema relies instead upon the energy produced by its honey bee host’s cells, with sometimes-grave consequences for the host.

(Image: Nosema spores (red arrows) in a sample with pollen and tissue debris.)

Anchored in the midgut and munching on its host’s energy molecules,Nosema can effectively “starve” infected honeybees. This can accelerate a bee’s normal development, causing worker bees to mature earlier into foragers — but poor ones at that. Nosema-infected bees take longer rests, are less efficient at gathering pollen and nectar, and are more likely to become disoriented than their uninfected counterparts. The parasite spreads when spores leave the digestive tract. When enough of a colony’s inhabitants are infected, the colony suffers or even collapses. 

So what’s a beekeeper to do? The first obstacle is to determine whether a colony is, in fact, suffering from a Nosema infection.

“One of the major challenges of diagnosing Nosema is that there are no 100 percent reliable clinical symptoms,” said lead author Holly Holt. “Without a microscope or molecular tools, it’s impossible to visually inspect a colony with the naked eye and know with certainty whetherNosema of either species is present.”

Laboratory testing is currently the only foolproof method for diagnosing the parasite, which can be time- and resource-prohibitive for many beekeepers. (However, beekeepers in the United States and Canada can benefit from free testing provided by the USDA.)

Several promising methods of diagnosis are on the horizon, including a pregnancy test-like dipstick that confirms the presence of Nosema, but none are widely tested and available yet.

More challenges await the beekeeper that does overcome the hurdle of diagnosis. There’s a desperate need, Holt and co-author Christina Grozinger stress, for guidelines and best practices as to when a beekeeper should intervene and treat Nosema. After all, not everyNosema infection results in colony collapse. Some don’t even require treatment.

That’s because Nosema species have shown a patchwork of prevalence and virulence in honey bees. Of the two Nosema species that parasitize European honey bees, N. apis has been familiar to beekeepers since the early twentieth century, and N. ceranae represents a newer, potentially more competitive and concerning threat. Studies have shown the species to have wildly different impacts on honey bees in different locations.

Variations in climate, honey bee resilience, other hive stressors, andNosema strains all play a role in determining whether the parasite will prove undetectable or a death sentence for a hive. In other words, beekeepers need localized guidelines.

When Nosema does begin to choke a hive, beekeepers have few treatment options from which to choose. Fumagillin is the only widely used chemical treatment for Nosema, but its toxicity in humans resulted in a European Union ban on the chemical. More recent research has shown that fumagillin may not be so great for bees, either; over the long-term, it may even exacerbate the problem it’s meant to treat.

Other treatments for Nosema, including anti-fungal molecules, essential oils, and good, old-fashioned equipment sterilization, have not yet been studied enough to be widely implemented.

A one-size-fits-all approach to treating Nosema, the paper argues, will never work for global honey bee populations. It’s a portrait in miniature of the wider challenges and knowledge gaps that beekeepers face.

“Researchers have a lot to do to support beekeepers,” wrote Holt, who is the science coordinator for the Monarch Joint Venture. “The good news is that there’s a huge amount of cross-disciplinary and cross-organization effort going into pollinator conservation. However, positive change will not come about without policy changes based on scientific findings and continued support of research that seeks to investigate and mitigate pollinator stressors.”

Read more at:

Approaches and Challenges to Managing Nosema (Microspora: Nosematidae) Parasites in Honey Bee (Hymenoptera: Apidae) Colonies