Actinomycosis of the Neck
Despite its name, actinomycosis is not a fungal infection. Originally thought to be a mycosis of people who chewed on straw or grass, the bacteria that causes this condition (Actinomyces species) are actually anaerobic organisms that thrive in weakened or already-infected areas of the mouth and neck, and occasionally infected areas of intestine or appendix.
Prior to antibiotics and modern hygienic standards, the incidence of this infection was as high as 1 in 100,000 people, but it was still considered a rare disease of humans. In animals, however, Actinomyces cause a condition called lumpy jaw, which was (and is) far more common than human infection.
These days, the bacteria is generally seen in those who have poor dental hygiene, or who have had x-ray therapy to their gums and oral mucosa to kill cancerous cells. It’s sensitive to penicillin and other basic antibiotics, with no resistances noted as of yet, but it can take months to years to completely clear up an infection.
Introduction to Dermatology. Norman Walker, 1911.