Abstract

Background: Head lice (Pediculus humanus capitis) are common, blood-sucking ectoparasites that infest the human scalp, with significant public health relevance, particularly among school-aged children. Specific Background: These wingless insects, belonging to the order Phthiraptera, are highly transmissible in dense environments such as schools. Knowledge Gap: Despite global awareness, there is limited region-specific data on infestation prevalence and contributing factors in northern Iraq, particularly in Kirkuk City. Aim: This study aimed to determine the prevalence of pediculosis and identify associated sociodemographic and behavioral risk factors among schoolchildren in Kirkuk. Results: Visual inspections of 300 pupils from five schools revealed an overall infestation rate of 10.3%, with higher prevalence among females (13%) compared to males (4.44%). Children aged 6–12 and those in lower educational levels exhibited significantly higher infestation rates. Behaviors such as sharing combs and clothing were also associated. Novelty: This is the first extended surveillance-based study in Kirkuk that combined clinical inspection with behavioral questionnaires over a full year. Implications: Findings underscore the need for enhanced school-based health education, early detection, and hygiene practices to mitigate the spread of pediculosis. Regional strategies should incorporate community involvement and consistent provision of preventive treatments.

Highlights:

1. High-risk group: Females and children aged 6–12 most affected.

2. Transmission factors: Sharing combs, clothes, and beds increases risk.

3. Prevention focus: Health education and treatment programs are essential.

Keywords: Pediculosis, Head lice, Schoolchildren, Prevalence, Public health

Introduction

The largest class in the kingdom of Animalia is insects. Insects made up to 80% of all known animal species worldwide [1]. countries globally. In addition to head lice's capacity for quick spread, this issue is also belongs to head lice resistance that arises from insufficient or inappropriate treatment. Human head lice, or Pediculushumanuscapitis, are obligate ectoparasites that are wingless and bloodsucking. They belong to the Phthiraptera order and are specific parasites of humans [2]. They have three life stages: egg, nymph, and adult. Adult louses can live up to 30 days on a person's head, lay up to 10 eggs each day, and feed on blood multiple times a day, though they can occasionally go 36 hours without feeding. Although they are not known to spread any diseases, they are known to irritate, annoy, and make people sleepy [3]. Millions of children worldwide are impacted by this common community health issue, which can be entirely asymptomatic or result in severe symptoms such as dermatitis, allergic reactions, pruritus, excoriation, lymphadenopathy, conjunctivitis, extreme scalp itching, and secondary bacterial infections. Sensitization to the salivary and fecal antigens of lice causes pruritus, which can be so severe that it can lead to subsequent bacterial infection [4]. Direct hair contact with an infected person can transmit head lice to humans. Transmission occurs between family members and between youngsters when they play, cuddle, or work closely together [5]. Children between the ages of five and twelve have the highest rate of infection , but the group between the ages of 24 and 36 has the highest prevalence because they are exposed to infected children. The socioeconomic status, lack of access to healthcare, and inadequate sanitation are the main causes of this infection in this group [6]. In the United States of America, six to twelve million people are afflicted with pediculosis capitis annually [7]. The frequency of pediculosis infestation in children in Ilorin, Nigeria, was 3.7%, with females being more likely than males to have it (5.6%) [8]. In Taiwan, the prevalence was 12.9%, whereas in eastern Korea, it was 5.8% [9]. Epidemiological studies conducted in a number of schools and nurseries in neighboring Arab and Iraqi countries found that the incidence rate of infestation was 9.4% in Turkey, 4% in Iran, and 14% in Iraq [10,11]. A significant public health concern that is especially common in areas with low resources [12,13].

Methods

Five schools in Kirkuk, Iraq, in the north of the country, participated in the study. The data obtaining and sampling, Regular visits were made to the schools twice a week between December 2023 and November 2024. The entire head of each interviewee was visually inspected for head lice infestation throughout the quick interview, with particular care given to the back of the ears and nape of the neck. Hair with nits left over and at least one stage of pediculosis capitis development was considered infested. therefore,we examines carefully observed the nits to increase the accuracy of the diagnosis. Typically, P. humanus capitis adult females spawn nits within 6 mm from the scalp [14]. Information on age, sex, school grade, frequency, sharing a common comb, and a common clothes or beds, and duration of infestation was collected via a questionnaire after the head inspection. People who were infested were then told about anti-lice shampoo and given tips on how to manage the illness.

Result and Discussion

Result

210 female and 90 male students out of 300 were visually inspected for head lice (P. humanus capitis). P. humanus capitis infestations were discovered in about 31 students (10.3%), with female students having a greater infestation rate than male students (Table 1). from the total number of student four infected males with rate (4.44%) and 27 females infected with rate (13%).

Table-2 provides the number of cases and percentage of pediculosis in each age of school childern group. The infection rates were higher among the 6–12 age group (20%) than among the other age groups, followed by the 12–15, 3–6, and more than 18 age groups (6.7% and 3.3%, respectively).

According to the current study's findings, a considerable portion of the student body is affected by the infestation. Kids aged 6 to 12 who were seated in classes with more than 60 kids had a higher infestation rate (20%) than students of other ages.

Discussion

A significant worldwide concern is head lice (Pediculushumanuscapitis), and there is mounting evidence that their frequency is rising among schoolchildren [15]. It is characterized by the existence of a minimum of one surviving adult, nymph, or viable nit. One of the most significant obligate ectoparasites that infest humans are head lice, which can range in prevalence from less than 1% to over 50% depending on the country[16]. Despite the significance of louse infestation for public health, little is known about the epidemiological landscape of louse-borne diseases and the worldwide burden of pediculosis [17]. Due to inadequate service and poor sanitation, the majority of students in Kirkuk, Iraq, are the subjects of the current study. The overall prevalence of pediculosis among Kirkuk-Iraqi students was 10.3%, which is less than some student surveys have found. According to a recent study conducted in Kut, the infection rates among schoolchildren were 13.3% for boys and 21.8% for females [18]. The variation in age could be the cause of the greater infection rate. Most research focuses on schoolchildren [19]. Poland conducted a poll from 2014 to 2018. There were reports of pediculosis capitis in 87.5% of the schools. A study in Thailand reveals The primary school level had the highest infestation rate (87.5%), Infestation rates among Saudi schoolchildren were Among participants, females had a greater infection rate (94.08%) than males (5.91%) [20]. In Egypt, schoolchildren had a high prevalence of pediculosis (54.1%), in the same study in Iran, the infestation rate was 6.85% [21], while in Palestine the rate reaches 14.1% [22], all these results were higher in comparison with Socioeconomic, cultural, environmental, and climatic factors contributed to the prevalence of pediculosis among the kids in the current study. Additionally, as primary school students are at a vital age for personal cleanliness, the majority of pediculosis research done in Iraq concentrated on them. According to a study conducted in Kirkuk province, Iraq, among elementary school students, the prevalence of pediculosis infestation was 6.5% [23]. This variation in the prevalence of head lice infection may be caused by a variety of factors, including head-to-head contacts, diagnostic techniques, eradication methods, pesticide resistance, head lice education, and the perception of pediculosis as a health problem [24].The season, lack of access to quality of medical care, insufficient sanitation and socioeconomic status, and the use of inferior anti-lice shampoo that is sold commercially because pediculosis is out of control are some other factors that contribute to the increased prevalence of parasitic infections and head pediculosis. the use of emerging omics technologies (genomics, transcriptomics, proteomics, and metabolomics) to elucidate the mechanisms that underpin the physiological, ecological, and evolutionary aspects of lice, In the current study, the infestation rate among female was significantly higher than in male, which was consistent with many other studies [25]. The behavioral differences between the sexes could be the cause of this. In general, girls have longer hair than boys, and guys tend to make brief touch during rough or athletic activity. The incidence of head lice was significantly correlated with age; in the current study, the highest infestation rate (20%) was seen in those aged 6–12, followed by those aged 12–15. This finding was consistent with [26]. in Al Kut city , Personal hygiene habits, such as routinely combing and washing one's hair, as well as activities, may be the cause of the variance in infestation rates among age groups [27]. Children may have a higher infestation incidence since they engage in more activities and are likely to rely on one another for personal cleanliness. However, due to their higher level of health education and occasional independence, adults above the age of 18 had a lower infection rate [28]. In the case of schools, the majority of the packed classrooms were seated together in a common area, interacting with one another and sharing resources. The majority of students wash their hair and take a bath once a week, particularly during the winter, due to This trait has the highest rate of infestation among them because to the cold weather, which may be connected to these disputes. Furthermore, according to certain research, hair length did not seem to be a risk factor in and of itself [29,30]. But according to other research, girls with longer hair had higher lice infestations [31,32]. The results can be explained by the fact that most students have similar hair types and, due to their lifestyle choices, do not have long hair. There was no clear correlation between pediculosis infestation and scalp illness in the current research..

Conclusion

Pediculosis is a global public health concern among students, according to the study's findings. The low prevalence rate may be attributed to routine health education programs that involve parents and schools monitoring students and providing anti-lice shampoo to prevent and reduce infestation.

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