Actinomyces

Actinomyces are a genus of filamentous or rod-shaped bacteria that are typically found on the mucosal surfaces of warm-blooded vertebrates, particularly in the oral cavity. While often harmless, some species can become pathogenic, causing a chronic infection known as actinomycosis. This infection is characterized by abscesses and draining sinus tracts that exude sulfur granules.12

Actinomyces are part of a larger group called actinomycetes, which are known for their filamentous growth, resembling fungi. Many actinomycetes, including some Actinomyces species, are found in soil and are beneficial, serving as sources of antibiotics like streptomycin. However, certain species, such as Actinomyces bovis in cattle and A. israeli in humans, can cause disease when mucous membrane integrity is compromised. Treatment for actinomycosis typically involves antibiotics and sometimes surgery.32