Blastomycosis Risk & Prevention

Who gets blastomycosis?

Image of a campsite with a fire

Anyone can get blastomycosis if they’ve been in an area where Blastomyces lives in the environment. People who participate in outdoor activities that expose them to wooded areas (such as forestry work, hunting, and camping), moist soil (such as by lakes or rivers), and disturbed soil (such as through digging or excavation) may be at higher risk for getting blastomycosis.1 People who have weakend immune systems may be more likely to develop severe blastomycosis than people who are otherwise healthy.2

Is blastomycosis contagious?

Usually not. Blastomycosis doesn’t spread between people or between people and animals through the air. In extremely rare cases, blastomycosis has been spread between infected people or animals through needlestick injuries, bites, or sexual contact.

Can my pets get blastomycosis?

Yes. Pets, particularly dogs, can get blastomycosis, but it is not contagious between animals and people through the air.3 The symptoms of blastomycosis in animals are similar to the symptoms in humans. If you are concerned about your pet’s risk of getting blastomycosis or if you think that your pet has blastomycosis, please talk to a veterinarian.

Blastomyces at my workplace

Should I be concerned about Blastomyces exposure at work?

Blastomyces only lives in certain areas of the world. If your job involves disturbing soil (for example, digging, excavation) in these areas and you develop symptoms of blastomycosis, please see a healthcare provider. Blastomycosis is treatable with antifungal medicines, but it is important to get diagnosed early.

What should I do if I think I’ve been exposed to Blastomyces at my workplace?

If you think you’ve been exposed to Blastomyces at work, you should contact your Occupational Health, Infection Control, Risk Management, or Safety/Security Department. If your workplace or laboratory doesn’t have these services, you should contact your local city, county, or state health department.

I work in a lab. Should I be concerned about Blastomyces exposures?

Blastomyces can be transmitted through needlestick injuries and inhalation of conidia from fungal cultures.4,5 There is no evidence showing that antifungal medication (i.e., prophylaxis) prevents people from getting sick with blastomycosis after a workplace exposure to Blastomyces. If you develop symptoms of blastomycosis, contact your healthcare provider.

I’m a veterinarian. Should I be concerned about patients with blastomycosis?

Although rare, blastomycosis can also be transmitted through needlestick injuries and animal bites.6,7 If you develop symptoms of blastomycosis, contact your healthcare provider.

How can I prevent blastomycosis?

There is no vaccine to prevent blastomycosis, and it may not be possible to completely avoid being exposed to the fungus that causes blastomycosis in areas where it is common in the environment. People who have weakened immune systems may want to consider avoiding activities that involve disrupting soil in these areas.

  1. Saccente M, Woods GL. Clinical and laboratory update on blastomycosis. Clin Microbiol Rev. 2010 Apr;23(2):367-81.
  2. Pappas PG, Threlkeld MG, Bedsole GD, Cleveland KO, Gelfand MS, Dismukes WE. Blastomycosis in immunocompromised patients. Medicine. 1993;72(5):311–25.
  3. Brömel C, Sykes JE. Epidemiology, diagnosis, and treatment of blastomycosis in dogs and cats. Clin Tech Small Anim Pract. 2005 Nov;20(4):233-9.
  4. Stevens DA, Clemons KV, Levine HB, Pappagianis D, Baron EJ, Hamilton JR, et al. Expert opinion: what to do when there is coccidioides exposure in a laboratory. Clin Infect Dis 2009 Sep;49(6):919–923
  5. Denton JF, Di Salvo AF, Hirsch ML. Laboratory-Acquired North American Blastomycosis. Laboratory-acquired North American blastomycosis. JAMA. 1967;199(12):935–936.
  6. Gnann JW, Bressler GS, Bodet CA, Avent CK. Human blastomycosis after a dog bite. Ann Intern Med. 1983 Jan;98(1):48-49.
  7. Ghatage P, Pierce KK, Wojewoda C, Mendelson N, Wilcock J, Nesbit R, et al. A veterinarian from Vermont presenting with a painful right index finger following a needlestick injury that occurred while caring for a dog. Clin Infect Dis. 2020 Sep;71(6):1577–1579.