title: Clinical and molecular investigation of a canine distemper outbreak and vector-borne infections in a group of rescue dogs imported from Hungary to Switzerland.
abstract: BACKGROUND
  Canine distemper virus (CDV) is a major pathogen of dogs and wild carnivores worldwide. In Switzerland, distemper in domestic dogs is rarely reported. In recent years, the import of dogs from Eastern Europe to Switzerland has steadily increased. In the present study, we describe a distemper outbreak in 15 rescue dogs that were imported from Hungary to Switzerland by an animal welfare organisation. The data on vaccination and medical history were recorded (14 dogs), and the samples were collected to investigate CDV and vector-borne infections (13 dogs) and canine parvovirus infection (12 dogs). The dogs were monitored for six months.
  
  
  RESULTS
  One dog was euthanised directly after import. Thirteen dogs showed clinical signs after arrival, i.e., diarrhoea (57 %), coughing (43 %) and nasal and/or ocular discharge (21 %); radiographic findings that were compatible with bronchopneumonia were present in four dogs. CDV infection was diagnosed in 11 dogs (85 %); 10 dogs (91 %) tested PCR-positive in conjunctival swabs. Vector-borne infections (Babesia spp., Leishmania infantum, Dirofilaria immitis) were found in 4 dogs (31 %). Three dogs were hospitalized, and six dogs received ambulatory therapy for up to two months until recovery. None of the dogs developed neurological disease. CDV shedding was detected for a period of up to four months. Because dogs were put under strict quarantine until CDV shedding ceased, CDV did not spread to any other dogs. The CDV isolates showed 99 % sequence identity in the HA gene among each other and belonged to the Arctic-like lineage of CDV.
  
  
  CONCLUSIONS
  The present study highlights the imminent risks of spreading contagious viral and vector-borne infections through the non-selective import of sick dogs and dogs with incomplete vaccination from Eastern Europe. CDV shedding was detected for several months after the cessation of clinical signs, which emphasised the roles of asymptomatic carriers in CDV epidemiology. A long-term follow-up using sensitive PCR and strict quarantine measures is of upmost importance in preventing the spread of infection. Dog owners and animal welfare organisations should be educated regarding the importance of complete vaccinations and the impact of dog imports on the spread of viral and vector-borne pathogens.
authors.affiliation: Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. bwilli@vetclinics.uzh.ch.|Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. bwilli@vetclinics.uzh.ch.
authors.forename: Barbara
authors.initials: B
authors.lastname: Willi
authors.affiliation: Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. aspiri@vetclinics.uzh.ch.|Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. aspiri@vetclinics.uzh.ch.
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Spiri
authors.affiliation: Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. mmeli@vetclinics.uzh.ch.|Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. mmeli@vetclinics.uzh.ch.
authors.forename: Marina L
authors.initials: ML
authors.lastname: Meli
authors.affiliation: Institute of Parasitology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. felix.grimm@uzh.ch.
authors.forename: Felix
authors.initials: F
authors.lastname: Grimm
authors.affiliation: Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. lbeatrice@vetclinics.uzh.ch.
authors.forename: Laura
authors.initials: L
authors.lastname: Beatrice
authors.affiliation: Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. briond@vetclinics.uzh.ch.
authors.forename: Barbara
authors.initials: B
authors.lastname: Riond
authors.affiliation: Kleintierpraxis Dres. med. vet. Rohner & Bley, Niederglatt, Switzerland. bleytony@gmail.com.
authors.forename: Tim
authors.initials: T
authors.lastname: Bley
authors.affiliation: Kleintierpraxis Dr. med. vet. Rolf Jordi, Gümligen, Switzerland. rolf.jordi@bluewin.ch.
authors.forename: Rolf
authors.initials: R
authors.lastname: Jordi
authors.affiliation: Clinic of Diagnostic Imaging, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. mdennler@vetclinics.uzh.ch.
authors.forename: Matthias
authors.initials: M
authors.lastname: Dennler
authors.affiliation: Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. rhofmann@vetclinics.uzh.ch.|Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. rhofmann@vetclinics.uzh.ch.
authors.forename: Regina
authors.initials: R
authors.lastname: Hofmann-Lehmann
mesh_terms: D000818:Animals; D001403:Babesia / Q000302:isolation & purification; D001404:Babesiosis / Q000175:diagnosis* / Q000453:epidemiology; D004183:Dirofilaria immitis / Q000302:isolation & purification; D004184:Dirofilariasis / Q000175:diagnosis* / Q000453:epidemiology; D004196:Disease Outbreaks / Q000662:veterinary*; D004216:Distemper / Q000453:epidemiology / Q000821:virology*; D004217:Distemper Virus, Canine / Q000235:genetics; D004285:Dogs; D005260:Female; D006814:Hungary / Q000453:epidemiology; D007303:Insect Vectors / Q000821:virology*; D018314:Leishmania infantum / Q000302:isolation & purification; D007898:Leishmaniasis, Visceral / Q000175:diagnosis / Q000453:epidemiology / Q000662:veterinary*; D008297:Male; D008969:Molecular Sequence Data; D013557:Switzerland / Q000453:epidemiology; D017201:Virus Shedding