The announcement that Bovilis® Huskvac, the UK’s only licensed lungworm vaccine, will be withdrawn from the market from 2027 comes at precisely the wrong moment for UK cattle farming.
Cattle vet and COWS member Rob Howe has written to the editor of the Veterinary Record to air the industry's concerns.
Resistance
We now know that anthelmintic resistance in cattle lungworm is here. In 2024, Campbell and colleagues published evidence of macrocyclic lactone (ivermectin and moxidectin) inefficacy against Dictyocaulus viviparus in UK dairy calves, describing findings highly suggestive of macrocyclic lactone resistance. The same report highlighted the severe and unpredictable nature of clinical lungworm outbreaks and the absence of established field guidelines for diagnosing resistant lungworm. [1]
At the same time, evidence is building that resistance is not confined to lungworm. Cattle farmers have only three broad-spectrum anthelmintic families available: benzimidazoles, levamisole and macrocyclic lactones. Recent Irish research found widespread resistance among gastrointestinal nematodes on dairy calf-to-beef farms, including ivermectin resistance on all 16 farms where it was evaluated and moxidectin resistance on 8 of 11 farms. [2] Against this backdrop, the loss of a vaccine that helps reduce reliance on, and preserve the effectiveness of, our limited parasiticide arsenal is deeply concerning. Experience elsewhere demonstrates how quickly control options can be eroded once resistance becomes established. In several grazing livestock systems worldwide, multidrug-resistant gastrointestinal nematodes are already threatening economic sustainability. [2,4,8]
Risking industry progress: Integrated Parasite Management (IPM) and Targeted Selective Treatment (TST)
This announcement also coincides with growing adoption of Integrated Parasite Management (IPM). The livestock sector has made significant progress in recent years towards responsible parasiticide use, whole-farm parasite planning and environmental stewardship. Professional guidance and commentary describe IPM as a shift towards testing before treating, use of vaccination and other non-chemical prevention strategies; planned grazing, refugia-based control and environmental stewardship. [5–7]. For many farms, Huskvac has been a cornerstone of that approach.
Integrated Parasite Management is no longer a fringe concept but is becoming central to progressive veterinary advice and sustainable livestock farming. The recently launched BCVA & Control Of Worms Sustainably (COWS) IPM CPD programme reflects that shift and recognises that protecting parasiticide efficacy, animal health and ecosystem function must be considered together.
Recent commentary from Richard Wall and colleagues in Trends in Parasitology reinforces the need to integrate parasitology and ecology, preserve refugia for drug-susceptible parasite genotypes and dung-breeding fauna, and use targeted approaches to reduce unnecessary parasiticide exposure. [4] This aligns with the IPM CPD programme, developed in response to growing demand for practical, evidence-based approaches that reduce parasiticide use while maintaining animal health, welfare and productivity. Unlike gastrointestinal nematodes, which can be monitored using tools such as faecal egg counts, lungworm remains uniquely difficult to manage. Disease can emerge rapidly, often with severe consequences for animal health, welfare and productivity, while opportunities to detect infection before clinical disease develops remain limited.
Bovilis® Huskvac is used for active immunisation of cattle to reduce clinical signs and lesions of parasitic bronchitis caused by Dictyocaulus viviparus. [3]
In practice, the availability of Huskvac has enabled veterinary surgeons and farmers to implement more sustainable whole-farm parasite control plans [18,19, 20] Experience from farms adopting IPM consistently suggests that, where lungworm risk can be controlled effectively, non-chemical options for sustainable management of gutworms becomes far more achievable through pasture rotation, faecal egg count monitoring, immunity development and targeted treatment. As recently noted by Professor Eric Morgan (personal communication), the loss of Huskvac is likely to reduce the options available for sustainable parasite control and could affect the safety and acceptability of TST for gastrointestinal nematodes. Remove that safety net, and many producers may understandably feel compelled to return to more precautionary and frequent parasiticide use simply to manage the risk of a disease that remains difficult to predict and monitor.
The withdrawal of Huskvac also threatens one of the central pillars of Integrated Parasite Management: Targeted Selective Treatment (TST). TST aims to treat only those animals most likely to benefit, preserving refugia, reducing medicine use and slowing the development of resistance.[8–10] Considerable effort has gone into developing and promoting TST in ruminants, including recent work by Ellis, Kelly and Forbes demonstrating its practical application in cattle systems.[11]
However, lungworm presents a unique challenge. Unlike gastrointestinal nematodes, where treatment decisions can be informed by liveweight gain, faecal egg counts, grazing history and other indicators, there is no equivalent practical early-warning system for lungworm. Published guidance acknowledges that predicting when lungworm will strike remains difficult and that waiting for clinical signs is often too late.[5]
This is particularly concerning given evidence that the epidemiology of cattle lungworm in Great Britain has already shifted, with McCarthy and van Dijk reporting a sharp overall increase in diagnostic rate from 1975 to 2014, regional changes including increased prominence in Scotland, and more winter diagnoses, at a time when climate and management change are likely to make historical patterns less reliable.
Implications beyond lungworm
A major component of modern IPM training is dung fauna ecology and the critical role played by dung beetles and other dung-dwelling organisms in livestock systems. Dung-colonising insects provide important ecosystem services and can reduce parasitic nematode larvae on pasture. [4,15] Yet parasiticide residues excreted in dung can harm non-target dung fauna, particularly following endectocide use. [4,16] There is therefore a profound irony in the potential consequences of Huskvac’s withdrawal: the more parasiticides we use, the greater the risk of reducing the activity of the dung fauna that help clear dung and the parasites within it. Reduced dung fauna activity means dung remains on pasture for longer, potentially prolonging parasite availability and reinforcing the very cycle of challenge that drives further intervention with parasiticide treatments.
At a time when the livestock sector is working to reduce reliance on parasiticides, the withdrawal of Huskvac risks pushing farms back towards greater treatment intervention.
Emerging UK field studies and milk buyer-led programmes reinforce the importance of lungworm vaccination within IPM, consistently identifying lungworm as a widespread and difficult-to-predict constraint to sustainable parasite control. [18–20]
Antimicrobial stewardship and One Health
The consequences also extend into antimicrobial stewardship and One Health. Clinical lungworm outbreaks are often complicated by secondary bacterial pneumonia, requiring antibiotic treatment to protect animal welfare and limit production losses. If the loss of vaccination leads to more clinical lungworm, it risks increasing antibiotic use directly. The recently launched UK Ruminant Antibiotic Stewardship Roadmap, co-chaired by Fiona Lovatt, Mark Jelley and BCVA President David Black, seeks to build on this progress by promoting and evidencing responsible antibiotic use across UK ruminant systems. [14] The withdrawal of Huskvac risks cutting across that agenda by increasing disease pressure and undermining prevention-led approaches. At a time when the sector is working to reduce medicine reliance through vaccination, planning and stewardship, losing a key preventive tool risks consequences for animal health, farm productivity and human health alike.
The indirect risk is equally important. Greater reliance on parasiticides may accelerate resistance in lungworm and gastrointestinal nematodes. Heavier parasite burdens, treatment failures and chronic production losses can undermine immune resilience, increase susceptibility to secondary disease and create further need for antibiotic therapy. The loss of Huskvac could therefore increase dependence on both parasiticides and antibiotics - precisely the opposite of current stewardship goals.
This matters beyond cattle health alone. Antimicrobial resistance is widely recognised as one of the most important global public health threats, and responsible antimicrobial stewardship is now a shared objective across human and veterinary medicine.[12] Any increase in disease burden that leads to greater reliance on therapeutic interventions risks undermining that progress.
The UK livestock sector has worked hard to move in the right direction. UK-VARSS 2024 reports a 57% reduction in antibiotic sales for food-producing animals since 2014, and an 84% reduction in sales of the highest-priority critically important antibiotics. It also highlights that reducing antibiotic use has been followed by reductions in AMR at a national level. [13] That progress has been achieved through voluntary collaboration between farmers, veterinary surgeons, industry and government.
The importance of maintaining momentum behind IPM extends far beyond cattle farming. Across veterinary medicine, there is growing public, political and regulatory scrutiny of the environmental impacts of medicine use, including parasiticides. The cattle sector has responded proactively by developing IPM approaches that combine diagnostics, vaccination and other preventions, grazing management, immunity and targeted treatment to reduce reliance on parasiticides, while maintaining animal health and welfare. [5–7]
The withdrawal of Huskvac risks removing one of the key tools that has enabled this transition, potentially forcing some farms back towards greater reliance on parasiticides at precisely the time when stewardship and evidence-based medicine use are becoming increasingly important.
Conclusion
We recognise that vaccine manufacture and supply involve complex scientific, regulatory and commercial considerations. However, given the strategic importance of lungworm vaccination for animal health, welfare, sustainable parasite control, biodiversity and parasiticide stewardship, every effort should be made to explore options that might maintain access to a vaccination solution for UK cattle farmers.
The withdrawal of the UK’s only licensed lungworm vaccine also exposes a wider policy gap. The Animal Health and Welfare Pathway seeks to reduce endemic disease, improve productivity, support public goods and tackle antimicrobial resistance, while the UK’s 2024–2029 AMR National Action Plan emphasises prevention, stewardship, innovation and a One Health approach across people, animals, agriculture and the environment. Losing a sole-supplier vaccine that has supported preventive lungworm control for decades therefore risks cutting across these strategic aims unless government, regulators and industry act together to explore continuity, transition or replacement options.
This is not simply the loss of a vaccine, but the loss of one of the livestock sector’s most important tools for reducing reliance on parasiticides, preserving refugia, enabling IPM, supporting biodiversity, protecting the effectiveness of both parasiticides and antimicrobials and enabling TST.
The cattle sector has shown through antimicrobial stewardship that voluntary, evidence-based approaches can deliver meaningful reductions in medicine use. IPM represents a similar opportunity for parasiticides.
The implications extend beyond parasite control alone, with potential consequences for antimicrobial stewardship, animal health, farm productivity and the wider One Health challenge of antimicrobial resistance.
At a time when resistance is emerging in lungworm, evidence of resistance is growing across cattle parasites, and antimicrobial resistance remains one of the greatest threats to global human and animal health, the withdrawal of Huskvac threatens to undermine years of progress in IPM development and medicine stewardship. The loss of lungworm vaccination risks increasing reliance on parasiticides and, through increased disease burden and secondary bacterial complications, may also increase demand for antimicrobials. This runs counter to the principles of Integrated Parasite Management, the UK Ruminant Antibiotic Stewardship Roadmap, and the wider One Health effort to preserve the effectiveness of medicines for future generations.
We therefore urge DEFRA, VMD and APHA, working alongside industry bodies including BCVA, COWS, RUMA and other stakeholders, to convene an urgent roundtable to examine whether continuity of lungworm vaccination can be maintained, whether an alternative producer or replacement pathway is feasible, and what transition support may be required for farms currently dependent on vaccination within IPM-based parasite control plans.
The withdrawal of Huskvac should also prompt wider consideration of how the UK safeguards access to strategically important veterinary medicines when a sole supplier exits the market. Without mechanisms to support continuity, transition or replacement, other niche products critical to animal health, welfare and sustainable farming could face similar risks in future.
Jointly signed by COWS, BVA, BCVA, RUMA, Moredun Research Institute and others
References
1. Campbell P, Devine K, Forbes A, O’Neill K, McIntyre J, Bartoschek T, Laing R, Ellis K. Inefficacy of ivermectin and moxidectin treatments against Dictyocaulus viviparus in dairy calves. Veterinary Record. 2024;195(3):e4265. doi:10.1002/vetr.4265.
2. Kelleher AC, Good B, de Waal T, Keane OM. Anthelmintic resistance among gastrointestinal nematodes of cattle on dairy calf-to-beef farms in Ireland. Irish Veterinary Journal. 2020;73:12. doi:10.1186/s13620-020-00167-x.
3. Bovilis® Huskvac product information / NOAH Compendium / MSD Animal Health product summary.
4. Wall R, Morgan E, Timothy S, Sabatini G. Managing the environmental impact of livestock endectocides through refugia-based control. Trends in Parasitology. 2026. doi:10.1016/j.pt.2026.04.004.
5. Gregson S. Sustainable parasite control in cattle: integrated parasite management. Veterinary Practice InFocus. Published 6 June 2024.
6. Hewitt S, Howe R. Integrated parasite management for cattle. Vet Times. Published 10 September 2024.
7. Howe R. Parasite control in cattle is evolving. UK Vet Livestock. Published 2 September 2023.
8. Charlier J, Morgan ER, Rinaldi L, et al. Practices to optimise gastrointestinal nematode control on sheep, goat and cattle farms in Europe using targeted selective treatments. Veterinary Record. 2014;175:250–255.
9. Höglund J, et al. Weight gain-based targeted selective treatments of gastrointestinal nematodes in first-season grazing cattle. Veterinary Parasitology. 2013;196:358–365.
10. COMBAR Working Group 3. Targeted Selective Treatment: A Visual Guide of Internal Parasites in Small Ruminants. COST Action COMBAR CA16230, 2017–2022.
11. Ellis K, Kelly R, Forbes A. Ten Years of Targeted Selective Treatment: Reflections on Use of Targeted Selective Treatment in Organic Beef Youngstock. Proceedings of the British Cattle Veterinary Association Congress; 11 October 2025.
12. World Health Organization. Antimicrobial resistance. WHO fact sheet.
13. Veterinary Medicines Directorate. UK-VARSS 2024 Highlights.
14. RCVS Knowledge / RUMA. UK Ruminant Antibiotic Stewardship Roadmap.
15. Sands B, Wall R. Dung beetles reduce livestock gastrointestinal parasite availability on pasture. Journal of Applied Ecology. 2017;54:1180–1189.
16. Cooke AS, Morgan ER, Dungait JAJ. Modelling the impact of targeted anthelmintic treatment of cattle on dung fauna. Environmental Toxicology and Pharmacology. 2017;55:94–98.
17. Sands B, Giroux L, Bruce J, Darby H. Integrated parasite management and the pasture ecosystem: optimising outcomes for cattle, insect biodiversity, and soil health. Agriculture, Ecosystems & Environment. 2024;368:109022.
18. R. Howe, LLM Vets & Vet Partners, Longitudinal IPM case series over multiple years in NW UK vet practice (BCVA Congress 2021 - needs permissions)
19. UK milk buyers data (IPM) (requires refinement and permission)
20. Anuschka Marsmam, Dung Beetle Project, Prostock Vets, 2024 (BCVA Congress 2025)