Outbreak of tropical rat mite (Ornithonyssus bacoti) dermatitis in a home for disabled persons

Five mentally handicapped individuals living in a home for disabled
persons in Southern Germany were seen in our outpatient department
with pruritic, red papules predominantly located in groups on the
upper extremities, neck, upper trunk and face. Over several weeks
40 inhabitants and 5 caretakers were affected by the same rash.
Inspection of their home and the sheds nearby disclosed infestation
with rat populations and mites. Finally the diagnosis of tropical
rat mite dermatitis was made by the identification of the arthropod
Ornithonyssus bacoti or so-called tropical rat mite. The patients
were treated with topical corticosteroids and antihistamines. After
elimination of the rats and disinfection of the rooms by a
professional exterminator no new cases of rat mite dermatitis
occurred. The tropical rat mite is an external parasite occurring
on rats, mice, gerbils, hamsters and various other small mammals.
When the principal animal host is not available, human beings can
become the victim of mite infestation. Copyright (c) 2007 S. Karger
AG, Basel