The proband was a 44-year-old female certified nursing aide who presented with marginally elevated squamous erythema on the dorsal side of the right upper arm. We isolated
Trichophyton glabrum (
T. glabrum) from the lesion and assigned the diagnosis of tinea corporis. Subsequently, we examined the staffand residents of the nursing home for
T. glabrum using the hairbrush (HB; 90 bristles) method. Thirty-nine employees and 92 residents were examined. None of the employees had a tinea lesion and their HB samples were negative.
T. glabrum was identified in 14 HB-positive samples from the residents. Examination of the head of these patients revealed that 2 cases had black dot ringworm, 4 had a pityriasis-like rash, and 8 were asymptomatic carriers. The degree of disability in these patients was severe according to classification of the Ministry of Health, Labour and Welfare, meaning that they either could not leave their bed or stand alone and were totally dependent on help from nursing aides. Therefore, we inferred that the fungus was transmitted from the head of a resident to the arm of the aide. We were not able to identify the source among the residents, but concluded that the usage of hairbrushes during bathing of residents must be the reason for the outbreak of HB-positive cases.
View full abstract