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Primaquine is the only drug available to prevent relapse in vivax malaria. The main adverse effect of primaquine is erythrocyte age and dose-dependent acute haemolytic anaemia in individuals with glucose-6-phosphate dehydrogenase deficiency (G6PDd). As testing for G6PDd is often unavailable, this limits the use of primaquine for radical cure. A compartmental model of the dynamics of red blood cell production and destruction was designed to characterise primaquine-induced haemolysis using a holistic Bayesian analysis of all published data and was used to predict a safer alternative to the currently recommended once weekly 0.75 mg/kg regimen for G6PDd. The model suggests that a step-wise increase in daily administered primaquine dose would be relatively safe in G6PDd. If this is confirmed, then were this regimen to be recommended for radical cure patients would not require testing for G6PDd in areas where G6PDd Viangchan or milder variants are prevalent. DOI: http://dx.doi.org/10.7554/eLife.23061.001, eLife digest Malaria is the most important parasitic disease that affects humans. Over half of the malaria cases in Asia and South America are caused by a species of malaria parasite called Plasmodium vivax (known as vivax malaria). This form of malaria results in repeated illness because dormant parasites in the liver wake at intervals to infect the blood. The only available drug that can stop these relapses is a drug called primaquine, which was developed seventy years ago. Unfortunately, primaquine causes dangerous side effects in certain individuals who are deficient in an enzyme called G6PD, which helps defend red blood cells against stresses. Primaquine damages these cells so that they burst, leading to anaemia. This is a major problem because G6PD deficiency is common in regions where malaria is present: in some areas up to 30% of the population may be G6PD deficient. Since G6PD testing is not widely available, doctors often avoid prescribing primaquine to treat malaria, which results in more cases of disease relapse. Failing to prevent vivax relapses causes extensive illness and hinders efforts to eliminate malaria. Is there a way to give this drug to patients that would be safer for people with G6PD deficiency? Primaquine destroys older rather than younger red blood cells. Watson et al. used mathematical modelling to see whether it is possible to develop a primaquine treatment strategy that would allow a gradual destruction of older red blood cells in individuals with G6PD deficiency, which would be safer. The mathematical model incorporates data from previous studies in malaria patients and healthy volunteers with G6PD deficiency and combines this with knowledge of how red blood cells are produced and destroyed. Watson et al. predicted that giving primaquine over 20 days in a steadily increasing dose was safer than current recommendations. Mathematical models are simplifications of real world processes. The only way to test these findings properly will be to run a clinical trial that gives healthy volunteers who are G6PD deficient a course of primaquine treatment with a steadily increasing dose. DOI: http://dx.doi.org/10.7554/eLife.23061.002

Information on forest use and dependence on tree hollows was collated for vertebrates in the Top End of the Northern Territory. The proportion of the total fauna that used hollows was 40% for mamma...

Bird communities in montane wet forest at three sites (altitudes 700,750 and 880 m) on the Central Plateau of Tasmania were surveyed over a 12-month period between December 1991 and November 1992. Monthly transect counts were carried out at each site. Snowf:,lls are common at all three sites during winter and snow can remain at the highest site for several weeks. Bird communities at the study sites showed significant differences in densities and seasonal patterns even though species composition was similar. These differences were influenced by the variation in habitats and the environments at the sites. Butlers Road, the lowest site with the mildest winters and greatest proportion of drier habitat, had the highest bird densities, while D'Arcys Bluff, at the highest altitude, had the lowest. The degree of seasonal changes of birds was similar to mainland montane wet forests, with over half the species moving either locally or to the mainland, However, there was variation in seasonal occurrences between the study sites, with proportionally more species moving from the highest site during the winter, Within the study sites, the wet forest habitats with a diverse shrub and/or fern understorey supported higher bird populations than did mixed forest and damp forest. Species richness is lower at these sites compared with equivalent montane forests on mainland southeastern Australia.

Activity patterns of geometrid moths were compared in two areas, one in wet eucalypt forest at high altitude and the other in mainly dry forest at low altitude in Tasmania. One hundred and twenty-six species were able to be grouped into six distinct groups (i.e. spring, spring and summer, summer, autumn, autumn and winter, all year) in terms of their patterns of seasonal occurrence. Three of the 16 species common to the two sites differed in their seasonality of occurrence, with their length of occurrence being extended at Old Chum Dam compared with Central Plateau. Moth numbers strongly reflected monthly changes in minimum temperature, with moth activity being greater at the high altitude site than at the low altitude site for an equivalent temperature. However, a given change in minimum temperature led to an equivalent change in the magnitude of moth numbers at both sites. These seasonal patterns of occurrence must be considered in the planning of biodiversity surveys.

Millipedes were sampled by hand-collecting from plots and by pitfall trapping at three forest sites in central Tasmania. Seven days of pitfall trapping each month over one year was less efficient than four weeks of hand-collecting in autumn, yielding fewer species and fewer specimens per working day in the field. Hand-collecting is likely to provide more accurate data on species diversity and relative abundance for a range of litter invertebrates.

A survey of small terrestrial mammals and bats was undertaken in two areas of southwestern Tasmania: around Melaleuca, in sedgeland, scrub and woodland communities, and at Claytons in mixed forest. The density of bats was extremely low in comparison with populations in eastern Tasmania. The densities of Rattus lutreolusand Antechinus minimuswere greatest in sedgeland/scrub with a dense undergrowth. Pseudomys higginsi was only captured in mixed forest but is also present around Deny King's garden. Dasyurus viverrinus was most abundant in young sedgeland. Cercartetus nanus was present at both Clay tons and Melaleuca. No introduced rodents were trapped, but an outbreak of Rattus rattus had occurred previous to our study. No Mastacomys fuscus were trapped but they have been recorded in a previous study. Fire has an important influence on the composition and structure of the vegetation which, in turn, influences the composition and density of the mammal community.

A list of colcopteran, large collembolan, centipede, miilipede and molluscan specics associated with rotting logs was compiled for an old-growth Eucalyptus obliqua wet sclerophyll forest and adjacent 19- year-old regeneration in southern Tasmania. A total of 67 species were found, 40 occurring in both areas, 53 in old-growth forest and 54 in the regenerated area. Of the species found in only one of the areas, nearly all occured in one or two samples only, so no conclusion about their absence from the other area can be made. Two rarely collected species of beetles were recorded only in the old growth forest. Conservation of log-dwelling invertebrates in production forests is discussed.

Background The clinical presentation of malaria, considered as the result of a complex interaction between parasite and human genetics, is described to be different between rural and urban areas. The analysis of the Plasmodium falciparum genetic diversity in children with uncomplicated malaria, living in these two different areas, may help to understand the effect of urbanization on the distribution of P. falciparum genotypes. Methods Isolates collected from 75 and 89 children with uncomplicated malaria infection living in a rural and an urban area of Burkina Faso, respectively, were analysed by a nested PCR amplification of msp1 and msp2 genes to compare P. falciparum diversity. Results The K1 allelic family was widespread in children living in the two sites, compared to other msp1 allelic families (frequency >90%). The MAD 20 allelic family of msp1 was more prevalent (p = 0.0001) in the urban (85.3%) than the rural area (63.2%). In the urban area, the 3D7 alleles of msp2 were more prevalent compared to FC27 alleles, with a high frequency for the 3D7 300bp allele (>30%). The multiplicity of infection was in the range of one to six in the urban area and of one to seven in the rural area. There was no difference in the frequency of multiple infections (p = 0.6): 96.0% (95% C.I: 91.6–100) in urban versus 93.1% (95%C.I: 87.6–98.6) in rural areas. The complexity of infection increased with age [p = 0.04 (rural area), p = 0.06 (urban area)]. Conclusion Urban-rural area differences were observed in some allelic families (MAD20, FC27, 3D7), suggesting a probable impact of urbanization on genetic variability of P. falciparum. This should be taken into account in the implementation of malaria control measures.

Distribution records and details of habitat are provided for Helicarion rubicundus, a land snail. This was known from one location. It was found to occur through much of the wet forest on Forestier Peninsula but to be rare within suitable habitat on Tasman Peninsula.

The effect of glyphosate on seedhead development of bent grass (Agrostis castellana) was evaluated in an experiment at 2 sites in south-western Victoria.Application of glyphosate at 0.1350.225 kg a.i./ha on 7 November and 7 December 1993 prevented the formation of seedheads and stimulated the plant into renewed vegetative growth in response to following summer rain. The treatment with 0.135 kg a.i./ha of glyphosate, applied on 7 November, increased digestible dry matter of the regrowth by 20% and protein content by 70% compared with the unsprayed control which was dominated by seedheads. These results reflect the amount of new growth in treated plots and thus should not be confused with either the 'spraytopping' technique which aims to sterilise seeds after seedhead emergence or 'hay freezing' which and aims to preserve the feed value of existing vegetation by 'chemically curing' standing hay. We conclude that application of glyphosate at 0.135 kg a.i./ha in early November has the potential to reduce the dominance of bent grass, creating an opportunity for follow up fertiliser and management techniques to maintain productive pastures.

The distributions of 34 species of terrestrial mammals native to Tasmania are presented as presence/ absence records on 10 x 10 km grid maps. All native species and the possibly introduced Petaurus breviceps are included except Thylacinus cynocephalus, which is probably extinct. The distribution maps were prepared from approximately 10 000 recent (1967-89) mammal records held on computer, selected literature records and other sources. Twenty-six species are widely distributed across the State. Five species have more limited distributions confined to the east or west of the State, depending upon the occurrence of their habitats. The three remaining species are bats that are little-recorded and their distributions are unclear. Notes on the ease of recording species and their habitats are provided to supplement and assist the interpretation of their distributions. Further records of all species are needed, especially from islands.

Photographs of the hair structure of the five species of Tasmanian mammals (Sarcophilus harrisii, Thylacinus cynocephalus, Bettongia gaimardi, Cercartetus lepidus and Pseudomys higginsi) which have not been described by Brunner & Coman (1974) are presented. A key to the hair of forty Tasmanian mammals is provided to allow the identification of unknown samples. The key can be used in mammal surveys and in carnivore dietary studies.

All four of Tasmania's large mammalian carnivores (Sarcophilus harrisii, Dasyurus maculatus, D. viverrinus, Felis catus) occur in the Upper Henty River region~ in western Tasmania. A short-term study was undertaken to compare the diet of these species when in sympatry. No data were obtained for D. maculatus. The other species overlapped in their use of small mammals. However each species had a major component of the diet (S. harrisii, large mammals; D. viverrinus, invertebrates and plant material; F. catus,birds)which was not utilized by the other species and hence substantial competition between them is unlikely. The diet reported others for D. maculatus is similar to that found for F. catus. These two species had similar habit preferences and hence it is possible that competition could occur between the native D. maculatus and the introduced F. catus.

A review of the natural history of bats in Tasmania is presented along with data collected in recent surveys. Recent taxonomic changes affecting the Tasmanian bat species are discussed and a key is provided to allow the identification of Tasmanian bats. The appearance of each species is described and body measurements given. Tasmanian populations do not show a uniform trend of increased size compared with southeast Australian populations. Distribution records are presented along with data on habitat preferences and abundance. The diet, activity patterns, roosting requirements, reproductive cycles and conservation status of the species are also discussed.

A mammal survey was conducted in the Upper Henty River Region in western Tasmania. The area had been subject to much disturbance from mining, forestry and frequent fires and was covered by a maze of roads and tracks. Nineteen native species (including bats) were recorded. Four of the species listed in 1983 as occurring in the Lower Gordon Region, 80 km south ofthe present study area, were not recorded during our survey. It is considered that three of these species would probably have been found in the area with further searching. The fourth species, Mastacomysfuscus, is thought not to be present due to increased fire frequency in the sedgeland areas compared with the Lower Gordon Region. Potorous tridactylus is recorded for the first time from rainforest. Microhabitat selection by Rattus lutreolus and Pseudomys higginsi differed from that previously reported. Disturbance from road construction led to the creation ofa new food source for Thylogale billardierii. The abundance of tracks in the area increased ease of movement for carnivorous mammals. Only one introduced species Felis catus, which is also known to occur in the Lower Gordon, was recorded. Disturbance had thus not led to an invasion of exotics.

An epidemiological study of atrophic rhinitis was carried out in four pig herds. Observations were made of (i) infection with Bordetella bronchiseptica and Pasteurella multocida, (ii) the presence of brachygnathia superior (BS score), (iii) the extent (grade) of turbinate atrophy and pneumonia at slaughter and (iv) growth rates from two to 16 weeks of age and average daily weight gains to slaughter. In two of the herds with no history of atrophic rhinitis, B bronchiseptica and non-toxigenic strains of P multocida were isolated; only one of 47 pigs (2 per cent) had a BS score greater than +10 mm and the most severe turbinate atrophy observed in 21 pigs at slaughter was grade 3. In contrast, from two herds with atrophic rhinitis, toxigenic strains of P multocida were isolated as well as B bronchiseptica and non-toxigenic P multocida. BS scores of greater than +10 mm were present in six of 47 pigs (13 per cent) of which five were infected with toxigenic P multocida and had severe turbinate atrophy of grade 4 or 5. There was no significant reduction in growth rates in the affected compared with the unaffected herds nor in the affected compared with the unaffected pigs in the same herd. Neither was there a correlation between progressive disease and the extent of pneumonia found at slaughter. It was concluded that in field cases of the disease, high BS scores plus severe turbinate atrophy were associated with infection by toxigenic type-D strains of P multocida.

Growth of pouch young of Bettongia gaimardi was compared in laboratory and field populations. Up to a pes length of 8 cm, weights of field and laboratory young were similar. For larger young, weights for field animals were significantly less than for those raised in captivity. The two groups did not differ in rate of growth of pes or in skeletal proportions. Previous studies of macropodids have found that growth rates are reduced only during periods of severe environmental stress. In contrast, in field populations of B. gaimardi lower growth rates of pouch young appear to be the norm. Differences in the seasonality and availability of food supplies between B. gaimardi and other species so far studied may be responsible for this difference.

Observations were made on the flight patterns and foraging behaviour of Tasmanian bat species, by the use of light tags and the release of individuals at dusk while it was still light enough to see clearly. Four distinct foraging patterns were observed, each being characteristic of a pair of species. These pairs were: Nyctophrlusgeoffroyi and N. timoriensis (slowest flight, undulating, closest to vegetation); Eptesicus vulturnus and E. regulus (highly manoeuvrable, faster than Nyctophilus, further from vegetation); E. sagittula and Chalinolobus morio (fast, direct flight, less manoeuvrable than smaller Eptesicus and fly higher); and Pipistrellus tasmaniensis and C. gouldii (faster, most direct flight, limited manoeuvrability, prefer open areas). There is a broad agreement between the flight patterns observed and the relative shape of the wing of each species.

Nightly activity patterns of seven species of bats (Eptesicus vulturnus, E. regulus, E. sagittula, Nyctophilus geoffroyi, N. timoriensis, Chalinolobus morio and FalsistreNus tasmaniensis) and their volant insect prey were studied during late spring and summer at four sites in Tasmania. Activity of bats was assessed from trapping results. Bats exhibited a biomodal pattern of foraging activity being most active in the first hours after dark, declining to low levels in the middle part of the night and rising again to a secondary peak in the three hours before dawn. These patterns of activity in bats closely reflected the patterns of insect activity. The insectivorous bats thus appear to have adjusted their nightly activities to match those of their prey, thereby maximising foraging success and energy gains.

Data were collected on the occurrence of eastern grey kangaroos and wallaroos in groups on two properties (Lana and Newholme) in north-eastern New South Wales. The density of both species was higher on Lana than on Newholme. The frequency of occurrence of groups of different size was significantly different from that expected if the occurrence was random for both species. For the grey kangaroo on Lana, mean group size was smaller during early morning than during the rest of the day. Mean group size was significantly greater on Lana than on Newholme for both species, and smaller for wallaroos than for grey kangaroos on both properties. For both species, mean group size was significantly correlated with the density of kangaroos in each habitat.

The diet of the eastern grey kangaroo and wallaroo was compared at 2 sites, Lana and Newsholme, in the New England tablelands of New South Wales. At Lana, the pastures had been fertilized for 20 yr and were dominated by low-fibre grasses such as Bothriochloa, Eragrostis, Sporobolus, Microlaena, Danthonia and Vulpia; some paddocks had been sown with introduced grasses, Phalaris, Festuca and lucerne. Coarse tussock grasses such as Poa spp., Stipa and Danthonia pallida predominated at Newsholme. The major difference in the diet of the 2 spp. was in winter when individuals on the unimproved area at Newsholme ate a higher proportion of tussock grasses and less low-fibre grass. Both spp. consistently selected for low-fibre grass leaf; they did not differ in their use of plant parts. The diets contained many plant spp. in common, although there were major differences in the use of several spp. The plant spp. favoured only by the wallaroo were of a higher quality than those favoured only by the grew kangaroo.

Roosting requirements and movements between foraging areas and roost sites were studied in Eptesicus regulus, E. sagittula, Chalinolobus morio and Nyctophilus geoffroyi in an area of artificially regenerated eucalypt (Eucalyptus) forest surrounded by mature eucalypt forest. Movements between traps and roost sites were normally about 1 km, with the maximum distance recorded being 4.8 km for a female N. geoffroyi. Different species of eucalypts were used as roost sites in proportion to their occurrence in the forest. However, large trees over 80 cm d.b.h. were favoured. There was no tendency to avoid roost sites close to the ground. Spaces used as roost sites had one dimension little greater than the bat itself. Five types of roost sites were distinguished: in fissures, inside burnt-out boles, in hollows, under bark and on the ground. Individuals changed roost sites frequently but roosts used by any one individual were in the same general vicinity. The factors associated with production of roost sites in trees were: large size, overmaturity, death, rot and fire. No bats were found to roost in regenerated forest. Patches of mature forest will need to be retained to ensure a shortage of roosts does not occur as more areas of mature forest are converted to production forest.