The Canadian data in some areas may be confounded or explained by the tendency to establish indigenous communities in wooded, riparian, northern areas corresponding to the core habitat of B. dermatitidis, often with known B. dermatitidis habitats such as woodpiles and beaver constructions in the near vicinity. Communicability
Blastomycosis is not considered contagious, either among humans or between animals and humans. However, there are a very small number of cases of human-to-human transmission of B. dermatitidis related to dermal contact or sexual transmission of disseminated blastomycosis of the genital tract among spouses. History
The organisms causing blastomycosis have existed for millions of years. The pathogenic group of onygenalean fungi that give rise to conditions including blastomycosis and histoplasmosis emerged approximately 150 million years ago. The most closely related blastomycosis-causing fungi, Blastomyces dermatitidis and Blastomyces gilchristii, diverged during the Pleistocene, approximately 1.9 million years ago.At the Koster Site in Illinois, evidence pointing to possible blastomycosis infections among Late Woodland Native Americans has been identified. At that site, Dr. Jane Buikstra found evidence for what may have been an epidemic of a serious spinal disease in adolescents and young adults. Several of the skeletons showed lesions in the spinal vertebrae in the lower back. There are two modern diseases that produce lesions in the bone similar to the ones Dr. Buikstra found in these prehistoric specimens: spinal TB and blastomycosis. The bony lesions in these two diseases are practically identical.
In most such cases, the infection in the dog becomes apparent before the human infection. This may be due to a shortened incubation period, caused by the dog inhaling larger quantities of Blastomyces spores than the human.In veterinary care, blastomycosis is typically treated with itraconazole. 70% of treated dogs respond to medication and recover. In dogs as in humans, the prognosis for blastomycosis depends on the severity of the symptoms. Additional images
See also
Histoplasmosis
Paracoccidioidomycosis

References
Further reading
Castillo CG, Kauffman CA, Miceli MH (2016). "Blastomycosis". Infectious Disease Clinics of North America. 30 (1): 247–264. doi:10.1016/j.idc.2015.10.002. PMID 26739607. (Review). McBride JA, Gauthier GM, Klein BS (2017). "Clinical Manifestations and Treatment of Blastomycosis". Clinics in Chest Medicine. 38 (3): 435–449. doi:10.1016/j.ccm.2017.04.006. PMC 5657236. PMID 28797487. PMC 5657236 (Review)

External links

 Media related to Blastomycosis at Wikimedia Commons
Blastomyces at the US National Library of Medicine Medical Subject Headings (MeSH)
NIH Encyclopedia Blastomycosis