Impact of parasitic infection on mental health and illness in humans in Africa: a systematic review.

A growing body of research implicates inflammation as a potential pathway in the aetiology and pathophysiology of some mental illnesses. A systematic review was conducted to determine the association between parasitic infection and mental illnesses in humans in Africa and reviewed the state of the evidence available. The search focused on publications from Africa documenting the relationship between parasites from two parasite groups, helminths and protozoans, and four classifications of mental illness: mood affective disorders, neurotic and stress-related disorders, schizotypal disorders and unspecified mental illnesses. In the 26 reviewed papers, the prevalence of mental illness was significantly higher in people with parasitic infection compared to those without infection, i.e., 58.2% vs 41.8% (P < 0.001). An overall odds ratio found that the association of having a mental illness when testing positive for a parasitic infection was four times that of people without infection. Whilst the study showed significant associations between parasite infection and mental illness, it also highlights gaps in the present literature on the pathophysiology of mental illness in people exposed to parasite infection. This study highlighted the importance of an integrated intervention for parasitic infection and mental illness.

A preliminary report on the awareness and knowledge of seafood-borne parasitic diseases among medical doctors in Australia.

Despite the increasing popularity of seafood in Australia and various reports of infection with transmissible parasites in Australian edible aquatic animals such as fish, the number of reported cases of human infections in the country is low. This raised the question that Australian medical doctors may not be fully aware of the presence of these parasites in Australia, which in turn can lead to misdiagnosis of infections. This also may lead to an underestimation of the risk seafood-borne parasites may pose to public health. This preliminary study was conducted to determine the awareness and level of knowledge among Australian medical practitioners in New South Wales, the most populated and multicultural state in Australia, about seafood-borne parasitic diseases. Medical doctors, both general practitioners and gastroenterologists, were surveyed through an anonymous questionnaire (n = 376). Although the response rate was low at 11%, participants represented a diverse group in terms of gender, age, nationality and expertise. Despite several publications on occurrence of zoonotic parasites in Australian fish and other edible aquatic animals, and also in humans in the country, all respondents said no seafood-borne parasite had been reported as being seen within Australian or overseas practice. Although, due to low response rate, we are unable to confidently comment on the level of awareness, the findings of this study clearly suggest that further research is needed to investigate the extent of unawareness among Australian medical doctors about these highly important parasites and understanding the underlying issues in medical education that lead to the unawareness.

Developing a model of health behavior change to reduce parasitic disease in Vietnam.

Worldwide more deaths occur due to conditions that can be ameliorated by behavior change. Changing health behaviors using models popularized in non-western countries has not proven particularly successful. The purpose of this study was to test variables elicited during qualitative interviews and cultural conversations to develop a model of health behavior change from the ground up in Vietnam. Village leaders and women representatives from the Women's Committee were trained as health advocates to facilitate changes in health practices that led to parasitic and infectious diseases. The health advocates visited 156 families to assess household conditions and assist women head-of-households in applying new behaviors to water treatment, personal hygiene, proper latrining and proximity of animals to humans. Predictors that were tested were self-efficacy, social desirability, internal and external control, and outcome expectations. The correlational and regression design resulted in self-efficacy alone predicting both home hygiene and family health with a large effect size. Social desirability appears to play a different role than in western culture studies. Outcome expectations and control were not predictive. A cultural analysis of the results is included.

Children with a mother with delusional infestation--implications for child protection and management.

Delusional infestation (DI) is a reportedly uncommon psychocutaneous condition in which an individual holds a fixed, false belief of pathogenic infestation of the skin or body contrary to medical evidence. There are reports of such a delusion being shared with family members or close friends (folie a deux/famillie), but the implications of DI induced in children have not been discussed. We describe the case of a mother with DI whose children subsequently shared her belief. Implications for child protection and management are explored.

Delusions of parasitosis; suggested dialogue between dermatologist and patient.

Delusions of parasitosis (DoP) is a psychocutaneous condition characterized by a fixed false belief that one is infested by skin parasites. Patients afflicted with DoP generally experience sensations of biting, stinging or crawling in the absence of any objective evidence of infestation. The most definitive treatment for DoP is antipsychotic agents. Though the diagnosis and treatment options are rather straightforward, the difficulty lies in the art of building a therapeutic rapport with the patient in order to encourage acceptance of antipsychotic treatment. This article is a practical guide that suggests verbatim how dermatologists might talk to a delusional patient in order to establish a strong therapeutic rapport. Strategies on how to optimize the initial encounter, build rapport and prescribe antipsychotic medications that are likely to be accepted by the patient are discussed.

European green lizard (Lacerta viridis) personalities: Linking behavioural types to ecologically relevant traits at different ontogenetic stages.

Consistent individual differences within (animal personality) and across (behavioural syndrome) behaviours became well recognized during the past decade. Nevertheless, our knowledge about the evolutionary and developmental mechanisms behind the phenomena is still incomplete. Here, we explored if risk-taking and exploration were consistent and linked to different ecologically relevant traits in wild-caught adult male European green lizards (Lacerta viridis) and in their 2-3 weeks old laboratory-reared offspring. Both adults and juveniles displayed animal personality, consistency being higher in juveniles. We found correlation between risk-taking and exploration (suggestive of a behavioural syndrome) only in adults. Juveniles were more explorative than adults. Large or ectoparasite-free adult males were more explorative than small or parasitized males. Juvenile females tended to be more risk-taking than males. Behaviour of fathers and their offspring did not correlate. We conclude that European green lizards show high behavioural consistency and age is an important determinant of its strength and links to traits likely affecting fitness.

Health-related quality of life among school children with parasitic infections: findings from a national cross-sectional survey in Côte d'Ivoire.

BACKGROUND: Parasitic infections are still of considerable public health relevance, notably among children in low- and middle-income countries. Measures to assess the magnitude of ill-health in infected individuals, however, are debated and patient-based proxies through generic health-related quality of life (HrQoL) instruments are among the proposed strategies. Disability estimates based on HrQoL are still scarce and conflicting, and hence, there is a need to strengthen the current evidence-base. METHODOLOGY: Between November 2011 and February 2012, a national school-based cross-sectional survey was conducted in Côte d'Ivoire. Children underwent parasitological and clinical examination to assess infection status with Plasmodium and helminth species and clinical parameters, and responded to a questionnaire interview incorporating sociodemographic characteristics, self-reported morbidity, and HrQoL. Validity analysis of the HrQoL instrument was performed, assessing floor and ceiling effects, internal consistency, and correlation with morbidity scores. Multivariate regression models were applied to identify significant associations between HrQoL and children's parasitic infection and clinical status. PRINCIPAL FINDINGS: Parasitological examination of 4,848 children aged 5-16 years revealed Plasmodium spp., hookworm, Schistosoma haematobium, Schistosoma mansoni, Ascaris lumbricoides, and Trichuris trichiura prevalences of 75.0%, 17.2%, 5.7%, 3.7%, 1.8%, and 1.3%, respectively. Anemic children showed a significant 1-point reduction in self-rated HrQoL on a scale from 0 to 100, whereas no significant negative association between HrQoL and parasite infection was observed. The 12-item HrQoL questionnaire proofed useful, as floor and ceiling effects were negligible, internally consistent (Cronbach's alpha = 0.71), and valid, as revealed by significant negative correlations and associations with children's self-reported and clinically assessed morbidity. CONCLUSIONS/SIGNIFICANCE: Our results suggest that HrQoL tools are not sufficiently sensitive to assess subtle morbidities due to parasitic infection in Ivorian school-aged children. However, more advanced morbid sequelae (e.g., anemia), were measurable by the instrument's health construct. Further investigations on health impacts of parasitic infection among school-aged children and refinement of generic HrQoL questionnaires are warranted.

Parasites enhance self-grooming behaviour and information retention in humans.

Self-grooming is a common behavioural strategy used by various animals to reduce parasite loads. We experimentally tested the adaptive significance of self-grooming model in a sample of Slovak participants. Propensity to self-grooming was activated by visual presence of parasites with verbal information about health risks caused by parasites suggesting that the programmed grooming model works in humans. People who think of themselves as more vulnerable to disease transmission reported higher frequency of self-grooming suggesting that there is a link between the immune system and parasite avoidance behaviour. Considering that the emotion of disgust plays a role in activation of parasite avoidance behaviour, we suggested that knowledge of disgusting stimuli (parasites) would be better retained than knowledge of non-disgusting (hormones), and, thus, non-life-threatening stimuli. As expected, knowledge on parasites tested immediately after the experiment was significantly better than knowledge on hormones suggesting that survival-relevant information is better retained than survival-irrelevant data. However, scores on memory tests did not seem to be influenced by the individual's immune system. Overall, this study showed that self-grooming in humans is functional when disease threat is salient. Human memory systems are tuned to information relevant to survival providing further evidence that human cognition is shaped by natural selection.

[Health education for major parasitic diseases in rural community of China: current status and future development].

Owing to human parasitic diseases being related to behavior, the health education as an important measure to prevent parasite infections through human behavior intervention, has played an important role in the process of parasitic disease prevention and control in rural area of China. This paper comments on the development history of the health education for parasitic disease prevention and control, current intervention modes and the effect of the health education for parasitic diseases in rural area. This paper also summarizes the role and impact of different modes of the health education for parasitic disease prevention and control and gives some suggestions to future development of the health education in rural area under current prevalent situation of parasitic diseases.

Trigeminal trophic syndrome: report of 3 cases affecting the scalp.

Trigeminal trophic syndrome (TTS) is a rare condition that results from a prior injury to the sensory distribution of the trigeminal nerve. Patients typically respond to the altered sensation with self-mutilation, most often of the nasal ala. We describe 3 patients with TTS who presented with self-induced ulcerations primarily involving the scalp. Two patients developed delusions of parasitosis (DOP) based on the resulting symptoms of TTS, which is a unique association. Trigeminal trophic syndrome may occur at extranasal sites and in any branch of the trigeminal nerve. The condition should be considered when ulcers are encountered in this nerve distribution. Symptoms such as formication may mimic DOP. Trigeminal trophic syndrome may be differentiated from DOP by the restriction of symptoms and ulcerations to the distribution of the trigeminal nerve.

Entomophobia, acarophobia, parasitic dermatophobia or delusional parasitosis.

Entomophobia or acarophobia, parasitic dermatophobia (PD) or delusional parasitosis (DP) is a disorder in which affected individuals has the mistaken but unshakable belief (delusion) that they are infected by insects, spiders, scorpion, ticks, mites, parasitic worms, bacteria, or other living organisms. As with all delusions, this belief cannot be corrected by reasoning, persuasion, or logical argument. To avoid them, they may always be cleaning rooms, floors, doors, windows and scratching. Many affected individuals are quite functional; for the minority, delusions of parasitic infection may interfere with usual activities. However, most insects are not harmful to humans and pose no threat, those who suffer with this phobia experience extreme anxiety at the mere thought or sight of an insect. Most patients consult dermatologists, veterinarians, pest control specialists, or entomologists. The DP cases are increasing worldwide; it remains an extremely unrepeatable disorder.

New findings in delusions of parasitosis.

Two new cases are presented with delusions of parasitosis. Both were women, one middle-aged and one elderly, and exhibited classic symptoms of parasites and "strings" in the skin indicative of Morgellons disease. Each had an additional psychiatric disorder: drug addiction to cocaine and senile dementia. They also illustrate the difficulty encountered by the dermatologist in providing adequate therapy because of resistance to psychiatric referral as well as to standard accepted medication. Newer psychotropics, such as risperdal and lexapro, show promise in helping these patients and add to the therapeutic armamentarium of pimozide.

The parasite-stress theory may be a general theory of culture and sociality.

In the target article, we presented the hypothesis that parasite-stress variation was a causal factor in the variation of in-group assortative sociality, cross-nationally and across the United States, which we indexed with variables that measured different aspects of the strength of family ties and religiosity. We presented evidence supportive of our hypothesis in the form of analyses that controlled for variation in freedom, wealth resources, and wealth inequality across nations and the states of the USA. Here, we respond to criticisms from commentators and attempt to clarify and expand the parasite-stress theory of sociality used to fuel our research presented in the target article.

Parasite-stress, cultures of honor, and the emergence of gender bias in purity norms.

Of the many far-reaching implications of Fincher & Thornhill's (F&T's) theory, we focus on the consequences of parasite stress for mating strategies, marriage, and the differing roles and restrictions for men and women. In particular, we explain how examination of cultures of honor can provide a theoretical bridge between effects of parasite stress and disproportionate emphasis on female purity.

Climato-economic livability predicts societal collectivism and political autocracy better than parasitic stress does.

A 121-nation study of societal collectivism and a 174-nation study of political autocracy show that parasitic stress does not account for any variation in these components of culture once the interactive impacts of climatic demands and income resources have been accounted for. Climato-economic livability is a viable rival explanation for the reported effects of parasitic stress on culture.

Intra-regional assortative sociality may be better explained by social network dynamics rather than pathogen risk avoidance.

Fincher & Thornhill's (F&T's) model is not entirely supported by common patterns of affect behaviors among people who live under varying climatic conditions and among people who endorse varying levels of (Western) religiosity and conservative political ideals. The authors' model is also unable to account for intra-regional heterogeneity in assortative sociality, which, we argue, can be better explained by a framework that emphasizes the differential expression of fundamental social cues for maintaining distinct social network structures.