Insect pathogens as biological control agents: Back to the future.

The development and use of entomopathogens as classical, conservation and augmentative biological control agents have included a number of successes and some setbacks in the past 1years. In this forum paper we present current information on development, use and future directions of insect-specific viruses, bacteria, fungi and nematodes as components of integrated pest management strategies for control of arthropod pests of crops, forests, urban habitats, and insects of medical and veterinary importance. Insect pathogenic viruses are a fruitful source of microbial control agents (MCAs), particularly for the control of lepidopteran pests. Most research is focused on the baculoviruses, important pathogens of some globally important pests for which control has become difficult due to either pesticide resistance or pressure to reduce pesticide residues. Baculoviruses are accepted as safe, readily mass produced, highly pathogenic and easily formulated and applied control agents. New baculovirus products are appearing in many countries and gaining an increased market share. However, the absence of a practical in vitro mass production system, generally higher production costs, limited post application persistence, slow rate of kill and high host specificity currently contribute to restricted use in pest control. Overcoming these limitations are key research areas for which progress could open up use of insect viruses to much larger markets. A small number of entomopathogenic bacteria have been commercially developed for control of insect pests. These include several Bacillus thuringiensis sub-species, Lysinibacillus (Bacillus) sphaericus, Paenibacillus spp. and Serratia entomophila. B. thuringiensis sub-species kurstaki is the most widely used for control of pest insects of crops and forests, and B. thuringiensis sub-species israelensis and L. sphaericus are the primary pathogens used for control of medically important pests including dipteran vectors. These pathogens combine the advantages of chemical pesticides and MCAs: they are fast acting, easy to produce at a relatively low cost, easy to formulate, have a long shelf life and allow delivery using conventional application equipment and systemics (i.e. in transgenic plants). Unlike broad spectrum chemical pesticides, B. thuringiensis toxins are selective and negative environmental impact is very limited. Of the several commercially produced MCAs, B. thuringiensis (Bt) has more than 50% of market share. Extensive research, particularly on the molecular mode of action of Bt toxins, has been conducted over the past two decades. The Bt genes used in insect-resistant transgenic crops belong to the Cry and vegetative insecticidal protein families of toxins. Bt has been highly efficacious in pest management of corn and cotton, drastically reducing the amount of broad spectrum chemical insecticides used while being safe for consumers and non-target organisms. Despite successes, the adoption of Bt crops has not been without controversy. Although there is a lack of scientific evidence regarding their detrimental effects, this controversy has created the widespread perception in some quarters that Bt crops are dangerous for the environment. In addition to discovery of more efficacious isolates and toxins, an increase in the use of Bt products and transgenes will rely on innovations in formulation, better delivery systems and ultimately, wider public acceptance of transgenic plants expressing insect-specific Bt toxins. Fungi are ubiquitous natural entomopathogens that often cause epizootics in host insects and possess many desirable traits that favor their development as MCAs. Presently, commercialized microbial pesticides based on entomopathogenic fungi largely occupy niche markets. A variety of molecular tools and technologies have recently allowed reclassification of numerous species based on phylogeny, as well as matching anamorphs (asexual forms) and teleomorphs (sexual forms) of several entomopathogenic taxa in the Phylum Ascomycota. Although these fungi have been traditionally regarded exclusively as pathogens of arthropods, recent studies have demonstrated that they occupy a great diversity of ecological niches. Entomopathogenic fungi are now known to be plant endophytes, plant disease antagonists, rhizosphere colonizers, and plant growth promoters. These newly understood attributes provide possibilities to use fungi in multiple roles. In addition to arthropod pest control, some fungal species could simultaneously suppress plant pathogens and plant parasitic nematodes as well as promote plant growth. A greater understanding of fungal ecology is needed to define their roles in nature and evaluate their limitations in biological control. More efficient mass production, formulation and delivery systems must be devised to supply an ever increasing market. More testing under field conditions is required to identify effects of biotic and abiotic factors on efficacy and persistence. Lastly, greater attention must be paid to their use within integrated pest management programs; in particular, strategies that incorporate fungi in combination with arthropod predators and parasitoids need to be defined to ensure compatibility and maximize efficacy. Entomopathogenic nematodes (EPNs) in the genera Steinernema and Heterorhabditis are potent MCAs. Substantial progress in research and application of EPNs has been made in the past decade. The number of target pests shown to be susceptible to EPNs has continued to increase. Advancements in this regard primarily have been made in soil habitats where EPNs are shielded from environmental extremes, but progress has also been made in use of nematodes in above-ground habitats owing to the development of improved protective formulations. Progress has also resulted from advancements in nematode production technology using both in vivo and in vitro systems; novel application methods such as distribution of infected host cadavers; and nematode strain improvement via enhancement and stabilization of beneficial traits. Innovative research has also yielded insights into the fundamentals of EPN biology including major advances in genomics, nematode-bacterial symbiont interactions, ecological relationships, and foraging behavior. Additional research is needed to leverage these basic findings toward direct improvements in microbial control.

Efficacy of the biofumigant fungus Muscodor albus (Ascomycota: Xylariales) for control of codling moth (Lepidoptera: Tortricidae) in simulated storage conditions.

Codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), a serious pest of pome fruit, is a threat to exportation of apples (Malus spp.) because of the possibility of shipping infested fruit. The need for alternatives to fumigants such as methyl bromide for quarantine security of exported fruit has encouraged the development of effective fumigants with reduced side effects. The endophytic fungus Muscodor albus Worapong, Strobel and Hess (Ascomycota: Xylariales) produces volatile compounds that are biocidal for several pest organisms, including plant pathogens and insect pests. The objectives of our research were to determine the effects of M. albus volatile organic compounds (VOCs) on codling moth adults, neonate larvae, larvae in infested apples, and diapausing cocooned larvae in simulated storage conditions. Fumigation of adult codling moth with VOCs produced by M. albus for 3 d and incubating in fresh air for 24 h at 25 degrees C resulted in 81% corrected mortality. Four- and 5-d exposures resulted in higher mortality (84 and 100%, respectively), but control mortality was also high due to the short life span of the moths. Exposure of neonate larvae to VOCs for 3 d on apples and incubating for 7 d resulted in 86% corrected mortality. Treated larvae were predominantly first instars, whereas 85% of control larvae developed to second and third instars. Exposure of apples that had been infested for 5 d, fumigated with M. albus VOCs for 3 d, and incubated as described above resulted in 71% corrected larval mortality. Exposure of diapausing cocooned codling moth larvae to VOCs for 7 or 14 d resulted in 31 and 100% mortality, respectively, with negligible control mortality. Our data on treatment of several stages of codling moth with M. albus VOCs indicate that the fungus could provide an alternative to broad spectrum chemical fumigants for codling moth control in storage and contribute to the systems approach to achieve quarantine security of exported apples.

Evaluation of the pear ester kairomone as a formulation additive for the granulovirus of codling moth (Lepidoptera: Tortricidae) in pome fruit.

(E,Z) -2,4-decadienoate (pear ester) is a larval kairomone for the codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae). Orchard studies were conducted in 2005 and 2006 in apple, Malus domestica Borkhausen, and pear, Pyrus communis L., to evaluate a 5% active ingredient (AI), microencapsulated formulation of pear ester (PE-MEC) as an insecticidal additive for the codling moth granulovirus (CpGV). Although CpGV applied at 5-15-d intervals at commercial rates (2.2 X 10(12)-10(13) granules per ha) killed the majority (82-94%) of larvae found inside infested fruit, it did not eliminate significant damage, i.e., 30-92% fruit injury at harvest versus 51-82% in controls. PE-MEC treatments had significant but inconsistent results in our tests. In apple (mixed cultivars), PE-MEC (3.7-4.7 g [AI] /ha) plus CpGV reduced the percentage of fruit injured during the second but not the first larval generation, compared with CpGV alone, but there no was no additional population reduction (live larvae collected from infested fruit and tree bands). In 'Bartlett' pear, PE-MEC (3.7 g [AI] /ha) plus CpGV significantly increased larval mortality and reduced deep fruit entries at harvest over CpGV alone in 2006, but similar improvements were not observed in 2005 when a lower rate (1.5 g [AI] /ha) was tested. Surprisingly, compared with untreated controls, the PE-MEC formulation alone also reduced fruit injury (mid-season in Bartlett) and larval survivorship inside infested fruit at harvest (2006 apple tests and both years in Bartlett). Although pear ester seems amenable as a kairomonal adjuvant for use with insecticides, our inconsistent data with CpGV in apple and pear suggest practical improvements in formulation and application strategies (e.g., to optimize and maintain attractive release rates) are needed.

Control of the Oriental Fruit Moth, Grapholita molesta, Using Entomopathogenic Nematodes in Laboratory and Fruit Bin Assays.

The oriental fruit moth (OFM), Grapholita molesta (Busck), which is among the most important insect pests of peaches and nectarines, has developed resistance to a wide range of insecticides. We investigated the ability of the entomopathogenic nematodes (EPN) Steinernema carpocapsae (Weiser), S. feltiae (Filipjev), S. riobrave (Cabanillas et al.), and Heterorhabditis marelatus (Liu and Berry) to control OFM under laboratory and fruit bin conditions. At a dosage of 10 infective juveniles (IJ)/cm(2) in the laboratory, S. carpocapsae caused 63%, S. feltiae 87.8%, S. riobrave 75.6%, and H. marelatus 67.1% OFM mortality. All four nematode species caused significant OFM larval mortality in comparison to the nontreated controls. Steinernema feltiae was used for the bin assays due to the higher OFM mortality it caused than the other tested EPN species and to its ability to find OFM under cryptic environments. Diapausing cocooned OFM larvae in miniature fruit bins were susceptible to IJ of S. feltiae in infested corner supports and cardboard strips. Treatment of bins with suspensions of 10 or 25 S. feltiae IJ/ml water with wetting agent (Silwet L77) resulted in 33.3 to 59% and 77.7 to 81.6% OFM mortality in corner supports and cardboard strips, respectively. This paper presents new information on the use of EPN, specifically S. feltiae, as nonchemical means of OFM control.

Optimizing use of codling moth granulovirus: effects of application rate and spraying frequency on control of codling moth larvae in Pacific Northwest apple orchards.

New formulations of the codling moth, Cydia pomonella (L.), granulovirus (CpGV) [family Baculoviridae, genus Granulovirus] are commercially available in North America. In field tests on apple (Malus sp. 'Delicious'), we compared different application strategies for CpGV (Cyd-X, Certis USA, Clovis, CA) used in full-season programs against high pest populations. In replicated single tree plots, three rates (0.073, 0.219, and 0.438 liter ha(-1)) and application intervals (7, 10, and 14 d) killed 81-99% of larvae in fruit and reduced the number of mature larvae recovered in tree bands by 54-98%. Although the proportion of deep entries declined by 77-98%, the amount of fruit injury was not reduced compared with controls. There was a statistical trend between increasing dosage and spray frequency intervals and virus effectiveness, but no interaction between these factors. In a commercial orchard, we assessed a standard (0.219 liter ha(-1)) and two reduced rates of the virus (0.146 and 0.073 liter ha(-1)) applied in a weekly spray program in replicated 0.2-ha blocks. In the first generation, fruit injury was reduced in virus-treated compared with three untreated blocks although the decrease was only significant at the standard rate. Mortality rates of larvae (in fruit) were > or =90%, dose dependent, and comparable with rates observed from individual trees sprayed with equivalent treatments in the previous study. Rates of larval mortality declined at all dosages (81-85%) in the first part of the second generation. Most damage and proportionally less mortality occurred in the upper canopy. High pest pressures and untreated blocks contributed to significant damage and the study was terminated early. These data suggest virus programs can be tailored according to the localized pest pressure, but it may not prevent economic damage in high-pressure situations.

Can higher doses of an H2-receptor antagonist accelerate duodenal ulcer healing?

Drugs that inhibit gastric acid secretion heal duodenal ulcers at a rate that correlates with the ability of individual treatment regimens to decrease 24-h intragastric acidity. As current therapeutic regimens of ranitidine decrease 24-h intragastric acidity submaximally, higher dosages may expedite duodenal ulcer healing. To test this hypothesis a randomized, double-blind clinical trial was conducted in 245 patients with duodenal ulcer to compare the effects of standard dose (300 mg nocte) and high-dose (300 mg q.d.s.) ranitidine. Patients were assessed after 2 weeks of treatment and, if unhealed, after a further 2 weeks of therapy. The therapeutic gain in ulcer healing at the 2-week endoscopy of the higher dose over the lower dose of ranitidine was 22% (68% vs 46%, P less than 0.001). The cumulative ulcer healing rates at the 4-week endoscopy were 88% and 92% for the standard and high-dose ranitidine groups, respectively (N.S.). By 2 weeks, 61% of patients treated with standard ranitidine therapy and 79% of those receiving 300 mg ranitidine q.d.s. were pain-free (P less than 0.01). A further 2 weeks of therapy enabled 88% and 97% of patients (N.S.) to become pain-free on these two regimens, respectively. The drug regimens were equally well tolerated. Thus higher-dose ranitidine can significantly accelerate the healing of duodenal ulcer with improvement in pain relief.

The role of biological control of mosquitoes in integrated vector control.

An integrated approach for the control of mosquitoes and the diseases they transmit will better enable sustainable control while helping to circumvent some of the problems associated with the use of conventional insecticides. Environmental methods and biological control are alternatives to chemical control and are key components of the integrated strategy. The use of vertebrate and invertebrate predators and entomopathogens as biological control agents and their role in integrated control programs is reviewed with emphasis on fish, Toxorhynchites mosquitoes, Notonecta species, predatory copepods, entomopathogenic bacteria, and the fungus Lagenidium giganteum. The successful implementation of these organisms will depend on an in-depth understanding of the ecology of both the targeted species and the biological control agents to be used. Thorough geographic reconnaissance will also be essential for the successful abatement of pest and vector mosquitoes. The success and sustainability of future programs, especially in developing countries, will rely not only on the use of the most appropriate technologies but also on the direct participation of the affected communities. Possible undesirable effects of biological control are also reviewed.

Impact of zanamivir treatment on productivity, health status and healthcare resource use in patients with influenza. Zanamivir Study Group.

OBJECTIVE: This study examined the impact of zanamivir treatment on patient morbidity in patients with influenza. DESIGN AND SETTING: This was a multicentre, randomised, double-blind, parallel-group study conducted in 14 countries in Europe and North America during the winter of 1995/1996. PATIENTS AND PARTICIPANTS: The study included 722 individuals with virologically confirmed influenza. INTERVENTIONS: Two different zanamivir treatment regimens [twice daily (bid) or 4 times daily (qid) for 5 days] were compared with placebo. MAIN OUTCOME MEASURES AND RESULTS: Efficacy was measured using a number of patient-assessment questionnaires. Results showed that significantly fewer patients with influenza who were treated with zanamivir had additional contacts with healthcare professionals compared with those who received placebo (8 vs 14%; p < or = 0.049, bid and qid vs placebo). Individuals treated with zanamivir also spent fewer days absent from work (placebo: mean = 3.28 days; qid: mean = 2.52 days; p = 0.031) or college/school (placebo: mean = 2.90 days; bid: mean = 2.24 days; p = 0.032), and showed significant improvements in productivity compared with placebo. The health status questionnaire revealed significant improvements in patient well-being over the first 5 days of the study in those treated with zanamivir compared with those who received placebo. CONCLUSIONS: Zanamivir treatment reduced absenteeism, improved patient productivity and well-being, and reduced the additional use of healthcare resources in patients with influenza.

Preparing the woman with gestational diabetes for self-care. Use of a structured teaching plan by nursing staff.

Staff nurses are expected to teach patients with diabetes effectively, but studies indicate that nurses are often uncertain about determining the proper content to teach and the teaching methods to use. Evidence suggests that patients with gestational diabetes are crisis oriented and may have barriers to learning the necessary skills for self-care. To combat this problem, the authors developed the Structured Teaching Plan to guide staff nurses in teaching patients with gestational diabetes. This tool provides reinforcement of content and objective evaluation, thereby assisting the patient in overcoming learning barriers. This article reviews and outlines the components of the Structured Teaching Plan and its implementation and evaluation.

Entomopathogenic nematodes for control of diapausing codling moth (Lepidoptera: Tortricidae) in fruit bins.

Fruit bins infested with diapausing larvae of codling moth larvae, Cydia pomonella (L.), are a source of reinfestation of orchards and may jeopardize the success of mating disruption programs and other control strategies. Bins are not routinely treated for control of overwintering codling moth before placing them in orchards. Entomopathogenic nematodes provide a noninsecticidal alternative to methyl bromide that could be applied at the time bins are submerged in dump tanks at the packing house for flotation of fruit. Diapausing codling moth larvae in miniature fruit bins were highly susceptible to infective juveniles of Steinernema carpocapsae (Weiser). Immersion of bins in suspensions of S. carpocapsae ranging from 5 to 100 infective juveniles per milliliter of water resulted in 68-100% mortality. Immersion times of 1 or 5 min in suspensions with 5 infective juveniles of S. carpocapsae per milliliter of water, with and without Tween 80 (0.01%), yielded essentially the same mortality of codling moth larvae. Highest mortalities in codling moth larvae (88%) after treatment of bins in suspensions of 5 infective juveniles of S. carpocapsae per milliliter of water were observed after incubation for 24 h at 25 degrees C and 70% RH. Lowest mortalities (37%) were observed after incubation at 15 degrees C and 35% RH. Comparative tests conducted with Heterorhabditis marelatus Liu & Berry, Steinernema kraussei (Steiner), and S. carpocapsae with 5 infective juveniles per milliliter of water resulted in 21.7, 53.9, and 68.7% mortality, respectively. The use of miniature fruit bins as described in this article provides an effective means of assessing nematode efficacy without the cumbersome size of commercial bins.

Efficacy of granular formulations of Bacillus thuringiensis (H-14) for the control of Anopheles larvae in rice fields.

Three granular formulations of Bacillus thuringiensis (H-14) were applied to dense stands of maturing and mature rice for control of Anopheles crucians and An. quadrimaculatus. Aerial applications of the Vectobac granule (200 ITU/mg) at 5.6, 11.2 and 22.4 kg/ha to 0.4 ha plots resulted in 92, 94 and 96% reduction 48 hr after application, respectively, in populations predominantly consisting of late instars. The Bactimos granule (175 ITU/mg) was applied by aircraft to 0.4 ha plots and by a Cyclone seeder to 100 m2 plots at 2.8, 5.6 and 11.2 kg/ha, resulting in 100% reduction after 48 hr in natural populations of predominantly early instar larvae at all 3 rates with each type of application. Older instars confined to sentinel cages responded with 92, 98 and 100% mortality, respectively. Complete mortality was also observed at the same time in natural populations of predominantly young larvae in similar plots treated with Teknar granules (104 ITU/mg) at 1.7, 3.0 and 7.5 kg/ha. Near complete mortality (98-99%) was also observed in the older larvae used in the sentinel cages.

Efficacy of flowable concentrate formulations of Bacillus thuringiensis var. israelensis against black flies (Diptera:Simuliidae).

Seven flowable concentrate formulations of Bacillus thuringiensis (H-14), Teknar wdc, auto-dispersible Teknar, Teknar 2X aqueous concentrate, Teknar 2X oil base concentrate, Vectobac AS, Bactimos FC and Skeetal F, were evaluated in small streams against Simulium vittatum. There was no significant difference in efficacy among the formulations with the exception of the Teknar 2X aqueous concentrate, which required considerably less formulation (5 mg/liter/1 min) than the others to produce 95% mortality in penultimate instars of S. vittatum. The field determined LC-95 for the other formulations ranged from 10.6 to 15.9 mg/liter/1 min. There was no significant difference between the efficacy of excessively diluted and undiluted formulations.

Mosquito host range and field activity of Bacillus sphaericus isolate 2297 (serotype 25).

The 2297 isolate (serotype 25) of Bacillus sphaericus was bioassayed in the laboratory against 8 species of mosquitoes from 3 subfamilies. The most susceptible species were in the genus Culex and the least susceptible were the Aedes spp. and Toxorhynchites r. rutilus. Primary powders of the 2297 and 2362 (serotype 5a5b) isolates were evaluated in the field in natural and simulated habitats against Culex spp. The larvicidal activity of the two isolates was similar, with longer residual activity observed for both preparations in shaded shallow clear water. Larvicidal activity was curtailed in organically enriched and unshaded habitats. Isolate 2297 provided effective control for at least 1 week in an organically enriched habitat and for over 5 weeks in clear water in a shaded habitat when applied at the rate of 0.25 kg/ha.

Host range and selected factors influencing the mosquito larvicidal activity of the PG-14 isolate of Bacillus thuringiensis var. morrisoni.

Laboratory bioassay of the PG-14 isolate of Bacillus thuringiensis var. morrisoni (serotype 8a:8b) against early fourth instar larvae of 8 species of mosquitoes revealed a range of susceptibilities similar to the susceptibilities of these species to Bacillus thuringiensis var. israelensis (serotype 14). The most susceptible species were: Culex quinquefasciatus, Cx. salinarius, Anopheles albimanus and Aedes aegypti. The least susceptible species tested was An. quadrimaculatus. Separate bioassays of PG-14 against the four instars of Ae. aegypti demonstrated a strong negative correlation (R = -0.97) between larval age and susceptibility. Temperature significantly affected the stability of larvicidal toxin in aqueous suspensions of PG-14. Larvicidal activity of a bacterial suspension was nearly completely eliminated after 132 days of storage at 31 degrees C, but was essentially unchanged for those suspensions stored at 4 degrees C.

Beecomist-applied Bacillus sphaericus for the control of riceland mosquitoes.

An aerially applied flowable concentrate (FC) of Bacillus sphaericus Neide (isolate 2362) was evaluated against riceland mosquitoes using the Beecomist spray head. Application of the FC at 0.58 and 1.17 liter/ha in maturing rice fields resulted in a 48 hr mean posttreatment reduction of Anopheles quadrimaculatus of 71 and 82%, respectively. A significant reduction in larval populations one week posttreatment was also observed. Treatment rates of 0.29, 0.44, and 0.58 liter/ha in reflooded second crop rice fields resulted in 48 hr posttreatment reduction of Psorophora columbiae larvae of 50, 76 and 98% respectively.

Five new mosquito larvicidal strains of Bacillus sphaericus from non-mosquito origins.

Five new strains of Bacillus sphaericus having larvicidal activity similar to that of strains 1593 and 2362 are described. These strains were isolated from caterpillars or grasshoppers, but have no insecticidal activity toward these insects.

Natural occurrence of entomopathogenic nematodes (rhabditida: steinernema, heterorhabditis) in the azores.

A soil survey for entomopathogenic nematodes was conducted throughout the nine islands of the Azorean archipelago. Forty-six out of 1,180 samples (3.9%) were positive, with Heterorhabditis spp. isolated from 30 sites on six islands and Steinernema spp. isolated from 16 sites on three islands. São Miguel and Terceira Islands were positive for both genera, and Pico Island was positive only for Steinernema. Entomopathogenic nematodes were found from sea level up to 750 m. Seventy percent of the samples positive for Heterorhabditis were collected below 150 m, whereas 62.5% of the samples positive for Steinernema were collected above 300 m. Heterorhabditis was not isolated above 450 m. Steinernema was collected mostly in loamy-sand and sandy-loam soils with a pH below 6, whereas Heterorhabditis was mostly collected in sandy and loamy-sand soils with pH higher than 6. Steinernema and Heterorhabditis were found in cropland, orchards, and pastures, while Heterorhabditis was found also in woodland and native vegetation.

Association between illness progression measures and total cost in Alzheimer's disease.

OBJECTIVE: To compare the associations between dependence and clinical measures of cognition, function and behaviour and total care cost using data from a longitudinal study in Alzheimer's disease (AD). DESIGN: Longitudinal, observational study. SETTING: Community-dwelling subjects. PARTICIPANTS: Male and female subjects between 50 and 85 years of age with mild to moderate AD. INTERVENTION: None. MEASUREMENTS: Subject dependence was assessed using the Dependence Scale (DS), cognition (ADAS-Cog, MMSE), function (DAD), behaviour (NPI) and resource utilization with the Resource Utilization in Dementia Questionnaire. RESULTS: The repeated measures models confirmed a significant association between the DS and total care cost indicating an increase in cost with increasing dependence. A 1-unit increase in DS score was associated with a 28.60% increase in total care cost. Model 2 indicated that a one point change in MMSE, DAD and NPI is associated with 5.29%, 2.32% and 1.71% increase in total cost, respectively. Model 3 indicated that a one point change in ADAS-Cog, DAD and NPI is associated with a 1.74%, 2.42%and 1.62% increase in total cost, respectively. CONCLUSION: Strategies which prevent deterioration in clinical measures or delay dependence should result in total cost savings. The quantitative relationships observed should assist in the economic assessment of interventions which effect cognition, function, behaviour and dependence.