Emerging Tick Borne Diseases Seminar 29 November 2006, University of Salford.

THE CHARTERED INSTITUTE OF ENVIRONMENTAL HEALTH
TICK BORNE DISEASES, THE PRECAUTIONARY PRINCIPLE

Summary of this Seminar, reported for Lyme Disease Action
by Dewi Bermingham
(Author’s comments in italic)

It should be borne in mind that I am not an independent and neutral observer. My wife became ill some years ago, and until she abandoned the NHS for an independent doctor, she continued to deteriorate. Two years on, she is now near to fully recovered. This was achieved by long term, high dose antibiotic therapy.

Dewi Bermingham 6th December ’06.


The first speaker was Mr Xavier Bonnefoy, former head of Health and Housing at the WHO’s European Regional Office.

Mr Bonnefoy discussed how the changes in the way we live today have led to an increase in the chances of people receiving a tick bite. This increase is caused by a number of factors including urban sprawl, second homes in the country, outdoor pursuits, country gardens, and urbanisation of wild animals.

Mr Bonnefoy introduced many interesting facts and figures regarding ticks and tick-borne disease. For example, he stated that 13% of Lyme disease cases involve arthritic symptoms, 4% neurological complications, and 1% cause cardiac problems. Of the 10,000 cases of Tick-Borne Encephalitis across Europe in 1997, 1% proved fatal. Also, in some parts of Austria there are 130 cases of Tick-borne disease per 100,000 population.

The second speaker was Professor Sarah Randolph, Professor of Parasite Ecology at Oxford University. This was a particularly interesting talk in which she showed how models of the distribution of ticks and tick-borne diseases are produced and then used to predict the occurrence of ticks and the diseases. The model is checked by seeing how well it predicts actual measurements. Where the model predicts ticks and the diseases in an area with no record of ticks then this is called a ‘false positive.’ Unlike a ‘false positive’ test result that would be considered ‘wrong’ in a medical test, this type of ‘false positive’ is investigated to see whether the model is wrong or whether the model is actually right but the ticks and their diseases have simply not been found or reported.

Professor Randolph went on to discuss how factors such as seasonal variation, humidity, and fauna affect the chances of ticks being able to carry and transmit diseases. Professor Randolph brought up the point of when the ticks were able to transmit Borrelia and TBE. The nymph stage and the larva stage of the tick population must feed on the same host within the time that that host was able to transmit the bacteria/virus. To do this the periods of nymph and larva growth cycles had to overlap. If this did not occur then it was not possible for the Borrelia to be passed from one to the other. These growth cycles depend on the temperature and humidity pattern during the year.

The general consensus of Professor Randolph and many of the audience was that the large rise in deer populations was the main factor in the increase in incidence of Lyme borreliosis and TBE – as opposed to climate change. The reason for this was not that the deer transmitted the disease, but that the deer were an excellent food source for the adult tick.

Professor Randolph’s model covered distribution and hot spots across Europe as well as Britain.

The third speaker was Dr Sue O’Connell, of the Health Protection Agency (HPA).

Dr. O’Connell made the points that the diagnosis of Lyme disease is a clinical one. The tests that her laboratory does should be used to help with the diagnosis. The tests, as done by her laboratory, are ‘well characterised.’ Dr. O’Connell also made the point that there is a lot of inappropriate testing being done, which she believed, should be discouraged. There were other laboratories offering different types of test that produced lots of false positives. These labs are located in Florida and California.

(Taken together, I interpret this to mean that all forms of Lyme disease testing are unreliable including those of the HPA.)

Dr O’Connell went on to say that there had been over $75m spent on Lyme disease research over the last 20 years and, as a result, the disease was extremely well understood. She also strongly recommended a recent 45-page publication as the best description of Lyme disease and its treatment. Although she did not give any definite estimate of the incidence of Lyme disease in the UK she did say that it was more than a previous estimate of 0.3 per 100,000 population.

( I took it that the publication referred to was the latest IDSA guidelines).

Dr O’Connell stated that if a tick is removed within 24/36 hours of attaching itself to your body then the chance on infection is minimal.

Dr O’Connell discussed, with input from Professor Randolph, the ‘North Wales Hole.’ This is the apparent lack of Lyme cases in the Mid to North Wales area, which is counter to the predictions of Professor Randolph’s models.

Dr O’Connell also cast doubt on much of the Lyme information on the Internet. She condemned alternative treatment strategies as dangerous and she felt organisations such as ILADS were unscientific. The dangerous strategies she mentioned include Bismuth, Hyperbaric oxygen and treatment with malaria parasites. She also condemned the use of microscopical diagnosis.

(Just for the record, an independent UK doctor who diagnosed my wife clinically and who also does look at patient’s blood under the microscope, gave my wife her life back!)

Dr O’Connell produced a handout summing up the HPA’s position on Tick-borne disease.

The first speaker for the afternoon was Professor Moray Anderson of Killgerm Chemicals. Mr Anderson discussed the various ways in which the problem of ticks could be addressed. Briefly, there are four main ways in which ticks could potentially be controlled. These are: Insecticides, Modification of habitat, Biological controls, and Repellents. Three of these are clearly self-explanatory. However, biological control needs a little more explaining. Biological control can potentially involve the control of host numbers, the introduction of animals that may eat ticks, the use of some form of a ‘biological weapon’ such as fungi, or the treating of the host animals with insecticides.

The second of the afternoon’s speakers was Mr Alec Harmer, former Senior Environmental Health Officer at the New Forest District Council. Mr Harmer gave a very detailed and interesting history of how the New Forest Forestry Commission and the local Council had so successfully publicised the dangers of Lyme disease in the New Forest area. It is unfortunate that this success may have contributed to the widely-held belief, among doctors, that Lyme disease only exists in the New Forest.

Erica and Mike Gregory gave the next presentation. You will probably know that Mike was a highly successful Rugby League player and coach who, following a tick bite, became very ill and is now confined to a wheelchair and is unable to speak. Their video presentation was extremely moving. Some of the audience clearly found it hard to reconcile this disturbing presentation with Dr O’Connell’s relatively undisturbing discussion of the effects and treatment of late Lyme, which appeared to be 28 days worth of antibiotics and rest. This ‘disconnect’ was further reinforced by the presence of Wendy Fox of BADA (Borreliosis and Associated Diseases Awareness), who is herself wheelchair bound.

In conclusion, this conference was very informative and it was clear that the audience included many able people who would take away and use much of the excellent information presented. It was clear that Tick-borne disease was an important issue that would, for various reasons, become more common and must not be ignored.

Dewi Bermingham 6th December ’06.

Lyme Disease Action sponsored Mr Dewi Bermingham to attend this conference.