Attempted isolation of Blastomyces dermatitidis from the nares of dogs: Northern Wisconsin, USA.

The nasal cavities of domestic animals may concentrate and allow isolation of environmentally acquired fungal pathogens. We obtained two swabs each from the nares of 110 asymptomatic, physically normal dogs from a veterinary practice in Eagle River, WI, USA, an area highly endemic for blastomycosis. Four of the tested dogs had past histories of blastomycosis. Samples were placed on yeast extract phosphate (Smith's) media at 20 degrees C but growth of Blastomyces dermatitidis was not observed on any of the 220 cultures. One dog developed cytologically confirmed B. dermatitidis one month following culture of its samples, 6 died of other illnesses, while 91/103 dogs completing follow-up have remained asymptomatic for three years. We did not observe nasal colonization by B. dermatitidis in this population of dogs with potential for sniffing and digging in an environment highly endemic for this fungus.