The impact of health technologies may extend beyond the patient and affect the health of people in their network, like their informal carers. The National Institute for Health and Care Excellence (NICE) methods guide explicitly allows the inclusion of health-related quality of life (HRQoL) effects on carers in economic evaluations when these effects are substantial, but the proportion of NICE appraisals that includes carer HRQoL remains small. This paper discusses when inclusion of carer HRQoL is justified, how inclusion can be substantiated, and how carer HRQoL can be measured and included in health economic models. Inclusion of HRQoL in economic evaluations can best be substantiated by data collected in (carers for) patients eligible for receiving the intervention. To facilitate combining patient and carer utilities on the benefit side of economic evaluations, using EQ-5D to measure impacts on carers seems the most successful strategy in the UK context. Alternatives to primary data collection of EQ-5D include vignette studies, using existing values, and mapping algorithms. Carer HRQoL was most often incorporated in economic models in NICE appraisals by employing (dis)utilities as a function of the patient's health state or disease severity. For consistency and comparability, economic evaluations including carer HRQoL should present analyses with and without carer HRQoL.

This study focuses on the transformational leadership-work engagement relationship by investigating resource and demand pathways for daily off-work recovery and employee wellbeing (EWB). While previous research highlighted how transformational leadership energizes employees to engage at work, energy is a finite resource requiring daily restoration for EWB. Yet, how the leader’s energizing effect relates to daily employees’ recovery remains unknown. Following job demands-resource-recovery theory, we test two pathways that relate the transformational leadership-work engagement relationship to daily employee recovery: (a) Resource-based via resource-building, (b) demand-based via increased demands. Utilizing a 10-day, two daily measurement (N = 88) study, multilevel path analyses revealed: transformational leadership predicted via work engagement (b = .17, p < .05) role clarity (b = .56, p < .01), then positive (b = .39, p < .01), and negative work-nonwork spillover (b = –.38, p < .01). Positive work-nonwork spillover predicted recovery positively (b = .25, p < .01), negative work-nonwork spillover negatively (b = –.40, p < .01). Recovery predicted EWB for positive (b = .38, p < .01) and for negative (b = –.43, p < .01) affect. Work engagement predicted workload (b = .35, p < .01), further negative (b = .33, p < .01) and positive work-nonwork spillover (b = –.16, p < .01), hampering EWB. As one pathway effect might cancel the other, the main effect of transformational leadership on EWB was not significant in the integrative model (p > .05). Results highlight dark and bright sides of the transformational leadership-work engagement relationship regarding daily recovery.

The anthropogenic spread of disease from captive to wild amphibian populations (referred to as spillover) is linked to global amphibian declines. Disinfecting procedures and protocols exist to mitigate pathogen transmission to and within natural areas, but understanding of visitor attitudes and behaviour regarding their adoption is limited. We surveyed visitors in two natural areas in a global amphibian biodiversity hotspot to assess their attitudes regarding pathogen spread in such areas and analysed the factors influencing their behavioural intentions to take specific actions to prevent pathogen spillover. Visitors’ willingness to take action was influenced by their attitudes, behavioural control and trust in wildlife/land managers, whereas socio-demographic characteristics were less influential. These findings help us to understand visitor behaviour with respect to amphibian biosecurity in natural areas and inform enhanced biosecurity measures and strategic messaging to reduce pathogen spillover.

We developed an agent-based model using a trial emulation approach to quantify effect measure modification of spillover effects of pre-exposure prophylaxis (PrEP) for HIV among men who have sex with men (MSM) in the Atlanta-Sandy Springs-Roswell metropolitan area, Georgia. PrEP may impact not only the individual prescribed, but also their partners and beyond, known as spillover. We simulated a two-stage randomised trial with eligible components (≥3 agents with ≥1 HIV+ agent) first randomised to intervention or control (no PrEP). Within intervention components, agents were randomised to PrEP with coverage of 70%, providing insight into a high PrEP coverage strategy. We evaluated effect modification by component-level characteristics and estimated spillover effects on HIV incidence using an extension of randomisation-based estimators. We observed an attenuation of the spillover effect when agents were in components with a higher prevalence of either drug use or bridging potential (if an agent acts as a mediator between ≥2 connected groups of agents). The estimated spillover effects were larger in magnitude among components with either higher HIV prevalence or greater density (number of existing partnerships compared to all possible partnerships). Consideration of effect modification is important when evaluating the spillover of PrEP among MSM.

Genetic variation in parasites has important consequences for host–parasite interactions. Prior studies of the ecologically important parasite Metschnikowia bicuspidata have suggested low genetic variation in the species. Here, we collected M. bicuspidata from two host species (Daphnia dentifera and Ceriodaphnia dubia) and two regions (Michigan and Indiana, USA). Within a lake, outbreaks tended to occur in one host species but not the other. Using microsatellite markers, we identified six parasite genotypes grouped within three distinct clades, one of which was rare. Of the two main clades, one was generally associated with D. dentifera, with lakes in both regions containing a single genotype. The other M. bicuspidata clade was mainly associated with C. dubia, with a different genotype dominating in each region. Despite these associations, both D. dentifera- and C. dubia-associated genotypes were found infecting both hosts in lakes. However, in lab experiments, the D. dentifera-associated genotype infected both D. dentifera and C. dubia, but the C. dubia-associated genotype, which had spores that were approximately 30% smaller, did not infect D. dentifera. We hypothesize that variation in spore size might help explain patterns of cross-species transmission. Future studies exploring the causes and consequences of variation in spore size may help explain patterns of infection and the maintenance of genotypic diversity in this ecologically important system.

Maize production is central to rural livelihoods in the hills of Nepal. Access to affordable improved maize seed has long been a barrier to productivity gains and livelihood improvement. This study evaluates the direct and indirect (spillover) impacts of a community-based seed production program in Nepal using a quasi-experimental method for selected outcome indicators. Our results show that community-based seed production provides a significant positive direct impact on maize income and female leadership opportunities. The impacts were particularly favorable for disadvantaged households (HHs) from lower castes and HHs that owned less land. There is also strong evidence of spillover impacts on improved seed adoption, yield, and household maize self-sufficiency. Community-based seed production thereby could help Nepal attain cereal self-sufficiency and nutritional security as envisioned in the national agricultural development strategy and seed vision.

In developing countries, estimates of the prevalence and diversity of Leptospira infections in livestock, an important but neglected zoonotic pathogen and cause of livestock productivity loss, are lacking. In Madagascar, abattoir sampling of cattle and pigs demonstrated a prevalence of infection of 20% in cattle and 5% in pigs by real-time PCR. In cattle, amplification and sequencing of the Leptospira-specific lfb1 gene revealed novel genotypes, mixed infections of two or more Leptospira species and evidence for potential transmission between small mammals and cattle. Sequencing of the secY gene demonstrated genetic similarities between Leptospira detected in Madagascar and, as yet, uncultured Leptospira strains identified in Tanzania, Reunion and Brazil. Detection of Leptospira DNA in the same animal was more likely in urine samples or pooled samples from four kidney lobes relative to samples collected from a single kidney lobe, suggesting an effect of sampling method on detection. In pigs, no molecular typing of positive samples was possible. Further research into the epidemiology of livestock leptospirosis in developing countries is needed to inform efforts to reduce human infections and to improve livestock productivity.

Pathogen spillover from wildlife to humans or domestic animals requires a series of conditions to align with space and time. Comparing these conditions between times and locations where spillover does and does not occur presents opportunities to understand the factors that shape spillover risk. Bovine rabies transmitted by vampire bats was first confirmed in 1911 and has since been detected across the distribution of vampire bats. However, Uruguay is an exception. Uruguay was free of bovine rabies until 2007, despite high-cattle densities, the presence of vampire bats and a strong surveillance system. To explore why Uruguay was free of bovine rabies until recently, we review the historic literature and reconstruct the conditions that would allow rabies invasion into Uruguay. We used available historical records on the abundance of livestock and wildlife, the vampire bat distribution and occurrence of rabies outbreaks, as well as environmental modifications, to propose four alternative hypotheses to explain rabies virus emergence and spillover: bat movement, viral invasion, surveillance failure and environmental changes. While future statistical modelling efforts will be required to disentangle these hypotheses, we here show how a detailed historical analysis can be used to generate testable predictions for the conditions leading to pathogen spillover.

Relationships with parents and peers are crucial for children's socialization, but how parent–child and peer relationships mutually affect each other is not well understood. Guided by spillover theory, we zoomed in on the bidirectional interplay between parental rejection and warmth on the one hand and peer victimization on the other, and examined whether children's maladjustment symptoms mediated hypothesized cross-domain spillover effects. Data stem from five waves of the longitudinal KiVa study among 9,770 children (50% boys; mean age = 9.16, standard deviation = 1.29). Results from random intercept cross-lagged panel models showed that higher parental rejection and lower parental warmth predicted increases in peer victimization and vice versa across waves, thus supporting the bidirectional model. Moreover, spillover from parent–child rejection and warmth to peer victimization was partially driven by children's depressive symptoms and bullying perpetration. Vice versa, spillover from peer victimization to parent–child rejection and warmth was partially driven by children's social anxiety, depressive symptoms, conduct problems, and bullying perpetration. Thus, children might get caught in persistent problems in two important social domains, and these two domains influence each other through children's maladjustment. Family and school interventions should be integrated to prevent a downwards spiral.

In order to analyse the effect of hosts’ relationships and the helminthic load on the switching of parasites between native and introduced hosts, we sampled rodents belonging to two suborders from Central Chile. We compared the number of helminthic species shared between murids (introduced) and cricetid (native, same suborder) rodents to those shared between murids and hystricomorphs (native, different suborder), and we assessed the association between parasitic presence, abundance and geographical dispersion in source hosts to the presence and abundance in recipient hosts. Introduced rodent species shared more helminth species with cricetid rodents than with non-cricetids. Presence and abundance in recipient hosts was not associated with the prevalence and mean abundance in source hosts’ population. The mean abundance of parasites in source hosts throughout the territory and wider dispersion was positively associated with the likelihood of being shared with a recipient host. Closer relationships between native and introduced hosts and high parasitic abundance and dispersion could facilitate host switching of helminths between native and introduced rodents. This work provides the first documentation of the importance of parasitic abundance and dispersion on the switching of parasites between native and introduced hosts.

We examine a model of network formation in single-layer and multiplex networks in which individuals have positive incentives for social ties, closed triangles, and spillover edges. In particular, we investigate the influence of shocks to the network in which the cost of social ties changes after an initial equilibrium. We highlight the emergence of structural entrenchment: the retention of structural features, such as closed triangles and spillover edges, which are formed under historically different conditions from those currently driving network evolution. This work has broad implications for understanding path dependence in the structure and dynamics of single-layer and multiplex networks.

We find distiller's dried grains with solubles (DDGS) prices to be positively correlated with both corn and soybean meal prices in the long run. However, neither corn nor soybean meal prices respond to deviations from this long-run relationship. We also identify strong time-varying dynamic conditional correlations between the markets, with the correlation between DDGS and corn strengthened after the expansion of ethanol production. There also appear to exist significant volatility spillovers from both the corn and soybean meal markets to the DDGS market, with the impact from corn shocks much larger compared to soybean meal shocks.