Hair and scalp mycobiota in school children in Nablus area

Hair and scalp mycobiota of 1389 clinically normal children aged 6–12 years attending 12 schools in the Nablus District, Palestinian Authority, was assessed on three occasions over 8-month period (October 1998–May 1999) using the hair brush technique. One hundred and one fungal species belonging to 33 genera were recovered: 6 dermatophytes, 16 dermatophyte-like keratinophilic fungi, and 79 other keratinophilic fungal species. Species varied considerably in their frequency of occurrence and abundance based on their relative importance values (RIVs). The most frequent and abundant species were: Cladosporium cladosporioides, Cl. herbarum, Penicillium chrysogenum and Aspergillus flavus. Microsporum canis, Aphanoascus fulvescence and Chrysosporum sulfureum were the most frequent and abundant species of all dermatophytes and dermatophyte-like keratinophilic fungi recovered. The most frequent and abundant dermatophytes in different communities were M. canis in rural (RIV 0.87) and urban children (0.45), and Trichophyton violaceum (1.41) in refugee camp children. Chrysosporium species were the most frequent and abundant dermatophyte-like keratinophilic fungus in children from all localities followed by Aphanoascus fulvescence. Comparable results on the frequency and abundance of human hair and scalp mycobiota component fungi were obtained based on age group and sex of children. Higher number of species was recovered in spring months (73 species) than in autumn (57) and winter (44) months. Similar occurrence pattern was also noted for dermatophyte-like keratinophilic species and dermatophytes. Higher percentages of children with moderate (11–50) and heavy (≤ 50) spore loads (7.54 and 0.73, respectively) were found in urban school children community than in rural and refugee camp school children (4.7 and 0.1, respectively). Also significantly higher light (1–10) spore load percentages were found in rural (63.67) and refugee camp (62.9) than in urban children (52.6). Of all localities, school children with light spore load comprised the highest percentage of the children examined (37.4), followed by moderate (6.13), and heavy (0.41) spore load categories. However, children with undetected spore load comprised 36.05% of all children. Spore load distribution did not show clear seasonal variations in the study period. Higher percentages of moderate and heavy spore loads were found in male children (8.72 and 0.69, respectively) than in female children (3.4 and 0.1, respectively). However, higher percentages of undetected (38.3) or light spore loads (58.4) were found in females than in males (34.04 and 56.53, respectively). This revised version was published online in June 2006 with corrections to the Cover Date.     

Ecology of cycloheximide-resistant fungi in field soils receiving raw city wastewater or normal irrigation water

The effect of raw city wastewater irrigation on biodiversity and population densities of a cycloheximide-resistant (CH) fungal community was studied in 13 field soils receiving either raw city wastewater or normal irrigation, and in raw city wastewater in the Nablus area, using the hair baiting technique (HBT) and a surface soil dilution plating (SSDP) technique. Three of these fields [one had been receiving raw city wastewater for more than ten years and was designated a heavily polluted field, and the other 2 were cultivated for the first time and were either irrigated with raw city wastewater (newly polluted field) or normal irrigation water (nonpolluted)], were sampled 4–7 times over a 9-month period. The other ten fields, which had been under raw city wastewater irrigation for more than 10 years, were sampled only once. Fifty-seven CH-resistant species belonging to 18 genera were recovered, of which 49 species were recovered from soil habitats and 28 species from raw city wastewater. The HBT had shown to be more efficient in the isolation of pathogenic and potentially pathogenic fungi including dermatophytes. A higher percentage of this group of fungi was recovered from the three main field soils studied using HBT (70% of all isolates), than the SSDP (35.5%); no dermatophytes were recovered by the SSDP method. Two dermatophytes (Microsporum gypseum, and Trichophyton ajelloi), and five more fungi (Arthroderma cuniculi, A. curreyi, Chrysosporium keratinophilum, C. tropicum, and C. pannorum), were recovered from these habitats. Wastewater irrigation seemed to have affected the fungal population densities, with the highest population densities being found in the heavily polluted field soil, while lower population densities were found in the nonpolluted field soil. Increases in organic matter were also observed as a result of sewage effluent irrigation. However, basic similarities in the biodiversity of CH-resistant fungal communities existed in nonpolluted and polluted field soils, and raw city wastewater. Comparable numbers of fungal species were recovered from the three main field soils. The species most commonly found in those habitats included: Alternaria alternata, Aspergillus candidus, Geotrichum candidum, and Paecilomyces lilacinus. Field soils receiving either raw city wastewater or normal irrigation water, were found to be rich in pathogenic and potentially pathogenic CH-resistant fungi, including dermatophytes, with raw city wastewater yielding the highest percentage (81%), followed by the newly wastewater irrigated field (77.7%), the nonpolluted field (67%), and the heavily polluted field (63.4%). Hygienic measures should therefore be taken to control the spread of these fungi in the environment of human communities, and to avoid mycotic infections among farmers. This revised version was published online in August 2006 with corrections to the Cover Date.