Extensive human-mediated jump dispersal within and across the native and introduced ranges of the invasive termite Reticulitermes flavipes.

As native ranges are often geographically structured, invasive species originating from a single source population only carry a fraction of the genetic diversity present in their native range. The invasion process is thus often associated with a drastic loss of genetic diversity resulting from a founder event. However, the fraction of diversity brought to the invasive range may vary under different invasion histories, increasing with the size of the propagule, the number of reintroduction events, and/or the total genetic diversity represented by the various source populations in a multiple-introduction scenario. In this study, we generated a SNP data set for the invasive termite Reticulitermes flavipes from 23 native populations in the eastern United States and six introduced populations throughout the world. Using population genetic analyses and approximate Bayesian computation random forest, we investigated its worldwide invasion history. We found a complex invasion pathway with multiple events out of the native range and bridgehead introductions from the introduced population in France. Our data suggest that extensive long-distance jump dispersal appears common in both the native and introduced ranges of this species, probably through human transportation. Overall, our results show that similar to multiple introduction events into the invasive range, admixture in the native range prior to invasion can potentially favour invasion success by increasing the genetic diversity that is later transferred to the introduced range.

Alteration of gut microbiota with a broad-spectrum antibiotic does not impair maternal care in the European earwig.

The microbes residing within the gut of an animal host often increase their own fitness by modifying their host's physiological, reproductive and behavioural functions. Whereas recent studies suggest that they may also shape host sociality and therefore have critical effects on animal social evolution, the impact of the gut microbiota on maternal care remains unexplored. This is surprising, as this behaviour is widespread among animals, often determines the fitness of both juveniles and parents, and is essential in the evolution of complex animal societies. Here, we tested whether life-long alterations of the gut microbiota with rifampicin-a broad-spectrum antibiotic-impair pre- and post-hatching maternal care in the European earwig. Our results first confirm that rifampicin altered the mothers' gut microbial communities and indicate that the composition of the gut microbiota differs before and after egg care. Contrary to our predictions, however, the rifampicin-induced alterations of the gut microbiota did not modify pre- or post-hatching care. Independent of maternal care, rifampicin increased the females' faeces production and resulted in lighter eggs and juveniles. By contrast, rifampicin altered none of the other 21 physiological, reproductive and longevity traits measured over the 300 days of a female's lifetime. Overall, these findings reveal that altering the gut microbiota with a large spectrum antibiotic such as rifampicin does not necessarily affect host sociality. They also emphasize that not all animals have evolved a co-dependence with their microbiota and call for caution when generalizing the central role of gut microbes in host biology.

Strong Gene Flow Undermines Local Adaptations in a Host Parasite System.

The co-evolutionary pathways followed by hosts and parasites strongly depend on the adaptive potential of antagonists and its underlying genetic architecture. Geographically structured populations of interacting species often experience local differences in the strength of reciprocal selection pressures, which can result in a geographic mosaic of co-evolution. One example of such a system is the boreo-montane social wasp Polistes biglumis and its social parasite Polistes atrimandibularis, which have evolved local defense and counter-defense mechanisms to match their antagonist. In this work, we study spatial genetic structure of P. biglumis and P. atrimandibularis populations at local and regional scales in the Alps, by using nuclear markers (DNA microsatellites, AFLP) and mitochondrial sequences. Both the host and the parasite populations harbored similar amounts of genetic variation. Host populations were not genetically structured at the local scale, but geographic regions were significantly differentiated from each other in both the host and the parasite in all markers. The net dispersal inferred from genetic differentiation was similar in the host and the parasite, which may be due to the annual migration pattern of the parasites between alpine and lowland populations. Thus, the apparent dispersal barriers (i.e., high mountains) do not restrict gene flow as expected and there are no important gene flow differences between the species, which contradict the hypothesis that restricted gene flow is required for local adaptations to evolve.

Efficient but occasionally imperfect vertical transmission of gut mutualistic protists in a wood-feeding termite.

Although mutualistic associations between animals and microbial symbionts are widespread in nature, the mechanisms that have promoted their evolutionary persistence remain poorly understood. A vertical mode of symbiont transmission (from parents to offspring) is thought to ensure partner fidelity and stabilization, although the efficiency of vertical transmission has rarely been investigated, especially in cases where hosts harbour a diverse microbial community. Here we evaluated vertical transmission rates of cellulolytic gut oxymonad and parabasalid protists in the wood-feeding termite Reticulitermes grassei. We sequenced amplicons of the 18S rRNA gene of protists from 24 colonies of R. grassei collected in two populations. For each colony, the protist community was characterized from the gut of 14 swarming reproductives and from a pool of 10 worker guts. A total of 98 operational taxonomic units belonging to 13 species-level taxa were found. The vertical transmission rate was estimated for each protist present in a colony based on its frequency among the reproductives. The results revealed that transmission rates were high, with an average of 0.897 (±0.164) per protist species. Overall, the protist community did not differ between reproductive sexes, suggesting that both the queen and the king could contribute to the gut microbiota of the offspring. A positive relationship between the transmission rate of protists and their prevalence within populations was also detected. However, transmission rates alone do not explain the prevalence of protists. In conclusion, these findings reveal key forces behind a conserved, multispecies mutualism, raising further questions on the roles of horizontal transfer and negative selection in shaping symbiont prevalence.

Invasion Dynamics of A Termite, Reticulitermes flavipes, at Different Spatial Scales in France.

Termites are social insects that can also be major pests. A well-known problem species is the subterranean termite, Reticulitermes flavipes. It is invasive in France and is thought to have arrived from Louisiana during the 18th century. While the putative source of French populations has been identified, little is known about how the termite spread following its establishment. Here, we examined expansion patterns at different spatial scales in urban areas to clarify how R. flavipes spread in France. Based on our analyses of phylogeography and population genetics, results suggest a scenario of successive introductions into the Charente-Maritime region, on the Atlantic Coast. Two major expansion fronts formed: one that spread toward the northeast and the other toward the southeast. At the regional scale, different spatial and genetic distribution patterns were observed: there was heterogeneity in Île-de-France and aggregation in Centre-Val de Loire. At the local scale, we found that our three focal urban sites each formed a single large colony that contained several secondary reproductives. Our findings represent a second step in efforts to reconstruct termite's invasion dynamics. They also highlight the role that may have been played by the French railway network in transporting termites over long distances.

Unbalanced biparental care during colony foundation in two subterranean termites.

Parental care is a major component of reproduction in social organisms, particularly during the foundation steps. Because investment into parental care is often costly, each parent is predicted to maximize its fitness by providing less care than its partner. However, this sexual conflict is expected to be low in species with lifelong monogamy, because the fitness of each parent is typically tied to the other's input. Somewhat surprisingly, the outcomes of this tug-of-war between maternal and paternal investments have received important attention in vertebrate species, but remain less known in invertebrates. In this study, we investigated how queens and kings share their investment into parental care and other social interactions during colony foundation in two termites with lifelong monogamy: the invasive species Reticulitermes flavipes and the native species R. grassei. Behaviors of royal pairs were recorded during six months using a non-invasive approach. Our results showed that queens and kings exhibit unbalanced investment in terms of grooming, antennation, trophallaxis, and vibration behavior. Moreover, both parents show behavioral differences toward their partner or their descendants. Our results also revealed differences among species, with R. flavipes exhibiting shorter periods of grooming and antennation toward eggs or partners. They also did more stomodeal trophallaxis and less vibration behavior. Overall, this study emphasizes that despite lifelong monogamy, the two parents are not equally involved in the measured forms of parental care and suggests that kings might be specialized in other tasks. It also indicates that males could play a central, yet poorly studied role in the evolution and maintenance of the eusocial organization.

Origin and distribution of desert ants across the Gibraltar Straits.

The creation of geographic barriers has long been suspected to contribute to the formation of new species. We investigated the phylogeography of desert ants in the western Mediterranean basin in order to elucidate their mode of diversification. These insects which have a low dispersal capacity are recently becoming important model systems in evolutionary studies. We conducted an extensive sampling of species belonging to the Cataglyphis albicans group in the Iberian Peninsula (IP) and the northern Morocco (North Africa; NA). We then combined genetic, chemical and morphological analyses. The results suggest the existence of at least three and five clades in the IP and NA, respectively, whose delineation partially encompass current taxonomic classification. The three Iberian clades are monophyletic, but their origin in NA is uncertain (79% and 22% for Bayesian and Maximum Likelihood support, respectively). The estimation of divergence time suggests that a speciation process was initiated after the last reopening of the Gibraltar Straits ≈5.33 Ma. In the IP, the clades are parapatric and their formation may have been triggered by the fragmentation of a large population during the Pleistocene due to extended periods of glaciation. This scenario is supported by demographic analyses pointing at a recent expansion of Iberian populations that contrasts with the progressive contraction of the NA clades. Niche modeling reveals that this area, governed by favorable climatic conditions for desert ants, has recently increased in the IP and decreased in NA. Altogether, our data points at geoclimatic events as major determinants of species formation in desert ants, reinforcing the role of allopatric speciation.

An American termite in Paris: temporal colony dynamics.

Termites of the genus Reticulitermes are widespread invaders, particularly in urban habitats. Their cryptic and subterranean lifestyle makes them difficult to detect, and we know little about their colony dynamics over time. In this study we examined the persistence of Reticulitermes flavipes (Kollar) colonies in the city of Paris over a period of 15 years. The aim was (1) to define the boundaries of colonies sampled within the same four areas over two sampling periods, (2) to determine whether the colonies identified during the first sampling period persisted to the second sampling period, and (3) to compare the results obtained when colonies were delineated using a standard population genetic approach versus a Bayesian clustering method that combined both spatial and genetic information. Herein, colony delineations were inferred from genetic differences at nine microsatellite loci and one mitochondrial locus. Four of the 18 identified colonies did not show significant differences in their genotype distributions between the two sampling periods. While allelic richness was low, making it hard to reliably distinguish colony family type, most colonies appeared to retain the same breeding structure over time. These large and expansive colonies showed an important ability to fuse (39% were mixed-family colonies), contained hundreds of reproductives and displayed evidence of isolation-by-distance, suggesting budding dispersal. These traits, which favor colony persistence over time, present a challenge for pest control efforts, which apply treatment locally. The other colonies showed significant differences, but we cannot exclude the possibility that their genotype distributions simply changed over time.

Cognitive-behaviour therapy for health anxiety in medical patients (CHAMP): a randomised controlled trial with outcomes to 5 years.

BACKGROUND: Health anxiety is an under-recognised but frequent cause of distress that is potentially treatable, but there are few studies in secondary care. OBJECTIVE: To determine the clinical effectiveness and cost-effectiveness of a modified form of cognitive-behaviour therapy (CBT) for health anxiety (CBT-HA) compared with standard care in medical outpatients. DESIGN: Randomised controlled trial. SETTING: Five general hospitals in London, Middlesex and Nottinghamshire. PARTICIPANTS: A total of 444 patients aged 16-75 years seen in cardiology, endocrinology, gastroenterology, neurology and respiratory medicine clinics who scored ≥ 20 points on the Health Anxiety Inventory (HAI) and satisfied diagnostic requirements for hypochondriasis. Those with current psychiatric disorders were excluded, but those with concurrent medical illnesses were not. INTERVENTIONS: Cognitive-behaviour therapy for health anxiety - between 4 and 10 1-hour sessions of CBT-HA from a health professional or psychologist trained in the treatment. Standard care was normal practice in primary and secondary care. MAIN OUTCOME MEASURES: Primary - researchers masked to allocation assessed patients at baseline, 3, 6, 12, 24 months and 5 years. The primary outcome was change in the HAI score between baseline and 12 months. Main secondary outcomes - costs of care in the two groups after 24 and 60 months, change in health anxiety (HAI), generalised anxiety and depression [Hospital Anxiety and Depression Scale (HADS)] scores, social functioning using the Social Functioning Questionnaire and quality of life using the EuroQol-5 Dimensions (EQ-5D), at 6, 12, 24 and 60 months, and deaths over 5 years. RESULTS: Of the 28,991 patients screened over 21 months, 5769 had HAI scores of ≥ 20 points. Improvement in HAI scores at 3 months was significantly greater in the CBT-HA group (mean number of sessions = 6) than in the standard care, and this was maintained over the 5-year period (overall p < 0.0001), with no loss of efficacy between 2 and 5 years. Differences in the generalised anxiety (p = 0.0018) and depression scores (p = 0.0065) on the HADS were similar in both groups over the 5-year period. Gastroenterology and cardiology patients showed the greatest CBT gains. The outcomes for nurses were superior to those of other therapists. Deaths (n = 24) were similar in both groups; those in standard care died earlier than those in CBT-HA. Patients with mild personality disturbance and higher dependence levels had the best outcome with CBT-HA. Total costs were similar in both groups over the 5-year period (£12,590.58 for CBT-HA; £13,334.94 for standard care). CBT-HA was not cost-effective in terms of quality-adjusted life-years, as measured using the EQ-5D, but was cost-effective in terms of HAI outcomes, and offset the cost of treatment. LIMITATIONS: Many eligible patients were not randomised and the population treated may not be representative. CONCLUSIONS: CBT-HA is a highly effective treatment for pathological health anxiety with lasting benefit over 5 years. It also improves generalised anxiety and depressive symptoms more than standard care. The presence of personality abnormality is not a bar to successful outcome. CBT-HA may also be cost-effective, but the high costs of concurrent medical illnesses obscure potential savings. This treatment deserves further research in medical settings. TRIAL REGISTRATION: Current Controlled Trials ISRCTN14565822. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 21, No. 50. See the NIHR Journals Library website for further project information.

Subterranean termite phylogeography reveals multiple postglacial colonization events in southwestern Europe.

A long-standing goal of evolutionary biology is to understand how paleoclimatic and geological events shape the geographical distribution and genetic structure within and among species. Using a diverse set of markers (cuticular hydrocarbons, mitochondrial and nuclear gene sequences, microsatellite loci), we studied Reticulitermes grassei and R. banyulensis, two closely related termite species in southwestern Europe. We sought to clarify the current genetic structure of populations that formed following postglacial dispersal from refugia in southern Spain and characterize the gene flow between the two lineages over the last several million years. Each marker type separately provided a fragmented picture of the evolutionary history at different timescales. Chemical analyses of cuticular hydrocarbons and phylogenetic analyses of mitochondrial and nuclear genes showed clear separation between the species, suggesting they diverged following vicariance events in the Late Miocene. However, the presence of intermediate chemical profiles and mtDNA introgression in some Spanish colonies suggests ongoing gene flow. The current genetic structure of Iberian populations is consistent with alternating isolation and dispersal events during Quaternary glacial periods. Analyses of population genetic structure revealed postglacial colonization routes from southern Spain to France, where populations underwent strong genetic bottlenecks after traversing the Pyrenees resulting in parapatric speciation.

Historical biogeography of Reticulitermes termites (Isoptera: Rhinotermitidae) inferred from analyses of mitochondrial and nuclear loci.

Termites of the genus Reticulitermes are ecologically and economically important wood-feeding social insects that are widespread in the Holarctic region. Despite their importance, no study has yet attempted to reconstruct a global time-scaled phylogeny of Reticulitermes termites. In this study, we sequenced mitochondrial (2096bp) and nuclear (829bp) loci from 61 Reticulitermes specimens, collected across the genus' entire range, and one specimen of Coptotermes formosanus, which served as an outgroup. Bayesian and Maximum likelihood analyses conducted on the mitochondrial and nuclear sequences support the existence of four main lineages that span four global geographical regions: North America (NA lineage), western Europe (WE lineage), a region including eastern Europe and western Asia (EA+WA lineage), and eastern Asia (EA lineage). The mitochondrial data allowed us to clarify the phylogenetic relationships among these lineages. They were also used to infer a chronogram that was time scaled based on age estimates for termite fossils (including the oldest Reticulitermes fossils, which date back to the late Eocene-early Oligocene). Our results support the hypothesis that the extant Reticulitermes lineage first differentiated in North America. The first divergence event in the ancestral lineage of Reticulitermes occurred in the early Miocene and separated the Nearctic lineages (i.e., the NA lineages) from the Palearctic lineages (i.e., WE, EE+WA, and EA lineages). Our analyses revealed that the main lineages of Reticulitermes diversified because of vicariance and migration events, which were probably induced by major paleogeographic and paleoclimatic changes that occurred during the Cenozoic era. This is the first global and comprehensive phylogenetic study of Reticulitermes termites, and it provides a crucial foundation for studying the evolution of phenotypic and life-history traits in Reticulitermes. For instance, the phylogeny we obtained suggested that 'asexual queen succession', a unique reproductive system, independently evolved at least three times during the diversification of the genus.

Spatial structuring of the population genetics of a European subterranean termite species.

In population genetics studies, detecting and quantifying the distribution of genetic variation can help elucidate ecological and evolutionary processes. In social insects, the distribution of population-level genetic variability is generally linked to colony-level genetic structure. It is thus especially crucial to conduct complementary analyses on such organisms to examine how spatial and social constraints interact to shape patterns of intraspecific diversity. In this study, we sequenced the mitochondrial COII gene for 52 colonies of the subterranean termite Reticulitermes grassei (Isoptera: Rhinotermitidae), sampled from a population in southwestern France. Three haplotypes were detected, one of which was found exclusively in the southern part of the study area (near the Pyrenees). After genotyping 6 microsatellite loci for 512 individual termites, we detected a significant degree of isolation by distance among individuals over the entire range; however, the cline of genetic differentiation was not continuous, suggesting the existence of differentiated populations. A spatial principal component analysis based on allele frequency data revealed significant spatial autocorrelation among genotypes: the northern and southern groups were strongly differentiated. This finding was corroborated by clustering analyses; depending on the randomized data set, two or three clusters, exhibiting significant degrees of differentiation, were identified. An examination of colony breeding systems showed that colonies containing related neotenic reproductives were prevalent, suggesting that inbreeding may contribute to the high level of homozygosity observed and thus enhance genetic contrasts among colonies. We discuss the effect of evolutionary and environmental factors as well as reproductive and dispersal modes on population genetic structure.

Population diversity in cuticular hydrocarbons and mtDNA in a mountain social wasp.

Nestmate recognition is a common phenomenon in social insects that typically is mediated by cuticular hydrocarbons. Geographical variation in cuticular hydrocarbons has been observed, although the pattern of variation is not consistent across species and is usually related to the biology and ecology of the different species. Polistes biglumis (Hymenoptera: Vespidae) is a social wasp that lives in high mountains where populations are separated by significant geographical barriers. Here we investigated the level of chemical variation among populations of P. biglumis in the Alps, and shed light on the phylogeography of this species. Populations could be discriminated by means of their cuticular hydrocarbon profiles, which showed a pattern consistent with the isolation-by-distance hypothesis. Molecular data highlighted two areas with different levels of haplotype diversity, although all wasps belonged to the same species. These results suggest that the populations of P. biglumis in the Alps are geographically isolated from one another, favoring their genetic and chemical differentiation.

Therapist differences in a randomised trial of the outcome of cognitive behaviour therapy for health anxiety in medical patients.

BACKGROUND: Health anxiety is common in medical settings and can be treated successfully by cognitive behaviour therapy. However it is not clear who might be best placed to deliver this therapy. OBJECTIVES: In a planned secondary analysis of data from a randomised trial of adapted cognitive behaviour therapy for health anxiety we compared outcomes of therapy delivered by nurses and other professional groups. DESIGN: A randomised controlled trial with two treatment arms, 5-10 sessions of cognitive behaviour therapy adapted health anxiety or standard care. SETTING: Cardiology, endocrine, gastroenterology, neurological and respiratory clinics in six general hospitals in the UK covering urban, suburban and rural areas. PARTICIPANTS: Medical patients attending the clinics who had pathological health anxiety and also scored for a diagnosis of hypochondriasis. METHODS: Patients were randomised to one of two treatment arms, 5-10 sessions of cognitive behaviour therapy adapted health anxiety or standard care delivered by naive therapists (not randomised) who were trained in advance before delivering the treatment. Independent assessment of outcomes by researchers masked to allocation status at 3m, 6m, 12m and 24m. RESULTS: 444 patients were randomised in the trial, 219 to cognitive behaviour therapy adapted health anxiety and 225 to standard care. 373 (84%) completed assessments after two years. Those treated by nurses (n=66) had improvement in health anxiety, generalised anxiety and depression outcomes that were significantly better and twice as great as those of the professional groups of assistant psychologists (n=87) and graduate workers (n=66) (P<0.01 over all time points). The number needed to treat to show superiority of nurse-delivered treatment over other treatment delivery was 4 at 6 months and 6 at one year. CONCLUSION: General nurses, after suitable training, are very effective therapists for patients with health anxiety in medical clinics and should be the therapists of choice for patients in these settings.

'The COPD breathlessness manual': a randomised controlled trial to test a cognitive-behavioural manual versus information booklets on health service use, mood and health status, in patients with chronic obstructive pulmonary disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a costly long-term condition associated with frequent Accident and Emergency (A&E) and hospital admissions. Psychological difficulties and inadequate self-management can amplify this picture. AIMS: To compare a cognitive-behavioural manual versus information booklets (IB) on health service use, mood and health status. METHODS: Two hundred and twenty-two COPD patients were randomly allocated to receive either the COPD breathlessness manual (CM) or IB. They were instructed to work through their programme at home, over 5 weeks. Guidance from a facilitator was provided at an initial home visit plus two telephone call follow-ups. RESULTS: After 12 months, total A&E visits had reduced by 42% in the CM group, compared with a 16% rise in the IB group. The odds of people in the IB group attending A&E 12 months post-intervention was 1.9 times higher than for the CM group (CI 1.05-3.53). Reduction in hospital admissions and bed days were greatest in the CM group. At 6 months, there were significantly greater improvements in anxiety (F (2,198)=5.612, P=0.004), depression (F (1.8,176.1)=10.697, P⩽0.001) and dyspnoea (F (2,198)=18.170, P⩽0.001) in the CM group. Estimated savings at 12 months were greatest in the CM group, amounting to £30k or £270 per participant. CONCLUSION: The COPD manual, which addresses physical and mental health, is a straightforward cost-effective intervention that is worth offering to COPD patients within primary or secondary care.

Clinical and cost-effectiveness of cognitive behaviour therapy for health anxiety in medical patients: a multicentre randomised controlled trial.

BACKGROUND: Health anxiety has been treated by therapists expert in cognitive behaviour therapy with some specific benefit in some patients referred to psychological services. Those in hospital care have been less often investigated. Following a pilot trial suggesting efficacy we carried out a randomised study in hospital medical clinics. METHODS: We undertook a multicentre, randomised trial on health anxious patients attending cardiac, endocrine, gastroenterological, neurological, and respiratory medicine clinics in secondary care. We included those aged 16-75 years, who satisfied the criteria for excessive health anxiety, and were resident in the area covered by the hospital, were not under investigation for new pathology or too medically unwell to take part. We used a computer-generated random scheme to allocate eligible medical patients to an active treatment group of five-to-ten sessions of adapted cognitive behaviour therapy (CBT-HA group) delivered by hospital-based therapists or to standard care in the clinics. The primary outcome was change in health anxiety symptoms measured by the Health Anxiety Inventory at 1 year and the main secondary hypothesis was equivalence of total health and social care costs over 2 years, with an equivalence margin of £150. Analysis was by intention to treat. The study is registered with controlled-trials.com, ISRCTN14565822. FINDINGS: Of 28,991 patients screened, 444 were randomly assigned to receive either adapted cognitive behaviour therapy (CBT-HA group, 219 participants) or standard care (standard care group, 225), with 205 participants in the CBT-HA group and 212 in the standard care group included in the analyses of the primary endpoints. At 1 year, improvement in health anxiety in the patients in the CBT-HA group was 2·98 points greater than in those in the standard care group (95% CI 1·64-4·33, p<0·0001), and twice as many patients receiving cognitive behaviour therapy achieved normal levels of health anxiety compared with those in the control group (13·9% vs 7·3%; odds ratio 2·15, 95% CI 1·09-4·23, p=0·0273). Similar differences were observed at 6 months and 2 years, and there were concomitant reductions in generalised anxiety and, to a lesser extent, depression. Of nine deaths, six were in the control group; all were due to pre-existing illness. Social functioning or health-related quality of life did not differ significantly between groups. Equivalence in total 2-year costs was not achieved, but the difference was not significant (adjusted mean difference £156, 95% CI -1446 to 1758, p=0·848). INTERPRETATION: This form of adapted cognitive behaviour therapy for health anxiety led to sustained symptomatic benefit over 2 years, with no significant effect on total costs. It deserves wider application in medical care. FUNDING: National Institute for Health Research Health Technology Assessment Programme.

Colony breeding structure of the invasive termite Reticulitermes urbis (Isoptera: Rhinotermitidae).

Invasive species cause severe environmental and economic problems. The invasive success of social insects often appears to be related to their ability to adjust their social organization to new environments. To gain a better understanding of the biology of invasive termites, this study investigated the social organization of the subterranean termite, Reticulitermes urbis, analyzing the breeding structure and the number of reproductives within colonies from three introduced populations. By using eight microsatellite loci to determine the genetic structure, it was found that all the colonies from the three populations were headed by both primary reproductives (kings and queens) and secondary reproductives (neotenics) to form extended-family colonies. R. urbis appears to be the only Reticulitermes species with a social organization based solely on extended-families in both native and introduced populations, suggesting that there is no change in their social organization on introduction. F-statistics indicated that there were few neotenics within the colonies from urban areas, which did not agree with results from previous studies and field observations. This suggests that although several neotenics may be produced, only few become active reproductives. The results also imply that the invasive success of R. urbis may be based on different reproductive strategies in urban and semiurbanized areas. The factors influencing an individual to differentiate into a neotenic in Reticulitermes species are discussed.

Prevalence of health anxiety problems in medical clinics.

OBJECTIVES: To determine the prevalence of significant health anxiety (hypochondriasis) in patients aged 16-75 in cardiology, respiratory medicine, neurological, endocrine and gastrointestinal clinics in general hospitals in London, Middlesex and North Nottinghamshire. METHOD: The Health Anxiety Inventory (HAI) (short form) was administered to patients attending the five clinics over a 21 month period and all those who scored 20 or more invited to take part in a further assessment for a randomised controlled trial. RESULTS: Of 43,205 patients attending the clinics 28,991 (67.1%) were assessed and of these, after exclusion of ineligible patients 5747 (19.8%) had significant health anxiety. 444 subsequently agreed to take part in a randomised controlled trial of treatment. The prevalence levels varied by clinic with neurology (24.7%) having the highest prevalence followed by respiratory medicine (20.9%), gastroenterology (19.5%), cardiology (19.1%), and endocrinology (17.5%). CONCLUSION: Abnormal health anxiety is common and a significant problem in those attending medical clinics and deserves greater awareness.

CHAMP: Cognitive behaviour therapy for health anxiety in medical patients, a randomised controlled trial.

BACKGROUND: Abnormal health anxiety, also called hypochondriasis, has been successfully treated by cognitive behaviour therapy (CBT) in patients recruited from primary care, but only one pilot trial has been carried out among those attending secondary medical clinics where health anxiety is likely to be more common and have a greater impact on services. The CHAMP study extends this work to examine both the clinical and cost effectiveness of CBT in this population. METHOD/DESIGN: The study is a randomized controlled trial with two parallel arms and equal randomization of 466 eligible patients (assuming a 20% drop-out) to an active treatment group of 5-10 sessions of cognitive behaviour therapy and to a control group. The aim at baseline, after completion of all assessments but before randomization, was to give a standard simple explanation of the nature of health anxiety for all participants. Subsequently the control group was to receive whatever care might usually be available in the clinics, which is normally a combination of clinical assessment, appropriate tests and reassurance. Those allocated to the active treatment group were planned to receive between 5 and 10 sessions of an adapted form of cognitive behaviour therapy based on the Salkovskis/Warwick model, in which a set of treatment strategies are chosen aimed at helping patients understand the factors that drive and maintain health anxiety. The therapy was planned to be given by graduate research workers, nurses or other health professionals trained for this intervention whom would also have their competence assessed independently during the course of treatment. The primary outcome is reduction in health anxiety symptoms after one year and the main secondary outcome is the cost of care after two years. DISCUSSION: This represents the first trial of adapted cognitive behaviour therapy in health anxiety that is large enough to test not only the clinical benefits of treatment but also whether the cost of treatment is offset by savings from reduced use of other health services in comparison to the control group.Cognitive behaviour therapy for Health Anxiety in Medical Patients (CHAMP) TRIAL REGISTRATION: Current Controlled Trials ISRCTN14565822.