Tularemia in Imported Hamsters

Tularemia in Imported Hamsters Laura MacDougall, MSc Epidemiologist, BCCD

Tularemia - Overview • Bacterial zoonosis caused by Fransicella tularensis • Multiple routes of infection • Clinical signs and severity of illness depend on route of transmission and strain • Type A and Type B

Tularemia - Overview(2) • F. tularensis biovar tularensis (type A) • Highly virulent in humans and animals • Most common biovar isolated in North America • Typically associated with rabbits, muskrats, beavers • F. tularensis biovar palaearctica (type B) • Generally less virulent • Most common biovar in Europe and Asia • Typically associated with rodents or wet environments

The Phone Call… • Sept 29, 2004 Manitoba Health informs BCCDC….

BC Public Health Concerns • Dwarf hamster death at BC distributor? • Did BC distributor sell any dwarf hamsters to local pet stores? • Was there illness in other animals from the same shipment? • Health of staff at BC pet distributor and BC pet stores?

BC Public Health Concerns • Dwarf hamster death at BC distributor? • 63 dwarf hamsters arrived ill • Separate cabinet in same stock room • All died within 1 week of arrival • Did BC distributor sell any dwarf hamsters to local pet stores? • NO!!! BUT…..

BC Public Health Concerns • Was there illness in other animals from the same shipment? • 12 chinchillas • 18 degus • 100 gerbils • Shipped to: • 13 BC pet stores • 12 in one chain • 2 ON locations, 3 AB, 1SK Chinchilla Degu Gerbil

Enhanced Rodent Surveillance • Obtained sales records with shipment dates and locations • Questionnaire to affected retail stores • Illness or mortality since Aug 25th • General and shipment-specific • Included in-store reports and customer reports • Quarantined, euthanized and tested remaining rodents

Enhanced Human Surveillance • Questionnaire to staff of BC pet stores • Integrated with rodent surveillance questionnaire • Face-to-face interviews at BC Distributor • Degree of exposure to dwarf hamsters • Serology • Employees of BC distributor • Symptomatic individuals from BC pet stores that received shipments

Results – Rodent Surveillance *The store that reported illness in the degu did not report illness in chinchillas. 6/12 chinchillas, 11/21 degus and 23/70 gerbils remained for testing - all negative by PCR

Results – Human Surveillance • BC Distributor • 4 employees tested • 1 with positive titre (1:128) • Blood drawn 5 wks after arrival of dwarf hamsters • Only person in contact with ill dwarf hamsters • Question: current or previous infection? • Retested at 6 months

Results – Human Surveillance (2) • BC Pet Stores • Human illness reported at 4 stores • 1 of these stores also reported an animal death from the suspect shipment • Mild flu-like symptoms • 1 individual with more severe sx: • Bitten by hamster (not from suspect shipment) • Headaches, sore throat, stuffy nose, vomiting, high fever, chills, body aches, swollen lips • Tested for tularemia = negative

BC Conclusions • Rapid public health response • Excellent cooperation with pet industry • Interaction with veterinarians critical • No evidence of spread from ill dwarf hamsters to others animals in shipment • No evidence of human infection among pet store employees • Asymptomatic infection at distributor?

What happened in Manitoba? • July 2004 • Mouse infestation in breeding shed • Poison used as control agent • August 2004 • Hamsters and guinea pigs begin dying • ?? Poison • Dwarf hamsters moved to another location • Breeding shed sealed and decontaminated • August / Sept • Dwarf hamsters distributed to BC, Minnesota, MN • October • Breeder shut down

Investigation - MN • Sampling of animals (n=72) • PCR positive animals included: • Hamsters and dwarf hamsters • 2 dogs, 1 rabbit – asymptomatic, +ve serology • Other environmental swabs – positive • Well water - negative • At least one human case identified • Field trapping studies of wild mice • F. tularensis of different strain! • Hypothesis – introduction from wild mice

Discussion points • Who takes ownership of a zoonotic disease issue? • Public Health authorities? • Animal authorities? MAFF? CFIA? • Recommendations to Pet Industry Joint Advisory Council (PIJAC) • Rodent-proofing for breeders • Disease prevention • Record-keeping; disease tracking • Consumer information

Questions?

Timeline of Public Health Actions • Wed Sep 29 – notified by Manitoba Health • Thu Sep 30 – contacted BC distributor • Fri Oct 1 • Contacted BC pet stores; communications docs prepared • Enhanced human/animal surveillance • Remaining animals isolated • Sat/Sun Oct 2/3 • Enhanced animal/human surv. continued • Mon Oct 4 • Euthanization/testing of BC animals from suspect shipment • Received notification that Type B identified in Minnesota • Letter to BC physicians

Timeline of Public Health Actions • Tues Oct 5 • Letter to BC Vets • Testing of BC rodents (AHC) • Oct 6, 7 • Preliminary negative results – BC animals • Negative human surveillance results • Fri Oct 8 • All animal results negative • Remaining animals in quarantine released • Public update on website; no press release

Tularemia in Imported Hamsters