A school environment may cause positive effect upon health and healthy behavior, but also representmain factor for transfer of non-infectious diseases. Therefore, the issue of maintaining an appropriate environment in operations of training and educational institution would be considered as vital in every country of the world. In our country the solid waste hygienic conditions around children organizations represent one of actual problems. Through the research work was aimed to evaluate the state of solid waste at external environment of general educational institutions by the momentum model of analytical research and involving 103 state proprietary Educational Institutions of 9 districts. At developing estimation list of solid waste at external environment of schools were used current effective standards, resolutions and regulations. 88.3 percent of schools involved into research work had special solid waste-points and 11.7 percent had no special solid waste-points. 38.8 percent of solid waste-points were fenced from all sidesand 44.7 percent fenced from some sides and 16.5 percent had no fence in whole. The research of material from which was made a solid waste-keeping facility showed that 44.2 percent were made from metal, 2.3 percent from wood and 52.3 percent from brick. When we studied whether the solid waste-keeping facility is placed in distance of 25 meters from school according to standard,was determined that 71.8 percent were built according to the standard, 28.2 percent were allocated within 25 meters showing inconformity with the standard. During the research it has been detected that among schools 27.2 percent had too much solid waste-heap, 25.5 percent had placed no special recycle-bins on the school site and 13.6 percent conducted wrong activity by incinerating solid waste on the territory of school.2/3 or total 63 schools among Metropolitan state proprietary educational institutions has non- standard solid waste-keeping facility, 1/3 or 29 schools has located their solid waste-points in non- standard distance, there exists much solid waste-heap because of insufficient recycle-bins, absence of solid waste-points results in collection of solid waste in a special room inside of school and later its transportation with scavenger. Also, 13.6 percent or 14 schools are incinerating their solid waste within school site. This breeches effective hygienic norms and normative.

Objectives: Infections with hepatitis B, C, and D virus (HBV, HCV, and HDV) are a major public health problem and lead to serious complications such as cirrhosis and hepatocellular carcinoma. We aimed to determine the seroprevalence of hepatitis B surface antigen (HBsAg), anti-HCV, anti-HDV immunoglobulin G, alpha-fetoprotein (AFP), and dual and triple hepatitis virus infections in Mongolia. Methods: A total of 2313 participants from urban and rural regions were randomly recruited for this cross-sectional study. A questionnaire was used to identify the risk factors for hepatitis virus infections, and the seromarkers were measured using immunoassay kits. Results: Among all participants, the prevalence of HBV, HCV, and HDV was 15.6%, 36.6%, and 14.3%, respectively. The infection rates were significantly higher in females and participants with a lower education level, rural residence, older age, and a history of blood transfusion. HBV and HCV co-infection was found in 120 (5.2%) participants and HBV, HCV, and HDV triple infection was detected in 67 (2.9%) participants. The prevalence of elevated AFP was 2.7%, 5.5%, and 2.6% higher in participants who were seropositive for HBsAg (p=0.01), anti-HCV (p<0.001), and anti-HDV (p=0.022), respectively. Elevated AFP was more prevalent in participants co-infected with HBV and HCV (5.8%, p=0.023), HBV and HDV (6.0%, p<0.001), and triple-infected with HBV, HCV, and HDV (7.5%) than in uninfected individuals. Conclusions Nearly half (49.8%) of the study population aged ≥40 years were infected with HBV, HCV, or HDV, and 22.4% had dual or triple infections.