The University of Sydney Page 1 ONE HEALTH TEAM. Australian Rickettsial Reference Laboratory

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1 Longevity of immunity following Q fever vaccination A Multidisciplinary One Health Team Presented by Associate Professor Nicholas Wood On behalf of NHMRC Q fever grant APP The University of Sydney Page 1 Dr Katrina Bosward Dr Nicholas Wood Dr Jacqueline Norris Dr Paul Sheehy Dr David Phalen Dr Navneet Dhand Prof. Peter McIntyre Australian Rickettsial Reference Laboratory ONE HEALTH TEAM Dr Jane Heller Prof Steven Graves Graduate students Dr Heather Gidding Amanda Shapiro, Emily Sellens Lucienne The University Downs of Sydney Page 2 1

2 Annual Q fever notifications Australia (2000 to 2016) National Q fever management program Approx. 10 notifications per week The University of Sydney Page Sources of C. burnetii for Humans Livestock Wildlife Goats, cattle, sheep Kangaroo tick Amblyomma triguttatum triguttatum Companion Animals Q fever in humans Peripartiuent cats + dogs and their offspring The University of Sydney Page 4 IMAGES:

3 Vaccine recommendations Immunisation Handbook > 15 years old At risk Abattoir workers, Veterinarians, veterinary nurses, veterinary students, professional dog and cat breeders, wildlife and zoo workers and laboratory personnel handling. The University of Sydney Page 5 Research questions - Immunisation Handbook Burden Increasing in non risk groups Longevity Immunity appears to be long lasting Booster doses not recommended The University of Sydney Page 6 3

4 How best to measure immune longevity and vaccine effectiveness? Vaccine failures Persistence of antibody Waning antibody The University of Sydney Page 7 68% (6978 out of 10196) = vaccine status unknown 2% (71/3218) had been vaccinated (Vaccine failures) The University of Sydney Page 8 4

5 The University of Sydney Page 9 Based on serology followed up to 3 years post infection only The University of Sydney Page 10 5

6 The University of Sydney Page 11 Aims and methods Aims: To measure the seroprevalence and Cell mediated immunity (CMI) in vets and correlate results with Q fever vaccine history. Methods: Questionnaire and blood sample collection at vet conferences Sample size: n=350 vets The University of Sydney Page 12 6

7 Data collected (n=364) Data fields Sex, age, current work postcode Length of employment Animal contact quantified Q fever vax status and year received Q fever disease status Serology Phase 1 and 2 IgG, IgM, IgA ARRL CMI using QDetect (IFN gamma release assay) The University of Sydney Page Q fever serology according to time since vaccination (n=208) % s e r o p o s i t i v e Phase 1 IgG positive Phase 2 IgG positive 0 Vax < 5 years Vax 5 to < 10 years Vax >10 to <15 years Time since vaccination Vax >15 yrs The University of Sydney Page 14 7

8 Cell mediated immunity testing Overall 70 vaccinated vets had CMI testing performed 10% were positive and all vaccinated <10 years In a subset vaccinated >10 years with both serology and CMI results measured(n=28) only 1 case was seropositive and none positive for CMI The University of Sydney Page 15 Unvaccinated (n=133) Phase 1 IgG positive (n=10, 8%) Phase 2 IgG positive (n=22, 17%) 7 subjects both phase 1 and 2 positive Overall seropositivity approx 25% in this high risk group indicating exposure The University of Sydney Page 16 8

9 Conclusion Overall approximately 80% of vaccinated are seronegative CMI testing n=70 10% had IFN gamma responses All vax within 10 years No indication to boost Vaccine failures not common however vaccine field often incomplete Planned follow on study to further investigate seronegative vaccinees Repeat skin prick test with serology/cmi pre and post The University of Sydney Page 17 Prevalence of Q fever in Australia Case notifications in 2016 Q Fever 540 (314 in 2009, 606 in 2015) Leptospirosis 138 Ornithosis (Psittacosis) 20 Brucellosis 18 Anthrax 0 Campylobacteriosis 24,244 Dog Bites (hospitalised) ~ 30,000! Q Fever is the most important of the direct notifiable zoonoses The University of Sydney Page 18 Source: 9