1
|
Mathews KO, Phalen D, Norris JM, Stenos J, Toribio JA, Wood N, Graves S, Sheehy PA, Nguyen C, Bosward KL. Serological Evidence of Exposure to Spotted Fever Group and Typhus Group Rickettsiae in Australian Wildlife Rehabilitators. Pathogens 2021; 10:pathogens10060745. [PMID: 34204809 PMCID: PMC8231516 DOI: 10.3390/pathogens10060745] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/15/2021] [Accepted: 05/28/2021] [Indexed: 12/14/2022] Open
Abstract
Rickettsioses are arthropod-borne zoonotic diseases, several of which occur in Australia. This study aimed to assess the exposure levels and risk factors for Rickettsia spp. among Australian wildlife rehabilitators (AWRs) using serology, PCR and a questionnaire. Antibody titres against Spotted Fever Group (SFG), Typhus Group (TG) and Scrub Typhus Group (STG) antigens were determined using an immunofluorescence assay. PCR targeting the gltA gene was performed on DNA extracts from whole blood and serum. Logistic regression was used to identify risk factors associated with seropositivity. Of the 27 (22.1%; 27/122) seropositive participants all were seropositive for SFG, with 5/27 (4.1%) also positive for TG. Of the 27 positive sera, 14.8% (4/27) were further classified as exposure to R. australis, 3.7% (1/27) to R. honei, 3.7% (1/27) to R. felis and 77.8% (21/27) were classified as ‘indeterminate’—most of which (85.7%; 18/21) were indeterminate R. australis/R. honei exposures. Rickettsia DNA was not detected in whole blood or serum. Rehabilitators were more likely to be seropositive if more than one household member rehabilitated wildlife, were older than 50 years or had occupational animal contact. These findings suggest that AWRs are at increased risk of contracting Rickettsia-related illnesses, however the source of the increased seropositivity remains unclear.
Collapse
Affiliation(s)
- Karen O. Mathews
- Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, Camden, NSW 2570, Australia; (D.P.); (J.M.N.); (J.-A.T.); (P.A.S.)
- Correspondence: (K.O.M.); (K.L.B.)
| | - David Phalen
- Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, Camden, NSW 2570, Australia; (D.P.); (J.M.N.); (J.-A.T.); (P.A.S.)
| | - Jacqueline M. Norris
- Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, Camden, NSW 2570, Australia; (D.P.); (J.M.N.); (J.-A.T.); (P.A.S.)
| | - John Stenos
- Australian Rickettsial Reference Laboratory, University Hospital Geelong, Geelong, VIC 3220, Australia; (J.S.); (S.G.); (C.N.)
| | - Jenny-Ann Toribio
- Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, Camden, NSW 2570, Australia; (D.P.); (J.M.N.); (J.-A.T.); (P.A.S.)
| | - Nicholas Wood
- Discipline of Paediatrics and Child Health, Sydney Medical School, The University of Sydney, Camperdown, NSW 2006, Australia;
- National Centre for Immunisation Research and Surveillance, Westmead, NSW 2145, Australia
| | - Stephen Graves
- Australian Rickettsial Reference Laboratory, University Hospital Geelong, Geelong, VIC 3220, Australia; (J.S.); (S.G.); (C.N.)
| | - Paul A. Sheehy
- Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, Camden, NSW 2570, Australia; (D.P.); (J.M.N.); (J.-A.T.); (P.A.S.)
| | - Chelsea Nguyen
- Australian Rickettsial Reference Laboratory, University Hospital Geelong, Geelong, VIC 3220, Australia; (J.S.); (S.G.); (C.N.)
| | - Katrina L. Bosward
- Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, Camden, NSW 2570, Australia; (D.P.); (J.M.N.); (J.-A.T.); (P.A.S.)
- Correspondence: (K.O.M.); (K.L.B.)
| |
Collapse
|
2
|
Willis G, Lodo K, McGregor A, Howes F, Williams S, Veitch M. New and old hotspots for rickettsial spotted fever acquired in Tasmania, 2012-2017. Aust N Z J Public Health 2019; 43:389-394. [PMID: 31268225 DOI: 10.1111/1753-6405.12918] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 03/01/2019] [Accepted: 05/01/2019] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE To describe the epidemiology and clinical characteristics of Tasmania-acquired rickettsial disease notified to the Department of Health in Tasmania from 2012 to 2017 inclusive. METHODS Data on rickettsiosis cases acquired and notified in Tasmania between 1 January 2012 and 31 December 2017 were analysed descriptively. RESULTS Eighteen cases of rickettsial infection notified in Tasmania 2012-17 and likely acquired in the state met one of three case definitions: 12 confirmed (67%), four probable (22%), and two possible (11%). The mean number of cases per year was 3.0 (population rate 0.6 per 100,000 population/year); 60% of cases occurred in November and December. Cases were more commonly older males. Fever, lethargy, and rash were commonly reported symptoms. Thirteen cases were likely acquired on Flinders Island, three around Great Oyster Bay and two in the Midlands. CONCLUSIONS This study extends our knowledge of the epidemiology of rickettsial disease in Tasmania. This is the first account including confirmed cases acquired in the Midlands of Tasmania. Implications for public health: Increased knowledge and awareness of epidemiology of rickettsial infection in Tasmania is essential for timely diagnosis and appropriate treatment. These findings bear wider relevance outside Tasmania because visitors may also be at risk.
Collapse
Affiliation(s)
- Gabriela Willis
- Communicable Disease Prevention Unit, Public Health Services, Department of Health, Tasmania.,National Centre for Epidemiology and Population Health, Australian National University, Australian Capital Territory
| | - Kerryn Lodo
- Communicable Disease Prevention Unit, Public Health Services, Department of Health, Tasmania
| | - Alistair McGregor
- Department of Microbiology and Infectious Diseases, The Royal Hobart Hospital, Tasmania
| | - Faline Howes
- Communicable Disease Prevention Unit, Public Health Services, Department of Health, Tasmania
| | - Stephanie Williams
- National Centre for Epidemiology and Population Health, Australian National University, Australian Capital Territory
| | - Mark Veitch
- Communicable Disease Prevention Unit, Public Health Services, Department of Health, Tasmania
| |
Collapse
|
3
|
Stenos J, Graves SR. Laboratory diagnosis of human infections transmitted by ticks, fleas, mites and lice in Australia. MICROBIOLOGY AUSTRALIA 2018. [DOI: 10.1071/ma18059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
A wide range of human pathogens (viruses, bacteria, protozoa) are transmitted by ticks, fleas, mites and lice worldwide. Some of these infections occur in Australia1, whereas others appear to be absent, although they may occur in returned travellers. The key to diagnosis is two-fold: recognition of the possibility of a vector-borne infection by the treating doctor and confirmation of the diagnosis in a diagnostic, microbiology laboratory. Laboratory diagnostic assays include culture (used rarely), nucleic acid amplification (used increasingly) and serology (used often).
Collapse
|
4
|
Graves SR, Stenos J. Tick-borne infectious diseases in Australia. Med J Aust 2017; 206:320-324. [PMID: 28403767 DOI: 10.5694/mja17.00090] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 02/20/2017] [Indexed: 01/14/2023]
Abstract
Tick bites in Australia can lead to a variety of illnesses in patients. These include infection, allergies, paralysis, autoimmune disease, post-infection fatigue and Australian multisystem disorder. Rickettsial (Rickettsia spp.) infections (Queensland tick typhus, Flinders Island spotted fever and Australian spotted fever) and Q fever (Coxiella burnetii) are the only systemic bacterial infections that are known to be transmitted by tick bites in Australia. Three species of local ticks transmit bacterial infection following a tick bite: the paralysis tick (Ixodes holocyclus) is endemic on the east coast of Australia and causes Queensland tick typhus due to R. australis and Q fever due to C. burnetii; the ornate kangaroo tick (Amblyomma triguttatum) occurs throughout much of northern, central and western Australia and causes Q fever; and the southern reptile tick (Bothriocroton hydrosauri) is found mainly in south-eastern Australia and causes Flinders Island spotted fever due to R. honei. Much about Australian ticks and the medical outcomes following tick bites remains unknown. Further research is required to increase understanding of these areas.
Collapse
Affiliation(s)
| | - John Stenos
- Australian Rickettsial Reference Laboratory, Geelong, VIC
| |
Collapse
|