Australian Army Malaria Institute

Brisbane, Australia

Australian Army Malaria Institute

Brisbane, Australia
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Russell T.L.,James Cook University | Beebe N.W.,University of Queensland | Beebe N.W.,CSIRO | Cooper R.D.,Australian Army Malaria Institute | And 2 more authors.
Malaria Journal | Year: 2013

Background: The ultimate long-term goal of malaria eradication was recently placed back onto the global health agenda. When planning for this goal, it is important to remember why the original Global Malaria Eradication Programme (GMEP), conducted with DDT-based indoor residual spraying (IRS), did not achieve its goals. One of the technical reasons for the failure to eliminate malaria was over reliance on a single intervention and subsequently the mosquito vectors developed behavioural resistance so that they did not come into physical contact with the insecticide. Hypothesis and how to test it. Currently, there remains a monolithic reliance on indoor vector control. It is hypothesized that an outcome of long-term, widespread control is that vector populations will change over time, either in the form of physiological resistance, changes in the relative species composition or behavioural resistance. The potential for, and consequences of, behavioural resistance was explored by reviewing the literature regarding vector behaviour in the southwest Pacific. Discussion. Here, two of the primary vectors that were highly endophagic, Anopheles punctulatus and Anopheles koliensis, virtually disappeared from large areas where DDT was sprayed. However, high levels of transmission have been maintained by Anopheles farauti, which altered its behaviour to blood-feed early in the evening and outdoors and, thereby, avoiding exposure to the insecticides used in IRS. This example indicates that the efficacy of programmes relying on indoor vector control (IRS and long-lasting, insecticide-treated nets [LLINs]) will be significantly reduced if the vectors change their behaviour to avoid entering houses. Conclusions: Behavioural resistance is less frequently seen compared with physiological resistance (where the mosquito contacts the insecticide but is not killed), but is potentially more challenging to control programmes because the intervention effectiveness cannot be restored by rotating the insecticide to one with a different mode of action. The scientific community needs to urgently develop systematic methods for monitoring behavioural resistance and then to work in collaboration with vector control programmes to implement monitoring in sentinel sites. In situations where behavioural resistance is detected, there will be a need to target other bionomic vulnerabilities that may exist in the larval stages, during mating, sugar feeding or another aspect of the life cycle of the vector to continue the drive towards elimination. © 2013 Russell et al.; licensee BioMed Central Ltd.


Shanks G.D.,Australian Army Malaria Institute | Brundage J.F.,Armed Forces Health Surveillance Center
American Journal of Epidemiology | Year: 2014

Until the mid-20th century, mortality rates were often very high during measles epidemics, particularly among previously isolated populations (e.g., islanders), refugees/internees who were forcibly crowded into camps, and military recruits. Searching for insights regarding measles mortality rates, we reviewed historical records of measles epidemics on the Polynesian island of Rotuma (in 1911), in Boer War concentration camps (in 1900-1902), and in US Army mobilization camps during the First World War (in 1917-1918). Records classified measles deaths by date and clinical causes; by demographic characteristics, family relationships (for Rotuma islanders and Boer camp internees), and prior residences; and by camp (for Boer internees and US Army recruits). During the Rotuman and Boer War epidemics, measles-related mortality rates were high (up to 40%); however, mortality rates differed more than 10-fold across camps/districts, even though conditions were similar. During measles epidemics, most deaths among camp internees/military recruits were due to secondary bacterial pneumonias; in contrast, most deaths among Rotuman islanders were due to gastrointestinal complications. The clinical expressions, courses, and outcomes of measles during first-contact epidemics differ from those during camp epidemics. The degree of isolation from respiratory pathogens other than measles may significantly determine measles-related mortality risk. © The Author 2013.


Shanks G.D.,Australian Army Malaria Institute | Shanks G.D.,University of Queensland | Waller M.,University of Queensland | MacKenzie A.,University of Queensland | Brundage J.F.,Armed Forces Health Surveillance Center
The Lancet Infectious Diseases | Year: 2011

In 1918, two waves of epidemic influenza arose with very different clinical phenotypes. During the first wave, infection rates were high but mortality was low. During the second wave, high numbers of deaths occurred and mortality differed 30-100 times among seemingly similar groups of affected adults, but the reason for this variation is unclear. In 1918, the crews of most warships and some island populations were affected by influenza during both waves of infection and had no or very few deaths during the second wave. However, some warships and island populations were not affected during the first wave of infection and had high mortality during the second wave. These findings suggest that infection during the first wave protected against death, but not infection, during the second wave. If so, the two waves of infection were probably caused by antigenically distinct influenza viruses-not by one virus that suddenly increased in pathogenicity between the first and second waves. These findings are relevant to modern concerns that the 2009 influenza A H1N1 virus could suddenly increase in lethality. © 2011 Elsevier Ltd.


Shanks G.D.,Australian Army Malaria Institute | Shanks G.D.,University of Queensland | Shanks G.D.,University of Oxford | White N.J.,Mahidol University | White N.J.,Churchill Hospital
The Lancet Infectious Diseases | Year: 2013

The periodicity of vivax malaria relapses may be explained by the activation of latent hypnozoites acquired from a previous malarial infection. The activation stimulus could be the febrile illness associated with acute malaria or a different febrile infection. We review historical records to examine the association between relapses of Plasmodium vivax and febrile infectious diseases. In data from British soldiers in Palestine, epidemic falciparum malaria triggered a smaller epidemic of P vivax relapses only in those who had been extensively exposed to malaria previously. Relapses did not follow pandemic influenza infection. Evidence from three simultaneous typhoid and malaria epidemics suggest that typhoid fever might activate P vivax hypnozoites. Some data lend support to the notion that vivax malaria relapse followed febrile illness caused by relapsing fever, trench fever, epidemic typhus, and Malta fever (brucellosis). These observations suggest that systemic parasitic and bacterial infections, but not viral infections, can activate P vivax hypnozoites. Specific components of the host's acute febrile inflammatory response, and not fever alone, are probably important factors in the provocation of a relapse of vivax malaria. © 2013 Elsevier Ltd.


Shanks G.D.,Australian Army Malaria Institute | Shanks G.D.,University of Queensland | Shanks G.D.,University of Oxford
The Lancet | Year: 2014

World War 1 was a key transition point towards scientific medicine. Medical officers incorporated Louis Pasteur's discoveries into their understanding of microorganisms as the cause of infectious diseases, which were therefore susceptible to rational control and treatment measures even in the pre-antibiotic era. Typhoid vaccination led to the successful evasion of the disastrous epidemics of previous wars. The incidence of tetanus was probably decreased by giving millions of doses of horse antitoxin to wounded soldiers. Quinine treated but could not control malaria; its use required mass compulsion. Tuberculosis was not a great military problem during World War 1, although mortality in civilian populations increased substantially. Treatment of sexually transmitted infections remained a matter of aversive conditioning, with invasive antiseptics used in the absence of antibiotics. Pandemic influenza in 1918-19 killed more people than died during the entire war, showing how much remained beyond the capability of the scientists and doctors who fought infectious diseases during World War 1. © 2014 Elsevier Ltd.


Frances S.P.,Australian Army Malaria Institute
Journal of the American Mosquito Control Association | Year: 2013

Field efficacy trials comparing 2 formulations of deet against mosquitoes in Redcliffe, Queensland, Australia were conducted in February 2009. A formulation containing 35% deet in a gel (Australian Defence Force deet) provided >95% protection for 3 h, while a formulation containing 40% deet in ethanol (Bushman) in a spray applicator provided >95% for 6 h. A user acceptability study showed that 82% of soldiers using the Bushman formulation during contingency operations for 14-28 days in Timor-Leste would recommend this formulation to others and believed that the formulation provided protection against mosquitoes. © 2013 by The American Mosquito Control Association, Inc.


Shanks G.D.,Australian Army Malaria Institute
Journal of Military and Veterans' Health | Year: 2016

As the Army Malaria Institute entered its fifth decade, its research mission expanded and matured. Five research departments were engaged in assessing a variety of malaria drugs, molecular biology, field, clinical and diagnostic studies while arbovirus vaccines and molecular epidemiology topics were studied. Internal and external reviews of the Army Malaria Institute (AMI) were conducted indicating that AMI should remain within the Joint Health Command and eventually change its name to better reflect its role within the entire Australian Defence Force and with infectious diseases beyond malaria. AMI's deployment capability is intended to be emphasised by the evolution of a separate identifiable unit involving the uniformed members. How AMI should manage its quasi-academic status as well as external research funds has not been determined yet. As AMI's Fiftieth Anniversary approaches in mid-2016, it is clear that the on-going threat of infectious diseases to the ADF will mean that the Institute will continue to evolve its structure and functions into the future. © 2016, Australian Military Medicine Association. All rights reserved.


Elmes N.J.,Australian Army Malaria Institute
International Health | Year: 2010

We report here a retrospective analysis of all malaria cases in military personnel reported to the Australian Defence Force (ADF) Central Malaria Register from 1998 to 2007. A total of 637 cases of malaria were notified affecting 487 individuals. Of these 85.9% (547) were infected with Plasmodium vivax malaria and 10.2% (65) with P. falciparum malaria. The majority of cases were from Timor Leste (78.5%, 501/637). Malaria attack rates of 0.9% (369/40 571), 1.1% (52/4776) and 0.4% (20/5345) were seen in Timor Leste, Bougainville and the Solomon Islands, respectively. The median period following departure from a malarious country to presentation of P. falciparum was 17 d (range 1-47 d) and for a primary presentation of P. vivax malaria was 86 d (range 1-505 d). Increasing the dose of primaquine from 22.5 mg daily to 30 mg daily for 14 d for radical cure of P. vivax malaria reduced the failure rate from 46.6% (35/75) to 9.4% (17/181) in subjects returning from Timor Leste. Malaria remains a serious problem for ADF soldiers deploying to malarious areas, particularly the incidence of relapsing vivax malaria and the tolerance of these vivax strains to primaquine. Crown Copyright © 2010.


BACKGROUND: Plasmodium falciparum and Plasmodium vivax are endemic in Vanuatu and the Solomon Islands. While both countries have introduced artemether-lumefantrine (AL) as first-line therapy for both P. falciparum and P. vivax since 2008, chloroquine and sulphadoxine-pyrimethamine (SP) were used as first-line therapy for many years prior to the introduction of AL. Limited data are available on the extent of SP resistance at the time of policy change.METHODS: Blood spots were obtained from epidemiological surveys conducted on Tanna Island, Tafea Province, Vanuatu and Temotu Province, Solomon Islands in 2008. Additional samples from Malaita Province, Solomon Islands were collected as part of an AL therapeutic efficacy study conducted in 2008. Plasmodium vivax and P. falciparum dhfr and dhps genes were sequenced to detect nucleotide polymorphisms.RESULTS: All P. falciparum samples analysed (n=114) possessed a double mutant pfdhfr allele (C59R/S108N). Additionally, mutation A437G in pfhdps was detected in a small number of samples 2/13, 1/17 and 3/26 from Tanna Island, Vanuatu and Temotu and Malaita Provinces Solomon Islands respectively. Mutations were also common in pvdhfr from Tanna Island, Vanuatu, where 33/51 parasites carried the double amino acid substitution S58R/S117N, while in Temotu and Malaita Provinces, Solomon Islands 32/40 and 39/46 isolates carried the quadruple amino acid substitution F57L/S58R/T61M/S117T in DHFR respectively. No mutations in pvdhps (n=108) were detected in these three island groups.CONCLUSION: Prior to the introduction of AL, there was a moderate level of SP resistance in the P. falciparum population that may cause SP treatment failure in young children. Of the P. vivax isolates, a majority of Solomon Islands isolates carried quadruple mutant pvdhfr alleles while a majority of Vanuatu isolates carried double mutant pvdhfr alleles. This suggests a higher level of SP resistance in the P. vivax population in Solomon Islands compared to the sympatric P. falciparum population and there is a higher level of SP resistance in P. vivax parasites from Solomon Islands than Vanuatu. This study demonstrates that the change of treatment policy in these countries from SP to ACT was timely. The information also provides a baseline for future monitoring.


BACKGROUND: Chloroquine (CQ), alone or in combination with sulphadoxine-pyrimethamine, was widely used for the treatment of Plasmodium falciparum and Plasmodium vivax for several decades in both Vanuatu and Solomon Islands prior to the introduction of artemether-lumefantrine (AL) in 2008. However, the effect of chloroquine selection on parasite population, which may affect the efficacy of lumefantrine or other partner drugs of artemisinin, has not been well assessed. This study aims to provide baseline data on molecular markers (pfcrt and pfmdr1), along with the origins of pfcrt, prior to the introduction of AL.METHODS: Blood spots were obtained from epidemiological surveys conducted on Tanna Island, Tafea Province, Vanuatu and Temotu Province, Solomon Islands in 2008. Additional samples from Malaita Province, Solomon Islands were collected as part of an artemether-lumefantrine efficacy study in 2008. Plasmodium falciparum pfcrt and pfmdr1 genes were examined for polymorphisms. Microsatellite markers flanking pfcrt were also examined to ascertain origins of CQ resistance.RESULTS: Pfcrt analysis revealed 100% of parasites from Tafea Province, Vanuatu and Malaita Province, Solomon Islands and 98% of parasites from Temotu Province, Solomon Islands carried the K76T polymorphism that confers CQ resistance. Comparison of pfcrt allelic patterns and microsatellite markers flanking pfcrt revealed six haplotypes with more than 70% of isolates possessing haplotypes very similar to those observed in Papua New Guinea. The dominant (98.5%) pfmdr1 allele across all island groups was YYCND.CONCLUSIONS: Prior to the introduction of AL in the Solomon Islands and Vanuatu, P. falciparum isolates possessed point mutations known to confer CQ resistance and possibly associated with a decreased susceptibility to quinine and halofantrine, but an increased susceptibility to artemisinin and lumefantrine. Overall, pfcrt allelic types and the flanking microsatellite markers exhibited similarities to those of Papua New Guinea, suggesting these parasites share a common ancestry. The current use of AL for both P. falciparum and P. vivax infections will enable changes in these markers, in the absence of CQ pressure, to be monitored.

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