Analysis of optimal control strategies on the fungal Tinea capitis infection fractional order model with cost-effective analysis.

In this study, we have formulated and analyzed the Tinea capitis infection Caputo fractional order model by implementing three time-dependent control measures. In the qualitative analysis part, we investigated the following: by using the well-known Picard-Lindelöf criteria we have proved the model solutions' existence and uniqueness, using the next generation matrix approach we calculated the model basic reproduction number, we computed the model equilibrium points and investigated their stabilities, using the three time-dependent control variables (prevention measure, non-inflammatory infection treatment measure, and inflammatory infection treatment measure) and from the formulated fractional order model we re-formulated the fractional order optimal control problem. The necessary optimality conditions for the Tinea capitis fractional order optimal control problem and the existence of optimal control strategies are derived and presented by using Pontryagin's Maximum Principle. Also, the study carried out the sensitivity and numerical analysis to investigate the most sensitive parameters and to verify the qualitative analysis results. Finally, we performed the cost-effective analysis to investigate the most cost-effective measures from the possible proposed control measures, and from the findings we can suggest that implementing prevention measures only is the most cost-effective control measure that stakeholders should consider.

[Prevention and control of pediatric tinea capitis].

Tinea capitis is a superficial fungal infection of the scalp and hair caused by Dermatophytes. It represents the most prevalent superficial fungal infection among preadolescent children worldwide, including in developing countries such as China. The highly contagious nature of tinea capitis can result in outbreaks within communal settings for children. Furthermore, pustular lesions associated with this condition can lead to permanent scarring and hair loss, imposing a significant psychological burden on affected children and their parents. This article aims to provide a comprehensive literature review encompassing the susceptible person, epidemiological characteristics, trends, etiology, modes of transmission, clinical manifestations, treatment, and prevention strategies of tinea capitis. The ultimate objective is to raise awareness, implement effective prevention and control measures, interrupt the transmission cycle, and ultimately reduce the incidence of tinea capitis in the pediatric population.

Genetic predictors of susceptibility to cutaneous fungal infections: a pilot genome wide association study to refine a candidate gene search.

BACKGROUND: Trichophyton tonsurans is the foremost fungal pathogen of minority children in the U.S. Despite overwhelming infection rates, it does not appear that this fungus infects children in a non-specific manner. OBJECTIVE: This study was designed to identify genes that may predispose or protect a child from T. tonsurans infection. METHODS: Children participating in an earlier longitudinal study wherein infection rates could be reliably determined were eligible for inclusion. DNA from a subset (n=40) of these children at the population extremes underwent whole genome genotyping (WGG). Allele frequencies between cases and controls were examined and significant SNPs were used to develop a candidate gene list for which the remainder of the cohort (n=115) were genotyped. Cumulative infection rate was examined by genotype and the ability of selected genotypes to predict the likelihood of infection explored by multivariable analysis. RESULTS: 23 genes with a putative mechanistic role in cutaneous infection were selected for evaluation. Of these, 21 demonstrated significant differences in infection rate between genotypes. A risk index assigned to genotypes in the 21 genes accounted for over 60% of the variability observed in infection rate (adjusted r(2)=0.665, p<0.001). Among these, 8 appeared to account for the majority of variability that was observed (r(2)=0.603, p<0.001). These included genes involved in: leukocyte activation and migration, extracellular matrix integrity and remodeling, epidermal maintenance and wound repair, and cutaneous permeability. CONCLUSIONS: Applying WGG to individuals at the extremes of phenotype can help to guide the selection of candidate genes in populations of small cohorts where disease etiology is likely polygenic in nature.

The tinea capitis campaign in Serbia in the 1950s.

In this Historical Review we describe the 1950-59 UNICEF-supported campaign to eliminate tinea capitis, also known as ringworm, in Yugoslavia. Medical treatment for this infectious disease involved the use of ionising radiation. We discuss the possible health implications for the treated population. Data were collected from archive documents, newspapers from the 1950s, Yugoslavian scientific reports, interviews with patients who received treatment, and interviews with physicians who gave treatment during the campaign. The campaign screened 878 659 individuals and treated 49 389. On the basis of Israeli tinea capitis research, late health consequences (mainly cancer in the irradiated area) can be expected in the treated Serbian population. The discovery of treatment records for a substantial number of patients makes public-health action and further research possible. The findings are relevant to the Serbian medical community and populations in other countries that used a radiation-based technique for the treatment of tinea capitis.

[Tinea capitis - a recurring problem]. / Tinea capitis - starronový problém.

In the first quarter of the 20th century, tinea capitis represented the most important dermatomycological diagnosis in Europe. For its significant social impacts (affecting children, potential permanent disfiguration), developed countries introduced strict anti-epidemic measures which, together with the discovery of griseofulvin in 1960, contributed to nearly complete eradication of the disease in Central Europe. Since 1980s, however, the incidence of tinea capitis has increased to become a serious medical problem both in America and in some parts of Europe. In the Czech Republic, as well as in the neighbouring countries, the main causative agent remains the zoophilic Microsporum canis. The main agent in the USA, the anthropophilic Trichophyton tonsurans, slowly migrates to the British Isles and Western Europe. Moreover, Trichophyton rubrum is a newly emerging pathogen. Because of different biological behaviour of the individual pathogens, both therapeutic approaches and preventive hygiene measures vary.

Trichophyton mentagrophytes of rabbit origin causing family incidence of kerion: an environmental study.

Our laboratory was contacted by a family living directly above a rabbit farm. Both their children had developed a kerion, in consequence of a misdiagnosed superficial mycosis. This study was designed to demonstrate a link between the two kerion cases and the environmental contamination. The degree of contamination was estimated and factors favourising the spread of infection were determined. Dermatophytes were isolated from various environmental sites using Rodac plates. For direct sampling of scalp and fur the brushing technique was used. The farm and home environment initially showed a severe contamination by Trichophyton mentagrophytes. At the farm, cages and surfaces covered with rabbit hair were strongly contaminated. As for the home environment, the dog's basket and clothes from the mother carried a large number of spores. Trichophyton mentagrophytes was identified as responsible agent for the children's kerions and the lesions of the rabbits. Mother, eldest child and dog seemed to be excellent carriers. Cleaning and disinfection measures resulted in a reduction of the overall contamination. The home environment was no longer a source of contamination. Nevertheless, on the farm a fair number of dermatophytes could still be isolated from the wire meshes and roof beams covered with fluff.

[Survey of Trichophyton tonsurans infection in Japan. Molecular epidemiology and factors affecting adequate hairbrush sampling].

At the 48th Annual Meeting of The Society for Japanese Medical Mycology, held in October, 2004, we reported our findings from a survey on Trichophyton tonsurans infections in the Hokuriku and Kinki regions of Japan. The survey revealed that a few epidemics had occurred across these regions. In this article, we introduce our subsequent studies relating to 1) molecular epidemiology of isolates taken from people in many parts of Japan and 2) factors affecting adequate sampling of the scalp with hairbrushes, essential for surveying and monitoring the infection. In total, 198 isolates of Trichophyton tonsurans were analyzed using restriction fragment length polymorphisms of the non-transcribed spacer regions of ribosomal RNA genes. The restriction enzyme Mva I indicated two molecular types of strains, implying that the causative agents of the epidemic had different origins. None of the isolates obtained from the epidemic showed the same restriction profile as that of isolates from aged and sporadic cases. The published hairbrush method suitable for obtaining samples from the scalp of Judo trainees was reevaluated by changing several factors. We found that sampling should not be done soon after the students' physical training because other fungal elements may give a false positive, samples should not be obtained from students who have recently applied topical antimycotics, and samples should be taken under the guidance of qualified instructors familiar with the sampling method.

[An investigation of Trichophyton tonsurans infection in university students participating in sports clubs].

BACKGROUND: The prevalence of the infectious disease Trichophyton tonsurans is rapidly increasing in Japan, particularly in athletes of these sports such as judo. Recognition of the current prevalence of this disease not only in athletes of these sports but also in other athletes is important to prevent its further spread. SUBJECTS AND METHODS: In November, 2002 we used a questionnaire survey and hairbrush culture to identify hair dermatophyte carriers among 31 members of a university judo club. The dermatophyte carriers received antimycotic therapy, and all participants were taught infection prevention. Repeat screenings of the judo club members were performed 9 times over the following 18-month period. In addition, from November, 2003 to February, 2004 we screened 466 students of other university sports clubs for hair dermatophytes using the questionnaire survey and hairbrush culture technique. RESULTS: (1) Initially, we identified 11 (35%) of 31 members of the judo club as dermatophyte-positive by hairbrush culture. These dermatophyte carriers received antimycotic therapy, and implementation of infection prevention measures by all club members was initiated. Members continued to participate in matches and group judo practices under daily instructions for infection prevention. Tests performed on 9 occasions over a 1.5-year period following the initial testing showed all members of the judo club to be dermatophyte-negative and with no signs of tinea corporis. (2) Using a questionnaire and the hairbrush culture technique, we screened 466 members of other sports clubs, including 138 students who had weekly judo lessons and 185 students who were living in a dormitory. All were dermatophyte-negative by hairbrush culture, and no participant acknowledged any history or presence of eruptions suggestive of tinea. CONCLUSIONS: Our investigation suggests that the current spread of T. tonsurans infection in Japan is occurring mainly in athletes of high-contact sports such as judo. The successful control of this disease by the judo club in our university suggests that spread of the infection can be prevented without requiring that training be discontinued in a group fully informed about the disease.

[How to cope with tinea capitis?]. / Comment gérer les teignes du cuir chevelu?

In Brussels, as in the other European cities with a high rate of immigration, the cases of anthropophilic tinea capitis have risen. Their clinical aspect is more discrete than in zoophilic cases, and you could be easily fooled. This explains why, in 2001-2002, we had some epidemics in schools and creches. Griseofulvin, the gold treatment, was withdrawn from the Belgian market in 1997. The identification of the pathogen when using the new antifungals (fluconazole, itraconazole and terbinafine) is mandatory, dermatophytes showing a different sensitivity to these drugs. The management of an anthropophilic tinea capitis needs some good planning and the cooperation of the family and the school. We describe our procedures in this article.

Tinea corporis, tinea cruris, tinea nigra, and piedra.

Tinea infections are among the most common dermatologic conditions throughout the world. To avoid a misdiagnosis, identification of dermatophyte infections requires both a fungal culture on Sabouraud's agar media, and a light microscopic mycologic examination from skin scrapings. Topical antifungals may be sufficient for treatment of tinea corporis and cruris and tinea nigra, and the shaving of hair infected by piedra may also be beneficial. Systemic therapy, however, may be required when the infected areas are large, macerated with a secondary infection, or in immunocompromised individuals. Preventative measures of tinea infections include practicing good personal hygiene; keeping the skin dry and cool at all times; and avoiding sharing towels, clothing, or hair accessories with infected individuals.

[Tinea capitis from here and elsewhere. Geographic variables in prevention]. / Les teignes du cuir chevelu d'ici et d'ailleurs. Quand la prévention est à géographie variable.

Few diseases exhibit such regional variability in their epidemiology, even in an area as limited as Belgium, as tinea capitis. Thus, anthropophilic tinea capitis is highly predominant in areas where new immigrants from Black Africa and North Africa have settled. By contrast, zoophilic tinea capitis is found largely in areas where the cat population is infected. Kerion often affects professions in which contact with infected livestock is involved. Prevention of tinea capitis thus has distinct regional features. Treatment, on the other hand, has a universal basis.

[Tinea capitis: sample surveys among school doctors and dermatologists in the Paris suburbs]. / Prise en charge des teignes: enquête auprès de médecins scolaires et de dermatologues franciliens.

BACKGROUND: Subsequent to detection of several cases of anthropophilic tinea capitis, we wanted to know whether the legal decree requiring eviction from school and an epidemiology survey in the children community or the family is implemented properly. METHODS: Two sample surveys were carried out among 50 school doctors from the Hauts-de-Seine department and 110 dermatologists working the Paris suburbs. RESULTS: Eviction from school was rare and not based on the type of dermatophytes (anthropophilic or zoophilic agent). Likewise, epidemiology survey was neglected, often being solely clinical for other family members. Systematic sampling in the children community or in the family was very exceptional. DISCUSSION: Despite the rise in the number of cases of anthropophilic tinea capitis in Paris suburbs, the decree is not often implemented. Dermatologists would appear to be responsible for this situation, especially in case of M. langeronii, which is very contagious in nursery school.

[Epidemiology of tinea capitis]. / Epidémiologie des teignes du cuir chevelu.

PREDOMINANT IN CHILDREN: Tinea capitis is the most frequent fungal infection in children under the age of puberty. It occurs only rarely in men but is observed in adult women. Human-to-human, animal-to-human and soil-to-human transmission can be involved. HISTORICAL BACKGROUND: The spectrum of fungal species known to cause tinea capitis has steadily grown for more than a century, varying with the local urban or rural environment. Since the beginning of the 20th century and up to the advent of griseofulvin in the sixties, M. audouinii, an anthropophilic species, caused major epidemics in France, England and the USA. In the sixties to eighties, M. canis was the cause of most cases observed throughout the world. Over the last 20 years, anthropophilic species have again become the leading cause of tinea capitis epidemics, particularly in large cities, in relationship with immigration: T. tonsuransi in the USA and England and T. soudanense and M. langeronii in France. HYGIENE AND EDUCATION: Despite the benign curable nature of the disease, interhuman transmission of tinea capitis is nevertheless a considerable public health problem due to the increasing number of children affected and the risk of contagion in schools. The considerations resulting from recent studies point out the fact that transmission occurs more often in the family than the school setting, particularly indirectly by common use of grooming instruments. This would explain the high percentage of tinea capitis in large immigrant families where hair combing habits favor transmission. In France, these observations should lead to a revision of the current regulations concerning expulsion from school of children affected by tinea capitis. Better education would be a more appropriate response to the problem.

Ringworm of the scalp in primary-school children in Alexandria: infection and carriage.

A total of 510 children from a primary school in Alexandria were examined for tinea capitis, and samples were taken from their scalps. Specimens were examined by direct microscopy and were cultured. Diagnosis was by clinical and mycological findings. Clinical evidence of pediculosis capitis was found in 54.1% of children, more commonly in girls. Dermatophytes were isolated from 7.4% of scalp samples (2.9% confirmed cases, 4.5% carriers). A further 2% were suspected cases as they were negative by mycology. Most of the children were under 10 years and none was aware of having the infection. All isolates were identified as Trichophyton violaceum.