1. About Bats
  2. Threats to bats
  3. White-nose syndrome
  4. Frequently asked questions

Frequently asked questions

What is white-nose syndrome?

White-nose syndrome (WNS) is the name used to describe a group of symptoms associated with the deaths of millions of bats in North America. These symptoms are:

  • bats with a white fungus (Pseudogymnoascus destructans),particularly around the nose, but also on the wings, ears and/or tail;
  • bats clustered near the entrance of hibernacula, or in areas not normally identified as winter roost sites;
  • bats flying outside during the day in temperatures at or below freezing; and/or
  • dead or dying bats in or near hibernation sites.

In isolation, the symptoms do not necessarily indicate WNS; for example bats with a white fungus might otherwise be perfectly healthy. Conversely, not all bats affected with WNS will necessarily be found with white fungus on them.

What causes WNS?

The fungus, P. destructans (previously known as Geomyces destructans), has been confirmed as the cause of WNS. It is a soil fungus that grows optimally at the temperatures found in winter hibernacula, which irritates the bats and causes energetically-expensive arousals from hibernation, loss of body fat and starvation. Recent research has also suggested that infections on the wing membranes of bats may lead to dehydration thereby increasing the frequency of arousals. Additionally where the fungus causes lesions in the wing membrane, this may affect the fitness of bats that survive the hibernation period. It is very likely that P. destructans was introduced into North America from Europe.

Have there been any cases of WNS in the UK or Europe?

In Europe the fungus P. destructans was originally identified on a single hibernating bat in France in 2009. It has been positively identified in at least 17 European countries (from molecular analysis). This includes the UK where the fungus was first discovered in 2013, through a combination of active and passive surveillance projects.

Unlike North America, there have been no reports of mass die offs and therefore there is no evidence of the syndrome (WNS) itself in Europe. It is thought probable that European bats have a resistance to the fungus, possibly evolved over thousands of years of exposure

What happened when cases of P. destructans were first confirmed in the UK?

When P. destructans was confirmed as being present in the UK in July 2013, BCT notified bat workers through communications to bat groups, NBMP volunteers and bat carers. We requested that all bat workers continue their usual activities, continue to follow the protocols and submit data to BCT/APHA as this helps us to develop a better understanding of the fungus’ presence in the UK.

The guidelines for bat workers and bat carers were revised following the initial discovery and are reviewed annually ahead of the hibernation season, following updates from researchers in the UK, Europe and North America.

What is being asked of UK underground workers?

Primarily, we are asking all visitors to underground hibernation sites to remain vigilant for the symptoms commonly associated with WNS as part of their usual survey activities. We are not requesting that bat workers or other underground users do additional checks for signs of WNS. Furthermore, licensed bat workers should not handle suspect live bats; in cases where a live bat is found with a suspect fungus, a sample should be taken from visible fungal lesions whilst the bat is in a hanging position.

All UK bats and their roosts are fully protected under UK and European legislation. This means that you must not enter a known hibernaculum without an appropriate licence or a licensed bat worker, and disturbance to bats during licensed work must be kept to a minimum.

What decontamination products are recommended?

The decontamination products you use need to contain an anti-fungal agent. Prior to use of a disinfectant please check the relevant product data sheets to ensure anti-fungal action and the correct dilution rates for use. An increased concentration should be used if boots, equipment, etc. are wet.

There are a number of disinfectants available that have anti-fungal properties:

  • Ark-Klens – available from Vetark (the ‘ready to use’ product is £6.72; November 2021 price)
  • Anigene – available from various suppliers including online from Amazon (from £21.99 per litre of concentrate; November 2021 price)
  • Virkon S (DuPont) – available from various suppliers including online from SPH Supplies (£19.50 for 1kg box; November 2021 price)
  • F10 – available from Meadows Animal Health Care (£11.50 for 1 litre of ready to use disinfectant; November 2021 price)
  • Lysol (Reckitt Benckiser) – available from various suppliers including Amazon (various sizes and prices)

For easy application, we suggest decanting ‘ready to use’ disinfectant into a trigger spray container, such as those available from hardware stores (check usage instructions on the product you have purchase). For example Arco has a trigger spray at £3.99 (excl. VAT; November 2021 price).

The skin cleaner Hibiscrub is also a useful antifungal for use on hands. This is available from various suppliers including via Amazon (£7.00; November 2021 price). You can, alternatively, wash your hands thoroughly with soap and water. However, this method can be more difficult in the field.

Please note: general antibacterial hand gels are NOT effective against fungal spores.

Threats to bats