Dáil Éireann Debate, Thursday - 13 July 2017
913. Deputy Michael McGrath asked the Minister for Health if the HSE is following the guidelines issued by the Centre for Disease Control, CDC, in the USA for the testing for Lyme disease; if its attention has been drawn to the change in policy by the CDC whereby it now accepts the need for more than one test and that new forms of test are required; and if he will make a statement on the matter. [34655/17]
View answerLyme disease (also known as Lyme borreliosis) is an infection caused by a spiral-shaped bacterium called Borrelia burgdorferi. It is transmitted to humans by bites from ticks infected with the bacteria. The Health Protection Surveillance Centre (HPSC) of the HSE has extensive information concerning Lyme disease on its website http://www.hpsc.ie/a-z/vectorborne/lymedisease/.
Lyme disease is diagnosed by medical history and physical examination. The infection is confirmed by blood tests which look for antibodies produced by an infected person's body in response to the infection. These normally take several weeks to develop and may not be present in the early stages of the disease. The standard approach to Lyme diagnostics is a two-stage approach and involves using a sensitive enzyme immunoassay (EIA) as an initial, screening step. Screening EIAs can be insufficiently specific, giving false-positive reactions in the presence of other similar bacteria, and certain other viral infections, including glandular fever. In addition, blood samples from patients with autoimmune disorders and other inflammatory conditions can also lead to false-positive results. Samples giving positive or equivocal results in screening tests are further investigated in a second-stage immunoblot (Western blot) tests. Use of immunoblot testing greatly increases specificity. Using this two stage approach will give a great degree of certainty around the diagnosis of Lyme.
All clinical (and other) laboratories in Ireland must undergo continuous quality assurance to ensure that the quality of the diagnostics they provide is maintained at the highest international level for human diagnostics. Some laboratories abroad do not use antibody tests like the EIA (screening ELISA test) and Western Blot and instead will use other types of tests, for example, testing for levels of a specific white blood cell (CD-57) or lymphocyte transformation tests (tests to measure how specific cells in a person's immune system respond when exposed to antigens against Borrelia burgdorferi - the bacterium responsible for Lyme disease). These types of tests are not currently recommended by international groups for a number of reasons:
1. There is not enough scientific evidence that they are suitable tests to diagnose Lyme disease;
2. There is no standard method to perform and interpret these kind of tests; and
3. Positive results in these kinds of tests may be due to other illnesses or conditions and not just Borrelia infection.
The Scientific Advisory Committee of the HPSC, the Infectious Diseases Society of Ireland, the Irish Society of Clinical Microbiologists, the Irish Institute of Clinical Neuroscience and the Irish College of General Practitioners agreed a Consensus Statement on the Clinical Management of Lyme Borreliosis, which endorsed the previously referenced, internationally recognised set of guidelines (those of the IDSA) to Medical Practitioners to ensure a standardised approach to the diagnosis and management of Lyme disease in Ireland.
The Scientific Advisory Committee of the HPSC has established a Lyme Borreliosis Sub-Committee, the aim of which is to develop strategies to undertake primary prevention in order to minimise the harm caused by Lyme Borreliosis in Ireland. In addition to staff from the HPSC, the membership of the Sub-Committee includes specialists in Public Health Medicine, Consultants in Infectious Diseases, Clinical Microbiology, Occupational Health an Entomologist from the Parks and Wildlife Service, a representative from the Local Government Management Agency, an Environmental Health Officer and, very importantly, a representative from Tick Talk Ireland, the primary Support Group for Lyme disease in Ireland.
The initial work of the Lyme Borreliosis Sub-committee involved a survey of laboratory methods for the diagnosis of Lyme borreliosis in Ireland, the development of Lyme borreliosis guidance for general practitioners, the publication of medical media articles to highlight diagnostics and laboratory methods relating to Lyme borreliosis available in Ireland. Material has been produced which is aimed both at the general public and General Practitioners.
There is extensive information for the public and health professionals on the HPSC website. This information for the public includes:
- Lyme Disease Frequently Asked Questions;
- Laboratory testing for Lyme Disease: FAQs for general public;
- Lyme Disease Illustrations; and
- CDC's instructions on how to remove a tick.
There is significant support and information for health professionals on the HPSC website. These supports include a fact sheet on tick borne diseases, including Lyne Disease. This fact sheet gives information on clinical the disease, transmission routes, prevention measures, diagnosis, and management and treatment. There is also an erythema migrans (EM) diagnostic tool to aid health professionals in the diagnosis of EM, which is frequently the earliest clinical manifestation of Lyme borreliosis.
The Deputy refers to guidelines issued by the Centre for Disease Control in the USA. It would be inappropriate for me to comment on guidelines used in other countries.
