Patricia C Priest1, Sandy Slow2, Stephen T Chambers2, Claire M Cameron3, Michelle N Balm4, Mark W Beale5, Timothy K Blackmore4, Andrew D Burns6, Dragana Drinković7, Juliet A Elvy8, Richard J Everts8, David A Hammer9, Paul J Huggan10, Christopher J Mansell10, Vicki M Raeder11, Sally A Roberts12, Murray C Robinson13, Vani Sathyendran13, Susan L Taylor14, Alyssa W Thompson15, James E Ussher16, Antje J van der Linden16, Melanie J Williams17, Roslyn G Podmore18, Trevor P Anderson18, Kevin Barratt18, Joanne L Mitchell18, David J Harte19, Virginia T Hope20, David R Murdoch21. 1. Department of Preventive and Social Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand. 2. Department of Pathology and Biomedical Science, University of Otago Christchurch, Christchurch, New Zealand. 3. Deans Office, Dunedin School of Medicine, University of Otago, Dunedin New Zealand. 4. Wellington Southern Community Laboratories, Wellington Hospital, Wellington, New Zealand. 5. Palmerston North Hospital, Palmerston North, New Zealand. 6. Hawke's Bay Hospital, Hastings, New Zealand. 7. North Shore Hospital, Takapuna, Auckland, New Zealand. 8. Nelson Hospital, Nelson, New Zealand. 9. Whangarei Hospital, Whangarei, New Zealand. 10. Waikato Hospital, Hamilton, New Zealand. 11. Grey Base Hospital, Greymouth, New Zealand. 12. Auckland City Hospital, Auckland, New Zealand. 13. PathLab, Tauranga, New Zealand. 14. Middlemore Hospital, Otahuhu, Auckland, New Zealand. 15. Gisborne Hospital, Gisborne, New Zealand. 16. Southern Community Laboratories, Dunedin Hospital, Dunedin, New Zealand. 17. Taranaki Base Hospital, New Plymouth, New Zealand. 18. Canterbury Health Laboratories, Christchurch, New Zealand. 19. Legionella Reference Laboratory, Institute of Environmental Science and Research, Porirua, New Zealand. 20. Health Programme, Institute of Environmental Science and Research, Upper Hutt, New Zealand. 21. Department of Pathology and Biomedical Science, University of Otago Christchurch, Christchurch, New Zealand. Electronic address: david.murdoch@otago.ac.nz.
Abstract
BACKGROUND: Legionnaires' disease is under-diagnosed because of inconsistent use of diagnostic tests and uncertainty about whom to test. We assessed the increase in case detection following large-scale introduction of routine PCR testing of respiratory specimens in New Zealand. METHODS: LegiNZ was a national surveillance study done over 1-year in which active case-finding was used to maximise the identification of cases of Legionnaires' disease in hospitals. Respiratory specimens from patients of any age with pneumonia, who could provide an eligible lower respiratory specimen, admitted to one of 20 participating hospitals, covering a catchment area of 96% of New Zealand's population, were routinely tested for legionella by PCR. Additional cases of Legionnaires' disease in hospital were identified through mandatory notification. FINDINGS: Between May 21, 2015, and May 20, 2016, 5622 eligible specimens from 4862 patients were tested by PCR. From these, 197 cases of Legionnaires' disease were detected. An additional 41 cases were identified from notification data, giving 238 cases requiring hospitalisation. The overall incidence of Legionnaires' disease cases in hospital in the study area was 5·4 per 100 000 people per year, and Legionella longbeachae was the predominant cause, found in 150 (63%) of 238 cases. INTERPRETATION: The rate of notified disease during the study period was three-times the average over the preceding 3 years. Active case-finding through systematic PCR testing better clarified the regional epidemiology of Legionnaires' disease and uncovered an otherwise hidden burden of disease. These data inform local Legionnaires' disease testing strategies, allow targeted antibiotic therapy, and help identify outbreaks and effective prevention strategies. The same approach might have similar benefits if applied elsewhere in the world. FUNDING: Health Research Council of New Zealand.
BACKGROUND:Legionnaires' disease is under-diagnosed because of inconsistent use of diagnostic tests and uncertainty about whom to test. We assessed the increase in case detection following large-scale introduction of routine PCR testing of respiratory specimens in New Zealand. METHODS: LegiNZ was a national surveillance study done over 1-year in which active case-finding was used to maximise the identification of cases of Legionnaires' disease in hospitals. Respiratory specimens from patients of any age with pneumonia, who could provide an eligible lower respiratory specimen, admitted to one of 20 participating hospitals, covering a catchment area of 96% of New Zealand's population, were routinely tested for legionella by PCR. Additional cases of Legionnaires' disease in hospital were identified through mandatory notification. FINDINGS: Between May 21, 2015, and May 20, 2016, 5622 eligible specimens from 4862 patients were tested by PCR. From these, 197 cases of Legionnaires' disease were detected. An additional 41 cases were identified from notification data, giving 238 cases requiring hospitalisation. The overall incidence of Legionnaires' disease cases in hospital in the study area was 5·4 per 100 000 people per year, and Legionella longbeachae was the predominant cause, found in 150 (63%) of 238 cases. INTERPRETATION: The rate of notified disease during the study period was three-times the average over the preceding 3 years. Active case-finding through systematic PCR testing better clarified the regional epidemiology of Legionnaires' disease and uncovered an otherwise hidden burden of disease. These data inform local Legionnaires' disease testing strategies, allow targeted antibiotic therapy, and help identify outbreaks and effective prevention strategies. The same approach might have similar benefits if applied elsewhere in the world. FUNDING: Health Research Council of New Zealand.
Authors: Ali Mohammadi; Stephen T Chambers; Amy Scott-Thomas; John G Lewis; Trevor Anderson; Ros Podmore; Jonathan Williman; David Murdoch; Sandy Slow Journal: J Clin Microbiol Date: 2020-10-21 Impact factor: 5.948
Authors: Jan Haviernik; Krista Dawson; Trevor Anderson; David Murdoch; Stephen Chambers; Patrick Biggs; Simone Cree; Sandy Slow Journal: Microbiol Resour Announc Date: 2020-01-30
Authors: Sandy Slow; Trevor Anderson; David R Murdoch; Samuel Bloomfield; David Winter; Patrick J Biggs Journal: Sci Rep Date: 2022-04-06 Impact factor: 4.379