JCU > Research Portfolio > Prof Scott Ritchie

About

I lead a diverse group of health practitioners and research scientists whose collective goal is to prevent vector-borne disease, especially dengue, in north Queensland.

We have received two NHMRC grants to develop green “Lure and Kill” dengue control programs for North Queensland. I have been a principal investigator in the Eliminate Dengue program funded by the Bill and Melinda Gates Foundation since its inception in 2005. This innovative project utilises the bacterium Wolbachia to prevent the dengue vector Aedes aegypti from transmitting dengue viruses. This partnership has already developed a molecular method to estimate the age of individual mosquitoes, and demonstrated that the parasite can effectively work in the laboratory and in semi-field cages. We are currently evaluating open field releases of Wolbachia-infected Ae. aegypti mosquitoes in Cairns.

I am also involved in new projects studying the potential impact of global warming on dengue in Australia, new pesticides for the control of Ae. aegypti and the development of novel mosquito traps for the detection of pathogens in mosquitoes and other disease vectors.

I was employed as Director, Medical Entomology at the Tropical Regional Services (formerly Tropical Public Health Unit), the preventative health arm of Queensland Health in North Queensland, from 1994-2011. There I have helped develop the world recognised Dengue Fever Management Plan for North Queensland.

Teaching

TM5518: Medical Entomology (Level 5; CNS)

Research Disciplines

Socio-Economic Objectives

Publications

These are the most recent publications associated with this author. To see a detailed profile of all publications stored at JCU, visit ResearchOnline@JCU. Hover over Altmetrics badges to see social impact.

Journal Articles

Buhagiar T, Devine G and Ritchie S (2017) Effects of sublethal exposure to metofluthrin on the fitness of Aedes aegypti in a domestic setting in Cairns, Queensland. Parasites & Vectors, 10 (274). pp. 1-7
Buhagiar T, Devine G and Ritchie S (2017) Metofluthrin: investigations into the use of a volatile spatial pyrethroid in a global spread of dengue, chikungunya and Zika viruses. Parasites & Vectors, 10 (270). pp. 1-11
Johnson B, Hurst T, Quoc H, Unlu I, Freebairn C, Faraji A and Ritchie S (in press) Field comparisons of the Gravid Aedes Trap (GAT) and BG-Sentinel Trap for monitoring Aedes albopictus (Diptera: Culicidae) populations and notes on indoor GAT collections in Vietnam. Journal of Medical Entomology, pp. 1-9
Chambers E, Bossin H, Ritchie S, Russell R and Dobson S (2016) The impact of insecticide-treated cloth targets on the survival of Stegomyia polynesiensis (= Aedes polynesiensis) under laboratory and semi-field conditions in French Polynesia. Medical and Veterinary Entomology, 30 (3). pp. 247-252
Hall-Mendelin S, Pyke A, Moore P, Mackay I, McMahon J, Ritchie S, Taylor C, Moore F and van den Hurk A (2016) Assessment of local mosquito species incriminates Aedes aegypti as the potential vector of zika virus in Australia. PLoS Neglected Tropical Diseases, 10 (9). pp. 1-14
Hancock P, White V, Callahan A, Godfray C, Hoffmann A and Ritchie S (2016) Density-dependent population dynamics in Aedes aegypti slow the spread of wMel Wolbachia. Journal of Applied Ecology, 53. pp. 785-793
Hancock P, White V, Ritchie S, Hoffmann A and Godfray H (2016) Predicting Wolbachia invasion dynamics in Aedes aegypti populations using models of density-dependent demographic traits. BMC Biology, 14 (96). pp. 1-12
Heringer L, Johnson B, Fikrig K, Oliveira B, Silva R, Townsend M, Barrera R, Eiras Á and Ritchie S (2016) Evaluation of alternative killing agents for Aedes aegypti (diptera: culicidae) in the gravid Aedes trap (GAT). Journal of Medical Entomology, 53 (4). pp. 873-879
Johnson B and Ritchie S (2016) The siren's song: exploitation of female flight tones to passively capture male Aedes aegypti (diptera: culicidae). Journal of Medical Entomology, 53 (1). pp. 245-248
Meyer Steiger D, Ritchie S and Laurance S (2016) Mosquito communities and disease risk influenced by land use change and seasonality in the Australian tropics. Parasites & Vectors, 9. pp. 387-400
Meyer Steiger D, Ritchie S and Laurance S (2016) Land use influences mosquito communities and disease risk on remote tropical islands: a case study using a novel sampling technique. American Journal of Tropical Medicine and Hygiene, 94 (2). pp. 314-321
Reiner R, Achee N, Barrera R, Burkot T, Chadee D, Devine G, Endy T, Gubler D, Hombach J, Kleinschmidt I, Lenhart A, Lindsay S, Longini I, Mondy M, Morrison A, Perkins T, Vazquez-Prokopec G, Reiter P, Ritchie S, Smith D, Strickman D and Scott T (2016) Quantifying the epidemiological impact of vector control on dengue. PLoS Neglected Tropical Diseases, 10 (5). pp. 1-11

Current Funding

Current and recent Research Funding to JCU is shown by funding source and project.

United States Department of Defence - Deployed war fighter protection research program

Deployment of optimal-dose, volatile pyrethroids for the prevention of biting and disease transmission by insects

Indicative Funding: $243,972 over 3 years (administered by QIMR)
Summary: We will measure the efficacy of volatile synthetic pyrethroid insecticides against several mosquito vectors of disease, including the dengue mosquito Aedes aegypti. Trials will be conducted in the lab and in room situations to simulate real world situations.
Investigators: Scott Ritchie and Gregor Devine (College of Public Health, Medical & Vet Sciences and Queensland Institute of Medical Research)
Keywords: Dengue; Aedes aegypti mosquitoes; insecticide

Menzies School of Health Research - Ext_Source: NHMRC NATDCRP Hot North Pilot

Can mosquito excreta be used to enhance detection of Australian vector-borne diseases?

Indicative Funding: $31,500 (administered by Menzies School of Health Research)
Summary: Testing for presence of arboviruses usually involves capturing wild mosquitoes and complicated laboratory analyses. These are not only time- and labour-intensive but also costly. Virus detection can be made from saliva however, mosquitoes only expel very small amounts which makes detection difficult. We are proposing to use their excreta instead as it is produced in greater quantities than saliva, and shows higher sensitivity in virus detection. In order to explore this proposal we need to know where and when mosquitoes discharge their excreta in the traps. The discharge of excreta could be dependent on a variety of factors such as temperature, time after last meal or time of day/night, type of trap; it may also be species-dependent or it could just be random. These factors need to be examined to ensure maximum collection of excreta. The results will lead to the modification and optimization of existing traps.
Investigators: Scott Ritchie, Dagmar Meyer Steiger, Ana Ramirez Lopez, Andrew van den Hurk and Nina Kurucz (College of Public Health, Medical & Vet Sciences, Australian Institute of Tropical Health & Medicine, Queensland Health and Department of Health (NT))
Keywords: Arbovirus; Mosquito; Encephalitis

US Agency for International Development - USAID

Zika: A fast new intervention and an innovative method of evaluation

Indicative Funding: $100,135 (administered by Queensland Institute of Medical Research Berghofer)
Summary: We will provide access to the Mosquito Research Facility for testing of rapid methods to control Zika vector Ae. aegypti. This will include new near IR methods to age mosquitoes within our semi-field cages. We will study the impact of vapour active insecticides and influence of Wolbachia infection on the method.
Investigators: Scott Ritchie, Chris Paton and Gregor Devine (College of Public Health, Medical & Vet Sciences, University of Oxford and QIMR Berghofer Medical Research Institute)
Keywords: Dengue; Zika; Aedes aegypti

NHMRC - Project Grant

Release the sterile males: A new direction for mosquito population control

Indicative Funding: $150,000 over 2 years (administered by CSIRO)
Summary: Using RNA interference (RNAi) technology, we can expose insects to double-stranded RNA (dsRNA) during larval development in a manner which will shut down sperm production in fit, adult males and either stop females emerging or transform female larvae into sterile male phenotypes. This Sterile Insect Technique (SIT) approach would simultaneously remove the requirement for female/male separation and so enhance the efficiency of release programmes. We will rear and release dengue vectors Aedes aegypti that have been in colony and have never been exposed to dengue or other arboviruses. These will be reared in the presence of dsRNA to sterilise the males; females (ca. 96%) will be killed by this method. These sterile males will then be released into a semi-field cage (JCU Mosquito Research Facility) containing 100-500 uninfected Ae. aegypti. The sterile males should mate with females resulting in a crash in the population through time, providing a proof of concept for the method.
Investigators: Nigel Beebe, Scott Ritchie, Steve Whyard and Paul DeBarro (Commonwealth Scientific & Industrial Research Organisation, College of Public Health, Medical & Vet Sciences and The University of Manitoba)

NHMRC - Research Fellowship

Senior Research Fellowship A

Indicative Funding: $590,785 over 5 years
Summary: North Queensland and the adjacent tropics are subject to incursions of exotic mosquitoes and the diseases they vector, especially dengue. I lead a diverse group of health researchers at JCU that develop strategies to prevent vector-borne disease in North Queensland that have global application. I am also employed as a consultant medical entomologies with Queensland Health, and thus am able to strategically apply my research on vector-borne diseases to end users.
Investigators: Scott Ritchie (College of Public Health and Medical & Vet Sciences)
Keywords: Arbovirus; Arbovirus diseases; Mosquito -borne disease; Dengue; Encephalitis

Western Australia Department of Health - Funding Initiative for Mosquito Management in Western Australia (FIMMWA)

Efficacy of sentinel passive traps (SMACKs) and FTA cards for arbovirus surveillance in Western Australia and the Northern Territory

Indicative Funding: $51,135 over 2 years
Summary: Mosquito-borne viruses (e.g. Ross River virus, Murray Valley encephalitis virus and Kunjin virus) cause human disease in Western Australia. Current surveillance relies on sentinel chicken flocks for antibody detection and mosquito collections for virus detection. Recently developed Sentinel Mosquito Arbovirus Capture Kits (SMACK) consisting of passive traps baited with CO2 and honey-baited FTA nucleic acid preservation cards to directly monitor these viruses in remote areas. To confirm that the FTA card system is effective we will compare virus detection rates in SMACKs run parallel with sentinel chicken flocks in remote WA and the NT areas. A full costing will also be conducted.
Investigators: Scott Ritchie and John Smith in collaboration with Brian Johnson, Cheryl Johansen, Linda Selvey, Michael Lindsay, David Smith and Nina Kurucz (College of Public Health, Medical & Vet Sciences, The University of Western Australia, PathWest Laboratory Medicine, Curtin University of Technology, WA Department of Health and Department of Health (NT))
Keywords: Arbovirus surveillance; Ross River Virus; Murray Valley Encephalitis; Sentinel Animals; West Nile Virus (Kunjin subtype)

Supervision

Advisory Accreditation: I can be on your Advisory Panel as a Primary or Secondary Advisor.

These Higher Degree Research projects are either current or by students who have completed their studies within the past 5 years at JCU. Linked titles show theses available within ResearchOnline@JCU.

Current

Larval density and adult fitness in Anopheles farauti: Towards understanding how larval control may impact transmission by adults (PhD , Secondary Advisor)
When World's Collide: Where and When Anophelines and Humans Interact Impacts Malaria Transmission (PhD , Secondary Advisor)
Using Mosquito Excreta to Enhance Mosquito-Borne Disease Surveillance (PhD , Primary Advisor)
Survey of Dengue Fever Vectors and its Serotype Viruses in Solomon Islands (PhD , Primary Advisor)

Completed

Mosquito (Diptera: Culicidae) communities across land uses in tropical Australia (2016, PhD , Secondary Advisor)
The biodegradable lethal ovitrap as a control method for dengue in Cairns, North Queensland with a focus on post four week deployment (2013, Masters , Primary Advisor)

Collaboration

The map shows research collaborations by institution from the past 7 years.
Note: Map points are indicative of the countries or states that institutions are associated with.