Pediculosis capitis among Primary School Children and Related Risk Factors in Urmia, the Main City of West Azarbaijan, Iran

Abstract Background: Pediculosis capitis is cosmopolitan health problem. In addition to its physical problems, its psychological effects especially on pupils are more important. This study was conducted to determine the Pediculosis capitis among primary school pupils and also find out the role of probable related risk factors in Urmia city, Iran 2010. Methods: 35 primary schools of Urmia City according to the defined clusters randomly have been selected during 2010. 2040 pupils (866 boys and 1174 girls) were included and examined individually and privately by experts. Presence of adult or immature lice or having nits less than 1 cm from the hair basis were defined as positive. Data about demographic features and factors which their effect should be determined were recorded in standard questionnaire. Data were analyzed by SPSS software with proper statistical test. Results: Infestation was determined around 4%. Girls show significantly greater infestation. The availability of suitable warm water for bathing and hair length (separately in girls and boys) are significantly related to infestation load as well as infestation among different age groups. There was no significant relation between parent's education and job and infestation as well as bathing repetition per week and the kind of energy source which they have. Also there is no significant correlation between educational grades and head lice infestation. Conclusion: The head louse pediculosis is a health problem and remains a health threatening for school children.Effective risk factors should be determined carefully and regionally. Proper training plays a great role in order to prevent and control the problem

Isolation, identification and biotyping of virulent Yersinia enterocolitica from pasteurized milk

In order to investigate the presence of virulent Yersinia enterocolitica in pasteurized milk, 242 samples were collected from Tabriz retails from 2011 to 2012. The samples were enriched in PSBB. Afterwards, virF and ail genes were exploited as target sequences for the detection of virulent Y. enterocolitica. PCR-positive samples were cultured on CIN agar and MacConkey agar. The selected isolates were confirmed by second-phase duplex PCR. For the biotyping of Y. enterocolitica, certain biochemical tests were performed on the isolate. The pasteurized milk samples were further analyzed for the enumeration of hygiene indicator bacteria and qualitative alkaline phosphatase (ALP) test. Virulent Y. enterocolitica were detected in 6.61% (16/242) of samples by ail-PCR, however, using virF-PCR 4.13% (10/242) of the samples were identified as positive. Among PCR-positive samples only 0.41% (1/242) were isolated by culture method and confirmed by second-phase duplex-PCR. Based on the biochemical assays, the isolated Y. enterocolitica was identified as biotype 4. Furthermore, 11.57% (28/242) of the samples were found positive for alkaline phosphatase test. The results revealed that the number of hygiene indicator bacteria in ALP-positive samples was significantly (

Diversity of Bacillus species isolated from biofilm of raw milk tankers and dairy processing equipments

Bacillus is the dominant genus encloses gram-positive spore-formers that some are considered as a threat to the quality of foods and consumers’ health. This study aimed to explore the occurrence of Bacillus species in raw milk tankers and dairy processing equipments as well as to examine the biofilm-forming ability of the isolates. For this reason, a total of 80 samples consisting of 30 samples obtained from raw milk tankers, 30 samples of dairy processing equipments and 20 samples from various surfaces of the production plant was collected. According to the results, 16.66% of the samples obtained from raw milk tankers, 20% of dairy processing equipments and 40% of surface samples were found positive for Bacillus species. Various species of the Bacillus were found; amongst B. cereus with 36% and B. aloe and B. pumilus with 4% occurrence rate, were the most and least abundant species, respectively. Results of biofilm production revealed that 96% of the isolates were capable of producing biofilm. Eventually, it was concluded that conventional CIP procedure is unable to entirely remove the biofilm of Bacillus species from dairy plant surfaces. Hence, there is a need for a new approach to conquer the problem

Contamination rate, antibiotic susceptibility profile, biofilm formation and presence of TSST-1 gene in Staphylococcus aureus isolates

This study aimed to investigate the prevalence of Staphylococcus aureus in raw milk and traditional dairy products of West-Azerbaijan Province and also to evaluate the presence of TSST-1 virulence gene, antibiotic resistance and biofilm formation of the isolates. Using stratified random method, a total of 80 raw milk and traditional dairy products (including traditional cheese, cream and curd) together with 20 nasal swab samples of the dairy products’ manufacturers were collected. S. aureus strains were isolated and identified by conventional culture methods. Afterwards, the isolates were subjected to PCR analysis to detect the presence of TSST-1 gene. According to the findings, 35% of the samples were contaminated by S. aureus. Moreover TSST-1 gene was recognized in 1 cheese and 2 swab samples. Antibiotic resistance profile revealed that most of S. aureus isolates were resistant towards vancomycin, penicillin, and methicillin and sensitive towards co-trimoxazole, gentamicin, rifampin, oxacillin, and cephalothin. Moreover, 2.85%, 17.15%, and 80% of the isolates were capable to form high, moderate and low amounts of biofilm. High occurrence of S. aureus in milk and dairy products which harbor TSST-1 virulence gene, and the strains that demonstrated resistant to several antibiotics and capable of biofilm formation, could be considered a health threat to the consumers of these products

Molds contamination of raw milk and dairy products: Occurrence, diversity and contamination source

This study aimed to assess the occurrence and diversity of mold species in raw milk and its products along with the identification of potential contamination sources. For this reason, a total of 260 samples consisting of 80 raw milk, 100 dairy products (i.e., pasteurized milk, yoghurt, cheese and buttermilk) and 80 environmental (i.e. ingredients, packaging materials, surface of processing equipments and air) specimens were collected. Using culture assay and microscopic observation, the occurrence as well as the diversity of mold species was investigated. According to the results, 82.3% of the samples were identified as positive for mold contamination. The percentage of mold contamination for raw milk was estimated as 97.5%. In the case of pasteurized milk, yoghurt, buttermilk, cheese and environmental samples, it was determined as 52%, 76%, 52%, 56% and 96.25%, respectively. Mold diversity among various samples consisted of Aspergillus, Geotrichum, Penicillium, Mucor, Alternaria, Rhizopus, Stemphylium, Cladosporium, and Fusarium. Results revealed a significant (p < 0.01) correlation between kind of mold species isolated from raw milk and dairy products. Similarly, a correlation was observed between dairy products and environmental sources. Regarding the high occurrence of mold contamination in raw milk and environmental sources, it seems that in some instances heat treatment was not effective enough to inactivate all molds; whereas in some other cases, cross contamination may have resulted in mold contamination. Therefore, it is crucial to maintain hygienic conditions during raw milk handling as well as processing steps. These practices could efficiently reduce the occurrence of mold contaminations in dairy products

Behavior of various strains of Yersinia enterocolitica in Ultra-filtered cheese and inhibitory effect of lactic starter bacteria

This study aimed to assess the behavior of various strains of Yersinia enterocolitica in ultra-filtered (UF) cheese and to evaluate the inhibitory effect of lactic starter bacteria on survival of Y. enterocolitica. To this end, pasteurized ultra-filtered milk was inoculated with 3 log cfu/g of two standard strains (DSM 11502 and DSM 9499) and one native strain of Y. enterocolitica. UF cheese samples were produced with and without starter culture. Enumeration of Y. enterocolitica was performed at the time of inoculation, after incubation time and during the 2-months storage period on CIN agar. The enumerated colonies were confirmed by PCR. Results revealed that after incubation, the populations of Y. enterocolitica in both groups increased by 4.14 log cfu/g (P < 0.01). However, during the storage period the number of Y. enterocolitica decreased only in the samples made with starter cultures. pH values revealed a significant difference (P < 0.01) between the samples made with and without starter culture; therefore, it seems that acidic pH is the major factor inhibiting the survival of Y. enterocolitica in UF cheese. Besides, a significantly (P < 0.01) different behavior was observed among native and standard strains. Considering the inhibitory effect of starter bacteria,it seems that creation of proper conditions in terms of temperature and the time necessary for proliferation and activity of starter bacteria or application of cultures capable of producing antagonistic products can be effective in controlling possible microbial contaminations along with the development of desirable aroma and texture in UF cheese

Effect of ozone treatment on quality features and microbial load of sumac, cumin and pepper spices

Herbs are often produced by traditional methods and in poor sanitary conditions and can contain high amounts of spoilage and pathogenic microbes. The aim of this study has investigated the effect of ozone on some qualitative characteristics and microbial spices sumac, cumin and pepper. For this purpose, samples were treated by ozone at a concentration of 2 g per hour for 10, 20, 40 and 60 minutes. Then microbial count and chemical characters such as moisture content, antioxidant properties, and phenolic compounds were determined. The results showed that compared with controls, treatment with ozone decreased 2 logarithmic units (

Effect of attenuated lactobacillus plantarum as adjunct starter on lipolysis and organoleptic characteristics of UF white cheese

The main objective of this study was to determine the effect of attenuated adjunct culture of lactobacillus plantarum on the lipolysis of UF-white cheese as measured by acid degree value, the fatty acids profile, physicochemical, microbial and sensory characteristics during ripening. The results showed that, treated UF cheeses exhibited no significant (p>0.05) differences in chemical composition (dry matter, fat, salt and pH) in comparison with the control UF cheeses throughout 60 days of ripening. Total bacterial count and mesophilic lactobacillus count in the UF cheeses using attenuated adjunct starter were significantly (