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Living With Bats

Disease

While bats are associated with a number of diseases in other parts of the world, bats in Alaska are relatively free of diseases that pose threats to human health.

Rabies

If a human or pet has come into contact with a bat, click here.

Rabies is a virus that is not prevalent among bat populations in Alaska. Since the 1970s hundreds of bats have been tested for rabies. There are only four documented cases of bats with rabies in Alaska, all from Southeast Alaska and none of those bats transmitted the disease to a human. There has been only 1 case of rabies in a little brown bat, the species most likely to be encountered by humans. That bat was found in Ketchikan in 1993. The other three bats were all Keen’s myotis, a forest bat. Two of the rabid Keen’s bats were trapped by researchers on Prince of Wales Island (in 2006 and 2014) and the third was found in Wrangell in 2014.

Manifestations of Rabies in bats

  • Fly during daytime (this may also be typical of juvenile bats shortly after weaning)
  • Remain in “open” night roosts or in atypical places by day (also seen in healthy young bats)
  • Roost alone (healthy male bats may also roost singly)
  • Fly slowly or uncertainly, sometimes blundering into objects while in flight (also seen in healthy young bats)
  • Unable to fly; paralysis and weakness leading to tremors and vocalization or death
  • Move in an uncoordinated manner or thrash on the ground
  • Animals may be thin, dehydrated and hypothermic
  • Noise elicits squeaking from infected bats-healthy bats are generally quiet and motionless (this may also be typical of juvenile bats shortly after weaning)

Histoplasmosis

Histoplasmosis is a respiratory disease caused by a fungus that grows in soil enriched by bird and sometimes bat droppings. Lung infection can occur. The symptoms of Histoplasmosis are similar to pneumonia and the infection can become serious if not fatal if left untreated. Most human cases are found in the Ohio and Mississippi River valleys and adjacent areas where warm, humid conditions favor fungal growth. Cases of Histoplasmosis from bats have NOT occurred in Alaska.

For more information on Histoplasmosis:

White Nose Syndrome

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White nose syndrome

White Nose Syndrome (WNS) is a disease that affects hibernating bats. The disease was named after the white fungus found on the noses of most infected bats. WNS does not affect humans. The first known case of WNS appeared in New York in 2006. The disease has since spread across eastern and Midwestern North America. Scientists estimate that over six million bats have died of WNS. At some cave sites, nearly 100% of the bats have died. The fungus is transmitted primarily from bat to bat, but humans may help spread the fungus through contaminated clothing and caving gear. Although WNS has not been found in Alaska or the West — yet, the little brown bat, the most common and widespread bat found in Alaska, has been hit hard by the disease elsewhere in its range.

For more information on White Nose Syndrome: