The impact of COVID-19 pandemic on the prevalence of head lice infestation among children attending schools and kindergartens: direct research in Poland.

doi:10.21203/rs.3.rs-1541287/v1

PDF

Article

The impact of COVID-19 pandemic on the prevalence of head lice infestation among children attending schools and kindergartens: direct research in Poland.

https://doi.org/10.21203/rs.3.rs-1541287/v1

This work is licensed under a CC BY 4.0 License

You are reading this latest preprint version

Human pediculosis is a parasitic disease caused by Pediculus humanus. The infection occurs mainly among children aged 5 to 13 years old. Due to the high prevalence of Pediculus humanus in the environment and the parasite's ability to transmit pathogenic bacteria, the disease needs monitoring. Each year, nearly 12 million patients suffer from head lice infestation. Current recommended treatment includes topical antiparasitic agents, oral therapy, and combing. The infestation causes potential social side effects such as embarrassment, discomfort, and necessary absenteeism from school or kindergartens. Various types of restrictions were used in Poland during the COVID-19 pandemic since 2020, including restrictions on interpersonal contacts, social isolation and functional restrictions on educational facilities. The aim of this study was to evaluate the relationship between COVID-19 pandemic and the prevalence of head lice among children attending schools and kindergartens in Poland. The study group consisted of children aged 3 to 14 years old attending elementary school and kindergartens. A total of 5008 children were examined in educational institutions by registered nurses in period of 35 months. The results indicated that the restrictions applied during the COVID-19 pandemic reduced significantly the number of infected school children comparing to the pre-pandemic state. At the same time, restrictions and functional limitations of educational facilities did not significantly affect the incidence of head lice among preschool children. It can be concluded that restrictions on direct human contacts also significantly reduced the incidence of human head lice infestation among the study population.

head lice infestation

pandemic

COVID-19

Human head lice (lac. Pediculus humanus) are ectoparasites of humans [1, 2]. They are wingless insects that remain near the human scalp throughout their lives as obligate blood-sucking arthropods. The life cycle of Pediculus humanus consists of three stages: the adult form, the nymph and the egg and lasts about three weeks. Nymphs, like the adult forms, live on human scalp and feed on blood at each stage of development [2–5]. A single copulation allows females to lay 50–150 eggs in 16 days of the lifecycle. Mature forms live about a month. During this time, they live on the host's head, migrate to other hosts, feed on blood, reproduce and lay eggs [2].

The route of transmission of head lice is direct, from host to host, during close contact, or indirect, through shared headgear or hair accessories. Therefore, infection most often occurs in the household, between family members. The risk of infection also exists in crowded public places [3, 6, 7]. However, the most vulnerable group are children attending schools and kindergartens. The main risk group for head lice infestation are children aged between 5 and 13 years old due to their social, group lifestyle [8–12]. The most common symptom of head lice infestation for humans is itching of the scalp. In addition, symptoms such as inflammation, skin redness, pain, erythema, scaling and burning, secondary infections (bacterial, fungal), pyoderma, lymphadenopathy, conjunctivitis, and even fever, anemia, insomnia and malaise can occur [3, 13]. The infestation can remain asypthomatic [14, 15]. Acting as a vector, Pediculus humanus can also transmit pathogens such as Rickettsia prowazekii, Borrelia recurrentis, Bartonella quintana, and Acinetobacter baumannii [2, 16, 17]. Head scratching and shaking are common symptoms due to pruritus. The most effective diagnosis of head lice infestation is based on visual inspection and the presence of trophic forms and/or eggs. Eggs are most often deposited on the back of the head and behind the ears but can be also found all over the head. Practice shows that the detection of trophic stages, mainly during low intensity infestations, is not diagnostically significant. However, a case is considered positive when any stages or even parts of the parasites are found [1, 18, 19].

Treatment of the head lice infestation should only take place after a proper diagnosis has been made. In addition, anyone who had contact with the infested person should be verified for the presence of eggs or trophic stages. Additionally, all items that have been in contact with the head within the last 48 hours should be washed or frozen. The use of head lice control products as a preventative measure can irritate the scalp and cause itching, which can cause a false positive diagnosis. There are three methods of controlling head lice: combing, using killing products and/or oral medications [20–23]. For this purpose, the most effective products are those containing compounds from the silicone group - cyclomethicone and dimethicone. These compounds tightly cover the bodies of parasites, penetrate the crevices, and block the respiratory system, as well as cause disruption of water balance, thereby inactivating trophic forms of lice. The most effective method of pediculosis control is a combination of combing out and applying a killing agent [20, 22, 24–26]. Due to the structure of the eggs, no single product can have lethal effects. Therefore, the only way to be sure that treatment will be effective is to mechanically remove all the eggs from the hair. It is commonly believed that preparations based on compounds from the pyrethroid group are the most effective. However, practice begins to show that these substances are less and less effective. Studies show that human lice have developed defence mechanisms and have become resistant to neurotoxin and permethrin [27, 28]. Prophylactic measures consist of hair tying and using scented repellents against live mature forms [29].

The wide spread of head lice is evidence of the expansion of the African population about 100.000 years ago [5]. Today, head lice is found worldwide, crossing all social and economic boundaries [3]. The intensity of infestation is greater during the warmer months [30–32]. In the United States of America (USA), head lice is the most common among preschool children, elementary school students and members of households with children. Although there is no reliable data on the number of people infested with head lice in the USA, it is estimated that the number of infestations among children aged 3 to 11 years old is between 6 and 12 million yearly [14, 33]. In the United Kingdom (UK), head lice infestation is the most common among children aged 4 to 11 years old, while it is most diagnosed among children aged 7 to 8 years old. In China, where 303 school-aged children were surveyed in 2004, 43 (14.2%) were affected by head lice [34]. In India, the prevalence of head lice was checked between 2002 and 2004. Of 150 children working and living in slums, 72 (48%) were infested. Of 940 (16.59%) children attending public elementary schools, 156 students had head lice [35]. In Latin America, 30–50% of school-aged children are infested with head lice [1]. In Argentina, in 2003, 1.370 children attending private and public elementary schools were checked and lice were detected in 842 (61.4%) [36]. In the Czech Republic, between 2004–2005, 531 children were tested in 2006 and 127 of them had lice or nits on their heads [37]. These statistics clearly show that the problem is worldwide and that economic and social status is irrelevant to head lice infestation. Data from the study conducted between 1996 and 2000 in Lubelskie Voivodship, Poland, indicated that of 42.759 girls, only 682 were infested with head lice (1.59%), and of 52.394 boys, 252 (0.48%) were infested [38, 39]. Head lice infestations in Poland are not subject to sanitary surveillance, meaning that there is no obligation to report cases of head lice to the National Sanitary Inspectorate. It is therefore not possible to estimate the scale of the problem due to the lack of a national data collection system. Therefore, it was not possible to estimate the impact of the COVID-19 pandemic on the incidence of head lice due to the lack of current data on the number of infections in Poland in recent years. On the other hand, there are only a few studies from the other countries that focused on the impact of the COVID-19 pandemic and its limitations on the incidence of lice.

Methods such as social distance, isolation, quarantine, sanitation regime, and closure of public places such as schools and kindergartens have been used to reduce the spread of COVID-19 disease worldwide. After the first case of COVID-19 in Poland, that was declared on March 4, 2020, the government began to use measures to limit the development of the pandemic, such as online teaching and closing kindergartens. Regardless of the severity of the pandemic, all educational institutions have been operating under a sanitary regime. Head lice in humans are transmitted from host to host primarily during direct contact, so measures to reduce the COVID-19 pandemic may also have influence on the number of lice infestations among children.

The aim of this study was to determine the association between pandemic infectious disease COVID-19 caused by coronavirus SARS-CoV-2 and the incidence of human head lice infestation caused by Pediculus humanus among children attending schools and kindergartens in Poland.

2.1 Comparison of lice infestation among children attending kindergartens before and during the COVID-19 pandemic

The pre-COVID study covered the period from September 24, 2018 to February 28, 2020. During this time, 2.060 children were screened, of which 256 were infected with head lice. The COVID-19 pandemic period of the study began on September 14, 2020 and ended on July 29, 2021. During this period, 1.195 children were screened, of which 104 were infected with head lice. The above data are shown in Figs. 1–4 and Table 1.

Table 1

Statistical analysis of the number of lice [per 100 children] depending on the period of the COVID-19 pandemic in kindergartens.
Descriptive statistics		Kindergarten
Descriptive statistics		Before COVID-19 pandemic	During COVID-19 pandemic
Average		12.06	9.75
Median		9.03	6.42
Standard deviation		8.45	9.91
Minimum		0	0
Maximum		31.82	43.48
Lower quartile		5.93	3.14
Upper quartile		19.01	16.83
U Mann-Whitney Test	Z	1.49
U Mann-Whitney Test	P	0.14

The presented results indicate that number of infected children in kindergartens during the COVID-19 pandemic decreased by 30% compared to the number before the COVID-19 pandemic. However, this decrease was not statistically significant. In kindergartens, the number of lice [per 100 children] did not change significantly (p > 0.05) according to the COVID-19 pandemic period.

2.2 Comparison of lice infestation among children attending schools before and during the COVID-19 pandemic

The pre-COVID study covered the period from September 4, 2019 to March 10, 2020. During this time, 1.027 children were screened, of whom 145 were infected with head lice. The COVID-19 pandemic period, during which research was conducted, began on September 24, 2020 and ended on June 17, 2021. During this period, 726 children were screened, of which 42 children were infected with head lice. The above data are shown in Figs. 5–8 and Table 2.

Table 2

Statistical analysis of the number of lice [per 100 children] depending on the period of the COVID-19 pandemic in schools.
Descriptive statistics		School
Descriptive statistics		Before COVID-19 pandemic	During COVID-19 pandemic
Average		10.47	5.37
Median		9.95	4.52
Standard deviation		6.33	5.55
Minimum		0	0
Maximum		21.67	17.20
Lower quartile		7.79	0.26
Upper quartile		13.44	8.00
U Mann-Whitney Test	Z	2.11
U Mann-Whitney Test	P	0.04

The presented results show that the number of infected children in kindergartens during the COVID-19 pandemic decreased by 55 % compared to the number before the COVID-19 pandemic. This decrease was statistically significant.

The impact of the COVID-19 pandemic on the incidence of head lice infestation has been not studied in Poland and just poorly studied in other countries. Studies published on this topic so far utilized either indirect methods of lice verification, which are less precise and reliable than direct methods used in this study or were performed on the significantly smaller study population and area [32, 40].

The cross-sectional descriptive study performed by Galassi F. et al. used an online survey to determine the effect of isolation on the incidence of head lice during quarantine and before the pandemic in Argentina, Buenos Aires. Data from 1118 children obtained from 627 surveys was analysed. They found that the overall prevalence of head lice decreased significantly from 69.6% before the COVID-19 pandemic to 43.9% during the COVID-19 pandemic. In addition, head lice infestation was more effectively controlled in households with up to two children than in households with three or more children. The restrictions that were applied consisted of the interruption of regular activities that directly affected contact between children, and thus the spread of head lice infestation. Despite this was the first study examining the prevalence of head lice among children during the COVID-19 pandemic, confirmation pediculosis prevalence was conducted using a survey among parents. Indirect methods, as surveys, are always subject to greater error than direct detection performed by properly trained personnel. Additionally, the analysed group of 1118 children were almost five times smaller than the group of children examined in Poland during this study [40].

Further indications of the impact of global isolation on the prevalence of head lice infestations among children have come from the United States (USA). The article published in 2021 considered the prevalence of head lice among school-aged children before and during the COVID-19 pandemic. The situation in the USA was different from that in Argentina. A significant increase in the number of diagnosed cases of head lice infestation was observed during the lockdown period, in 2020. Head lice clinics in the USA reported increase in the number of head lice infestations in the spring of 2020 by an average of 25% over pre-pandemic COVID-19 values. Head lice infestations affected entire families and were more severe during the pandemic due to prolonged cohabitation in households. The presented results suggest that the epidemiology of head lice infections in the USA may base on a different mechanism than in Argentina and Poland. In the USA, head lice infestation was effectively spread within homes. In contrast, in Argentina and Poland, the spread of head lice occurs mainly outside the households, mainly in places where there are many children at the same time such as educational institutions. Texas, California, Louisiana, and Kansas have seen even greater increases in head lice infestations, up to 50% compared to data prior to the COVID-19 pandemic. The numbers reported based on reports from 112 out of 200 clinics opened in April and May 2020. The stay-at-home order has resulted in the spread of head lice infestation among households [41].

The effect of lockdowns on the spread of head lice infestation was tested also in France. A population-based study was conducted by the indirect method of monitoring the sale of anti-lice drugs. The study period was 5 years including periods before and during the COVID-19 pandemic. Analysis of the database of health care science company, IQVIA Pharmaone LMPSO, which covers 14.000 pharmacies in France was utilized. A clear decrease in sales, up to 50%, of topical anti-lice drugs and less significant decrease in sales of ivermectin was observed during the periods of national isolation. However, other treatment options for lice infestation such as combing were not explored in this study. Additionally, the anti-lice treatments sold online were not included in the database [32].

In our study we directly examined 5108 children from educational institutions. we revealed that number of infected children in kindergartens decreased by 30% (statistically insignificant value) and in schools by as much as 55% (statistically significant value). The difference may result from the different mode of operation of both institutions. Generally, schools switched into remote mode of education earlier and stayed on this mode longer than kindergartens. The data presented in our study correlate with data obtained in Argentina and Australia and clearly indicate that the restrictions applied during the COVID-19 pandemic reduced the rate of lice infestation among children. However, restrictions applied during the COVID-19 pandemic in the USA resulted in the spread of head lice within households and between family members, which was not the case in Argentina and Poland.

To our knowledge, this is the very first study worldwide, where the impact of the COVID-19 pandemic on the incidence of head lice among children has been verified using a direct method of examination performed on such a large children population.

The presented study demonstrated a strong relationship between the incidence of head lice infestation among school and preschool children and the COVID-19 pandemic period. Restrictions applied during the COVID-19 pandemic on interpersonal contact limited the spread of head lice infection among school-aged children. At the same time, restrictions and functional limitations of educational facilities did not significantly affect the incidence of head lice among preschool children. Statistical analysis of the available data suggests that the main route of the spread of head lice among children in Poland is close group contact between peers, rather than between family members. Obtained data also confirm, that head lice infestations are still current epidemiological problem in developed countries and need consistent monitoring. In order to prevent pediculosis spread, regular head lice inspections in schools and kindergartens, performed by certified and experienced staff, should be an integral part of everyday life of those facilities.

5.1 Organization and conduct of the study

The study was conducted between the beginning of September 2018 and the end of June 2021. Each direct verification of the pediculosis was conducted in an educational institution - elementary school or kindergarten. Visits to schools and kindergartens were initiated by the management of the institution. The research was conducted by the certified nurse. Participation in the study was voluntary. The consent to conduct the study was given by the parents of the examined children and confirmed by the management of the educational institution. The study was carried out in 64 kindergartens and 28 elementary schools in Warsaw, Cracow and Poznan.. According to the decision no. AKBE/99/2021 of the Bioethics Committee of Medical University of Warsaw, per Polish law the study does not require favourable opinion of the Bioethics Committee. All research was performed in accordance with relevant guidelines/regulations.

5.2 Characteristics of the studied group

The study group consisted of children from 3 to 14 years old attending primary schools and kindergartens. 3255 children from kindergartens and 1753 children from primary schools were checked in case of head lice. A total of 5008 children were examined.

5.3 Human head lice infestation verification methods

The direct examinations were conducted by certified nurses equipped with specialized magnifying glasses and combs. Each child's hair was examined visually and combed if needed with an individual comb and then carefully examined under the magnifying glass. Head lice infestation was diagnosed based on lice, nymphs or nits found in the hair. The head lice infestation was confirmed based on individual and/or nit presence, regardless of their number found in the hair.

5.4 Statistical analysis

Statistical analyses were performed using the PQStat statistical package, version 1.8.2.192. The number of lice [per 100 children] depending on the period of the pandemic was compared with the Mann-Whitney U test. The test probability at the level of p < 0.05 was considered significant.

Author contributions

A.G.M carried out experimental studies. She also participated in drafting of the manuscript and figure preparation.

M.P, E.B.H, E.K and G.O was responsible for coordinating the experiments, critical assessment of results and wrote the main body text of the manuscript.

M.P was involved in critical review of the manuscript and supervision of on-going studies.

All authors reviewed the manuscript.

Competing interests

Authors declare no competing financial or non-financial interests.

Data availability

The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.

Ethics approval

This is an observational study. According to the decision no. AKBE/99/2021 of the Bioethics Committee of Medical University of Warsaw, per Polish law the study does not require favourable opinion of the Bioethics Committee.

Consent to participate

Informed consent was obtained from the parents.

Consent to publish

Not applicable.

Lustosa, B.P.R. et al. Vaccuuming method as a successful strategy in the diagnosis of active infestation by Pediculus humanus capitis. Rev Inst Med Trop Sao Paulo. doi: 10.1590/S1678-9946202062007 (2020).
Coates, S.J., Thomas, C., Chosidow, O., Engelman, D., Chang, A.Y. Ectoparasites: Pediculosis and tungiasis. J Am Acad Dermatol. doi: 10.1016/j.jaad.2019.05.110 (2020).
Ko, C.J., Elston, D.M. Pediculosis. J Am Acad Dermatol. 50, 1–4 (2004).
Bonilla, D.L., Durden, L.A., Eremeeva, M.E., Dasch, G.A. The biology and taxonomy of head and body lice–implications for louse-borne disease prevention. PLoS Pathog. 9, e1003724 (2013).
Arriaza, B., Standen, V., Nunez, H., Reinhard, K. Study of archaeological nits/eggs of Pediculus humanus capitis by scanning electron microscopy. Micron. 45, 145–149 (2013).
Chosidow, O. Scabies and pediculosis: neglected diseases to highlight. Clin Microbiol Infect. 18, 311–312 (2012).
Heukelbach J. et al. Orientation of Head Lice on Human Hosts, and Consequences for Transmission of Pediculosis: The Head Lice Movement Studies. Trop Med Infect Dis. 2, 10.3390/tropicalmed2020011 (2017).
Leung, A.K., Fong, J..H., Pinto-Rojas, A. Pediculosis capitis. J Pediatr Health Care. 19, 369–373 (2005).
Albashtawy, M. Pediculosis in School Sitting: What Is the Role of School Nurses? Iran J Public Health. 46, 1301–1302 (2017).
Baghdadi, H.B., Omer, E.O.M., Metwally, D.M., Abdel-Gaber, R. Prevalence of head lice (Pediculus humanus capitis) infestation among schools workers in the Eastern Region, Saudi Arabia. Saudi J Biol Sci. 28, 5662–5666 (2021).
Clark, J.M. New chemistries for the control of human head lice, Pediculus humanus capitis: A mini-review. Pestic Biochem Physiol. 181, 105013 (2022).
Catala, S. et al. Prevalence and parasitism intensity by Pediculus humanus capitis in six to eleven-year-old schoolchildren. Rev Soc Bras Med Trop. 37, 499–501 (2004).
Bloomfield, D. Head lice. Pediatr Rev. 23, 34–5 (2002).
Nutanson, I., Steen, C.J., Schwartz, R.A., Janniger, C.K. Pediculus humanus capitis: an update. Acta Dermatovenerol Alp Pannonica Adriat. 17, 147–7, 159 (2008).
Mumcuoglu, K.Y., Klaus, S., Kafka, D., Teiler, M., Miller, J. Clinical observations related to head lice infestation. J Am Acad Dermatol. 25, 248–251 (1991).
Robinson, D., Leo, N., Prociv, P., Barker, S.C. Potential role of head lice, Pediculus humanus capitis, as vectors of Rickettsia prowazekii. Parasitol Res. 90, 209–211 (2003).
Coulaud, P.J. Et al. Hemocytes from Pediculus humanus humanus are hosts for human bacterial pathogens. Front Cell Infect Microbiol. 4, 183 (2015).
Heukelbach, J., Walton, S.F., Feldmeier, H. Ectoparasitic infestations. Curr Infect Dis Rep. 7, 373–380 (2005).
Borges, R., Mendes, J. Epidemiological aspects of head lice in children attending day care centres, urban and rural schools in Uberlandia, central Brazil. Mem Inst Oswaldo Cruz. 97, 189–192 (2002).
Elston, D.M. Drugs used in the treatment of pediculosis. J Drugs Dermatol. 4, 207–211 (2005).
Feldmeier, H. Pediculosis capitis: new insights into epidemiology, diagnosis and treatment. Eur J Clin Microbiol Infect Dis. 31, 2105–2110 (2012).
Feldmeier, H. Treatment of pediculosis capitis: a critical appraisal of the current literature. Am J Clin Dermatol. 15, 401–412 (2014).
Gunning, K., Kiraly, B., Pippitt, K. Lice and Scabies: Treatment Update. Am Fam Physician. 99, 635–642 (2019).
Heukelbach J. et al. A highly efficacious pediculicide based on dimeticone: randomized observer blinded comparative trial. BMC Infect Dis. 8, 115–115 (2008).
Heukelbach J. et al. Ovicidal efficacy of high concentration dimeticone: a new era of head lice treatment. J Am Acad Dermatol. 64, 61 (2011).
Heukelbach, J., Asenov, A., Liesenfeld, O., Mirmohammadsadegh, A., Oliveira, F.A. A new two-phase dimeticone pediculicide shows high efficacy in a comparative bioassay. BMC Dermatol. 9, 12–12 (2009).
Dagrosa, A.T., Elston, D.M. What's eating you? head lice (Pediculus humanus capitis). Cutis. 100, 389–392 (2017).
Elston, D.M. Drug-resistant lice. Arch Dermatol. 139, 1061–1064 (2003).
Bohl, B., Evetts, J., McClain, K., Rosenauer, A., Stellitano, E. Clinical Practice Update: Pediculosis Capitis. Pediatr Nurs. 41, 227–234 (2015).
Mimouni, D. et al. Seasonality trends of Pediculosis capitis and Phthirus pubis in a young adult population: follow-up of 20 years. J Eur Acad Dermatol Venereol. 16, 257–259 (2002).
Amato, E. et al. Increase of scabies infestations, Norway, 2006 to 2018. Euro Surveill. 24, 10.2807/1560–7917.ES.2019.24.23.190020 (2019).
Launay, T., Bardoulat, I., Lemaitre, M., Blanchon, T., Fardet, L. Effects of the COVID-19 pandemic on head lice and scabies infestation dynamics: a population-based study in France. Clin Exp Dermatol. doi: 10.1111/ced.15135. Epub ahead of print. PMID: 35150155 (2021).
Chosidow, O. Scabies and pediculosis. Lancet. 355, 819–826 (2000).
Fan, P.C., Chung, W.C., Fan, C.K., Huang, P., Yen, C.W. Prevalence and treatment of Pediculus capitis infestation among aboriginal school children in northern Taiwan. Kaohsiung J Med Sci. 15, 209–217 (1999)
Khokhar, A. A study of pediculosis capitis among primary school children in Delhi. Indian J Med Sci. 56, 449–452 (2002).
Catala, S., Junco, L., Vaporaky, R. Pediculus capitis infestation according to sex and social factors in Argentina. Rev Saude Publica. 39, 438–443 (2005).
Rupes, V., Vlckova, J., Mazanek, L., Chmela, J., Ledvinka, J. Pediatric head lice: taxonomy, incidence, resistance, delousing. Epidemiol Mikrobiol Imunol. 55, 112–119 (2006).
Buczek, A., Kawa, I.M., Markowska-Gosik, D., Widomska, D. Pediculosis in rural schools of Lublin Province. Wiad Parazytol. 47, 359–364 (2001).
Buczek, A., Markowska-Gosik, D., Widomska, D., Kawa, I.M. Pediculosis capitis among schoolchildren in urban and rural areas of eastern Poland. Eur J Epidemiol. 19, 491–495 (2004).
Galassi F. et al. Head lice were also affected by COVID-19: a decrease on Pediculosis infestation during lockdown in Buenos Aires. Parasitol Res. 120, 443–450 (2021).
https://www.wrcbtv.com/story/42378418/head-lice-cases-rose-during-coronavirus-lockdown-clinics-say?fbclid=IwAR0XWAd8fdM2vgNdOqin7WlVuEJ85OfL83F-b-30GZwne7KAXnOH1n9GQm0 dostęp: 28 lipca 2021, godz. 20:40

No competing interests reported.

PDF

Editor invited by journal
27 Apr, 2022
Submission checks completed at journal
27 Apr, 2022
First submitted to journal
09 Apr, 2022

You are reading this latest preprint version

The impact of COVID-19 pandemic on the prevalence of head lice infestation among children attending schools and kindergartens: direct research in Poland.

Status:

Version 1

Abstract

Figures

1. Introduction

2. Results

2.1 Comparison of lice infestation among children attending kindergartens before and during the COVID-19 pandemic

2.2 Comparison of lice infestation among children attending schools before and during the COVID-19 pandemic

3. Discussion

4. Conclusions

5. Material And Methods

5.1 Organization and conduct of the study

5.2 Characteristics of the studied group

5.3 Human head lice infestation verification methods

5.4 Statistical analysis

Declarations

References

Competing Interests

Status:

Version 1