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Frequency of delusional infestation by proxy and double delusional infestation in veterinary practice: observational
Peter Lepping1, Mark Rishniw1, Roland W Freudenmann1
1Peter Lepping, MRCPsych, MSc, Centre for Mental Health and Society, Bangor University, UK, and Mysore Medical College and Research Institute, India; Mark Rishniw, BVSc, MS, PhD, DACVIM, Veterinary Information Network, Davis, California, USA; Roland W. Freudenmann, MD, Department of Psychiatry and Psychotherapy, University of Ulm, Germany.
Background:
Nothing is known about the prevalence of delusional infestation in veterinary practice and the consequences for psychiatrists.
Aims:
We attempted to examine the frequency of delusional infestation among pet owners presenting their animals to veterinary clinics.
Method:
We conducted a survey among 32 663 veterinary clinicians who were members of the Veterinary Information Network.
Results:
The respondents had seen 724 suspected cases of delusional infestation by proxy in a pet. The clients were mainly White, female and 30-60 years old. They presented mainly dogs and cats, and the alleged infestation was mainly with arthropods or worms. Also, 252 clients claimed to be affected themselves; we termed this 'double delusional infestation'.
Conclusions:
Delusional infestation is seen frequently in veterinary practice. Psychiatrists need to be aware that patients may have pets they believe are infested.
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