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One health (Amsterdam, Netherlands)2017; 3; 29-33; doi: 10.1016/j.onehlt.2017.02.003

An outbreak of psittacosis at a veterinary school demonstrating a novel source of infection.

Abstract: In November 2014, New South Wales Health was notified of a cluster of respiratory illness in a veterinary school. Active case finding identified another case at a local equine stud. All cases had exposure to the equine fetal membranes of Mare A. This tissue subsequently tested positive for Chlamydia psittaci using quantitative real-time polymerase chain reaction. We conducted a cohort study of the university and stud farm staff to determine risk factors for disease. Nine people were exposed to the fetal membranes of Mare A. Of these, five cases of psittacosis were identified. Two required hospital admission. Contact with birds was not associated with illness (RR = 0.5, 95% CI = 0.09-2.73). People who had direct contact with the abnormal fetal membranes were more likely to develop disease (RR = 11.77, 95% CI = 1.02-∞). The emergence of an association between horse exposure and C. psittaci infection has important implications for the prevention and control of psittacosis. Article summary line: Investigation of an outbreak of psittacosis in a rural veterinary school demonstrates novel source of infection for psittacosis through exposure to abnormal equine fetal membranes.
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Publication Date: 2017-02-24 PubMed ID: 28616500PubMed Central: PMC5454149DOI: 10.1016/j.onehlt.2017.02.003Google Scholar: Lookup
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  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This study investigates an outbreak of psittacosis, a type of respiratory disease, at a veterinary school in New South Wales. The research found that the disease was contracted from exposure to equine fetal membranes, a previously unknown source of infection.

Context and Objectives of the Study

  • The study was sparked by an outbreak of respiratory illness at a veterinary school in New South Wales, in November 2014.
  • The research team aimed to identify the source of the psittacosis and determine risk factors for the disease.
  • Previous studies mainly identified birds as carriers of psittacosis. Identifying a new source of infection could have significant implications for disease prevention and control.

Methodology of the Investigation

  • The team conducted a cohort study involving staff from the university and a local stud farm, as another case was also identified there.
  • They used a quantitative real-time polymerase chain reaction test to analyze equine fetal membranes from the mare that caused the outbreak.
  • The study involved identifying and recording symptoms among staff members who had been exposed to the membranes.

Key Findings

  • Nine people had been exposed to the mare’s abnormal fetal membranes, out of which five developed psittacosis.
  • The study found no association between contact with birds and illness, contrary to previously held views.
  • People who had direct contact with the abnormal fetal membranes were significantly more likely to develop psittacosis, establishing a new source of disease transmission, different from the generally accepted origin.

Implications of the Study

  • The findings challenge assumptions about the primary sources of psittacosis and show that equine fetal membranes can be a source of infection.
  • The results of the study have implications for prevention and control strategies, which may need to be reconsidered in veterinary schools and related environments.

Conclusion

  • This investigation revealed a previously unknown source of psittacosis infection and could play a crucial role in developing new strategies for preventing and controlling the disease on veterinary premises.

Cite This Article

APA
Chan J, Doyle B, Branley J, Sheppeard V, Gabor M, Viney K, Quinn H, Janover O, McCready M, Heller J. (2017). An outbreak of psittacosis at a veterinary school demonstrating a novel source of infection. One Health, 3, 29-33. https://doi.org/10.1016/j.onehlt.2017.02.003

Publication

One health (Amsterdam, Netherlands)
ISSN: 2352-7714
NlmUniqueID: 101660501
Country: Netherlands
Language: English
Volume: 3
Pages: 29-33

Researcher Affiliations

Chan, Jocelyn
  • Health Protection New South Wales (NSW), NSW Health, North Sydney, NSW, Australia.
  • National Centre for Epidemiology and Population Health (NCEPH), Australian National University, Canberra, Australian Capital Territory (ACT), Australia.
Doyle, Bridget
  • Public Health Unit, Murrumbidgee Local Health District, Albury, NSW, Australia.
Branley, James
  • Pathology West Nepean, Penrith, NSW, Australia.
Sheppeard, Vicky
  • Health Protection New South Wales (NSW), NSW Health, North Sydney, NSW, Australia.
Gabor, Melinda
  • State Veterinary Diagnostic Laboratory, Department of Primary Industry, Menangle, NSW, Australia.
Viney, Kerri
  • National Centre for Epidemiology and Population Health (NCEPH), Australian National University, Canberra, Australian Capital Territory (ACT), Australia.
Quinn, Helen
  • National Centre for Immunisation Research and Surveillance of Vaccine Preventable Diseases (NCIRS), The Children's Hospital at Westmead, Sydney, NSW, Australia.
  • Discipline of Paediatrics and Child Health, University of Sydney, The Children's Hospital at Westmead, Sydney, NSW, Australia.
Janover, Orly
  • Public Health Unit, Murrumbidgee Local Health District, Albury, NSW, Australia.
McCready, Michael
  • The University of New South Wales, Sydney, NSW, Australia.
Heller, Jane
  • School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW, Australia.

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