Lyme Disease

Lord Trees Excerpts

Thursday 22nd October 2015 Grand Committee

[Lord Trees (CB)]

My Lords, I too thank the noble Lord, Lord Greaves, for bringing forward this timely debate. As someone who for much of their professional life has researched and taught on tick-borne diseases, I never imagined that I would be speaking on this subject in your Lordships’ House, but I would say that my students might have preferred it had my lectures been limited to four minutes, as are today’s contributions. I may be the only person here who has actually been to Lyme. During a road trip down the eastern seaboard of the US some years ago, I dragged my wife on a detour to visit the lovely New England village of Lyme in Connecticut with white clapboard houses. It is where, in the 1970s, the first outbreak of the disease was thoroughly investigated, which led to the discovery of the causal organism and much of the characterisation of the disease. However, the first important point to appreciate is that this is not a new disease. The characteristic skin lesion was first described as far back as 1909.

Looking at the data from Public Health England, it is not clear whether there has been a big change in incidence, but there is certainly a big increase in concern. There is certainly some evidence of increased distribution and abundance of the tick vector, Ixodes ricinus, and in recent years we have seen an increase in the number of wild animal hosts, particularly deer and game birds, both of which are extremely good hosts for ticks. There is also an increase in human contact with ticks, not only in rural areas but also in peri-urban and suburban areas.

As I say, it is well known that deer are excellent hosts for the tick. Like the noble Lord, Lord Patel, I live in Perthshire and I regularly have to pick ticks off myself that I contract in the garden, which is frequently visited by deer. But—this is an important point—the ticks are almost always at the larval stage; they are tiny, pinhead-sized larvae which do not transmit Lyme disease. It is during the larger nymphal and adult stages when the disease is transmitted, and these ticks are much less abundant than the larvae.

There are risks, but I would like to make the point that it would be a tragedy if people were dissuaded from enjoying the great benefits of the outdoors for fear of Lyme disease. Having said that, there is no doubt that it is a severe and debilitating disease if it is not diagnosed and treated early. In the absence of a vaccine for humans, I suggest that the key to controlling it, as has been said by a number of noble Lords, is to ensure that GPs are aware of the threat and are thus able to instigate early diagnosis and treatment.

It is a fact that in western medicine GP training in zoonotic infections and parasitic diseases is very limited. That is for understandable reasons, and I am fully aware of the pressures on curriculum time in our undergraduate medical courses. None the less, what are the Government doing to encourage awareness among GPs of tick-borne infections? This is of course a matter for continuing professional development but there is also a role for the state, which bears the costs of undiagnosed and misdiagnosed cases that lead to severe and chronic disease.

Lyme disease is a good example of the “one health” concept, which recognises the connectivity between human and animal health, and indeed plant and environmental health. It is a concept embraced well by vets but, I suggest, is understood much less by our hard-pressed GPs. Pathogens do not recognise differences between humans and animals. With regard to zoonotic infections, those infections specifically transmitted between animals and humans and vice versa, such as the agent of Lyme disease, we need to ensure that our GPs are adequately aware of the hazards. That way we can prevent serious illness in people and reduce burdens on the hard-pressed NHS.