A Lyme disease vaccine is finally close: what it means for stalkers

One remarkable aspect of the Covid-19 pandemic was the blistering speed of vaccine development. Driven by global urgency, capital investment flowed into research without constraint, proving that humanity can achieve extraordinary things when financial barriers are removed.

Sadly, the same enthusiasm has not been extended to Lyme disease, a persistent illness that has affected the British countryside for decades. While the medical world moved mountains overnight to tackle a global crisis, rural communities have largely been left to manage tick-borne diseases independently, relying primarily on basic defensive clothing and personal vigilance out in the field.

Why a Lyme disease vaccine has taken so long

Fortunately, public awareness has grown. A few high-profile figures contracting the illness has elevated the conversation, capturing public attention in a way that standard statistics rarely do. Historically, progress has been slow. The early LYMErix vaccine was withdrawn in 2002, not for want of effectiveness but because poor demand and unfounded safety fears made it commercially unviable.

Pharmaceutical companies long viewed Lyme as a niche market, preferring to pour resources into major global health issues like heart disease and obesity. Yet the numbers are sobering. Lyme is among the world’s most common vector-borne diseases, with an estimated 476,000 people diagnosed and treated in the US alone each year. Closer to home, the UK Health Security Agency recorded around 1,500 laboratory-confirmed cases in England in 2024, though because many infections are diagnosed without a test, the true figure is thought to be several times higher.

Naturally, when ticks are discussed our expanding deer population takes the blame, but scientific evidence shows that we have been misjudging our quarry. In a fascinating twist, deer are “non-competent” hosts: their blood carries a borreliacidal property that clears the Borrelia bacteria from a feeding tick’s gut.

The real reservoirs are small woodland mammals such as mice and voles, alongside ground-dwelling birds such as blackbirds and thrushes. Deer are merely the primary reproductive hosts.

A single adult female tick requires a substantial blood meal to lay her thousands of eggs. Consequently, as deer roam across estates they act as inadvertent transport, distributing ticks across the habitat and into closer contact with those managing the land.

The good news is that a proper medical shield is finally working its way through the regulatory pipeline. There are currently three major candidates progressing through clinical trials, all trying to tackle a complex bacterium that varies considerably from region to region.

The frontrunner is a traditional vaccine developed by Pfizer and Valneva, which recently demonstrated a 73% efficacy rate in advanced trials. Instead of treating the human body directly, it cleverly targets the bacteria inside the tick itself while it is feeding, neutralising the threat before the pathogen can be transmitted.

Also in development, though at an earlier stage, are two high-tech mRNA offerings from Moderna, engineered to offer broad protection across both North American and European strains.

The practical question for anyone working outdoors is exactly when we can expect a widespread rollout. With Pfizer currently preparing its data for regulatory review, industry estimates point towards availability within the next couple of years.

For the gamekeeping and stalking fraternity it cannot come soon enough. We have spent decades dealing with the tedious reality of returning from a day on the hill only to spend the evening under a bright light with a pair of fine-nosed tweezers, carefully removing tiny parasites from the most awkward and uncomfortable places.

Low-tech vigilance until the vaccine arrives

Until we can simply roll up our sleeves at the local GP surgery before the season starts, the British sporting community must continue to rely on low-tech vigilance. We will keep tucking trousers into socks and dousing ourselves in repellents, waging a quiet war against a microscopic foe with nothing but canvas and determination.

It is a uniquely British irony that while global science stands on the brink of a brilliant breakthrough, our best immediate defence remains a particularly thorough post-shoot inspection.