Pediculosis capitis among primary and middle school children in Asadabad, Iran: An epidemiological study

Comparing the efficacy of three methods of permethrin application in pediculosis capitis: A randomized clinical trial

BACKGROUND

Pediculosis capitis, also known as head lice, is a common problem that affects individuals of different socio-economic backgrounds. Permethrin is generally considered the first-line treatment option for head lice.

AIMS

The objective of this study was to evaluate and compare the therapeutic effects of three different methods of permethrin treatment for head lice.

METHOD

A parallel, randomized clinical trial was conducted on 157 patients with head lice. The participants underwent eye examination and dry combing by a trained professional. The subjects were randomly divided into three groups and treated with one of the three methods of permethrin application: permethrin shampoo for 10 min, permethrin shampoo for 1 h, or permethrin cream for 10 min on a weekly basis for 3 weeks.

RESULTS

Of the 157 participants, 154 completed the study. The group treated with permethrin shampoo for 1 h had the shortest average time for eradication of lice at 1.226 ± 0.422 weeks, which was significantly lower than the other two groups. Additionally, the 1-h permethrin shampoo group had the lowest time for scalp itching of 2.15 ± 0.632 weeks, which was significantly lower than the other two groups. Moreover, the rate of lice eradication in the first week was significantly higher in the 1-h permethrin shampoo group.

CONCLUSION

The results of this study suggest that the use of 1% permethrin shampoo for 1 h is more effective in eradicating head lice within the first week of treatment and in relieving scalp itching during the second week.

Over-the-counter Pediculus humanus capitis treatment: The nit comb is not appropriate for all hair types!

Biological diversity of hair affects what stress the hair can withstand. This proves to create a gap in care when evaluating over-the-counter (OTC) products available to treat Pediculus humanus capitis (head lice) in the United States. The nit comb would not be conducive for use in an individual with African hair, yet all OTC product instructions list the requirement of the nit comb. Lice treatment products provide instructions that are applicable for only specific hair types and do not address treatment recommendations for African hair. The OTC product instructions are outdated and exclusionary. A clear discrepancy and gap in care exist for many Americans seeking self-care treatment of pediculosis capitis. Pharmacists should remain aware of this discrepancy and counsel on alternative practices such as applying the active formulations in the hair but refrain from using the nit comb following the application of the topical medication.

Children’s Perception Scale of Head Lice Infestation (CPS-HLI): Design and Psychometrics

Background: Pediculosis is a common ectoparasitic infestation that involves especially the skin of children worldwide. Studying the children’s perception of the disease’s risk factors, the effectiveness of personal preventive measures, and its implications for their health could be a major leap forward in health promotion activities. Objectives: This study aimed to develop and evaluate the psychometric properties of the Children’s Perception Scale of Head Lice Infestation (CPS-HLI) and its initial feasibility assessment for use on Iranian and possibly other elementary school children. Methods: The scale’s items were retained based on an extensive literature search and classified into the underlying constructs of the extended health belief model (EHBM). An expert panel endorsed the qualitative content and face validity of the preliminary draft, and 47 items remained for quantitative validity testing on a sample of 362 elementary school students in the city of Paveh, West of Iran. Explanatory and confirmatory factor analyses (EFA and CFA) were employed to test the content and structural validity of the constructed instrument. Cronbach's alpha and intra-class correlation coefficients were calculated to assess the internal consistency and reliability of the scale. Results: The values of Lawshe's content validity index (0.90) and content validity ratio (0.77), the subscales’ Cronbach's alpha (0.59), and intra-class correlation (0.72) coefficients confirmed plausible internal consistency of the scale. The values of root mean square error of approximation (RMSEA) (< 0.08 with χ2 < 0.05), Tucker-Lewis index (TLI), and comparative fit index (CFI) > 0.9 approved the applied statistical model’s goodness of fit. The ranges of Kaiser-Meyer-Olkin (KMO) measure of sampling adequacy for the underlying subscales (0.49 - 0.74) and the statistically significant result of Bartlett’s test of sphericity (P < 0.001) confirmed the patterned relationship among the constructed scale’s items. The principal component analysis that was performed using STATA favored the 11-factor solution. Conclusions: The study findings support the construct validity of CPS-HLI for use in studies on children’s perception of head lice infestation risk factors, the effectiveness of personal preventive measures, and the disease implications for their health and well-being. Further cross-cultural and cross-national validation studies are recommended for using the instrument in a wider range of populations and settings.

Diversity of mitochondrial genes and predominance of Clade B in different head lice populations in the northwest of Iran

BACKGROUND

The head louse, Pediculus humanus capitis, is the most important ectoparasite causing many health problems. Several linkages are presented for this parasite, each representing a particular geographical distribution, prevalence rate, vector competence, susceptibility to pediculicides, and infestation rate. Determining the genetic nature of these linkages is necessary to identify the population structure and also to develop and monitor control programmes against head lice. This study was designed to analyse cox1 and cytb genes and determine the mitochondrial clades in head lice populations in the northwest of Iran.

METHODS

Adult head lice were collected from infested females of Ardabil, East and West Azerbaijan, and Zanjan Provinces from 2016 to 2018. Partial fragments of the mitochondrial genes cox1 and cytb were amplified by PCR and some of the amplicons were sequenced. All confirmed sequences were analysed, and the frequency of each mitochondrial clade was determined in the studied areas.

RESULTS

A total of 6410 females were clinically examined, and 897 adult head lice were collected from 562 infested cases. Genomic DNA was extracted from 417 samples, and fragments of cox1 and cytb genes were amplified in 348 individuals. Analysis of the 116 sequences showed the 632-bp and 495-bp fragments for cox1 and cytb genes, respectively. The nucleotide and haplotype diversities of cytb and cox1 genes were 0.02261 and 0.589 and 0.01443 and 0.424, respectively. Sequence analysis indicated 6 haplotypes clustered in two clades, A and B. The relative prevalence of clade B was 73% for cytb and 82% for cox1 gene. Haplotypes of clade B were found in all the studied areas, while those of clade A were observed only in rural and suburban areas.

CONCLUSIONS

To our knowledge, this is the first study investigated deeply the field populations of Pediculus and documented two clades in the Middle East. The considerable prevalence of pediculosis in the studied areas requires authorities' attention to establish effective control and preventive measures. Given the role of cytb in monitoring population groups, application of this marker is suggested for future epigenetic studies to evaluate the factors affecting the abundance of these clades.

Investigation of the prevalence of Head Lice and Factors Affecting Them in Infected People Referring to Gerash County Health Center

Background and aims: Pediculosis is one of the most common parasitic diseases that affect a wide range of age groups. The prevention of head lice infections promotes the physical and mental health of people in the community. Thus, the aim of this study was to investigate the prevalence of head lice infections and the factors affecting them in those who referred to health centers in Gerash County from 2011 to 2018. Methods: This descriptive cross-sectional study was conducted on patients suspected with head lice infections in health centers in Gerash. These infections were diagnosed by observing adult lice, nymphs, or nits on the head with the help of a magnifying glass. The collected data were then analyzed using SPSS software, version 22 and P˂ 0.05 was considered as the significance level. Results: In general, 66410 patients suspected with head lice were examined, of whom 2,547 cases (3.83%) were reported with confirmed infections including 2395 female (94.03%) and 152 male (5.97%) cases. The highest levels of infections were reported in the age group of 6-10 years while the lowest levels of infections were found in children less than 6 years of age. A significant statistical relationship was observed between head lice and gender, age, season, and the place of residence, and year of infection (P<0.05). Conclusion: Due to the increasing trend of head lice infections in recent years, pediculosis is still considered a health problem. Therefore, training on personal hygiene, adequate access to health services, and early diagnosis and treatment can play an important role in the prevention and elimination of head lice.

Prevalence of pediculosis capitis and associated factors among schoolchildren in Woreta town, northwest Ethiopia

Objectives

The aim of the study was to determine the associated risk factors and prevalence of pediculosis capitis among school-aged children in Woreta town, northwest Ethiopia. An institution-based cross-sectional study was carried out on 402 schoolchildren in Woreta town public schools from grades 1 to 4 students conducted from April to June 2018. After selection by simple random sampling, face to face interview and observations were performed using a semi-structured pre-tested questionnaire. Data were entered into EPI Info 7 and exported to SPSS 21 for further analysis. Descriptive results were presented by simple frequency, percentage, and mean. Binary logistic regression was used to identify associated factors. Those variables with a p-value ≤ 0.05 in the multivariable logistic regression were declared as significantly associated with pediculosis capitis infestation.

Result

The prevalence of pediculosis capitis was 65.7% [95% CI 60.01–70.3%]. Sex of child, age of the child, maternal education, sharing hair comb, knowledge, and attitude towards pediculosis capitis infestation and hygiene practice were significantly associated with pediculosis (a p-value ≤ 0.05). Pediculosis infestation is found to be a major public health problem which demands special attention of the community and the government at large particularly the health sector to reduce the problem.