News

SNH TO CONDUCT FURTHER BAT RESEARCH
02/10/2003
Scottish Natural Heritage today announced details of further research to understand the extent and frequency of European Bat Lyssavirus 2 (EBL2) in Scotland.

A pilot study using blood samples from live bats has found the presence of antibodies to EBL 2 in a number of bats surveyed. The presence of antibodies shows that some bats have come into contact with the disease, though none of the bats examined in Scotland during the summer was found to have live EBLV2 virus.

The study, in Scotland funded by SNH and the Scottish Executive, involved the development of new techniques not previously tested in the UK, and further work is now necessary to improve the scientific understanding of the preliminary findings and to inform the relationship between antibodies and the live virus.

Responding to the preliminary results, Professor Colin Galbraith, SNH Director of Science said:

"We recognise the understandable public concern following the death of a bat worker last year from rabies and the need to properly evaluate the extent of EBL2 in the Scottish bat population.

"Only one species, the Daubenton's bat, has been found to have antibodies to the virus. Even in this species the presence of antibodies appears to vary from roost to roost. The interpretation of the preliminary results must be treated with caution given the relatively small number of bats sampled and the fact that further field and laboratory work is required to validate the preliminary findings. We are now undertaking some further work before the bats move into hibernation, and are gearing up for further studies next Spring.

"The initial findings from this pilot study will greatly assist the further development of this work. While we have no immediate plans to kill any bat as part of the investigation we might need to consider the sampling of bat tissue if the further work suggests that such scientific sampling is required. Future work will develop and refine the accuracy of the results and develop our field and laboratory techniques.This will help us to better understand the pattern of EBL2 in Scotland."

"SNH put in place comprehensive health & safety measures for its staff immediately following the unfortunate death of David McRae in November 2002. These have been very effective and we have seen no further cases of infection."

"Advice to bat workers and the general public on how to minimise any risk remains unchanged: the public should avoid handling bats if at all possible, and anyone working with bats should be vaccinated against rabies.

We greatly value the advice and guidance which this project has had from the outset from the Bat Conservation Trust. "

Professor Bill Reilly of the Scottish Centre for Infection and Environmental Health
said

"This is important research, particularly in light of the public's earlier concerns about the possible threat of rabies infection. However the risk to the public at large from bats remains minimal. There is nothing in these preliminary findings to suggest any change to the current advice given to the public, and bat workers in particular, to suggest that this guidance needs to be altered. Anyone bitten or scratched by a bat should immediately wash the wound with soap and water and seek medical advice.

"This is the first research work of its type to take place in Scotland and complements a similar study underway in Lancashire. Given the groundbreaking nature of this work and the fact that there is no earlier evidence against which the early findings of this pilot study can be measured, further work is needed."

The results of the study, undertaken by the Central Science Laboratory and the Veterinary Laboratories Agency will be published once it and parallel work being undertaken by Defra in England has been completed and assessed by committees who advise Government on Dangerous Pathogens, and Zoonoses.


NOTES FOR EDITORS

1. There are two forms of European Bat Lyssavirus called EBL1 and EBL2. They are two of seven, closely related but genetically distinct Lyssaviruses, which cause rabies or rabies-like diseases around the world. The other five are (classical) Rabies, Lagos Bat virus, Mokola, Duvenhage and Australian Bat Lyssavirus

2. Scottish Natural Heritage (SNH) is currently managing the contract to look at bats and EBL. Representatives from the public health, animal health and environment sectors of the Scottish Executive and the Scottish Centre for Infection and Environmental Health (SCIEH) provide advice on the project. The study is jointly funded by the Scottish Executive and Scottish Natural Heritage and links with a parallel pilot study, funded by Defra, also undertaken by VLA and CSL in Lancashire using similar techniques to the Scottish study. Sampling and analysis is not yet complete but its results and those from the Scottish study will assist in the overall interpretation of results and influence future work elsewhere in the UK.

3. SNH is the Government's statutory advisor in respect of the conservation, enhancement, enjoyment, understanding and sustainable use of the natural heritage. Visit www.snh.org.uk for more details.

4. SCIEH is a division of the Common Services Agency for NHS Scotland. It is responsible for the national surveillance of communicable diseases and environmental health hazards and the provision of expert operational support on infection and environmental health to health boards and local authorities in Scotland. For more details, visit www.show.scot.nhs.uk/scieh/.

5. The Bat Conservation Trust is the leading UK organisation for the protection of bats and their habitats. It supports a network of over 90 voluntary bat groups and runs the National Bat Monitoring Programme. For more details, visit www.bats.org.uk.



The Pilot Study

7. This aims primarily to develop and test methodologies and procedures for sampling bats to help establish the exposure of bats to EBL2. The pilot will continue until bats go into hibernation. The Central Science Laboratory (CSL) at York is the primary contractor for the pilot work. CSL is sub-contracting The Veterinary Laboratory Agency, Weybridge to carry out the specialist laboratory tests, and Aberdeen University to undertake some of the fieldwork.

8. The separate tests are designed to reveal the presence of antibodies to EBL2 in the blood - an indication of exposure to the virus at some point during the animals life, but not necessarily of infection; and traces of the EBL virus RNA, or genetic material, in the bats saliva - indicating infection. Between April and June 2003, 183 bats of three species were caught and sampled. The species were Daubenton's bats, Natterer's Bat and Pipistrelle. Positive antibodies were found only in some Daubenton's bats where the data obtained so far suggests that between 6 and 19% of Daubenton's bats at the locations sampled were antibody positive. It is possible that the true level of exposure lies towards the lower end of this range. The spread of result is wide due to pooling of samples for laboratory analysis. This indicates that these antibody positive bats had been exposed to the virus at some stage of their life. No live virus was found in any bat. 30 were subject to detailed testing for the live virus. To further clarify the blood sampling antibody test, the pilot study is being extended. This will increase the sample size involved and increase the geographical spread of sampling.

Whilst this study has focussed on the species previously implicated in the November 2002 incident the results obtained so far indicate a level of antibody positive results in one species only, (Daubenton's), that is towards the lower end of levels recorded in bat populations within several other western European countries.

Other Studies:

9. In a complimentary study over the last 16 years, more than 3,200 already dead bats from across the UK have been tested for EBL. Only EBL2 has been found in the UK, in two individual Daubenton's bats, one from Sussex (1996) and one in Lancashire (2002). None of the other five known Lyssaviruses have been found in the UK (outside of animals and people known to have become infected whilst overseas). In 2003, more than 790 dead bats (118 to end July from Scotland) were sent for rabies testing. All were negative.



What does this mean for people finding bats?

10. The general public are advised not to touch bats. The Department of Health recommends that anyone whose work or leisure activities involve handling bats should be vaccinated against rabies. Anyone who has to move a stray or injured bat, where handling is unavoidable, should wear bite-proof gloves and use a cloth or a small towel, or a box and card, to pick-up and move it out of the reach of children, passers-by, cats and dogs.

11. Anyone who is bitten or scratched by a bat or has contact between an open cut or their mucous membranes (for example of their nose, eye or mouth) and a bats' saliva should wash the affected area immediately and thoroughly with soap and water and then seek medical attention. An effective post-exposure vaccine is available.

Further information and advice

'Bats and Human Health' leaflet, produced by SNH and SCIEH and available on the SNH and SCIEH websites.

'Rabies vaccination for bat handlers - Frequently asked questions' - produced by the Department of Health and available on The Bat Conservation Trust website. A parallel pilot study, funded by Defra, is being undertaken by VLA and CSL in Lancashire using similar techniques to the Scottish study. Sampling and analysis is not yet complete. Results from the Scottish Study should assist in the interpretation of results from the study in Lancashire and any future work elsewhere in the UK.

Via a link from the SNH website.

Anyone with a query about bats should contact:-

For general bat information and for details of local Bat Groups and bat carers - The National UK Bat Helpline run by The Bat Conservation Trust - 0845 1300 228 (9am to 5:30 pm Monday to Friday, except for English Bank Holidays).

For advice on bat roosts or dealing with grounded or stray bats (during office hours, Monday to Friday) - their local SNH office. See phone book or www.snh.gov.uk for details.

For advice on dealing with stray bats in Scotland (outside office hours) - the SNH Bat Helpline on 07774 161219.