Volume 164 Issue 6

AbstractObjective: To assess the effectiveness of the flashlamp-pumped pulsed dye laser in the treatment of port-wine stains. Design: A retrospective review of medical records and patients. Setting: Royal Perth Hospital (a tertiary referral hospital), August 1989 to December 1992. Subjects: 186 consecutive patients with port-wine stains treated with a flashlamp-pumped pulsed dye laser. Outcome measures: Degree of lesion fading; adverse reactions. Results: Of 131 patients who completed treatment, 78% had better than 50% fading of the lesion and only 9% had less than 25% fading. An average 3.4 treatments were needed to achieve more than 50% fading. The response was better in children than in adults, although the difference was not significant. Anaesthesia was needed for 44% of patients. Pigmentary change (usually transient) occurred in 6.1% of patients and permanent and significant adverse effects in only 4.6%. Conclusion: This study confirms the efficacy of the flashlamp-pumped pulsed dye laser in the treatment of port-wine stains in children and adults. Early treatment of port-wine stains should be encouraged to reduce the physical and psychological morbidity of disfiguring lesions. IntroductionPort-wine stains (now termed capillary malformations) are congenital vascular malformations characterised by ectatic vessels within the cutaneous superficial vascular plexus.1 They affect 0.3% of children at birth, with an equal sex distribution.2 Most port-wine stains are found on the head and neck, with 85% occurring in a unilateral, dermatomal distribution.3 Their natural history is to progress from a pink, macular lesion at birth to a dark red (or even purple), nodular, proportionately larger lesion in adulthood.1,4 Cosmetic disfigurement can cause considerable psychological morbidity, and be socially disadvantageous.5,6 Hypertrophic, nodular lesions may bleed, either spontaneously or after trauma, encroach on essential facial structures or even develop into pyogenic granulomas.7 All port-wine stains should be treated, preferably early in life, to prevent or reduce the potential physical and psychological complications. Before the development of laser technology, treatment for port-wine stains was often unsatisfactory.8 Earlier lasers, including ruby, carbon dioxide and argon lasers, improved the lesions in most patients, but, as they were non-selective in their effects on tissue, the frequency of side effects, such as scarring and pigmentary changes, was unacceptably high.9 The flashlamp-pumped pulsed dye laser (PDL) was the first laser to be based on selective photothermolysis;10 it produces vascular- specific damage without affecting surrounding dermal structures or the epidermis.11-13 Studies have confirmed its effectiveness in the treatment of port-wine stains in adults, children and infants, with an extraordinarily low incidence of side effects.14-19 The PDL is now regarded as the first-line treatment for port-wine stains whenever possible.8,9,20-22 In Australia, the PDL has been in use since the late 1980s for the treatment of cutaneous vascular lesions, especially port-wine stains. However, no Australian study of its effects has been published. Therefore, we undertook a retrospective clinical review of all patients with port-wine stains treated with PDL at Royal Perth Hospital between August 1989 and December 1992. MethodsThe study was a retrospective review of patient medical records. If response to treatment was not recorded, attempts were made to review the patient between January and December 1993. PatientsAll patients (adult and paediatric) with a port-wine stain treated with PDL at Royal Perth Hospital between August 1989 and December 1992 were eligible. Patients attended outpatient clinics, where the site and size of the port-wine stain and demographic data were recorded and the treatment procedure and its risks and benefits were explained. Patients were photographed before treatment by a professional photographer in a studio dedicated to medical photography, with efforts to use the same magnification, lighting and exposure. Laser and techniqueA flashlamp-pumped pulsed dye laser (Candela SPTL-1, Candela Corp, Wayland, Mass, United States) was used. It emitted yellow light at a wavelength of 585 nm, with a pulse duration of 450 µs and a 3 s pause between pulses. The laser beam was transmitted down a 1 mm fibre by a planoconvex lens and focused as a 5 mm spot beam. Energy densities were measured by an energy meter (Ophir, Jerusalem, Israel), calibrated to 10% accuracy. Both the physicians and the patients eyes were protected from laser light during treatment. Some patients had a small initial test patch treated, depending on patient anxiety and time of presentation (before 1991, most had a patch test). Otherwise, the entire lesion was treated at once, unless it involved a large surface area (> 100 cm2). Treatments were repeated at intervals of 23 months. The energy density used varied with the age of the patient and colour, nodularity and location of the lesion and was adjusted according to the degree of purpura produced and the patients response to the previous treatment. Pulses were overlapped by a maximum of 10% across the affected area. The anaesthetic varied according to the site and area to be treated and the level of patient cooperation. EMLA cream (eutectic mixture of 2.5% lignocaine and 2.5% prilocaine cream, Astra Pharmaceuticals, North Ryde, NSW) was used for topical anaesthesia, applied under occlusion for 60120 minutes before treatment. Local anaesthesia involved an injection of 1% lignocaine, either locally or as a regional nerve block. General anaesthesia was given to children who had extensive lesions or were uncooperative with topical or local anaesthesia. The treated area developed purpura within a few minutes, usually persisting for 710 days. No immediate postoperative care was necessary, except for an occasional ice pack to reduce oedema in those with large treatment areas. Postoperative instructions were to protect the area from trauma, avoid excessive exposure to sunlight and use a topical antiseptic cream for any scaling or crusting. Treatment evaluationEach port-wine stain was evaluated, either before the next treatment or 34 months after the final treatment. Lesional lightening was assessed as the percentage reduction in colour compared with the pretreatment photo (fading < 25%, poor; 25% to 50%, fair; > 50% to 75%, good; and > 75%, excellent) (Figures 1-4). Adverse effects, such as scarring and textural or pigmentary changes, were also noted. All patients were individually assessed by one or both investigators. The endpoint of treatment was assessed clinically. Data analysisData were analysed with the Statistical Analysis Systems software package.23 The chi-squared statistic was used to assess the difference in response between age groups. ResultsThere were 186 patients treated by PDL: 131 completed treatment (55 either did not complete treatment or were having ongoing treatment). Patients were either Caucasian or Asian and aged 8 months to 66 years (mean, 25.6 years). There were 59 males (32%) and 127 females (68%). Most of the treated lesions were present from birth (97%). Acquired lesions appeared most commonly between the ages of six and 12. Most lesions were on the face and neck (87%), with the rest distributed unilaterally on the arms (4%), legs (5%), back (2%) and chest (2%). The size of treated lesions ranged from 1 cm2 to 280 cm2 (mean, 42 cm2). All responded to energy fluences between 5 and 10 joules/cm2(mean, 6.7 joules/cm2). Sixty-two per cent of the patients had a patch test before treatment. Anaesthesia was used for 44% of patients (general anaesthesia by 20%, topical by 19% and local or regional block by 5%). Responses of patients who completed treatment are shown in the Box. A good-to-excellent response was achieved in 78% and a poor response in only 9%. An average 3.4 treatments per lesion were required to achieve a good-to-excellent response. Adverse side effects occurred in 11% of patients who completed treatment; all had some fading of the lesion. The most common adverse effect was pigmentary change (6.1%), which was usually transient and resolved in 23 months. Only 4.6% had significant permanent adverse effects; two had scarring (in both the port-wine stain was on the face and neck region). More children than adults had a good or excellent response, but the difference was not significant when compared with a 2 x 2 contingency table and chi-squared test (r = 0.60). Similarly, fewer children than adults had a poor response. DiscussionOur results compare favourably with those of other studies. A good-to-excellent response (more than 50% fading) was obtained in 78% of our patients (including both adults and children, with lesions on sites including the trunk and lower limbs), with an average 3.4 treatments required. Others have found more than 50% fading in 73%-95% of patients after 2.4-2.8 treatments.14-17,24,25 Response to treatment varies between sites: the periorbital area, temple, lateral aspect of the cheek, neck and chin have been observed to be more responsive18,25 and the centrofacial area and lower leg to be less responsive.18,19 We found that a poor response was more common in adults than in children (although the difference was not significant), possibly because port-wine stains become progressively hypertrophied and nodular in adults. We found a higher rate of adverse effects (11%) than in other studies. The most common (usually transient) adverse effect was pigmentary change (increase or decrease), possibly because of excessive sunlight exposure after treatment. This transient change may not have been recorded in other studies; when it was excluded from our figures, the rate of adverse reactions was reduced to less than 5%, which is comparable with that found in other studies. Scarring was seen in two of our patients, with lesions on the face and neck, where damage to dermal structures with fibrosis occurs when excessive energy fluence is used. A low energy fluence should be used initially when treating port-wine stains on the neck and anterior chest. The PDL is the first laser specifically designed for cutaneous vascular malformations. It is based on the theory of selective photothermolysis, which predicts selective destruction of blood vessels without damage to the surrounding tissues.10 Laser light emitted by the PDL is absorbed by oxyhaemoglobin in the dilated vessels of the lesion, producing agglutination of erythrocytes, thrombus formation and eventual destruction of the vessels.11 They are replaced by non-dilated superficial dermal blood vessels with a normal appearance.12 A recent comparison of PDL and the copper vapour laser showed that PDL produced significantly better fading of port-wine stains.22 The characteristics and degree of pain associated with PDL treatment have been well described.26 Initially, there is a sharp stinging pain, very similar to the snap of a rubber band against the skin. Accompanying this is a second distinct heat sensation that can be at least as unpleasant as the initial sting. Pain rapidly subsides but seems to build up if successive pulses are used for a moderately sized lesion. Our current practice is to give general anaesthesia to all children from four weeks of age, until they are able to co-operate with topical or local anaesthesia, usually at eight to 10 years. Young children undergoing multiple painful treatments with inadequate anaesthesia under restraint may develop phobic responses. Furthermore, a struggling child may compromise the clinicians ability to perform the procedure optimally. In conclusion, this study supports the contention that all port-wine stains should be treated with PDL, as it has a high therapeutic index with a low incidence of adverse effects. Patients should preferably be treated in infancy or childhood, under general anaesthesia, to minimise the potential psychological morbidity of disfiguring lesions. In addition, the response to treatment seems better in children than in adults, although the difference was not significant, possibly because of the relatively small sample size. Laser treatment of port-wine stains should no longer be considered just cosmetic, but a medical necessity for a problem that can cause psychological and physical morbidity. References Mulliken JB. Capillary (port-wine) and other telangiectatic stains. In: Mulliken JB, Young AE, editors. Vascular birthmarks -- haemangiomas and malformations. Philadelphia: W B Saunders, 1988: 179-195. Jacobs AH, Walton RG. The incidence of birthmarks in the neonate. Pediatrics 1976; 58: 218-222. Tallman B, Tan OT, Morelli JG, et al. Location of port-wine stains and the likelihood of ophthalmic and/or central nervous system complications. Pediatrics 1991; 87: 323-327. Barsky SH, Rosen S, Geer DE, Noe JM. The nature and evolution of port-wine stains: a computer-assisted study. J Invest Dermatol 1980; 74: 154-157. Lanigan SW, Cotterill JA. Psychological disabilities amongst patients with port wine stains. Br J Dermatol 1989; 121: 209-215. Pickering JW, Butler PH, Ring BJ, Walker EP. Copper vapour laser treatment of port wine stains: a patient questionnaire. Lasers Med Sci 1990; 5: 43-49. Geronemus RG, Ashinoff R. The medical necessity of evaluation and treatment of port-wine stains. J Dermatol Surg Oncol 1991; 17: 76-79. Wheeland RG. Treatment of port-wine stains for the 1990s. J Dermatol Surg Oncol 1993; 19: 348-356. Van Gemert MJ, Carruth JA, Shakespeare PG. Laser treatment of the port-wine stains. BMJ 1993; 306: 4-5. Anderson RR, Parrish JA. Selective photothermolysis: precise microsurgery by selective absorption of pulsed radiation. Science 1983; 220: 524-527. Nakagawa H, Tan OT, Parrish JA. Ultrastructural changes in human skin after exposure to a pulsed laser. J Invest Dermatol 1985; 84: 396-400. Morelli JG, Tan OT, Garden J, et al. Tunable dye laser (577 nm) treatment of port wine stains. Lasers Surg Med 1986; 6: 94-96. Tan OT, Morrison P, Kurban AK. 585 nm for the treatment of port-wine stains. Plast Reconstr Surg 1990; 86: 1112-1117. Garden JM, Polla LL, Tan OT. The treatment of port-wine stains by the pulsed dye laser: analysis of pulse duration and long-term therapy. Arch Dermatol 1988; 124: 889-896. Tan OT, Sherwood K, Gilchrest BA. Treatment of children with port-wine stains using the flashlamp-pulsed tunable dye laser. N Engl J Med 1989; 320: 416-421. Reyes BA, Geronemus RG. Treatment of port-wine stains during childhood with the flashlamp-pumped pulsed dye laser. J Am Acad Dermatol 1990; 23: 1142-1148. Ashinoff R, Geronemus RG. Flashlamp-pumped pulsed dye laser for port-wine stains in infancy: earlier versus later treatment. J Am Acad Dermatol 1991; 24: 467-472. Renfro L, Geronemus RG. Anatomical differences of port-wine stains in response to treatment with the pulsed dye laser. Arch Dermatol 1993; 129: 182-188. Garden JM, Bakus AD. Clinical efficacy of pulsed dye laser in the treatment of vascular lesions. J Dermatol Surg Oncol 1993; 19: 321-326. Geronemus RG. Pulsed dye laser treatment of vascular lesions for children. J Dermatol Surg Oncol 1993; 19: 303-310. Hruza GJ, Geronemus RG, Dover JS, Arndt KA. Lasers in dermatology Ñ 1993. Arch Dermatol 1993; 129: 1026-1035. Sheehan-Dare RA, Cotterill JA. Copper vapour laser (578 nm) and flashlamp-pumped pulsed tunable dye laser (585 nm) treatment of port-wine stains: results of a comparative study using test sites. Br J Dermatol 1994; 130: 478-482. Statistical Analysis Systems [computer program], version 6.08. Cary (NC): SAS Institute Inc, 1994. Goldman MP, Fitzpatrick RE, Ruiz-Esparza J. Treatment of port-wine stains (capillary malformation) with the flashlamp-pumped pulsed dye laser. J Pediatr 1993; 122: 71-77. Holy A, Geronemus RG. Treatment of periorbital port-wine stains with the flashlamp-pumped pulsed dye laser. Arch Ophthalmol 1992; 110: 793-797. Rabinowitz LG, Esterly NB, Frieden IJ, et al. Anesthesia and/or sedation for pulsed dye laser therapy. Pediatr Dermatol 1992; 9: 132-153. Authors detailsDepartment of Dermatology, Royal Perth Hospital, Perth, WA. Ernest Tan, MB BS, Dermatology Registrar; Carl Vinciullo, FACD, Visiting Dermatologist. No reprints will be available. Correspondence: Dr C Vinciullo, Department of Dermatology, Royal Perth Hospital, Wellington Street, WA 6000. E-mail: carlATdermlaser.com.au

Ernest Tan · Carl Vinciullo

Although endemic malaria was eradicated from Australia by 1981, the vectors remain and transmission from imported cases still occurs. Climate modelling shows that global warming will enlarge the potential range of the main vector, Anopheles farauti sensu stricto; by the year 2030 it could extend along the Queensland coast to Gladstone, 800 km south of its present limit. Vigilance and a dispassionate assessment of risk are needed to meet this challenge. IntroductionAustralia has long been under threat from malaria and this has led many to predict, from early times, that without vigilance there will be outbreaks.1 Climate change due to the enhanced greenhouse effect is expected to extend vector ranges2and potentially expand the threat. It is timely to review the epidemiology of malaria in Australia and explore its future with climate change. Although malaria transmission has occurred widely in Australia,3 the disease was eradicated by 1981.4 Imported cases (acquired outside Australia) and introduced cases (derived from imported cases), which still occur, do not invalidate this "free from endemic malaria" status; malaria is considered endemic only if parasitaemia arises from introduced cases or other endemic infections.5 However, Australia remains vulnerable to malaria transmission, as the vectors have not been eradicated and hundreds of cases are imported annually. Natural infections have been found in Anopheles hilli and An. farauti6sensu lato (s.l.) (a group of three morphologically indistinguishable species,7,8 found in northern Australia,6 which have not yet been given formal names). In southern Australia, An. annulipes s.l. is the putative vector.3An. amictus, An. bancroftii and An. stigmaticus are susceptible to malaria in the laboratory6 and may play a role in the field. Nevertheless, experience since the 1900s strongly supports the hypothesis that An. farauti s.l. is the most important vector. Receptivity to malariaFord9 delineated the potentially malarious area of Australia, within which "implantation" may occur, as extending south to latitude 19oS in Queensland, to about 17oS in the Northern Territory and to about 19oS in Western Australia, except for a non-receptive coastal strip including Broome at 18oS. Although transmission had occurred widely outside this area, Ford thought conditions elsewhere did not favour maintenance of transmission. The area north of 19oS, largely coinciding with the range of An. farauti s.l.,6 is now regarded as receptive.3 Australia's receptivity was tested with the return of large numbers of infected servicemen after the world wars: few malaria infections were transmitted outside the receptive zone.3 Even within the receptive zone, local transmission is rare despite imported cases. Possible reasons include: Australian mosquitoes may not be susceptible to imported malaria parasites. Not all vectors and malaria strains are compatible; the European vector, An. atroparvus, cannot be infected with an African strain of Plasmodium falciparum.10 The susceptibility of Australian mosquitoes to parasites from different geographic regions is largely unknown. Many cases of falciparum malaria do not produce gametocytes to infect vectors, as over half the notified cases are diagnosed (and presumably treated) within three days of onset of symptoms; 11P. falciparum gametocytes mature about 10 days after the appearance of asexual parasites.5 Only 25% of P. falciparum-infected patients from 1989 to 1995 in New South Wales were gametocytaemic at diagnosis (Dr J Walker, Centre for Infectious Diseases and Microbiology, Westmead Hospital, NSW, personal communication). Mosquito-to-human density is low. Anopheles mosquitoes usually have a restricted flight range of 1-2 km. The most prolific larval habitats are permanent or semipermanent natural pools, which are uncommon in urban areas. A low proportion of blood meals are taken from humans. Anopheles mosquitoes feed at night and in Australia are both reluctant to enter houses and restricted by the widespread use of screens (some introduced cases have occurred in soldiers in camps and prospectors who were not so protected3). Feeding on humans is reduced further by the use of repellents and the presence of alternative hosts; An. farauti s.l. in Darwin fed preferentially from dogs rather than humans.12Vector longevity is short. In Darwin only 3%-4.3% of An. farauti s.l. mosquitoes, 0.1%-2.6% of An. bancroftii and 0.3% of An. hilli lived long enough to allow sporozoite development.13The futureThe worsening malaria situation in some neighbouring countries and increasing travel between them and Australia led the incidence of imported malaria to nearly double in Australia between 1981 and 1991.11 Combined with the possibility of expanded vector distribution due to climate change, this has led to calls for reassessment of Australia's receptiveness to malaria.14 Climate change is expected to lead to: More frequent cyclones and floods, which will increase vector density and the risk of malaria. Past epidemics were often associated with above-average rainfall.3Inundation of low-lying areas, due to raised sea levels. Within the Asia-Pacific Region, many such areas are malarious and refugees from them could provide a large reservoir of infection. Emergency relocation of refugees, particularly if aircraft are used, will increase the possibility of introducing exotic vectors into Australia. Drug-resistant malaria parasites will add to the difficulties of treatment. Changes in vector distributionAs An. farauti sensu stricto (s.s.) (or No. 1 of the three species belonging to An. farauti sensu lato)15 is an important vector,16 we investigated its present and future distribution with the CLIMEX climate-matching model17 and the method of Hutchinson to infer meteorological data.18 An annual ecoclimatic index was derived for each location to describe its climatic suitability for the persistence and growth of the mosquito population on a scale of 0-100. Parameter values for climate matching were derived from field studies of the distribution and phenology of An. farauti s.s. and temperature-controlled experiments with the mosquito.16,19,20 The potential distribution of An. farauti s.s. was estimated under a recent climate-change scenario for the year 2030, with increases of 1.5oC in temperature and 10% in summer rainfall in northern Australia21(Figure 3). The present modelled distribution of An. farauti s.s. is largely coastal, which agrees with its known distribution on the Cape York Peninsula and in the Northern Territory. An. farauti s.l. occurs rarely in northern Western Australia (it has been recorded only twice, at Kununurra16), but this was not predicted, probably because it requires exceptionally rainy years or irrigation to survive. Under the climate-change scenario for the year 2030, the potential distribution of An. farauti s.s. extends a further 800 km south in coastal Queensland, to Gladstone (23o50'S). This would encompass the Whitsunday Passage with its tourist population. However, the ecoclimatic indices from Townsville south are low, indicating a limited vector density and hence a low receptivity for malaria. ConclusionsMalaria has long been a threat in Australia, but recently the threat has been sensationalised.14 It is timely to recall Mapleton's advice, given in 1922 in the MJA,22to cease making "tropical Australia appear a hot-bed of dread diseases". In the last 70 years, our understanding of malaria and our ability to control it have increased. Our study indicates that conditions under climate change will become more suitable for the primary vector. To meet this challenge we require vigilance, an understanding of malaria epidemiology and a dispassionate assessment of the risks. [[{"type":"media","view_mode":"media_large","fid":"39843","attributes":{"alt":"","class":"media-image","typeof":"foaf:Image"}}]] Figure 3: The distribution of Anopheles farauti sensu stricto, modelled under the climate at present and as predicted for the year 2030. References Evans W. Antimalarial work in the Australian Mounted Division, Palestine. Its relation to the same problem in Australia. Med J Aust 1919; 2: 526-529. Sutherst RW. Arthropods as disease vectors in a changing environment. In: Lake JV, Bock GR, Ackrill K, editors. Environmental change and human health. Chichester: John Wiley and Sons, 1993: 124-145. Black RH. Malaria in Australia. Sydney: University of Sydney, 1972. World Health Organization. Synopsis of the world malaria situation in 1981. Wkly Epidemiol Rec 1983; 58: 197-199. Bruce-Chwatt LJ. Essential malariology. London: William Heinemann Medical Books Ltd, 1980: 23. Mackerras IM. The Australasian anophelines as vectors of malaria. Med J Aust 1947; 1: 1-8. Bryan JH. Studies on the Anopheles punctulatus complex. 1. Identification by proboscis morphological criteria and by cross-mating experiments. Trans R Soc Trop Med Hyg 1973; 67: 64-69. Mahon RJ, Miethke PM. Anopheles farauti No. 3, a hitherto unrecognized biological species of mosquito within the taxon A. farauti Laveran (Diptera: Culicidae). Trans R Soc Trop Med Hyg 1982; 76: 8-12. Ford E. The malaria problem in Australia and the Australian Pacific Territories. Med J Aust 1950; 23: 749-760. Shute PG. Failure to infect English specimens of Anopheles maculipennis var. atroparvus with certain strains of Plasmodium falciparum of tropical origin. J Trop Med Hyg 1940; 43: 175-178. Sleigh A, Srinivasa M, Cooper A, et al. Report of the Australian malaria register for 1991. Brisbane: Tropical Health Program, 1992: 4; 1. Foley DH, Whelan P, Bryan JH. A study of two sibling species of Anopheles farauti Laveran sensu lato (Diptera: Culicidae) at Darwin, Northern Territory. J Aust Entomol Soc 1991; 30: 269-277. Russell RC. Seasonal abundance, longevity and population age composition of potential malaria vectors in northern and southern Australia. Aust J Zool 1987; 35: 289-306. Murray-Smith S, Weinstein P. A time bomb in north Queensland: a case report of introduced malaria south of the nineteenth parallel. Comm Dis Intell 1993; 17: 211-213. Foley DH, Meek SR, Bryan JH. The Anopheles punctulatus group of mosquitoes in the Solomon Islands and Vanuatu surveyed by allozyme electrophoresis. Med Vet Entomol 1994; 8: 340-350. Lee DJ, Hicks MM, Griffiths M, et al. The Culicidae of the Australasian region, Vol. 5. Canberra: AGPS, 1987: 186-195. Sutherst RW, Maywald GF, Skarratt DB. Predicting insect distributions in a changed climate. In: Harrington R, Stork NE, editors. Insects in a changing environment. London: Academic Press, 1995: 59-91. Hutchinson MF. A new objective method for spatial interpolation of meteorological data from irregular networks applied to the estimation of monthly mean solar radiation, temperature, precipitation and wind run. CSIRO Div Water Res Tech Memo 1989; 5: 95-104. Sweeney AW, Cooper RD, Frances SP. Distribution of the sibling species of Anopheles farauti in the Cape York Peninsula, Northern Queensland, Australia. J Am Mosq Control Assoc 1990; 6: 425-429. Cooper RD, Frances SP, Sweeney AW. Distribution of members of the Anopheles farauti complex in the Northern Territory of Australia. J Am Mosq Control Assoc 1995; 11: 66-71. CSIRO Division of Atmospheric Research. Climate change scenarios for the Australian region. Melbourne: 1992: 1-6. Maplestone PA. Research in tropical Australia [letter]. Med J Aust 1922; 1: 476-477. Author detailsUniversity of Queensland, Brisbane, QLD.

Joan H Bryan · Desmond H Foley · Robert W Sutherst