The efficacy of sampling strategies for estimating scabies prevalence

BackgroundEstimating community level scabies prevalence is crucial for targeting interventions to areas of greatest need. The World Health Organisation recommends sampling at the unit of households or schools, but there is presently no standardised approach to scabies prevalence assessment. Consequently, a wide range of sampling sizes and methods have been used. As both prevalence and drivers of transmission vary across populations, there is a need to understand how sampling strategies for estimating scabies prevalence interact with local epidemiology to affect the accuracy of prevalence estimates.MethodsWe used a simulation-based approach to compare the efficacy of different scabies sampling strategies. First, we generated synthetic populations broadly representative of remote Australian Indigenous communities and assigned a scabies status to individuals to achieve a specified prevalence using different assumptions about scabies epidemiology. Second, we calculated an observed prevalence for different sampling methods and sizes.ResultsThe distribution of prevalence in subpopulation groups can vary substantially when the underlying scabies assignment method changes. Across all of the scabies assignment methods combined, the simple random sampling method produces the narrowest 95% confidence interval for all sample sizes. The household sampling method introduces higher variance compared to simple random sampling when the assignment of scabies includes a household-specific component. The school sampling method overestimates community prevalence when the assignment of scabies includes an age-specific component.DiscussionOur results indicate that there are interactions between transmission assumptions and surveillance strategies, emphasizing the need for understanding scabies transmission dynamics. We suggest using the simple random sampling method for estimating scabies prevalence. Our approach can be adapted to various populations and diseases.     

A national survey of musculoskeletal impairment in Rwanda: prevalence, causes and service implications

Background

Accurate information on the prevalence and causes of musculoskeletal impairment (MSI) is lacking in low income countries. We present a new survey methodology that is based on sound epidemiological principles and is linked to the World Health Organisation''s International Classification of Functioning.

Methods

Clusters were selected with probability proportionate to size. Households were selected within clusters through compact segment sampling. 105 clusters of 80 people (all ages) were included. All participants were screened for MSI by a physiotherapist and medical assistant. Possible cases plus a random sample of 10% of non-MSI cases were examined further to ascertain diagnosis, aetiology, quality of life, and treatment needs.

Findings

6757 of 8368 enumerated individuals (80.8%) were screened. There were 352 cases, giving an overall prevalence for MSI of 5.2%. (95% CI 4.5–5.9) The prevalence of MSI increased with age and was similar in men and women. Extrapolating these estimates, there are approximately 488,000 MSI diagnoses in Rwanda. Only 8.2% of MSI cases were severe, while the majority were moderate (43.7%) or mild (46.3%). Diagnostic categories comprised 11.5% congenital, 31.3% trauma, 3.8% infection, 9.0% neurological, and 44.4% non-traumatic non infective acquired. The most common individual diagnoses were joint disease (13.3%), angular limb deformity (9.7%) and fracture mal- and non-union (7.2%). 96% of all cases required further treatment.

Interpretation

This survey demonstrates a large burden of MSI in Rwanda, which is mostly untreated. The survey methodology will be useful in other low income countries, to assist with planning services and monitoring trends.     

Nonsuicidal self-harm in youth: a population-based survey

Background

Nonsuicidal self-harm includes cutting, scratching, burning and minor overdosing. There have been few studies that have examined the rate of self-harm and mental-health correlates among community-based youth. We performed a population-based study to determine the prevalence of nonsuicidal self-harm, its mental-health correlates and help-seeking behaviour.

Methods

We used data from the Victoria Healthy Youth Survey, a population-based longitudinal survey of youth aged 14–21 in Victoria, British Columbia. The survey included questions about the history, method, frequency, age of onset and help-seeking for nonsuicidal self-harm. Youth were interviewed between February and June 2005. Univariable group differences were analyzed using students t test for continuous data and χ² for binary or categorical data. Multivariate analyses were conducted by use of multivariate analysis of variance and logistic regression.

Results

Ninety-six of 568 (16.9%) youth indicated that they had ever harmed themselves. Self-injuries such as cutting, scratching and self-hitting were the most common forms of nonsuicidal self-harm (83.2%). The mean age of onset was 15.2 years. Of those who reported nonsuicidal self-harm, 56% had sought help for this behaviour. Participants who reported 5 or more symptoms (out of 6) in a given symptom category were more likely than those who reported less than 5 symptoms to report nonsuicidal self-harm for the following categories: depressive mood (odds ratio [OR] 2.18, confidence interval [CI] 1.28–3.7) and problems with regulation of attention, impulsivity and activity (OR 2.24, CI 1.33–3.76).

Interpretation

We found a high lifetime prevalence of nonsuicidal self-harm. Many mental-health symptoms were associated with this behaviour, particularly those with depressive mood and attention-related problems. Just over half of youth reported seeking help for nonsuicidal self-harm. Clinicians who encounter youth should be vigilant to assess for this behaviour in youth who present with mental health issues.Nonsuicidal self-harm includes behaviours such as self-cutting, scratching and burning, done without the conscious intent to take one''s life. Onset typically occurs between 14 and 24 years of age.^1,2 The most common reasons for this type of harm are regulation of affect (e.g., to reduce tension or relieve dysphoric feelings), but reasons may also include self-punishment, interpersonal reasons, sensation seeking and anti-dissociation mechanisms.³ Factors associated with nonsuicidal self-harm include being female, awareness of self harm in peers, family members who self harm, drug misuse, depression, anxiety, impulsivity, disruptive disorders and low self-esteem.^4,5 Suicide ideation and attempts are more likely to be reported among those with repeated nonsuicidal self-harm.⁶A definition of “deliberate self-harm,” which does not distinguish between suicidal and nonsuicidal intent, has been proposed by the Child and Adolescent Self-Harm in Europe research group and has been used in several school-based surveys of adolescents.^4,7 The prevalence self-harm has been studied in school-based surveys of adolescents and young adults.^4–6,8 The results of these surveys are of limited generalizability because the samples were restricted to schools in large urban centres. Thus, we performed a population-based survey of youth in western Canada to investigate nonsuicidal self-harm. Our objectives were to determine the rate of nonsuicidal self-harm among Canadian youth; to determine the mental-health factors associated with nonsuicidal self-harm; and to examine the help-seeking patterns for this behaviour.     

Sex differences in the prevalence of congenital anomalies: a population-based study

BACKGROUND: Limited data is available concerning the sex distribution of various congenital anomaly subtypes. This study investigated sex differences in the prevalence of congenital anomalies, overall and by subtype, using high quality population‐based data from the North of England. METHODS: Information on congenital anomalies occurring among singleton pregnancies during 1985–2003 were extracted from the Northern Congenital Abnormality Survey (NorCAS). Anomalies were categorized by groups, subtypes, and syndromes according to the European Surveillance of Congenital Anomalies guidelines. Relative risks (RRs) comparing the prevalences in males to that in females were calculated for a range of congenital anomaly subtypes. RESULTS: A total of 12,795 eligible cases of congenital anomaly were identified during the study period, including 7019 (54.9%) males and 5776 (45.1%) females. Overall, male fetuses were significantly more prevalent in pregnancies affected by a congenital anomaly than female fetuses (RR, male vs. female = 1.15; 95% confidence interval [CI], 1.11–1.19), but there was significant heterogeneity between subtypes (p < 0.001). Forty‐four of 110 (40%) unique subtypes were at least 40% more prevalent in males than females, with affected subtypes occurring across all major anomaly groups. Thirteen of 110 (12%) unique subtypes were at least 40% more prevalent in females than males, but the female‐biased RR of a neural tube defect was less pronounced than previously reported (RR = 0.84; 95% CI, 0.73–0.95). CONCLUSION:This study adds to the growing evidence of sex‐specific differences in the prevalence of a wide range of congenital anomaly subtypes. Birth Defects Research (Part A), 2011. © 2011 Wiley‐Liss, Inc.     

The scourge of scabies

Scabies ('Itch Mite') is truly a Great Neglected Disease that inflicts misery on millions. Molecular approaches, while still in their infancy, are providing a better understanding of the parasite and will have important implications for control and prevention. It has long been thought that dogs may act as a reservoir for human infections. However, genetic studies cast doubt over this supposition.     

Association between prehypertension and psychological distress among adults in Saudi Arabia: A population-based survey

BackgroundPrehypertension is a precursor to hypertension status. Psychological distress has been identified earlier among hypertensives; however, there is little evidence for the presumptive relationship between prehypertension and psychological distress.ObjectiveThe study aimed to assess the psychological wellbeing of the Al-Kharj, Saudi Arabia population, using the General Health Questionnaire (GHQ-12) and correlating it with prehypertensive patients in the same population.MethodsA cross-sectional analysis of the population of Al-Kharj, Saudi Arabia, was carried out between January and June of 2016. With an 85 percent response rate, a total of 1016 participants participated in the study. A multiple linear regression analysis was performed to assess the relationship between prehypertension and psychological distress.ResultsThe findings of the adjusted analysis demonstrated that, on average prehypertensive patients were more distressed psychologically than non-hypertensive patients (unstandardized Beta regression coefficient = 3.600; P-value 0.025). Similarly, on average women were found to be more psychologically distressed than men (unstandardized Beta = 1.511, P-value 0.002). Civil workers and unemployed individuals were more psychologically distressed than employed individuals (unstandardized Beta = 1.326, P-value 0.041) while adjusting for the sociodemographic and other variables such as BMI, diabetes status, cholesterol, and smoking status.ConclusionThe current study shows that as compared to normotensive patients, self-rated mental wellbeing and psychological wellbeing are all considerably poorer among prehypertensive patients. To prevent individuals from having negative psychological outcomes and their long-term complications, the Government of Saudi Arabia needs to concentrate on prehypertensive, female, and unemployed individuals. Well-designed longitudinal studies, primarily in Saudi Arabia, are needed in the future to research the cause and impact of poor mental health and prehypertension.     

A survey of the prevalence of selected bacteria in wild birds

We determined the prevalence of six genera of bacteria from a sample of 387 cloacal swabs from 364 passerines and woodpeckers. The prevalence of bacteria were as follows: Escherichia coli (1%), Pseudomonas spp. (22%), Salmonella spp. (0%), Staphylococcus spp. (15%), Streptococcus spp. (18%), and Yersinia spp. (1%). The prevalence of Streptococcus spp. was higher in omnivorous species than in granivorous species (20% versus 8%). Individuals captured at feeders had a lower prevalence of both Streptococcus spp. (15% versus 33%) and Escherichia coli (0.5% versus 4%) than birds that did not have access to feeders. These differences are probably not due to the feeder per se, but instead to other site related differences. The prevalence of bacteria did not differ between male and female black-capped chickadees, Parus atricapillus. For 279 color marked black-capped chickadees, we calculated the cumulative mortality rate during 12 wk following swabbing. Although the cumulative mortality rates of infected birds were consistently higher than the rates of non-infected birds, none of these differences were significant. Infections may cause slight reductions in survival rates, but we were not able to confirm this with our data.     

High prevalence of oncogenic HPV-16 in cervical smears of asymptomatic women of eastern Uttar Pradesh,India: A population-based study

In developing countries like India, occurrence of Human papillomavirus (HPV) in cervical cancer as well as in the asymptomatic population was observed to be very high. Studies on HPV prevalence have been conducted in different parts of the country but no data were available from the eastern region of Uttar Pradesh (UP). The present study aimed to determine the status of HPV prevalence and its association with different socio-demographic factors in this population. Prevalence of HPV was investigated in a total of 2424 cervical scrape samples of asymptomatic women. Primer sets from L1 consensus region of viral genome were used to detect the presence of HPV, and the positive samples were genotyped by sequencing. Univariate binary logistic regression analysis was used to evaluate association of socio-demographic factors with HPV. 9.9% of the clinically asymptomatic women were found to be infected with HPV comprising 26 different genotypes. Among HPV-positive women, 80.8% showed single infection, while 15.4% harboured multiple infections. HPV-16 (63.7%) was the most prevalent, followed by HPV-31 (6.7%), HPV-6 (5.4%), HPV-81 (4.6%) and HPV-33 (4.2%). Significant association of HPV with non-vegetarian diet (P < 0.05) and rural residential areas (P < 0.01) were observed. High prevalence of HPV-16 in asymptomatic women of this population, a frequency comparable to invasive cervical cancers, highlights an urgent need for a therapeutic HPV vaccine covering HPV-16 and other high-risk types to provide protection against the disease.     

The prevalence and distribution of sheep scab in Wales: a farmer questionnaire survey

Outbreaks of ovine psoroptic mange in the U.K. have increased 100‐fold since its deregulation in 1992, with the highest prevalence in Wales, a region of high sheep density. A cross‐sectional, retrospective, questionnaire‐based survey of 7500 members of the association of Welsh lamb and beef farmers [Welsh Lamb and Beef Producers Ltd (WLBP)] was used to investigate the prevalence and distribution of sheep scab in this region in 2015. The survey was completed by 14.0% (n = 972) of potential respondents. Scab outbreaks were reported on 15.8% (n = 154) of farms in 2015. However, 29.0% (n = 282) of farms reported at least one scab outbreak and 2.4% (n = 23) of farms had experienced between six and 10 outbreaks in the previous 10 years. Most outbreaks occurred during September–January (83.0%, n = 150), and were clustered around Brecon (mid‐Wales) and Bangor (North Wales). Farmers who used common grazing were significantly more likely to report scab outbreaks in the previous 10 years than farmers who did not. No quarantine procedures for sheep bought in were used by 29.0% (n = 262) of farmers. Future research should be directed towards the development of localized management programmes, with a particular focus on areas of common grazing.     

A study of Aphyosemion schmitti (Romand, 1979) and a survey of the Aphyosemion of Liberia (Pisces, Cyprinodontidae)

Aphyosemion schmitti can be separated from neighbouring species on the basis of colour pattern, crossing experiments, cytogenetics, genetics and zoogeographical distribution. Three groups of Aphyosemion can be distinguished, based on morphological and meristic characters, colour patterns and geographical distribution; i.e. the liberiense group, the guineense group and the occidentalis group. A differentiation of the Liberian Aphyosemion is proposed, and its possible phylogenetic relationships are discussed.     

Inflammatory adipokines, high molecular weight adiponectin, and insulin resistance: a population-based survey in prepubertal schoolchildren

Background

The aim of this study was to investigate sex differences and associations of high molecular weight (HMW) adiponectin, leptin and proinflammatory adipokines, individually or in combinations, with adiposity and insulin resistance (IR) measures in prepubertal childhood.

Methodology

We studied 305 prepubertal children (boys/girls: 144/161; Tanner stage 1; age: 5-13 yr), included in a cohort of 44,231 adolescents who participated in an extensive Italian school-based survey. According to Cole''s criteria, 105 individuals were lean (L; boys/girls: 59/46), 60 overweight (OW; boys/girls: 32/28) and 140 obese (OB; boys/girls: 70/70). Measurements comprised total and HMW adiponectin, leptin, as well as a panel of proinflammatory adipokines/chemokines associated with diabetes risk.

Principal Findings

Leptin-, and the leptin-to-HMW adiponectin ratio (L/HMW)-, increased progressively (p<0.0001) from L to OW to OB boys and girls. When compared with L peers, OW and OB girls exhibited lower (p<0.001) HMW adiponectin levels, while in boys the HMW multimers did not differ significantly across the BMI-stratified groups. OB girls displayed higher (p<0.05) IL-8, IL-18, monocyte chemoattractant protein-1 (MCP-1) and soluble intercellular adhesion molecule-1 levels (sICAM-1) than L girls, whereas increased macrophage migration inhibitory factor (MIF) concentrations in OB vs OW boys were seen. HMW adiponectin (negatively), leptin or inflammatory markers (positively) correlated with adiposity and IR measures. In multivariate models, leptin represented a strong and independent determinant of HOMA-IR (R² 0.378; p<0.01). Adjustment for age, BMI_z-score, lipids and inflammatory mediators abolished the association between leptin and HOMA-IR in boys, while in girls leptin remained still a significant predictor of IR (R² 0.513; p<0.01). Finally, in both sexes, the joint effect of the L/HMW did not improve the prediction of basal IR as compared with leptin levels alone, which were mainly explained by the BMI_z-score.

Conclusions

In prepubertal children, leptin emerges as a sex-independent discrimination marker of adiposity degree and as a useful, sex-associated predictor of the systemic insulin resistance.     

A survey on the prevalence of gastrointestinal parasites of dogs in the area of Thessaloniki, Greece

Faecal specimens randomly taken from 232 healthy dogs living in the area of Thessaloniki were screened for internal parasites. In 39.2% of the examined dogs excretion of Sarcocystis bovicanis (1.3%), Isospora ohioensis/burrowsi (3.9%), Giardia lamblia (0.8%), Hammondia heydorni (0.4%), Dicrocoelium dendriticum (0.8%) Diplopylidium nolleri (0.4%), Joyeuxiella pasqualei (0.8%), taeniids (0.4%), Toxocara canis (22.4%), Toxascaris leonina (1.3%), Uncinaria stenocephala (3.0%), Trichuris vulpis (2.6%), Spirocerca lupi (0.4%), or Linguatula serrata (0.4%) was detected. The overall rate of infection did not show any significant difference concerning sex or age. T. canis, however, was significantly more often found in the youngest age group (1-3 months).     

Sex differences in the prevalence of human birth defects: a population-based study.

BACKGROUND: Sex differences in the prevalence of several human birth defects have often been reported in the literature, but the extent of sex differences for most birth defects is unknown. To determine the full extent of sex differences in birth defects in a population, we examined population-based data from the Metropolitan Atlanta Congenital Defects Program (MACDP). METHODS: MACDP records were analyzed for 1968 through 1995. We determined the sex-specific prevalence of all major birth defects, using the total number of live births by sex during these years as the denominator. For each specific defect, we calculated a relative risk with regard to sex on the basis of the ratio of prevalence among males to prevalence among females. Male-female relative risks were also determined for total major birth defects and for several broad categories of defects. RESULTS: The overall prevalence of major defects at birth was 3.9% among males and 2.8% among females. All but two of the major categories of birth defects (nervous system defects and endocrine system defects) had a higher prevalence among males. Defects of the sex organs were eight and one-half times more prevalent among males and accounted for about half of the increased risk of birth defects among males relative to females. Urinary tract defects were 62% more prevalent among males, and gastrointestinal tract defects were 55% more prevalent among males. Among specific defect types, twofold or greater differences in prevalence by sex were common. CONCLUSIONS: Our data indicate that sex differences in the prevalence of specific human birth defects are common, and male infants are at greater risk for birth defects than female infants. Several mechanisms have been proposed to account for these differences.     

Physician-assisted deaths under the euthanasia law in Belgium: a population-based survey

Background

Legalization of euthanasia and physician-assisted suicide has been heavily debated in many countries. To help inform this debate, we describe the practices of euthanasia and assisted suicide, and the use of life-ending drugs without an explicit request from the patient, in Flanders, Belgium, where euthanasia is legal.

Methods

We mailed a questionnaire regarding the use of life-ending drugs with or without explicit patient request to physicians who certified a representative sample (n = 6927) of death certificates of patients who died in Flanders between June and November 2007.

Results

The response rate was 58.4%. Overall, 208 deaths involving the use of life-ending drugs were reported: 142 (weighted prevalence 2.0%) were with an explicit patient request (euthanasia or assisted suicide) and 66 (weighted prevalence 1.8%) were without an explicit request. Euthanasia and assisted suicide mostly involved patients less than 80 years of age, those with cancer and those dying at home. Use of life-ending drugs without an explicit request mostly involved patients 80 years of older, those with a disease other than cancer and those in hospital. Of the deaths without an explicit request, the decision was not discussed with the patient in 77.9% of cases. Compared with assisted deaths with the patient’s explicit request, those without an explicit request were more likely to have a shorter length of treatment of the terminal illness, to have cure as a goal of treatment in the last week, to have a shorter estimated time by which life was shortened and to involve the administration of opioids.

Interpretation

Physician-assisted deaths with an explicit patient request (euthanasia and assisted suicide) and without an explicit request occurred in different patient groups and under different circumstances. Cases without an explicit request often involved patients whose diseases had unpredictable end-of-life trajectories. Although opioids were used in most of these cases, misconceptions seem to persist about their actual life-shortening effects.Euthanasia and physician-assisted suicide are heavily debated issues in medical practice. In recent years, three European countries (Belgium and the Netherlands in 2002, and Luxemburg in 2009) and two US states (Oregon in 1997 and Washington State in 2009) decriminalized euthanasia and physician-assisted suicide under formal conditions.^1–5 Canada is among a number of countries where the debate over legalization has flared up, with a proposed bill reaching Parliament and a pro-euthanasia proposal by the Quebec College of Physicians.⁶Understandably, the issue of euthanasia triggers much emotion and can be fraught with speculative arguments. Opponents of euthanasia often argue that legalizing the procedure will lead to a rise in the use of life-ending drugs without a patient’s explicit request, especially in vulnerable patient groups.^7–10 Thus far, however, no indications of this have been found in studies of physician-assisted deaths before and after legalization in Belgium and the Netherlands.^9,11,12 In Belgium, the percentage of deaths in which life-ending drugs were used remained stable, and the proportion without an explicit request from the patient decreased.¹² Other studies have shown that euthanasia, physician-assisted suicide and the use of life-ending drugs without explicit patient request are not confined to countries where physician-assisted death is legal.^13–16In addition to knowing the overall occurrence of physician-assisted death, it is equally important for an adequately informed, empirically based debate to know its performance in vulnerable patient groups and the care put into the decision and performance. In light of legalization and its alleged effects on the use of life-ending drugs without patient request, it is also important to map similarities and differences between euthanasia and the use of life-ending drugs without explicit patient request. In this article, we report our investigation of demographic and clinical characteristics associated with physician-assisted deaths in Flanders, Belgium; the involvement of the patient, relatives and other caregivers in the decision-making process; reasons for the decisions; aspects of the treatment trajectory; and details of the performance in terms of drug use and the people administering the life-ending drugs.     

Trauma and Humanitarian Translation in Liberia: The Tale of Open Mole

The focus of this paper is the intercultural process through which Open Mole and trauma-related mental illnesses are brought together in the postconflict mental health encounter. In this paper, I explore the historical dimension of this process by reviewing the history of Open Mole, and the ways in which it has been interpreted, acted on, and objectified by external observers over the last half-century. Moving into Liberia’s recent war and postconflict period, I examine the process by which Open Mole is transformed from a culture-bound disorder into a local idiom of trauma, and how it has become a gateway diagnosis of PTSD-related mental illnesses, and consider how it is produced as an objectified experience of psychiatric disorder in clinical humanitarian contexts. By studying how Open Mole is transformed in the humanitarian encounter, I address the structure and teleology of the humanitarian encounter and challenge some of the foundational assumptions about cultural sensitivity and community-based mental health care in postconflict settings that are prevalent in scholarship and practice today.