Introduction: Ornithonyssus bacoti, known as tropical rat mite, is a blood-feeding ectoparasitic arthropod belonging to the family Macronyssidae. At night the parasites search for their hosts and seek dark hiding places during the daytime. O. bacoti primarily infests rodents, but it has been reported also in other small mammals and in humans if suitable preferential hosts are unavailable or in the case of close contact with infected animals and environments (Beck W , 2008, Travel Medicine and Infectious Disease, 6: 245–249). In humans the mite is responsible for dermatologic lesions known as rat mite dermatitis. This study reports O. bacoti infestation in pet Campbell's dwarf hamsters and in the owners. Materials and Methods: In the month of December 2012 a Campbell's dwarf hamster with dermatological problems was presented. The subject, a female about 1 year old, was housed in a hamster cage with two other females of the same age. All subjects had been purchased from the same pet shop, at different times between October and December of 2012. After about two weeks from the introduction of the third hamster, the owners noticed a gradual increase in itching in one of the two hamster previously owned. At the same time, one of the six members of the family, a child of 11 years showed dermatologic symptoms including pruritus, papules and scabs on the trunk, arms and legs. The affected child lived in a room where the hamster cage was housed. After two further weeks, two other members of the family showed the same clinical signs. For mite collection, on the infested pet the Scotch test was performed, while the cage was inspected and mites collected with a needle. Isolated mites were preserved in 80% ethanol , mounted by using Hoyer's medium application according to conventional techniques, and microscopically observed for species identification. Results: At the scotch test, the hamster was positive for mites. From the bottom of the cage, a large number of mites were collected. Mites were highly variable in size and in color, from reddish to dark brown. All isolated mites were adult females ranging from 937 to1339 µm in length X 453.2-957.9 µm in width (mean 1033.8 µm X 556.2 µm). On the basis of morophology and chaetotaxy, isolated mites were identified with the species O. bacoti. Conclusion: Hamsters were treated with an acaricide, cage were thoroughly cleaned and decontaminated with an acaricide containing permethrin. The house was also disinfected and a professional exterminator was recommended .
Ornithonyssus bacoti infestation in Campbell's dwarf hamsters (Phodopus campbelli) and rat mite dermatitis in the owners.
PERRUCCI, STEFANIA
2014-01-01
Abstract
Introduction: Ornithonyssus bacoti, known as tropical rat mite, is a blood-feeding ectoparasitic arthropod belonging to the family Macronyssidae. At night the parasites search for their hosts and seek dark hiding places during the daytime. O. bacoti primarily infests rodents, but it has been reported also in other small mammals and in humans if suitable preferential hosts are unavailable or in the case of close contact with infected animals and environments (Beck W , 2008, Travel Medicine and Infectious Disease, 6: 245–249). In humans the mite is responsible for dermatologic lesions known as rat mite dermatitis. This study reports O. bacoti infestation in pet Campbell's dwarf hamsters and in the owners. Materials and Methods: In the month of December 2012 a Campbell's dwarf hamster with dermatological problems was presented. The subject, a female about 1 year old, was housed in a hamster cage with two other females of the same age. All subjects had been purchased from the same pet shop, at different times between October and December of 2012. After about two weeks from the introduction of the third hamster, the owners noticed a gradual increase in itching in one of the two hamster previously owned. At the same time, one of the six members of the family, a child of 11 years showed dermatologic symptoms including pruritus, papules and scabs on the trunk, arms and legs. The affected child lived in a room where the hamster cage was housed. After two further weeks, two other members of the family showed the same clinical signs. For mite collection, on the infested pet the Scotch test was performed, while the cage was inspected and mites collected with a needle. Isolated mites were preserved in 80% ethanol , mounted by using Hoyer's medium application according to conventional techniques, and microscopically observed for species identification. Results: At the scotch test, the hamster was positive for mites. From the bottom of the cage, a large number of mites were collected. Mites were highly variable in size and in color, from reddish to dark brown. All isolated mites were adult females ranging from 937 to1339 µm in length X 453.2-957.9 µm in width (mean 1033.8 µm X 556.2 µm). On the basis of morophology and chaetotaxy, isolated mites were identified with the species O. bacoti. Conclusion: Hamsters were treated with an acaricide, cage were thoroughly cleaned and decontaminated with an acaricide containing permethrin. The house was also disinfected and a professional exterminator was recommended .I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
