Background: The first confirmed case of COVID-19 in Mongolia was reported on November 11, 2020. In response, the government imposed a nationwide lockdown, which significantly impacted the population’s mental health. Heightened levels of stress, anxiety, loneliness, and depression during the pandemic altered individuals’ psychological stability and behavior. Personality traits—defined as relatively stable patterns of emotion, cognition, and behavior—play a key role in stress responses and emotional regulation under pressure. Emerging evidence suggests that these psychological factors may influence the immune system’s responsiveness, including vaccine-induced antibody production. Aim: To evaluate the association between post-vaccination antibody responses and personality types following two doses of COVID-19 vaccines. Materials and Methods: A total of 738 participants who received two doses of COVID-19 vaccines (AstraZeneca ChAdOx1, n=29; Pfizer-BioNTech, n=119; Sinopharm BBIBP, n=590) and had no prior SARS-CoV-2 infection were enrolled. Serum samples were collected 21–28 days after the second dose, and SARS-CoV-2 RBD (S) IgG antibodies were measured using ELISA (Proteintech Inc., USA). Personality types were assessed using a 56-item temperament questionnaire developed by A. Belov, categorizing individuals into classical temperament types (choleric, phlegmatic, sanguine, melancholic). Logistic regression and ROC analysis were used to examine associations between personality types and antibody response. Results: The presence of an antibody response was significantly higher among individuals with a melancholic temperament, and significantly lower among those with a phlegmatic temperament. Furthermore, antibody titers were higher in participants with melancholic and sanguine temperaments and lower in those with a phlegmatic type. Conclusions 1. During the early period following the second dose of COVID-19 vaccination, the antibody response was higher in individuals with a pure melancholic temperament, while it was lower in those with a phlegmatic temperament. 2. After the second dose of the Sinopharm BBIBP COVID-19 vaccine, antibody titers were higher in individuals with pure melancholic and sanguine temperaments, and lower in those with a phlegmatic temperament.

Background: The first case of COVID-19 was reported in our country on November 11, 2020. As of 2023, a total of 869,385 cases and 2,128 deaths have been recorded nationwide. The World Health Organization (WHO) has recommended that countries use 15 vaccines from 11 manufacturers listed for emergency use. The WHO has advised low-income member states to prioritize vaccinating healthcare workers and other high-risk populations vulnerable to severe illness and death from COVID-19. The main goal of the coronavirus vaccination program is to prevent infection, complications, and death among priority target groups, such as healthcare workers and other populations at high risk of severe illness. The effectiveness of the vaccination is measured by its ability to reduce the risk of illness, hospitalization, and death from COVID-19-related complications among vaccinated individuals. While extensive research is being conducted globally to develop, evaluate, and assess the effectiveness and outcomes of COVID-19 vaccines, there has been limited research focused on these outcomes within our country. This gap highlights the need for and serves as the basis of the present study. Аim: To assess the risk of infection, hospitalization, and associated risk factors among healthcare workers vaccinated against COVID-19, and to examine the factors that influence these risks. Materials and Methods: A This follow-up study was conducted over an 80-week period—at weeks 12, 24, and 48—from February 23, 2021, to December 31, 2022. The study involved healthcare workers from Ulaanbaatar city and the aimags of Bayankhongor, Orkhon, Bulgan, Dundgovi, Darkhan-Uul, and Dornod. The study was conducted over a period of 1.5 years (80 weeks) following the administration of the first two doses of the COVID-19 vaccine. Data were collected from participants at three time points: before vaccination, after the second dose, and after each booster dose. A structured questionnaire comprising 7 sections and 49 questions was used for data collection, and the results were analyzed using SPSS version 26.0. Results: Of the total respondents, 574 (60%) worked in direct contact with infected individuals in the 'red zone,' while 370 (40%) worked in the 'yellow zone.' Additionally, 250 participants (27.1%) were healthcare workers from Ulaanbaatar city, and 674 (72.9%) were from rural areas. In our observational study, the risk of new infections among healthcare workers increased over time, rising from 38.4% at week 24 to 59.6% by week 80. Hospitalizations also increased during the follow-up period: 24 cases (2.6%) were recorded at week 12, 160 (17.3%) at week 24, 202 (21.9%) at week 48, and 204 (22.1%) by week 80. Among frontline workers in rural areas, those in Bayankhongor and Orkhon aimags exhibited a lower risk of infection compared to their counterparts in other aimags. Conclusion In our follow up study, an increase in the duration since primary immunization was associated with a higher risk of new infection among workers, rising from 38.4% at 24 weeks to 59.6% at 80 weeks post-vaccination. Administration of additional (booster) immunizations was associated with a reduced risk of subsequent infection. COVID-19 vaccination was associated with a reduced risk of complications necessitating hospitalization. Employment in rural settings and designated red zones was identified as a risk factor for incident infections, hospitalizations, and reinfections.

Background: A 2018 study on the global burden of disease, accidents, and risk factors reported that 1.6 million peo ple died in 2017 due to household air pollution. Poor indoor air quality has been highlighted as a contributing factor to respiratory diseases, cardiovascular conditions, and exacerbation of asthma and allergies. A 2019 study estimated that long-term exposure to fine particulate matter (PM2.5) with a diameter of 2.5 micrometers or less reduces average life expectancy by 1.8 years, with more severe effects in highly polluted regions. Additionally, a study by Miller et al. (2007) found that prolonged exposure to PM2.5 increases the risk of cardiovascular diseases, particularly among women. Direct measurement devices are highly effective in determining indoor PM2.5 concentrations, identifying sources of pollution, tracking pollutant dispersion, and monitoring temporal variations. Studies suggest that direct measurement is an accurate, cost-effective method that provides detailed data suitable for local conditions. Aim: To investigate the indoor air quality of houses and apartments in Darkhan city during the winter season using the Purple Air monitoring device. Materials and Methods: A cross-sectional study was conducted with a targeted sample of 128 households in Darkhan city. The study examined factors such as stove type, type of coal used, annual and daily coal consumption, frequency of heating, and chimney sealing conditions. To collect data, the Purple Air monitoring device was installed in each house hold for a month, after which it was retrieved. During retrieval, participants completed a questionnaire. The questionnaire consisted of 55 questions across 7 pages at the time of device installation and 25 questions across 3 pages at the time of device retrieval. The collected data was analyzed using SPSS 25.0. Results: A total of 128 households in Darkhan city participated in the study. The average duration of residence in the current home was 9.5 years, with no statistically significant variation. The distribution of housing types was as follows: traditional Mongolian gers (40.6%), houses (39.1%), and apartments (20.3%). The 24-hour average PM2.5 concentration was highest in gers (70.9 μg/m³), followed by houses (46.8 μg/m³) and apartments (22.8 μg/m³), with a statistically significant difference (p=0.0001). PM2.5 levels were most variable in gers, followed by houses and then apartments. House holds using central heating (apartments) had an average 24-hour PM2.5 concentration of 22.8 μg/m³, whereas households using stoves (gers and houses) had a significantly higher concentration of 59.4 μg/m³ (p=0.0001). However, there was no statistically significant difference between traditional and improved stoves. Among study participants, 21.4% reported that someone in their household smoked indoors. Additionally, 86.5% regularly burned incense, candles, or herbs, while 99.2% did not use an air purifier. Conclusion The indoor particulate matter concentration in houses and gers in Darkhan was 59.4μг/m3. Variations in stove types, poor chimney sealing limited space, and frequent gaps and cracks contribute to increased spread of indoor air pollutants.

Background: Hepatitis virus infections are widespread and highly endemic in Mongolia and ranks first in the world for liver cancer mortality per 100,000 population, eight times the world average. The World Health Organization estimates that more than 2 billion people are infected with the hepatitis B virus. Each year, 1 million people die from the infection, 4 million are newly infected, and approximately 350-400 million are chronic carriers. In 2018, 475 cases of viral hepatitis were recorded nationwide, accounting for 1.1 percent of all communicable diseases, a decrease of 59 cases or 0.2 per 10,000 population compared to the previous year. In 2016, 194 WHO member countries joined forces to develop a strategy to reduce viral hepatitis, with the goal of reducing mortality by 65% and new infections by 90% by 2030. In order to achieve this goal, the strategic goal states that each country must conduct a comprehensive public health study and intervention on the spread of infection, risk factors, and early detection. Aim: Study to the coverage of hepatitis B immunization among children aged 0-9 years in urban and rural Mongolia and to determine the influencing factors. Materials and Methods: A Nationwide population based cross-sectional study design was used in this study. Mongolia is geographically divided into the western, Khangai, eastern, and central regions. A total of 14 provinces were selected randomly in addition to Ulaanbaatar city. The appropriate sample size was estimated at 4500 children aged 0-9 years, based on 2019 demographic data from the National Statistics Office. The questionnaire contained closed and semi-closed questions on demographics, socio-economic status, vaccination history and etc. Results: A total of 5027 children aged 0-9 years were enrolled in this study out of which 33.7% (n=1692) and 66.3% (n=3335) were enrolled from capital city Ulaanbaatar and provinces, respectively. Almost half (n=2552) of the study participants were boys whereas the remaining were girls 50.0% (n=2554). According to the history of Hepatitis B vaccination by questionnaire of parents’, 91.2% [91.2-92.0] were vaccinated with Hepatitis B. The proportion was 89.7% [89.7-90.8] and 94.1% [94.1-95.2] in rural and urban areas, respectively. Nearly 90% [89.6-90.5] of children were vaccinated in hospitals, 2.3% [2.0-5.0] were vaccinated at home, 8.1% [7.9-10.7] were unaware of the study participants’ location of vaccination. There were no statistically significant differences by urban and rural residences. Vaccination coverage against Hepatitis B was 91.5% (n=2300) and 90.9% (n=2284) among boys and girls, respectively and 89.6% (n=4506) were vaccinated at hospitals. Vaccination coverage were similar by sex. We also used Health Documents /pink book of children/ or vaccination card for each child to determine the coverage. According to the data from the children’s vaccination card and health documents’, 917 (18.2%) children were not vaccinated against hepatitis, 57 (1.1%) children received 1 dose, 235 (4.7%) children received 2 doses, and 3818 (75.9%) children received all 3 doses of hepatitis B vaccine. There was no significant difference by sex, though the coverage varied by age. For instance, proportion of children with no written documentation in the vaccination card was 13.5% among children aged 1 years that increased to 22.5% and 25.3% among children aged 8 and 9 years, respectively. In contrast the coverage rate of 3 doses of hepatitis B vaccination declined from 77.8% to 70.7% among children aged 1 years and 9 years, respectively. Hepatitis B vaccination coverage according to the vaccination card was different by provinces and within the districts of Ulaanbaatar city. Conclusion A total of 5027 children aged 0-9 years were included in the study, of which 917 (18.2%) children were not vaccinated against hepatitis, 57 (1.1%) children were vaccinated against the first dose, 235 (4.7%) children were vaccinated against the second dose, and 3818 (75.9%) children were fully vaccinated against the first-third dose. Although the coverage of the study participants varied depending on age and place of residence, no significant differences were observed in terms of gender. The current rate of children who are not fully vaccinated stands at 18.2%, emphasizing the need to ensure all children receive full vaccinations for hepatitis B and the required five doses as per the schedule. Furthermore, it is essential to mandate booster vaccinations for those with delayed immunizations and improve the accuracy of registration data.

Background: According to the World Health Organization (WHO), 6.7 million people die annually due to air pollution caused by solid fuel use, with the majority of deaths resulting from respiratory diseases and cardiovascular conditions. In Mongolia, air pollution ranks as the fourth leading risk factor contributing to mortality, following hypertension, diabetes, and other major health risks. Although there have been numerous studies on outdoor air pollution in Mongolia, research linking indoor air pollution at the household level with the health status of residents remains limited. Aim: To compare indoor PM2.5 concentrations in households of Ulaanbaatar and Darkhan and examine their association with hypertension during the winter season. Materials and Methods: The study was conducted during November and December 2023, and January 2024, involving 240 households in Ulaanbaatar and Darkhan. Indoor PM2.5 concentrations were measured using Purple Air real-time sensors continuously for 24 hours over approximately one month. After measuring indoor air pollution, individuals aged 18–60 years living in the selected households were recruited based on specific inclusion criteria. Blood pressure was measured three times and the average value was recorded. Information on respiratory illnesses was collected through structured questionnaires. Statistical analysis was performed using STATA version 19.0. Results: A total of 241 households participated in the study, with 116 from Ulaanbaatar and 125 from Darkhan. Of the participants, 46.5% were male and 53.5% were female. In terms of housing type, 96 households (39.8%) lived in gers, 97 (40.2%) lived in stove-heated houses, and 48 (19.9%) lived in apartments. Among all participants, 66.0% (n=159) had hypertension and 34.0% (n=79) had normal blood pressure. Among participants aged over 40, 69.9–88.5% had hypertension, which is statistically significantly higher compared to younger individuals (p=0.0001). By body mass index, 75.3% (n=72) of overweight individuals and 78.4% (n=58) of obese participants had hypertension, showing a statistically significant difference compared to participants with normal weight (p=0.0001). The 24-hour average concentration of indoor PM2.5 was measured using the Purple Air device, and the levels in gers and stove-heated houses exceeded the limit set by the MNS 4585:2025 standard (37.5 µg/m³) Conclusion This study identified a relationship between environmental factors, such as air pollution and housing type, and the prevalence of hypertension. The indoor PM2.5 concentration in gers and stove-heated houses was above the standard limit, indicating a negative impact on the health of those residents. Furthermore, the high prevalence of hypertension among participants over the age of 40 and those who are overweight suggests a possible link to lifestyle and environmental conditions.

Backgroun: Air pollution is a major global public health concern that poses serious risks to human health regardless of a country’s level of economic or technological development. According to the World Health Organization (WHO, 2021), nine out of ten people worldwide breathe polluted air, and air pollution is responsible for the deaths of approximately 800 people every hour and 13 people every minute. Prolonged exposure to polluted air has been linked to a wide range of chronic illnesses, including chronic obstructive pulmonary disease (COPD), lung and bronchial cancers, asthma, and stroke. In Mongolia, air pollution reaches its highest levels during the winter months, particularly in Ulaanbaatar, where the majority of the country’s population resides. A study conducted by Enkhjargal G. (2012) reported that the concentrations of PM10 and PM2.5 in Ulaanbaatar were 7–8 times higher than the WHO recommended guidelines. In response to such challenges, many countries have increasingly adopted low-cost, direct measurement devices such as PurpleAir to monitor air quality. These devices are valued for their accessibility, network connectivity, and potential role in smart city pollution management systems. Despite their global application, there remains a lack of research in Mongolia on the use of PurpleAir sensors to measure PM2.5 concentrations and compare the results with official monitoring station data. Addressing this gap is essential for improving local air quality monitoring capacity and informing effective public health and environmental policies. Aim: Determination of PM2.5 particulate matter pollution in the outdoor environment of Ulaanbaatar city using a direct measurement device (Purple Air). Materials and Methods: A cross-sectional study design was employed. Direct measurement devices (Purple Air) were installed in selected districts of central Ulaanbaatar between December 2024 and February 2025, measuring PM2.5 concentrations at two-minute intervals over 24-hour periods. All data were statistically processed and analyzed using the SPSS-26 software package. Results: The average concentration of PM2.5 particles in the air of Ulaanbaatar city in winter is 66.68 μg/m3. Compared to the districts, the highest concentration was determined in SKHD (118.58±90.22 μg/m3), while the lowest concentration was determined in KHUD (42.37±43.51 μg/m3). Compared to the days of the week, the highest concentrations were measured on Monday (76.68±71.98 μg/m³), Saturday (77.50±71.63 μg/m³), and Sunday (80.34±74.45 μg/m³). The highest concentration of PM2.5 particles occurred from 6 pm to 1 am, and the lowest concentration was measured during the day (between 2 pm and 4 pm). The highest concentration of PM2.5 was measured in December (74.22±73.45 μg/m3), while the lowest concentration was measured in February (50.25±57.44 μg/m3). Conclusion The concentration of PM2.5 in the air of Ulaanbaatar city is 1.7 times higher than the general standard and technical requirements of Mongolia in winter, and the highest concentration is in the SKHD. The highest concentration of PM2.5 occurs more often in December and at night than in the winter months.

Background: Particulate matter with an aerodynamic diameter of 2.5 micrometers or smaller (PM2.5) penetrates deep into the alveoli through the respiratory tract and is characterized by its ability to induce oxidative stress, systemic inflammation, and vascular inflammation. Mongolia ranks among the countries with the highest levels of air pollution. In Ulaanbaatar, where more than half of the country’s population resides, wintertime PM2.5 concentrations often exceed 200 μg/m³, which is about eight times higher than the World Health Organization (WHO) guideline value. A study involving 1,200 adults in Ulaanbaatar showed that quality of life deteriorated sharply during periods of high air pollution, with effects more pronounced among individuals who already had impaired respiratory function. Aim: To examine the relationship between indoor household PM2.5 concentrations and lung function indicators among adults in Ulaanbaatar and Darkhan. Materials and Methods: This analytical cross-sectional study recruited adult participants from Ulaanbaatar and Darkhan through targeted sampling. Household air quality was measured using PurpleAir sensors, which were installed in participants’ homes for one month. After exposure measurement, lung function was assessed via spirometry. Statistical analyses were conducted using SPSS version 25.0. Results: A total of 236 participants were included: 114 (48.3%) from Ulaanbaatar and 122 (51.7%) from Darkhan. The sample consisted of 111 men (47.0%) and 125 women (53.0%). The mean indoor PM2.5 concentration was 66.24 μg/m³ (SD 44.87 μg/m³), ranging from a minimum of 7.79 μg/m³ to a maximum of 264.55 μg/m³. Stratification by housing type showed the highest PM2.5 levels in gers (82.34 μg/m³), followed by detached houses (67.34 μg/m³), while apartments had the lowest concentrations (32.24 μg/m³). Correlation analysis revealed statistically significant negative associations between PM2.5 levels and measures of expiratory function, including the FEV1/FVC ratio, peak expiratory flow (PEF), and mid-expiratory flow (FEF25–75). Reduced forced vital capacity (FVC) was observed in 9.4% of participants, reduced forced expiratory volume in one second (FEV1) in 15.3%, and a decreased FEV1/FVC ratio in 3.8%. Conclusion Indoor household PM2.5 concentrations were highest in gers, and expiratory flow-related lung function parameters showed significant negative associations with particulate exposure. This suggests that indoor PM2.5 primarily affects airflow limitation rather than overall lung volumes in this population.

The Western Pacific Region have the highest neonatal mortality rate of any country in the world. It has 37 countries and areas with approximately 1.8 billion people which comprises one-fourth of the total world population. The First Embrace It is care for all mothers and newborn infants. The components of the First Embrace are immediate and thorough dying, appropriately timed clamping and cutting of the cord, skin to skin contact and initiating exclusive breastfeeding for all newborns. Aim: First embrace and Early Essential Neonatal Care the importance of infant seeks to to learn some of the problems faced by identifying the skills of medical personnel. We were conducted in this study by a cross sectional questionnaire in order to assess the knowledge, attitude and practices of healthcare providers about essential newborn care and administrated a structured questionnaire to evaluate instruments and materials of the maternity wards.Skin to skin contact and a mother first embrace is the beginning of a healthy life is to reduce the newborn mortality. And the first embrace is improves the children’s immunity. We determined urgent problems for EENC including a lack of maternal health education, inadequate salaries for health care providers, a lack of essential medicines and commodities for birth preparation and numbers of health care providers delivering neonatal intensive care are increased due to the stillbirth rate has increased dramatically year by year.The first embrace is important to reduce neonatal mortality rate and 92.0% of all participants have the enough experiences for the first embrace care and 80.3% of all participants for the EENC.

Risk of nephrotith disease increases relating with using high hardened water, not suitable diet, being sensitive for some kind of food products. Then for Mongolia, particularly Bulgan province which is located in basin of the Selenge river is consisted in regions which have high hardened water. Sickness rate of renal diseases especially nephtolith disease is high in population of Selenge soum of Bulgan province. It was main reason of choose this subject and investigate non organic substances in urine of population and determine risks of nephtolith disease for them. To determine оne of the factors affecting the formation of the disease is to study the composition of drinking water and investigate non organic substances in urine. We used cross-sectional methodology for our study. Our study was conducted from June, 2013 to November, 2014. Household water used portable water dissemination and homes with private wells and water samples from the river.Drinking water analyzed of the chemistry parameters (13 substances) in the chemistry and toxicology laboratories in Orkhon aimag. There was 300 urine analyze was done and 62 of them was confirmed nephtolith disease with it. We investigated non-organic substances in their urine. Interviews people in the study, the average age was 43.26±14.7. 64.2% of participants was answered that they use ground water (private groundwater wells), 25.4% use external water (the well water), 8.1% use river water, 2.3 use pure water when asked about their water supply. Composition of samples from drinking water standard was near to the standard assessments by comparing the maximum amount of. We were considered the most important water pH, solids, iron, chlorine analysis compares removable wells and private wells. Hardness for 53.3% of the well of 2.5-3.5 mg/l with hard water, private wells, 60.0% of 4.6-5.5 mg/l solids by of water. Wells chlorides portable 66.7% 14.4-25.3 mg/l, and private wells 13.3% of 4.3-14.3 mg /l. 20.7 percent of survey identified as the kidney and urinary tract diseases. Urat salt (32.1%), compound of urat and sodium (32.1%), oxalate (14.5%), sodium (13.4%), compound of oxalate and sodium (6.4%), phosphate (1.5%) was determined in urine analyze. It was close to the water content of the standard performance. The well water solids of 2.5-3.5 mg/l and private groundwater wells solids of 4.6-5.5 mg/l. And the well chlorides 14.4-25.3 mg/l and private groundwater wells chlorides 4.3-14.3 mg/l.Urat and compound of urat and sodium are dominated in composition of stone during nephrolith disease (p=0.043).

Hepatitis B virus (HBV) infection is highly prevalent in Mongolia and its sequelae including liver cirrhosis and liver cancer are crucial public health problems in Mongolia. HBV infection is preventable through the vaccination. Universal hepatitis B vaccination has been introduced in 1991 after the 3 years field trial, making our country the 20th country with obligatory immunization against hepaitis B of all eligible population. In addition a penta vaccine (DTP+HipB+HBV) was introduced since 2005 in urban and rural areas. Although statistical information is available regarding the coverage of these hepatitis B vaccines, no study has been conducted on the coverage of hepatitis B vaccination based on the immunization cards of children that is important to reveal the current situation in the country. Objective: To study the coverage of Hepatitis B vaccination among children born after more than 10 years since its implementation in Mongolia. Materials and Methods: Nationwide cross-sectional survey was conducted during 2009-2010. A total of 5894 children was enrolled in this survey selected from Ulaanbaatar, Darkhan, Erdenet as well as 11 provinces and 50 soums. Iimmunization data of each child was abstracted from the health records or immunization cards at the actual Health Center, Local or Family hospital. The hepatitis B vaccination coverage was assessed by measuring HepB-birth dose, second and third dose. The vaccination status of the child was determined by counting the immunizations that were recorded by health/immunization registry or card. Data analyses was performed using SPSS 17.0 software. Results: A total of 5894 children were participated in the survey out of 6380 selected children (response rate 92.38%). Vaccination cards or registrations were available for 4944 (83.9%) children that was higher in rural areas compared to cities (Ulaanbaatar, Darkhan, Erdenet 75.5%, province centers 87.3%, soums 90.5%, p<0.001). In addition, the proportion of children with vaccination card was significantly decreased by age from age of 4 years to 6 years (p<0.0001). Vaccination coverage rate of those who received at least one dose of hepatitis B or penta vaccine was 98.6% [(95% confidence interval: 98.36-98.98) and 81.9% of them were fully vaccinated whereas 16.7% were partially vaccinated. Vaccination rate was 97.8% in Ulaanbaatar, Darkhan and Erdenet cities, 99.2% in province centers and 99.1% in rural soums. According to the results of 11 provinces and, coverage rate in provinces was 98.3%-100% where Umnugovi and Khentii provinces had highest rate (100%) and Selenge and Zavkhan provinces had lower rates (98.7%). Around 95% of the children were received the first dose of hepatitis B vaccine, of whom 3413 (76.5%) received within 24 hours while 1274 (27.8%) had received later than the schedule. Among study population 13.1% were vaccinated with penta vaccine that was introduced in 1995 in Mongolia. Conclusion: 1. Vaccination cards were available for 4944 (83.9%) children that was significantly higher in rural areas compared to cities. 2. Vaccination coverage rate of those who received at least one dose of hepatitis B or penta vaccine was 98.6% [(95% confidence interval: 98.36-98.98) and 81.9% of them were fully vaccinated whereas 16.7% were partially vaccinated. 3. Around 95% of the children were received the first dose of hepatitis B vaccine, of whom 3413 (72.8%) received within 24 hours while 1274 (27.8%) had received later than the schedule.