Growing on dead or dying birch trees, the fungus Birch Polypore (Piptoporus betulinus) can be found around the globe in temperate climates wherever birch trees occur.
Birch Polypore's 15 minutes of fame came when it was discovered among the remains of Oetzi the Iceman, whose 5,300 year old mummified body was found 1991 at the border of Austria and Italy in a glacial ice cave.
The general consensus is that Oetzi the Iceman used the Birch Polypore against an infection of the intestinal parasite Trichuris trichuria, of which eggs were found among his remains. 
The traditional use of Birch Polypore extract does indeed include use as an anti-parasitic agent, as well as to stop bleeding, and as an antimicrobial agent in general. 
Two studies from 1997 found that certain Birch Polypore extracted compounds were anti-inflammatory,  and that they specifically helped reduce skin inflammation. 
In terms of its antibiotic properties, Birch Polypore extract has been found effective against Bacillus megateterium.  One antibiotic compound that has been isolated from Birch Polypore is known as Piptamine.  Medicinal mushroom expert Paul Stamets proposes that Birch Polypore extract be tested for its effectiveness against anthrax Bacillus anthracis. 
Another compound that is found in high concentrations in Birch Polypore is known as Betulinic Acid. Produced by the birch trees upon which this mushroom grows, Betulinic Acid gets extracted and concentrated by the Birch Polypore. A 1995 study on melanoma found that Betulinic Acid killed the malignant melanoma cells but did not harm healthy cell tissue.  Seven years later, another study showed that Birch Polypore extract inhibited the enzymes that promote tumor cell growth, which may help explain how Betulinic Acid works against cancer. 
A 2001 study of Betulinic Acid derivatives from Birch Polypore also reported anti-viral properties. In a study on HIV, these compounds were found to block the reproduction of HIV. 
American medicinal mushroom expert Paul Stamets filed a patent on his proprietary Birch Polypore extraction methods in 2004 after researchers at the National Institute of Health (NIH) and the U.S. Army Medical Research Institute of Infectious Disease (USAMRIID) reported that his Birch Polypore extract selectively killed the cowpox and vaccinia viruses without harming human cells. 
Note: The statements on this page have not been evaluated by the Food and Drug Administration. This article is not intended to diagnose, treat, cure or prevent any disease. Always consult a licensed medical practitioner before using any herb (or mushroom) for medicinal purposes.