Up to day, only a few studies evaluated the influence of the school environment on the respiratory health of younger schoolage children. At the same time, there is a shortage of studies analyzing the effects of different size range aerosol pollutants. When children enter the first grade of primary school, they are relatively naive to air pollution other than in the home environment. Therefore, children in this age group were chosen as the target group. Our study aimed to evaluate indoor air pollution particle number and mass concentrations in primary schools and the impact of different size range particles on asthma morbidity among younger school-age children.

Objectives: In July 2018, vaccine against meningococcal B infection in Lithuania was added to the national vaccination calendar. However, vaccination rates were low. The aim of the study was to identify parents' attitudes towards meningococcal disease and vaccination.Methods: In the period from February to March 2019, a questionnaire survey was conducted; 483 parents of children aged up to 2 years participated. In the validated questionnaire respondents provided data on their gender, education, age and answered questions that helped to estimate knowledge and attitudes towards meningococcal disease and vaccination.Results: Parents with higher education are more likely to believe that meningococcal infection can be prevented; 316 (65.4%) parents are concerned that their child is at high risk of infection and evaluated the level of anxiety M = 7.39, SD = 2.29 out of 10 points; 309 (64.0%) believe that the vaccine is effective (M = 8.41; SD = 1.15 out of 10 points). One third of parents will not vaccinate their children because they believe that the MenB vaccine is not safe (71.2%); 370 (76.6%) have heard negative information about this vaccine, the majority (83.2%) from the Internet. The negative information received is positively correlated with the belief that the vaccine is not effective (r = 0.18, p = 0.031) and not safe (r = 0.35, p < 0.001); 49.3% of parents report side effects after vaccination; 326 (67.5%) parents believe that they need more evidence-based information on MenB vaccination and 90.8% would like to get it from a healthcare professional.Conclusions: Due to high level of mistrust of vaccines and the lack of evidence-based information, parents decide not to vaccinate their children against meningococcal B infection. There is a great need for parents' education and the dissemination of evidence-based information among them.

The school environment is crucial for the child’s health and wellbeing. On the other hand, the data about the role of school’s aerosol pollution on the etiology of chronic non-communicable diseases remain scarce.Objectives: To evaluate the level of indoor aerosol pollution in primary schools and its relation to the incidence of doctor’s diagnosed asthma among younger school-age children.Methods: The cross-sectional study was carried out in 11 primary schools of Vilnius during one year of education from autumn 2017 to spring 2018. Particle number (PNC) and mass (PMC) concentrations in the size range of 0.3-10 µm were measured using an Optical Particle Sizer (OPS, TSI model 3330). The annual incidence of doctor’s diagnosed asthma in each school was calculated retrospectively from the data of medical records.Results: The total number of 6-11 years old children participated in the study was 3638. The incidence of asthma per school ranged from 1.8 to 6.0%. Mean indoor air pollution based on measurements in classrooms during the lessons was calculated for each school. Levels of PNC and PMC in schools ranged between 33.0-168.0 part/cm 3 and 1.7-6.8 µg/m 3 , respectively. There was a statistically significant correlation between the incidence of asthma and PNC as well as asthma and PMC in the particle size range of 0.3-1 µm (r=0.66, p=0.028) and (r=0.71, p=0.017) respectively. No significant correlation was found between asthma incidence and indoor air pollution in the particle size range of 0.3-2.5 and 0.3-10 µm.Conclusions: We concluded that the number and mass concentrations of indoor air aerosol pollution in primary schools in the particle size range of 0.3-1 μm are primarily associated with the incidence of doctor’s diagnosed asthma among younger school age-children.