[Animal hoarding: a mental disorder with implications for public health]

Animal hoarding (AH) is a mental disorder that is characterised by an excessive number of kept animals, inability to maintain minimal standards of animal care and hygiene, and deficient insight into the thereby developing failures and problems. Although AH as a disease concept is neither represented in the DSM-5 nor the ICD-10, it may be classified as a subform of the hoarding disorder (DSM-5 300.3) that was implemented in the DSM-5 as an obsessive-compulsive disorder. Due to the hygienic deficiencies of the living spaces and the insufficient keeping of animals there is an increased risk of epizootic diseases and zoonoses. Specific epidemiological studies do not exist, however, women seem to be affected more frequently. AH is diagnosed mostly in late adulthood. Besides thorough somatic and psychiatric medical diagnostics, cooperation with the veterinary offices and authorities is usually necessary. Comorbid mental disorders (particularly depressive, obsessive-compulsive and personality disorders) are frequent. Currently, no evidence-based therapies exist. Social therapy and cognitive-behavioural psychotherapeutic interventions as well as sufficient treatment of comorbid mental disorders are recommended.