Health Is Associated With Antiparasite Behavior and Fear of Disease-Relevant Animals in Humans

Visual attention is not attuned to non-human animal targets' pathogenicity: an evolutionary mismatch perspective

A considerable amount of research has revealed that there exists an evolutionary mismatch between ancestral environments and conditions following the rise of agriculture regarding the contact between humans and animal reservoirs of infectious diseases. Based on this evolutionary mismatch framework, we examined whether visual attention exhibits adaptive attunement toward animal targets' pathogenicity. Consistent with our predictions, faces bearing heuristic infection cues held attention to a greater extent than did animal vectors of zoonotic infectious diseases. Moreover, the results indicated that attention showed a specialized vigilance toward processing facial cues connoting the presence of infectious diseases, whereas it was allocated comparably between animal disease vectors and disease-irrelevant animals. On the other hand, the pathogen salience manipulation employed to amplify the participants' contextual-level anti-pathogen motives did not moderate the selective allocation of attentional resources. The fact that visual attention seems poorly equipped to detect and encode animals' zoonotic transmission risk supports the idea that our evolved disease avoidance mechanisms might have limited effectiveness in combating global outbreaks originating from zoonotic emerging infectious diseases.

Dissection in biology education compared to alternative methods in terms of their influence on students' emotional experience

Introduction

Dissecting animal organs is a method of biology teaching that offers a direct and authentic view into morphological structures and enables hands-on activity and multisensory experiences. However, the dissection process is often associated with certain (negative) emotions that might hinder successful learning. One such emotion that is particularly common during dissection is disgust. Experiencing disgust can negatively affect emotional experiences. Consequently, alternatives for dissection in biology lessons are being sought.

Methods

In this study, the method of dissection is compared with two common methods of teaching the anatomy of the mammalian eye: watching a video and working with an anatomical model. The focus of the comparison is on the influence on the following emotional qualities of experience: perceived disgust, perceived interest, well-being and boredom. Two hundred and eighteen students (M_age = 14.19, SD_age = 1.02 years, 52% female) from secondary schools in Germany participated in a two-hour lesson on the anatomy of the mammalian eye using one of the three aforementioned teaching methods.

Findings

Our results show that perceived disgust was higher for the dissection group than in the ones that worked with a video or a model. We found that dissecting and watching a video led to a similar level of interest, well-being, and boredom. The anatomical model was perceived as less disgusting but more boring than the dissection. The detailed videos of a dissection seem to offer similar positive emotional experiences when compared to dissecting in class and may be an alternative approach when teachers have concerns about performing a real dissection.

"Bed bugs live in dirty places"-How Using Live Animals in Teaching Contributes to Reducing Stigma, Disgust, Psychological Stigma, and Misinformation in Students

Bed bugs are on the rise and are increasingly perceived as harmful parasites. Because individuals affected by bed bugs often feel disgust and shame and are stigmatized, bed bugs are an important public health and environmental justice concern and therefore a health education issue as well. In this quasi-experimental study, we examine how different constructs, namely, forms of stigma, disgust, psychological distance, and myths about bed bugs (dependent variables), change over time (pre/posttest) in response to two forms of teaching intervention (independent variables) in upper secondary-level high school. The content of the interventions was the same, but in class, we showed live bed bugs to one group of students, assuming this would lead to a more realistic, less imaginative response to bed bugs than in the group presented with only pictures of bed bugs. Together with previous studies, we assumed that live bed bugs would be perceived as less disgusting and with a lower degree of stigmatization. Our results show that stigma, psychological distance, and myths can be reduced through intervention (regardless of live animal or picture). Disgust was more strongly reduced by live animals than by pictures. We present implications for biology education and contemporary health education.

Knowledge, Attitudes, and Practices on Tick-Borne Encephalitis Virus and Tick-Borne Diseases within Professionally Tick-Exposed Persons, Health Care Workers, and General Population in Serbia: A Questionnaire-Based Study

This study assessed the level of knowledge, attitudes, and practices (KAP) regarding tick-borne encephalitis virus (TBEV) and tick-borne diseases (TBDs) among different groups of people in Serbia. Professionally tick-exposed persons (PTEPs), health care workers (HCWs), and the general population (GP) were subjected to an anonymous, voluntary, online questionnaire using Microsoft Forms. A total of 663 questionnaire responses were collected (February–March 2021), while 642 were included in the analysis. The significant difference in knowledge in TBDs existed between GP and PTEPs, and HCWs (p < 0.001). The perception of risk-to-tick exposure and TBDs was generally high (42.4 (95% CI: 33.6–51.2) within GP, 44.9 (95% CI: 35.8–53.9) within PTEPs and 46.2 (95% CI: 38.0–54.5) within HCWs), while fear was low (13.7 (95% CI: 7.9–19.5) within GP, 12.6 (95% CI: 7.3–19.9) within PTEPs, and 13.5 (95% CI: 7.4–19.5) within HCWs). Protective practices differed across groups (F (2639) = 12.920, p < 0.001, η² = 0.039), with both PTEPs (t = 3.621, Cohen d = 0.332, p < 0.001) and HCWs (t = 4.644, Cohen d = 0.468, p < 0.001) adhering to more protective practices than the GP, without differences between PTEPs and HCWs (t = 1.256, Cohen d = 0.137, p = 0.421). Further education about TBDs in Serbia is required and critical points were identified in this study.

The effect of COVID19 pandemic restrictions on an urban rodent population

Shortly after the enactment of restrictions aimed at limiting the spread of COVID-19, various local government and public health authorities around the world reported an increased sighting of rats. Such reports have yet to be empirically validated. Here we combined data from multi-catch rodent stations (providing data on rodent captures), rodent bait stations (providing data on rodent activity) and residents' complaints to explore the effects of a six week lockdown period on rodent populations within the City of Sydney, Australia. The sampling interval encompassed October 2019 to July 2020 with lockdown defined as the interval from April 1st to May 15th, 2020. Rodent captures and activity (visits to bait stations) were stable prior to lockdown. Captures showed a rapid increase and then decline during the lockdown, while rodent visits to bait stations declined throughout this period. There were no changes in the frequency of complaints during lockdown relative to before and after lockdown. There was a non-directional change in the geographical distribution of indices of rodent abundance suggesting that rodents redistributed in response to resource scarcity. We hypothesize that lockdown measures initially resulted in increased rodent captures due to sudden shortage of human-derived food resources. Rodent visits to bait stations might not show this pattern due to the nature of the binary data collected, namely the presence or absence of a visit. Relocation of bait stations driven by pest management goals may also have affected the detection of any directional spatial effect. We conclude that the onset of COVID-19 may have disrupted commensal rodent populations, with possible implications for the future management of these ubiquitous urban indicator species.

Disgust Sensitivity Among Women During the COVID-19 Outbreak

The emotion of disgust is suggested to be an adaptation that evolved to keep us away from sources of infection. Therefore, individuals from populations with greater pathogen stress should have a greater disgust sensitivity. However, current evidence for a positive relationship between disgust sensitivity and the intensity of infectious diseases in the environment is limited. We tested whether disgust and contamination sensitivity changed in response to the COVID-19 pandemic. Disgust was assessed in 984 women in 2017 (before pandemic) and 633 women in 2020 (during pandemic) by a set of photographs depicting sources of infection and Pathogen and Moral of Three-Domain Disgust Scale. Further, contamination sensitivity among participants in two waves was measured by Contamination Obsessions and Washing Compulsions Subscale of Padua Inventory. State anxiety was measured with the Polish adaptation of the State-Trait Anxiety Inventory (STAI) only during the second wave of data collection. Women from the COVID-19 pandemic group assessed the photographs depicting sources of infection as more disgusting, scoring higher on Padua Inventory, but lower on Moral Disgust Domain as compared to women from before the pandemic. In addition, anxiety levels during pandemic positively correlated with scores from Pathogen Disgust Domain, Padua Inventory, and the ratings of the photographs. The participants of the study scored higher in state anxiety than the norms determined for the Polish population. Summarizing, we present evidence for differences in individual levels of disgust sensitivity in relation to pathogen stress, supporting the idea that disgust evolved to serve as protection from pathogens.

The Impact of the Covid-19 Pandemic on Disgust Sensitivity

There have been few tests of whether exposure to naturalistic or experimental disease-threat inductions alter disgust sensitivity, although it has been hypothesized that this should occur as part of disgust's disease avoidance function. In the current study, we asked Macquarie university students to complete measures of disgust sensitivity, perceived vulnerability to disease (PVD), hand hygiene behavior and impulsivity, during Australia's Covid-19 pandemic self-quarantine (lockdown) period, in March/April 2020. These data were then compared to earlier Macquarie university, and other local, and overseas student cohorts, to determine if disgust sensitivity and the other measures, were different in the lockdown sample. The most consistent finding in the lockdown sample was of higher core disgust sensitivity (Cohen's d = 0.4), with some evidence of greater germ aversion on the PVD, and an increase in hand and food-related hygiene, but with little change in impulsivity. The consistency with which greater core disgust sensitivity was observed, suggests exposure to a highly naturalistic disease threat is a plausible cause. Greater disgust sensitivity may have several functional benefits (e.g., hand and food-related hygiene) and may arise implicitly from the threat posed by the Covid-19 pandemic.

Pharyngeal Detection of Staphylococcus aureus as a Possible Factor Related to Disgust Sensitivity in Humans

Disgust triggers behavioral avoidance of pathogen-carrying and fitness-reducing agents. However, because of the cost involved, disgust sensitivity should be flexible, varying as a function of an individual’s immunity. Asymptomatic colonization with Staphylococcus aureus often results from weakened immunity and is a potential source of subsequent infections. In this study, we tested if pharyngeal colonization with S. aureus, evaluated based on a single swab collection, is related to an individual’s disgust sensitivity, measured with the Three Domain Disgust Scale. Levels of immunomodulating hormones (cortisol and testosterone), general health, and body adiposity were controlled. Women (N = 95), compared to men (N = 137), displayed higher sexual disgust sensitivity, but the difference between individuals with S. aureus and without S. aureus was significant only in men, providing support for prophylactic hypothesis, explaining inter-individual differences in disgust sensitivity. Men (but not women) burdened with asymptomatic S. aureus presence in pharynx exhibit higher pathogen disgust (p = 0.04) compared to individuals in which S. aureus was not detected. The positive relationship between the presence of the pathogen and sexual disgust was close to the statistical significance level (p = 0.06), and S. aureus colonization was not related with moral disgust domain.

Implications of the behavioural immune system for social behaviour and human health in the modern world

The 'behavioural immune system' is composed of mechanisms that evolved as a means of facilitating behaviours that minimized infection risk and enhanced fitness. Recent empirical research on human populations suggests that these mechanisms have unique consequences for many aspects of human sociality--including sexual attitudes, gregariousness, xenophobia, conformity to majority opinion and conservative sociopolitical attitudes. Throughout much of human evolutionary history, these consequences may have had beneficial health implications; but health implications in modern human societies remain unclear. This article summarizes pertinent ways in which modern human societies are similar to and different from the ecologies within which the behavioural immune system evolved. By attending to these similarities and differences, we identify a set of plausible implications-both positive and negative-that the behavioural immune system may have on health outcomes in contemporary human contexts. We discuss both individual-level infection risk and population-level epidemiological outcomes. We also discuss a variety of additional implications, including compliance with public health policies, the adoption of novel therapeutic interventions and actual immunological functioning. Research on the behavioural immune system, and its implications in contemporary human societies, can provide unique insights into relationships between fitness, sociality and health.

Is a woman's preference for chest hair in men influenced by parasite threat?

Humans (Homo sapiens) are unique primates due to a lack of a thermally insulating fur covering, typical of all other primates. Our primary goal was to examine the "ectoparasite avoidance mediated by mate choice hypothesis" suggesting that women prefer men lacking chest hair in order to avoid ectoparasite loads. We predicted that women living in areas with high prevalence of pathogens (n = 161) would be less likely to show a preference for a male with chest hair in comparison with women living in areas with low pathogen prevalence (n = 183). We found that overall preference for man chest hair was low, but there were no significant associations between perceived vulnerability to diseases or disgust sensitivity and preference of men who have had experimentally removed chest hair. Women who lived in an environment with a high parasite prevalence rate (Turkey) showed a similar preference for man chest hair as did women from an environment with low parasite prevalence (Slovakia). The participants biological fathers' chest hair had no significant effect on their preference for men with chest hair. Women living in a high-parasite-prevalence environment reported a higher disgust score in the sexual domain and more recent experiences with illnesses, suggesting that parasites influence sensitivity to sexual disgust. These results provide no support for the ectoparasite avoidance hypothesis mediated by mate choice and suggest that shaved men bodies are preferred more by women.

Bugging forecast: unknown, disliked, occasionally intimate. Bed bugs in Germany meet unprepared people

Bed bugs appear to be feared more than vector insects and other household pests. The reasons for this exaggerated fear are not fully understood. One hypothesis is that the folk knowledge on recognising and controlling bed bugs decreased as bed bugs became rarer in the 1960s and led to irrational perceptions. Here, we examine people’s ability to recognise a bed bug and their response what to do in case of an infestation. We found that 13% of a sample of 391 people in four large German cities recognised a bed bug; 15% of all respondents would call a pest controller in case of bed bug infestation. This results in the pessimistic estimate that 97% of all early-stage infestations could go untreated. We discuss additional scenarios. The effectiveness of efforts to educate people about the presence of bed bugs has never been tested, but our sample is useful to guide future studies. We found three sources of information were associated with increased recognition rates of bed bugs: a) previous contacts with bed bugs (60% recognition), b) knowledge from friends or relatives (25%) and school or education courses (15%). By contrast, people who heard of bed bugs from television, print media or the Internet showed reduced recognition rates. We propose that the former factors be tested for educational interventions. In Germany, the bed bug is an estranged creature to many people, a fact that seems to hinder rational approaches to their control.

Self-Protection Versus Disease Avoidance

Predators and pathogens are powerful natural selection tools that influence the evolution of two domain-specific management systems: self-protection and disease avoidance. Both systems are activated by specific ecological conditions and protect humans against physical harm or disease transmission. The perception of predators is associated with fear, and the perception of disease-relevant animals is associated with disgust. Fear of predators negatively correlated with the perceived physical condition of participants, suggesting that the self-protection system is activated particularly in people who are more vulnerable to predation threat. People vulnerable to infectious diseases rated predators as more dangerous, suggesting that the disease-avoidance system activates behavior-reducing contact with harmful animals. Females had a higher score in terms of fear, disgust, and perceived danger in particular when considering animals that pose physical harm and/or a disease threat. Our results support the adaptation view, suggesting that the self-protection and disease-avoidance systems are domain specific, and that both have been shaped by natural selection in order to protect humans against harmful animals or events.

The Effect of Owning Animals on Perceived Vulnerability to, and Avoidance of, Parasitic Diseases in Humans

The evolutionary history of humans has always been influenced by pathogens because of their ability to cause both morbidity and mortality. Natural selection should favor behavioral strategies that minimize disease transmission and consequently increase human survival. Collectively such strategies are referred to as the behavioral immune system, which is thought to be more often activated in individuals with an impaired immune system who are most vulnerable to pathogens and infectious diseases. We investigated the associations between an individual’s perceived vulnerability to disease, whether they own any animals, and whether they carry out behavioral tactics to avoid parasite transmission. A sample of 285 Slovakian students participated in a questionnaire study. As predicted, antipathogen behavior was activated in individuals with a high perceived vulnerability to disease. Females showed higher antiparasitic scores than males especially when behaviors were most likely to transmit disease. Individuals who owned animals perceived themselves as less vulnerable to disease as well as less vulnerable to the perceptions of those who did not own any animals. Moreover, among animal owners scores for parasite-avoiding behaviors relevant to being in close contact with an animal (such as removing animal feces and worming animals) were higher than for parasite-transmitting behaviors relevant to being in close contact with an animal (such as allowing animals to lick). We discuss the results, further taking into account both the model of natural selection and the coevolutionary arms race model.