New in-field treatment solutions to control Fruit Fly (1)

In-field management of fruit flies in fruiting vegetable crops has relied heavily on regular cover sprays with dimethoate and fenthion. However, recent restrictions in their use, and the possibility of further future restrictions, mean that alternative control options are required. The project aimed to assess a combination of perimeter protein baiting and male annihilation, and alternative chemical options, as well as obtaining data on seasonal fruit fly activity in vegetables. Semi-field trials were performed to assess eight insecticides, applied as cover sprays to fruiting capsicum and zucchini plants, for efficacy against Queensland fruit fly, Bactrocera tryoni, and cucumber fly, Zeugodacus cucumis. Clothianidin was very effective against Queensland fruit fly and cucumber fly. Thiacloprid, imidacloprid, cyantraniliprole and alphacypermethrin were also very effective against Queensland fruit fly, but less so against cucumber fly. Bifenthrin, spinetoram and abamectin demonstrated a suppressive effect. Alpha-cypermethrin, bifenthrin and dimethoate were linked to higher incidence of aphid and silverleaf whitefly infestation. A laboratory trial, in which Queensland fruit fly were exposed to dried insecticide residues on capsicum fruit, found that efficacy of thiacloprid was comparable with dimethoate, and spinetoram had a suppressive effect. Chlorantraniliprole and flubendiamide were ineffective. A trial was performed in a commercial chilli crop in Bundaberg to assess a combination of perimeter protein baiting and male annihilation for management of fruit fly. Sampling of fruit from the trial block throughout harvest found that the treatments successfully prevented infestation: no fruit fly larvae were found in any sampled fruit (a total 6966 fruit, 91 kg), with an upper infestation level of 0.04% (95% confidence). For comparison, sampling was also conducted in a second block, where regular cover sprays with dimethoate, trichlorfon and methomyl were applied. Seven flies were found in fruit sampled from the comparison block (3048 fruit, 49 kg), with an upper infestation level of 0.21% (95% confidence). The trial was repeated on a smaller scale in a research planting of capsicums at Bundaberg Research Facility, using a combination of perimeter protein baiting, male annihilation, and fortnightly cover sprays with spinetoram. A total of 12,995 fruit (2488 kg) were sampled. No larvae were recovered during winter, when fruit fly activity was low; however the control measures were not sufficient to prevent infestation outside of this period. The high local fruit fly pressure at the trial site coupled with the smaller size of the area over which control measures were applied were most likely critical factors. Monitoring was performed to obtain more information on the seasonal activity of fruit flies in vegetable crops in the Bundaberg region. Peak trap catch occurred in the spring, with a second peak in the summer. Monitoring also indicated an edge effect, with more flies caught in traps located along a tree-line, or within the crop close to the treeline, compared with those further within the crop. A trial targeting cucumber fly, using traps baited with a cucumber volatile lure, found that the BioTrap (BioTrap Australia Pty Ltd) was a better performing trap type for this species, catching an average of 9.1 cucumber flies per trap per day, compared with 0.7 cucumber flies per trap per day caught by Bugs for Bugs traps (Bugs for Bugs Pty Ltd). The average sex ratio of trapped flies was 74:26 female:male. However, further trials performed in the Fassifern Valley failed to catch cucumber flies

New in-field treatment solutions to control Fruit Fly (1)

In-field management of fruit flies in fruiting vegetable crops has relied heavily on regular cover sprays with dimethoate and fenthion. However, recent restrictions in their use, and the possibility of further future restrictions, mean that alternative control options are required. The project aimed to assess a combination of perimeter protein baiting and male annihilation, and alternative chemical options, as well as obtaining data on seasonal fruit fly activity in vegetables. Semi-field trials were performed to assess eight insecticides, applied as cover sprays to fruiting capsicum and zucchini plants, for efficacy against Queensland fruit fly, Bactrocera tryoni, and cucumber fly, Zeugodacus cucumis. Clothianidin was very effective against Queensland fruit fly and cucumber fly. Thiacloprid, imidacloprid, cyantraniliprole and alphacypermethrin were also very effective against Queensland fruit fly, but less so against cucumber fly. Bifenthrin, spinetoram and abamectin demonstrated a suppressive effect. Alpha-cypermethrin, bifenthrin and dimethoate were linked to higher incidence of aphid and silverleaf whitefly infestation. A laboratory trial, in which Queensland fruit fly were exposed to dried insecticide residues on capsicum fruit, found that efficacy of thiacloprid was comparable with dimethoate, and spinetoram had a suppressive effect. Chlorantraniliprole and flubendiamide were ineffective. A trial was performed in a commercial chilli crop in Bundaberg to assess a combination of perimeter protein baiting and male annihilation for management of fruit fly. Sampling of fruit from the trial block throughout harvest found that the treatments successfully prevented infestation: no fruit fly larvae were found in any sampled fruit (a total 6966 fruit, 91 kg), with an upper infestation level of 0.04% (95% confidence). For comparison, sampling was also conducted in a second block, where regular cover sprays with dimethoate, trichlorfon and methomyl were applied. Seven flies were found in fruit sampled from the comparison block (3048 fruit, 49 kg), with an upper infestation level of 0.21% (95% confidence). The trial was repeated on a smaller scale in a research planting of capsicums at Bundaberg Research Facility, using a combination of perimeter protein baiting, male annihilation, and fortnightly cover sprays with spinetoram. A total of 12,995 fruit (2488 kg) were sampled. No larvae were recovered during winter, when fruit fly activity was low; however the control measures were not sufficient to prevent infestation outside of this period. The high local fruit fly pressure at the trial site coupled with the smaller size of the area over which control measures were applied were most likely critical factors. Monitoring was performed to obtain more information on the seasonal activity of fruit flies in vegetable crops in the Bundaberg region. Peak trap catch occurred in the spring, with a second peak in the summer. Monitoring also indicated an edge effect, with more flies caught in traps located along a tree-line, or within the crop close to the treeline, compared with those further within the crop. A trial targeting cucumber fly, using traps baited with a cucumber volatile lure, found that the BioTrap (BioTrap Australia Pty Ltd) was a better performing trap type for this species, catching an average of 9.1 cucumber flies per trap per day, compared with 0.7 cucumber flies per trap per day caught by Bugs for Bugs traps (Bugs for Bugs Pty Ltd). The average sex ratio of trapped flies was 74:26 female:male. However, further trials performed in the Fassifern Valley failed to catch cucumber flies

The role of spiders as predators of two lepidopteran Brassica pests

Spiders are thought to play a significant role in limiting pest outbreaks in agroecosystems such as vineyards, orchards and cotton. The diversity and impact of spiders in vegetable crops are less well understood, although there is evidence that predators may be important for suppression of lepidopteran pests in Brassica crops, particularly early in the season before parasitoids become established. Sampling was conducted in early season plantings of Brassicas in the Lockyer Valley (South East Queensland, Australia) in order to determine the most commonly occurring spider families. The most numerous were Theridiidae, which were more strongly associated with cauliflower and poorly associated with cabbage. The Lycosidae and Clubionidae/Miturgidae (formerly in the ‘catch-all’ family Clubionidae) also occurred commonly. Lycosidae (and to a lesser extent Salticidae) had above average abundance in Chinese cabbage and below average abundance in broccoli compared with average abundance for these spider families; Clubionidae/Miturgidae had above average abundance in cauliflower. Laboratory studies were then conducted to explore the predatory capacity of these three most commonly occurring spider families. All three were capable of feeding on larvae of the diamondback moth, Plutella xylostella (Linnaeus), and cabbage cluster caterpillar, Crocidolomia pavonana (Fabricius), under laboratory conditions. Theridiidae, which are thought to prey on small pests such as leafhoppers and aphids, were able to successfully attack larvae up to five times their body size. Predation rates varied from an average of 1.7 (SE = 0.47) (1.6 control corrected) larvae consumed over a 24 h period in the case of the Theridiidae, to 3.3 (SE = 0.60) larvae for the Clubionidae/Miturgidae

Protein feeding of Queensland fruit fly Bactrocera tryoni and cucumber fly Zeugodacus cucumis (Diptera: Tephritidae) on non-host vegetation: effect of plant species and bait height

Perimeter-baiting of non-crop vegetation using toxic protein baits was developed overseas as a technique for control of melon fly, Zeugodacus (Zeugodacus) cucurbitae (Coquillett) (formerly Bactrocera (Zeugodacus) cucurbitae), and evidence suggests that this technique may also be effective in Australia for control of local fruit fly species in vegetable crops. Using field cage trials and laboratory reared flies, primary data were generated to support this approach by testing fruit flies' feeding response to protein when applied to eight plant species (forage sorghum, grain sorghum, sweet corn, sugarcane, eggplant, cassava, lilly pilly and orange jessamine) and applied at three heights (1, 1.5 and 2 m). When compared across the plants, Queensland fruit fly, Bactrocera tryoni (Froggatt), most commonly fed on protein bait applied to sugarcane and cassava, whereas more cucumber fly, Zeugodacus (Austrodacus) cucumis (French) (formerly Bactrocera (Austrodacus) cucumis), fed on bait applied to sweet corn and forage sorghum. When protein bait was applied at different heights, B. tryoni responded most to bait placed in the upper part of the plants (2 m), whereas Z. cucumis preferred bait placed lower on the plants (1 and 1.5 m). These results have implications for optimal placement of protein bait for best practice control of fruit flies in vegetable crops and suggest that the two species exhibit different foraging behaviours

Efficiency and safety of varying the frequency of whole blood donation (INTERVAL): a randomised trial of 45 000 donors

Background: Limits on the frequency of whole blood donation exist primarily to safeguard donor health. However, there is substantial variation across blood services in the maximum frequency of donations allowed. We compared standard practice in the UK with shorter inter-donation intervals used in other countries. Methods: In this parallel group, pragmatic, randomised trial, we recruited whole blood donors aged 18 years or older from 25 centres across England, UK. By use of a computer-based algorithm, men were randomly assigned (1:1:1) to 12-week (standard) versus 10-week versus 8-week inter-donation intervals, and women were randomly assigned (1:1:1) to 16-week (standard) versus 14-week versus 12-week intervals. Participants were not masked to their allocated intervention group. The primary outcome was the number of donations over 2 years. Secondary outcomes related to safety were quality of life, symptoms potentially related to donation, physical activity, cognitive function, haemoglobin and ferritin concentrations, and deferrals because of low haemoglobin. This trial is registered with ISRCTN, number ISRCTN24760606, and is ongoing but no longer recruiting participants. Findings: 45 263 whole blood donors (22 466 men, 22 797 women) were recruited between June 11, 2012, and June 15, 2014. Data were analysed for 45 042 (99·5%) participants. Men were randomly assigned to the 12-week (n=7452) versus 10-week (n=7449) versus 8-week (n=7456) groups; and women to the 16-week (n=7550) versus 14-week (n=7567) versus 12-week (n=7568) groups. In men, compared with the 12-week group, the mean amount of blood collected per donor over 2 years increased by 1·69 units (95% CI 1·59–1·80; approximately 795 mL) in the 8-week group and by 0·79 units (0·69–0·88; approximately 370 mL) in the 10-week group (p<0·0001 for both). In women, compared with the 16-week group, it increased by 0·84 units (95% CI 0·76–0·91; approximately 395 mL) in the 12-week group and by 0·46 units (0·39–0·53; approximately 215 mL) in the 14-week group (p<0·0001 for both). No significant differences were observed in quality of life, physical activity, or cognitive function across randomised groups. However, more frequent donation resulted in more donation-related symptoms (eg, tiredness, breathlessness, feeling faint, dizziness, and restless legs, especially among men [for all listed symptoms]), lower mean haemoglobin and ferritin concentrations, and more deferrals for low haemoglobin (p<0·0001 for each) than those observed in the standard frequency groups. Interpretation: Over 2 years, more frequent donation than is standard practice in the UK collected substantially more blood without having a major effect on donors' quality of life, physical activity, or cognitive function, but resulted in more donation-related symptoms, deferrals, and iron deficiency. Funding: NHS Blood and Transplant, National Institute for Health Research, UK Medical Research Council, and British Heart Foundation

Longer-term efficiency and safety of increasing the frequency of whole blood donation (INTERVAL): extension study of a randomised trial of 20 757 blood donors

Background: The INTERVAL trial showed that, over a 2-year period, inter-donation intervals for whole blood donation can be safely reduced to meet blood shortages. We extended the INTERVAL trial for a further 2 years to evaluate the longer-term risks and benefits of varying inter-donation intervals, and to compare routine versus more intensive reminders to help donors keep appointments. Methods: The INTERVAL trial was a parallel group, pragmatic, randomised trial that recruited blood donors aged 18 years or older from 25 static donor centres of NHS Blood and Transplant across England, UK. Here we report on the prespecified analyses after 4 years of follow-up. Participants were whole blood donors who agreed to continue trial participation on their originally allocated inter-donation intervals (men: 12, 10, and 8 weeks; women: 16, 14, and 12 weeks). They were further block-randomised (1:1) to routine versus more intensive reminders using computer-generated random sequences. The prespecified primary outcome was units of blood collected per year analysed in the intention-to-treat population. Secondary outcomes related to safety were quality of life, self-reported symptoms potentially related to donation, haemoglobin and ferritin concentrations, and deferrals because of low haemoglobin and other factors. This trial is registered with ISRCTN, number ISRCTN24760606, and has completed. Findings: Between Oct 19, 2014, and May 3, 2016, 20 757 of the 38 035 invited blood donors (10 843 [58%] men, 9914 [51%] women) participated in the extension study. 10 378 (50%) were randomly assigned to routine reminders and 10 379 (50%) were randomly assigned to more intensive reminders. Median follow-up was 1·1 years (IQR 0·7–1·3). Compared with routine reminders, more intensive reminders increased blood collection by a mean of 0·11 units per year (95% CI 0·04–0·17; p=0·0003) in men and 0·06 units per year (0·01–0·11; p=0·0094) in women. During the extension study, each week shorter inter-donation interval increased blood collection by a mean of 0·23 units per year (0·21–0·25) in men and 0·14 units per year (0·12–0·15) in women (both p<0·0001). More frequent donation resulted in more deferrals for low haemoglobin (odds ratio per week shorter inter-donation interval 1·19 [95% CI 1·15–1·22] in men and 1·10 [1·06–1·14] in women), and lower mean haemoglobin (difference per week shorter inter-donation interval −0·84 g/L [95% CI −0·99 to −0·70] in men and −0·45 g/L [–0·59 to −0·31] in women) and ferritin concentrations (percentage difference per week shorter inter-donation interval −6·5% [95% CI −7·6 to −5·5] in men and −5·3% [–6·5 to −4·2] in women; all p<0·0001). No differences were observed in quality of life, serious adverse events, or self-reported symptoms (p>0.0001 for tests of linear trend by inter-donation intervals) other than a higher reported frequency of doctor-diagnosed low iron concentrations and prescription of iron supplements in men (p<0·0001). Interpretation: During a period of up to 4 years, shorter inter-donation intervals and more intensive reminders resulted in more blood being collected without a detectable effect on donors' mental and physical wellbeing. However, donors had decreased haemoglobin concentrations and more self-reported symptoms compared with the initial 2 years of the trial. Our findings suggest that blood collection services could safely use shorter donation intervals and more intensive reminders to meet shortages, for donors who maintain adequate haemoglobin concentrations and iron stores. Funding: NHS Blood and Transplant, UK National Institute for Health Research, UK Medical Research Council, and British Heart Foundation

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

ANIMAL MODELS FOR THE STUDY OF LEISHMANIASIS IMMUNOLOGY

Leishmaniasis remains a major public health problem worldwide and is classified as Category I by the TDR/WHO, mainly due to the absence of control. Many experimental models like rodents, dogs and monkeys have been developed, each with specific features, in order to characterize the immune response to Leishmania species, but none reproduces the pathology observed in human disease. Conflicting data may arise in part because different parasite strains or species are being examined, different tissue targets (mice footpad, ear, or base of tail) are being infected, and different numbers (“low” 1×102 and “high” 1×106) of metacyclic promastigotes have been inoculated. Recently, new approaches have been proposed to provide more meaningful data regarding the host response and pathogenesis that parallels human disease. The use of sand fly saliva and low numbers of parasites in experimental infections has led to mimic natural transmission and find new molecules and immune mechanisms which should be considered when designing vaccines and control strategies. Moreover, the use of wild rodents as experimental models has been proposed as a good alternative for studying the host-pathogen relationships and for testing candidate vaccines. To date, using natural reservoirs to study Leishmania infection has been challenging because immunologic reagents for use in wild rodents are lacking. This review discusses the principal immunological findings against Leishmania infection in different animal models highlighting the importance of using experimental conditions similar to natural transmission and reservoir species as experimental models to study the immunopathology of the disease