Another Honeybee Epidemic?

We have not learnt from the pandemic. The recent news about honeybee eradication in New South Wales (NSW), Australia, demonstrates we have learnt little from our experiences. Whether Ebola, SARS, COVID19, or in this instance, the deformed wing virus (DWV), the knee jerk reaction to the discovery of an infectious organism is understandable, but unfortunately very unlikely to work. Varroa mite, or its more sinister synonym, varroa destructor, was recently first discovered in Australian honeybee populations. Varroa is a honeybee parasite which attaches onto, and subsequently reproduces in bee brood. They are in themselves not a major problem, except they often also carry the deformed wing virus (DWV). Larvae and young bees infected with DWV develop abnormal wings which are ineffective for flight, resulting in the inability to forage and the ultimate demise of the colony. But that’s not all. Since varroa can jump between bees, DWV can thus be transmitted from colony to colony, resulting in an epidemic.

Major international news outlets caught on to the announcement in NSW over the last week. In the UK, both the British Broadcasting Corporation (BBC) and the Guardian have already reported on it (1, 2). They estimate that up to 600 honeybee colonies will be euthanised within a 10km geographical area, and a strict lockdown order has been put into place including a 25km surveillance zone. Sound familiar? Australia, which has hitherto been viewed as an exemplar throughout the COVID19 pandemic, seems to now be employing the same strategies to deal with this new pathogen that has reached its shores. On the surface, it does seem sensible: eradicate majority of hosts and impose lockdown measures, and the virus can be defeated. Yet, there are deeper issues to explore and lessons to learn from the similar handling of other infectious outbreaks, as well as unintended consequences to examine as a result.

Varroa

Tom Seeley, a USA-based professor specialising in honeybees, has spent many years tracing the evolution, spread and effects of varroa. He first lamented what seemed like the inevitable extinction of the honeybee population in USA and Europe in the 1990s, when varroa made the jump from Asian honeybees to Europe and then spread throughout the globe (3). Mortality rates of colonies were unacceptably high, and many commercial beekeeping operations struggled to maintain financial viability. Their colonies were decimated by DWV, and the honeybee pandemic prompted the very public rhetoric around possible extinction of the honeybee, and the importance of preserving the population of honeybees (and other pollinators). It took time for these observations to make it to international media, and by that time, Seeley and other entomologists had already noticed an increase in honeybee populations. Contrary to his earlier predictions, not all colonies were wiped out by varroa and DWV. He noted the repopulation of wild colonies in the Arnot Forest. He studied them to discover hygienic behaviour and resistance traits of the survivors. He then went on to note that bees were not simply genetically “immune” to varroa or DWV, but rather possessed a whole multitude of factors which protected them against severe losses. These observations continued to result in a flourish of other related research from many universities and organisations around the world.

As an intensive care doctor, I have witnessed the devastation of the COVID19 pandemic. As a researcher in healthcare resilience, I possess an understanding of the multitude of factors contributing to complex adaptive systems. As a beekeeper, I know both the dilemmas on the mind of fellow apiarists in NSW and have examined the evidence and history around varroa with my scientific and medical background.

The NSW department of agriculture announced its plans in June 2022. Along with the 10km eradication zone and the 25km surveillance zone, a 50km biosecurity zone will be set up, which requires beekeepers to notify the department of primary industries of the location of their hives (2). Theoretically, this could work. It contains several layers of protection, from eradicating existing infected colonies, through increasing inspections, to gathering baseline data from a wider geographical area. However, there are several issues with these approaches.

An assumption of closed systems

Firstly, it assumes a closed system centred around managed colonies. Even if up to 90% of honeybee colonies are managed, the 10% of wild colonies are not accounted for. They may themselves contain varroa which can then act as reservoirs. These may spread and the officials will always be playing catch-up. The “lockdown” approach has not worked for the rest of the world for COVID19, and even Australia, which was initially successful, could not maintain their isolationist approach and saw additional COVID19 waves in 2022 (4). Likewise, honeybees do not exist in isolation, and cannot be fully confined to geographical areas. Nevertheless, honeybee “lockdown” is not all bad. A major contributor to the effectiveness of varroa transmission is the practice of relocating hives for pollination services. This has been done for many years in California for almond orchards, as well as in Australia. But the artificial dramatic increase in density of honeybees and colonies makes transmission of diseases very easy. A Californian beekeeper has likened it to “sending the bees to war” (5). A honeybee lockdown will indeed minimise the transmission of varroa during large-scale pollination services and continues to highlight the consequences of this very unphysiological practice. But even the eradication approach assumes that all hives are eradicated at the same time, with all the honeybees contained within the hives. This is near impossible. Coordination will be a logistical nightmare. Straggler bees in the environment may find their way into other hives and if they are affected by varroa, will then infect other hives. The subsequent disposal of dead bees, and their honey and wax stores, must be done in a timely fashion to prevent robbing from other honeybees and insects, which poses an additional risk for varroa spread. Granted, 10km is not all that wide an area to coordinate and eradicate. There is a chance that it could work, but it nevertheless assumes many uncontrollable factors.

Similarly, the “lockdown” of bees is also incredibly difficult to enforce, and likely to result in unintended consequences. There was a story told by global health professor Hans Rosling (6). He was advising local government in a low-middle income country that was suffering with what seemed like a new and unidentified pathogen. When he made the decision to close roads and isolate the area, he did so to prevent transmission. What actually happened was that families, unable to get to the markets to sell their goods and earn their living, resorted to unsafe water travel, in boats not suited for the purpose. Many women and children died in those boats, overcrowded, and overloaded, at the mercy of seamen keen to earn a quick buck. He could not have foreseen these consequences, and neither can we of the NSW honeybee lockdown. But to think that such an enforced lockdown will have no consequences is naive at best.

Treating heavily for varroa in an acute setting makes some sense. This is what occurs in acute medicine and intensive care. Decompensation because of infection is treated with antibiotics, and indeed the advent of antibiotics has saved innumerable lives. But the issue is that many beekeeping associations have already advocated for prophylactic treatment for many years since the rise of varroa, and have seen many consequences, both expected and unintended. The British Beekeeping Association (BBKA) recommends regular treatment against varroa (7). On the surface this sounds logical, but treatments such as oxalic acid vapours are known to be harmful for bees too. Moreover, it reduces natural selection pressure, makes bees reliant on such treatments, and accelerates resistance in varroa, just like it does for humans and antibiotics. In addition, some beekeepers do not adhere to prescribed treatment dosages and timings. The result is further toxicity, weaker bees, stronger varroa and increased transmission of diseases.

In his book Treatment-Free Beekeeping, David Heaf reviews some of the problems with varroa treatments, and more importantly, highlights the lack of benefit based on equivalent colony mortality rates between treatment-free and treated colonies nationally in the UK (8). There is sufficient evidence that a combination of survivor genetics, epigenetic factors and hygienic behaviour have resulted in many honeybee colonies around the world “tolerating” the presence of varroa, rather than eradicating it. This is likely the realistic endpoint of this saga. It is like that of other human pandemics like COVID19 and influenza.

Compliance and availability of data

The second problem with the NSW approach is that it assumes responsible voluntary reporting from beekeepers. Since the public rhetoric around varroa several years ago, the number of “backyard” and amateur beekeepers have dramatically increased. Assuming that all these beekeepers will voluntarily divulge information about their hives, particularly considering the threat of invasive inspections and potential eradication, is utopian. In addition, some hive designs do not lend themselves well to traditional forms of inspection, or to any inspection at all. These include any of the unframed hives such as Warré, tree-hives and their modifications, and colonies living in cavities such as walls of buildings. As a result, any of these hives can again become reservoirs of varroa. But this is not the say that they are in anyway inferior to the standard hive designs such as National and Langstroth. Insulated and unframed hives aim to mimic the natural environment of wild honeybee colonies within tree-cavities. It acknowledges that while we understand much of bee biology, we are still unable to factor for all the complexities within a colony, and thus brings us to the third point of why the NSW approach is unlikely to succeed.

Wider determinants of honeybee health

This point is probably most important: the approach fails to address underlying social and environmental determinants of honeybee health. It does not challenge the established human demand for honey and pollination services which are already detrimental to bees. The high density of honeybee colonies, particularly in some cities, has already negatively impacted the population of other flying pollinators such as solitary bees and wasps. The global demand for honey which supports the industry encourages human-centred practices which do a disservice to the labour of the honeybees. These may include heavy feeding, over-harvesting, and encouraging unnaturally large colonies to maximise efficiency. The capitalist forces which promote heavy mono-agriculture reliant on intense pollination fail to respectfully steward our insect workers. Such operations cause disorientation, uniform forage, and intense competition. All are detrimental to honeybees. The continued allegiance of beekeeping associations to traditional hive designs, invasive inspection regimes and treatments with narrow therapeutic indices speak of our collective wilful ignorance of scientific evidence and progress. They ignore recent understanding of the importance of thermoregulation, natural comb spatial distribution, and minimising disturbances to the colony, amongst others. 

The Australian response to COVID19 was deemed successful, but this was only delayed till February 2022, when they had a spike in both cases and deaths (4). With the world being so interconnected, it was unlikely that an eradicate, isolate and clamp-down approach would be successful in controlling a virulent pathogen. Likewise, for varroa and DWV. The NSW department of primary industries has been faced with an impossible task to control the new pathogen. They are taking probably the most logical approach but are unlikely to completely prevent the transmission of varroa and DWV. So what strategies are available going forward to build a more resilient apiculture industry? After this acute event has passed, multi-level approaches to address slow variables are key to learning and improvement.

Multi-level approaches to true resilience

On the honeybee level, we must support their natural instincts and resilience. This means allowing natural rhythms and supporting the development of hygienic behaviour and resistance traits. Swarming provides a natural brood-break and therefore disrupts the reproductive cycle of varroa (8). Yet, many beekeeping associations, including the British Beekeeping Association, advocate for swarm-prevention measures (7). Some may seem benign such as making artificial splits or reducing number of queen cells, while others such as clipping the wings of queens, or the use of queen excluders are more interventional and arguably unethical. But none are harmless. Artificial splits don’t allow for brood-break and may continue to transmit diseases, particularly if the split is only done to another beehive mere metres away. Cutting queen cells such that only one remains facilitates splitting but may inadvertently reduce the natural selection pressure artificially. Normally several queens will be raised, and success is determined probably not just based on which emerges first and kills the other potential queens, but also on other genetic and epigenetic factors which determine the speed of development and emergence, as well as the vigour and viability of said queen. Cutting takes matters into the hands of humans who still do not fully understand all the processes. There is a reason why “redundancy” is a key factor conferring resilience, particularly when it comes to socio-ecological systems (9). Allowing for swarms and natural queen production prevents varroa from thriving. It may not eradicate, but then again, when has forced prevention of reproduction ever worked in complex societies?

News and media outlets have already raised public awareness of the plight of honeybees and other pollinators. Much good has resulted including increased planting for pollinators, number of registered beekeepers and nesting cavities. But there is more that regional and national beekeeping associations and societies can do. A more pluralistic approach helps to promote diversity – a key factor for resilience of socio-ecological systems (9). This may include acceptance of various philosophies of beekeeping and a wider range of hive designs. Accordingly, smaller scale and low-intervention beekeeping allows for a wider and more equitable distribution of honeybee colonies. More people can participate. Smaller apiaries exert minimal micro-ecological impact compared to larger-scale commercial operations. Simpler and more localised distribution channels reduce the carbon footprint of otherwise global shipping. And with regards to the current situation, a less dense and more diffuse beekeeping landscape reduces the spread of diseases. To this end, re-evaluation of treatment recommendations by associations and organisations must also consider the dynamicity of natural selection and development of resistant traits, both for bees against varroa, and varroa against treatments.

On a societal level, there is a need to reduce the demand and consumption of honey internationally. Honey is a precious resource for honeybees, and we must steward it responsibly. Israeli start-up Bee-io has adopted an interesting approach. By mixing nectar with synthetic enzymes in laboratories, honey is produced without the reliance on bees. However, the product still lacks many of the constituents present in natural honey, and uses only a limited range of nectar sources, compared to natural honey. It thus may act as an adequate, if not complete, replacement. Also, their business model continues to rely on capitalist forces which invariably prioritises profit. Perhaps more conducive is the Living Standards Framework adopted by New Zealand, which reframes “capitals” to include not just financial capital, but also social and environmental capital (10). This asserts explicit value to the immeasurable relationships between humans, our environments, and the flora and fauna we depend on for our continued survival. Such high-level priority-setting which considers ecological concerns as equal to human desires may then drive the overall trajectory of humankind towards a more sustainable equilibrium with the other species sharing our environment.

The bees will recover from varroa, just like they have in the rest of the world. Eradication, isolation, and surveillance may result in a temporary fix, but are unlikely to completely prevent varroa from persisting on the Australian continent. What the event has raised though, is the wider need to question the traditional methods we have for infection prevention and control, challenge the status quo of human demand for honey, and provide the opportunity to address the many slow variables which can ultimately result in a more sustainable and distributed apiculture industry.

References

1.         May N. New eradication zone established and 600 hives destroyed as NSW bee industry battles varroa mite: The Guardian; 2022 [Available from: https://www.theguardian.com/environment/2022/jun/30/bee-industry-confident-varroa-mite-can-be-contained-after-600-hives-destroyed-in-nsw.

2.         Turnbull T. Australia honey bees put in lockdown due to deadly varroa parasite Online: British Broadcasting Corporation; 2022 [Available from: https://www.bbc.co.uk/news/world-australia-61976446.

3.         Seeley TD. The Lives of Bees: The Untold Story of the Honey Bee in the Wild: Princeton University Press; 2019.

4.         Ritchie H, Mathieu E, Rodés-Guirao L, Appel C, Giattino C, Ortiz-Ospina E, et al. Coronavirus Pandemic (COVID-19): Our World in Data; 2022 [Available from: https://ourworldindata.org/coronavirus.

5.         McGivney A. ‘Like sending bees to war’: the deadly truth behind your almond milk obsession Online: The Guardian; 2020 [Available from: https://www.theguardian.com/environment/2020/jan/07/honeybees-deaths-almonds-hives-aoe.

6.         Rosling H. Factfulness. London: Hodder & Stoughton Ltd; 2018.

7.         Davis I, Cullum-Kenyon R. The BBKA Guide to Beekeeping, Second Edition: Bloomsbury Publishing; 2016.

8.         Heaf D. Treatment Free Beekeeping: IBRA & NBB; 2021.

9.         Biggs R, Schlüter M, Schoon ML. Principles for Building Resilience: Cambridge University Press; 2015.

10.       Campbell-Macdonald G. Living Standards Framework: New Zealand Treasury; 2018 [Available from: https://www.wgtn.ac.nz/__data/assets/pdf_file/0007/1780954/Grace-Campbell-Macdonald-Living-Standards-Framework.pdf.