Journal of Occupational

  Background: Head lice infestation is one of the most common parasitic infections with a long history in the world . The purpose of this study was to determine the prevalence of head lice infestation among 3-6 years old children going to nursery schools in Kashan, Iran in 2009.

  Materials and Methods: This cross-sectional study was performed on 1200 children having the age range of 3-6 years old in February 2009. The infestation was confirmed by the presence of nit, nymph and adult species in the children's hair. The causing agent, Pediculus Capitis, was isolated by combing for 3-5 minutes or using manual lens. Then a questionnaire was completed and the data were categorized and compared using Fisher^'s exact test.

  Results: The results demonstrated that 8 children, (0.7%, out of 1200) were infected with the parasite. The prevalence rates of infestation among girls and boys were 1.14% and 0.17%, respectively. Infestation prevalence rates were 8.3% and 0.43% among children having unemployed and employed fathers respectively (P<0.001). About 2% of children who were living in family with five or more members were infected which was significantly higher than its proportion (0.4%) among children living in families with 3-4 member (P<0.031).

Conclusions: The prevalence rate of head lice infestation was higher among children living in big families and also among children who had unemployed fathers. Appropriate parental education, weekly inspection of the nurseries in order to find the infected children and referring them to health centers, can decrease the incidence rate of head lice infestation.

  Background: It has been prover that the prevalence of experiencing job related stress is very high among the dentists. This stress can be the result of factors such as poor lightening of dental office and noise. This stress can cause emotional distress and threaten dentists’ physical health and affect the quality of their life. This study is conducted to determine dentists’ professional quality of life and job-related stress and two important workplace factors that can affect them which are lighting and noise.

  Materials and Methods: In this cross-sectional study the researchers visited the dental offices in Shiraz city and measured lighting and noise of the places, also dentist's quality of life and job stress were determined using McGill quality of life questionnaire and job-stress questionnaire.

  Results: The relationship between quantitative variables was determined by using regression test and the multiple regression test was used for the modeling process. The average of local noise caused by dental drills and other parameters was 75.5 and 74.5 in public and private offices. In 2.2% of dental offices lightening condition was below the standard levels. Results show that 58.9% of dentists participating in this study experience good or fairly good quality of life.

  Conclusion: The results suggest that workplace environmental situation and dentists’ professional stress and quality of life are correlated. So adjusting effective workplace parameters to the standard levels can lead to increase in the dentists’ quality of life.

  Background: Approximately, 90% of workplace accidents are due to human errors. The study of the relationship between individual differences and accidents and injuries are beneficial in the prevention of these accidents. The aim of the present study was to examine the relationship between extraversion, agreeableness, conscientiousness, and neuroticism and occupational accident rates in the petrochemical industry.

  Materials and Methods : This was a descriptive correlational study. The study population consisted of line employees of Khorasan Petrochemical Company in Bojnourd, Iran (n = 1160) 300 employees were selected using stratified random sampling. Data collection tools consisted of the NEO Five-Factor Inventory and Incident Reporting Rate Scale. In order to analyze the data, regression analysis and to validate the results, confirmatory factor analysis were performed using AMOS 21 software.

  Results: Findings indicate that correlation coefficients between the five-factor personality traits and occupational accident rates were significant (P < 0.001). In stepwise multiple regression analyses, of the 5 independent variables, only the 2 variables of conscientiousness and agreeableness found permit entry into the regression equation (R² = 0.186, P < 0.001).

  Conclusions: The results of this study showed the importance of conscientiousness and agreeableness as predictors of occupational accident rates. Therefore, in order to select people for working in high risk environments, such as the petrochemical industry, we should rely on these variables.

Background: Health-promoting lifestyle is one of the determination criteria for health factors and the prevention of health-threatening factors. According to the available statistics, 53% of deaths are related to lifestyle. The aim of this study was to evaluate health-promoting lifestyles in medical students of Rafsanjan University of Medical Sciences (RUMS), Rafsanjan, Iran.

Materials and Methods: This was a descriptive study conducted in 2014 on 262 volunteer medical students. To collect data, a demographic information questionnaire and the Health-Promoting Lifestyle Profile II (HPLP-II) were used. Minimum and maximum scores of HPLP-II were 48 and 192, respectively. Data analysis was conducted using t-test, one-way ANOVA, Tukey's multiple comparison test, and non-parametric Kruskal-Wallis test.

Results: In this study, 58.8% of the participants were women. The mean age of the participants was 22.50 ± 2.16 years. The mean and standard deviation of the HPLP-II score of the medical students was 109.74 ± 18.65. There was a significant relationship between health-promoting lifestyle and variables of age (P = 0.007), university entrance year (P < 0.001), mother’s education level (P = 0.003), and father’s education level (P = 0.011). However, no relationship was observed between health-promoting lifestyle and parental occupation and place of residence (P > 0.050).

Conclusions: This study showed that the status of health-promoting lifestyles in medical students of RUMS was at a moderate level, but it is still at a great distance to the optimal level. Therefore, it is necessary to implement programs to promote a healthy lifestyle in order to maintain health in the youth until graduatio.

Background: Vibration as one of the harmful physical factors is relatively present in a wide range of jobs. Musculoskeletal disorders (MSDs) are among the most prevailing complaints of workers encountering occupational factors for example vibration. Therefore, this study was conducted to investigate vibration and its association with the MSDs in upper limbs of heavy mine vehicles drivers.

Materials and Methods: This cross-sectional study was conducted, on heavy mine vehicles of Gol-Gohar Sirjan Centre, Sirjan, Iran. In general, 288 drivers with 92 vehicles were working at the mine site. SVAN958 vibration meters and the Nordic Musculoskeletal Questionnaire were used to measure whole body vibration and upper limb MSDs, respectively. Finally, the data were analysed using SPSS.

Results: The highest average equilibrated acceleration was in graders (2.179 m/s²) and drills had the lowest average acceleration (0.479 m/s²). Prevalence of MSDs within past 12 months showed a significant difference in the neck (P = 0.044) and elbow (P = 0.023) between case and control group. The whole body vibration variable was associated with MSDs in the neck (P = 0.020) and wrist/hands (P = 0.030), and with increase in vibration the MSDs showed a 59% increase in neck and 72% in wrist/hands. In multivariate analysis, the whole body vibration variable had a significant relation with MSDs in wrist/hand (P = 0.027) and caused an 83% increase in the risk of MSDs per each unit in wrist/hand.

Conclusions: The prevalence of disorders in studies with short duration is probably not quite visible; however, by increasing the working experience with these vehicles which have higher vibration than standard rates, the chance of developing MSDs increases.

Background: The spread of the novel coronavirus seems mysterious enough to make us double-check the indices being used to predict its transmission. In this study, serological analysis was performed to assess some metric and epidemiological aspects of the infection and its transmissibility among people in contact with SARA-CoV-2 patients.   
Material and Methods: A total of 453 contacts of 40 COVID-19 patients entered this contact tracing prospective cohort study. Accordingly, SARS-CoV-2 patients were diagnosed by the real-time polymerase chain reaction testing of nasopharyngeal samples. The infectiousness history was detected by the serological testing of IgG and IgM. Trained expert team completed two questionnaires, and blood samples were taken by experts in a laboratory. Data were analyzed using SPSS V21.0 and R software.
Results: The mean ages of the SARS-CoV-2 patients and the contacts were 53.0±18.2 and 30.8±19.3 years, respectively. The overall R₀ of the infection was 2.58. Household and non-household secondary attack rates (SAR) were 20% (95%CI; 12.7–27.3) and 11.3% (95%CI; 6.1-16.5), respectively. The transmission probability of each contact was 0.0205, and the serial interval was 6.4±4.6 (95% CI; 5.2–7.6) days. The SAR was higher among the contacts who were exposed to asymptomatic primary cases (28%, 95%CI; 10-46%) than (13.8%, 95%CI; 9.4-18.2) among those exposed to symptomatic patients. 
Conclusions: It is concluded that the herd immunity of 60 to 65% is needed in human communities, based on the amount of R₀ estimated in our survey. The findings demonstrated the amount of the reduction in infection R₀, which is predicted based on both clinical and public health interventions.