Introduction: Hearing loss is an important public health issue that negatively affects children’s speech, cognitive development, academic performance, and social interaction. Even mild hearing impairment may lead to adverse developmental outcomes. However, data on hearing loss among primary school children in Mongolia remain limited. Goals: To determine the prevalence, type, and severity of hearing loss among primary school students in Ulaanbaatar and to assess associated socio-demographic factors. Material and Method: A school-based cross-sectional study was conducted among 1,254 primary school students. Hearing screening was performed using pure-tone audiometry following a standardized protocol. Students who failed the screening were referred for confirmatory diagnostic audiometry. Hearing loss was classified as mild (21–35 dB), moderate (36–50 dB), and severe (≥50 dB). Socio-demographic data were collected using a structured questionnaire. Statistical analysis data were analyzed using RStudio software. Descriptive statistics were used to summarize participant characteristics. Associations between hearing loss and independent variables were examined using chi-square tests and logistic regression analysis. Variables with p<0.20 in univariate analysis were included in the multivariable logistic regression model. Odds ratios (ORs) with 95% confidence intervals (CIs) were reported, and p<0.05 was considered statistically significant. Ethical considerations: The study protocol was approved by the Institutional Ethics Committee (Approval No. 2024/3 06). Written informed consent was obtained from parents or legal guardians, and assent was obtained from participating students prior to data collection. Results: Of the 1,254 students, 116 (9.2%) required further evaluation, and hearing loss was confirmed in 23 students (1.8%). Most cases were mild in severity. Paternal education level was significantly associated with hearing loss (p=0.028), whereas no significant associations were observed for sex or household income. Conclusion The prevalence of hearing loss among primary school students in Ulaanbaatar was 1.8%, with most cases being mild and unilateral. These findings highlight the importance of implementing regular school-based hearing screening programs and improving parental awareness of children’s hearing health.

Background: Hearing loss among adolescents remains an important public health concern, as even mild degrees of hearing impairment can adversely affect cognitive development, academic performance, and social interaction. In Mongolia, evidence on the prevalence of hearing loss among school-aged children is limited, providing the rationale for conducting this study. Aim: To determine the prevalence, type, and severity of hearing loss and to assess associated demographic factors among middle and high school students in Ulaanbaatar, Mongolia. Materials and Methods: A school-based cross-sectional study was conducted during 2024–2025 among 1,803 students from 18 general education schools across nine districts of Ulaanbaatar. Hearing screening was performed using pure-tone audiometry according to a standardized protocol, and students who failed the initial screening underwent confirmatory audiometric testing. Hearing loss was classified as mild (21–35 dB), moderate (36–50 dB), or severe (≥50 dB). Demographic information was collected from parents or guardians using a structured questionnaire. Data were analyzed using R software. Associations were assessed using the chi-square (χ²) test, with p<0.05 considered statistically significant. Result: Among the students screened, 7.4% were identified as requiring further evaluation, and hearing loss was confirmed in 2.3%. Parental educational level was significantly associated with hearing loss, while no significant differences were observed by sex. Conclusion The prevalence of hearing loss among middle and high school students in general education schools in Ulaanbaatar was 2.3%, with no significant difference by sex. Most identified cases were mild and unilateral, highlighting the need for regular school-based hearing screening and strengthened parental health education. The association between parental educational level and hearing loss suggests the importance of addressing social determinants, and further studies are warranted to explore additional risk factors such as the use of personal listening devices.

Background: Simulation-based education has become an effective and widely used modern teaching method in health professional education. This approach allows students to apply theoretical knowledge into practice and develop essential skills such as clinical assessment, clinical decision-making, and teamwork in a safe and controlled learning environment. In recent years, international studies have demonstrated that simulation-based training improves students’ clinical skills, confidence, communication abilities, and professional attitudes. However, evidence regarding the effectiveness of simulation-based training remains limited in certain educational settings, particularly in developing countries. Therefore, evaluating the effectiveness of simulation-based training within local educational contexts is necessary. Aim: To evaluate the effectiveness of simulation-based training on students’ knowledge, clinical skills, and professional attitudes. Materials and Methods: This study included 45 third-year medical students from four classes at the Mongolian National University of Medical Sciences using a random sampling method. Participants were divided into two groups according to the training modality: a simulation-based training group (n=20) and a traditional learning control group (n=25). Knowledge was assessed before and after training using an 18-item test covering asthma etiology, pathophysiology, clinical features, diagnosis, and treatment. After the training session, students’ knowledge, clinical skills, and professional attitudes were evaluated using a 21item Likert-scale questionnaire and small-group discussions to identify factors influencing learning outcomes. The reliability of the questionnaire was evaluated using Cronbach’s alpha, which demonstrated high internal consistency (α=0.90). Statistical analysis was performed using SPSS software. Paired samples t-tests were used to compare pre- and post-training knowledge within groups, while independent samples t-tests were used to compare post-training outcomes between groups. Result: After training, mean knowledge scores significantly improved among all participants (pre-training: 9.18±2.33; post-training: 10.47±2.31; p<0.001). In the simulation group, knowledge scores increased from 7.65±2.01 to 9.05±2.46, while in the control group, scores increased from 10.40±1.80 to 11.60±1.41 (p=0.007). Post-training comparisons showed that the simulation group demonstrated higher mean scores in knowledge (36.70±3.73 vs 34.44±4.77) and clinical skills (11.35±1.69 vs 10.92±1.75) than the control group; however, these differences were not statistically significant (p>0.05). Professional attitude scores were significantly higher in the simulation group compared with the control group (43.35±3.60 vs 40.64±4.51, p=0.034). Conclusion Simulation-based training demonstrated positive effects on students’ knowledge and clinical skills and significantly improved professional attitudes. Integrating simulation-based training with traditional teaching methods may serve as an effective educational strategy to enhance the quality of clinical education.

Background: Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis, and approximately 5% of new cases are diagnosed with multidrug-resistant tuberculosis (MDR-TB). Since 2019, a shorter treatment regimen comprising 6–7 oral medications has been introduced for MDR-TB management. Although some of the newer drugs used in short regimens are associated with significant side effects, their potential nephrotoxicity has not been fully studied. Estimation of glomerular filtration rate (GFR) is a primary method for evaluating renal function. Objective: Evaluation changes in renal filtration function during the course of short and long treatment regimens for MDR-TB. Goals: To evaluate changes in GFR at different stages of treatment both regimens, and to compare the treatment outcomes between long and short regimens. Materials and Methods: A retrospective chart review was conducted among 103 patients diagnosed with MDR-TB and treated at the TB Dispensary of Bayangol District Health Center between 2017-2024. GFR was calculated using MDRD equation. Data statistically analyzed using SPSS 23.0. Results: Of the study participants, 71 (66.35%) received the long treatment regimen, while 32 (29.90%) received the short regimen. The mean age was 34.81 years for the long-regimen group and 39.59 years for the short-regimen group. In the long-regimen group, the mean eGFR (mL/ min/1.73m²) was 90.016 at the start, 75.82 at the mid-point, and 77.23 at the end of treatment. In the short-regimen group, the respective eGFR values were 68.47, 68.2, and 72.5. Additionally, 54.92% of participants in the long-regimen group received injectable treatment. Conclusion eGFR values were lower in the short treatment regimen group compared to the long regimen group. While the cure rate was higher in the short regimen group, the mortality rate was also significantly higher. Therefore, treatment success cannot be attributed solely to the type of regimen used.

Background: Tick-borne encephalitis is human viral infection involving the nervous system and transmitted by the bite of infected tick. The TBE Virus is distributed in different geographical areas by three widespread subtypes of the virus: The Far East, Europe, and Siberia. The Far East type has a mortality rate was 30-35%, the European type has a mortality rate of 2.2%, and the Siberian type has a mortality rate of 6-8% (A.G. Pletnev, 1998) [2].
In recent years, human cases of tick-borne infections have been reported in 19 European countries and four Asian countries (Mongolia, China, Japan, and South Korea) [3].
Human cases of tick-borne encephalitis, tick-borne rickettsiosis, and tick-borne borreliosis have been registered in Mongolia since 2005. Deaths have been reported year by year [5].
During 2005 to 2021, tick-borne rickettsiosis (71.6%), tick-borne encephalitis (17.3%) and tick-borne borreliosis (52.9%) were confirmed by epidemiological, clinical and laboratory tests at the NCZD.
Tick-borne encephalitis was registered in 63 soums of 15 provinces and 9 districts of the capital city, of which 90% were infected with tick bites in Selenge and Bulgan provinces. The average mortality rate is 4.9% (14), of which 28.6% in Bulgan province and 2.7% in Selenge province.
Tick-borne encephalitis is the leading cause of death in Bugat soum of Bulgan province and more infected men about 40 years of age [7]. Purpose : Collect ticks from selected soums of the provinces, identify tick species, species composition, distribution, tick densities, pathogens of tick-borne diseases, conduct population surveys to assess the risk of tick-borne infections, and identify tick-borne infections. Material and Method: Ticks were collected by flag from birch trees in birch forests and meadows with biotope and overgrown berries, determined morphological analyze and molecular biological investigation for detecting tickborne pathogens.
Questionnaires were collected from selected soum residents according to a specially designed randomized epidemiological and clinical survey card, collected information and forms were submitted to soum hospitals with a history of tick bites (according to clinical criteria). Serological tests were performed to detect IgG-specific antibodies to the collected serum mites. Result and conclusion Collected 121 ticks (120 I. persulcatus and 1 D. nuttalli) and not wound egg, larvae, nymphs. By molecular biological investigation detected 3.5% of I.persulcatus from Khutag-Undur soum of Bulgan province, 3.5% of anaplasmosis, and 14.1% of I.persulcatus mites from Bugat soum. 1.5% borreliosis, 3.1% anaplasmosis.
Detected DNA of 100% tick-borne rickettsiosis from D.nutalli ticks and determined circulation of infection among tick in Bugat and Khutag-Undur soums of Bulgan province.
247 people were surveyed, 56 blood serum from cases. Detected Q fever, erysipelas, and anaplasmosis, tick-borne borreliosis 3 (5.4%), tick-borne rickettsiosis 26 (46.4%), Japanese encephalitis 3 (5.4%), tick-borne encephalitis tick-borne rickettsiosis 6 (13.0%), tick-borne rickettsiosis tick-borne borreliosis 1 (1.8%), tick’s rickettsiosis Japanese encephalitis 1 (1.8%), tick-borne encephalitis tick-borne borreliosis 1 (1.8%).
By investigation, vaccination (88%) and wearing long-sleeved shirts and pants (81%) were the most effective ways to prevent tick bites (81%) [15]. According to our research, the percent of population knowledge in Bulgan province was insufficient (40.9%) which there is a lack of information, training and advertisement among the population in the province.

The microbiologist, who aged 44 man has work with glander DNA extraction between January and March at 2022, was developed sumptoms with fever, headache, muscle pain, weakness, cut throat, cough at 4 March, 2022. On March 7, he had tested Covid-19 and the result was negative. He was given 1gr tefazoline by eight-time interval for two days. Despite completing the therapy, episodes of fever and headache increased. A medical evaluation, which included MRI test was no disorder was developed. On March 12, painful with leg and developed muscle pain. He continued to difficulty to walk and cough, fever and weakness. On March 13, he has admitted hospital with diagnoses pneumonia.
He had continued sign with pneumonia in both lung, fever, infiltration with right leg, cough, headache, and glandule node in hospital. By PCR test, glander DNA was detected in sputum in National Center for Zoonotic Diseases laboratory. He recovered 20 days in hospital.
He has 12 days incubation period and infection route was by worked with glander strain and it was pneumonia form with laboratory-acquired human glanders.
Human glander case is rare in Mongolia. Three human glander cases had registered in 1966, 1972, 1977 among prison’s horse herder in Mongolia.

Background: Medical geography deals with the application of major concepts and theories derived from human and physical geography to issues of health and disease. Between1970-1980, Russian scientists were first figured landscape, geographical distribution of TBE in Mongolia. Since human cases of TBD were registered from 2005, around 2000 cases of TBD were registered. From 15% of diseases and 78% of fatal cases were tick-borne encephalitis. Therefore, were tried to create current geographical distribution of TBE in Mongolia and detect risk areas. Мaterials and Methods: 287 TBE cases data, information of TBE positive tick and human data were analyzed which registered in NCZD between 2005-2017. Arc GIS 9 were used for create map. Mongolian map was divided by 5 landscape range such as forest-taiga, forest-steppe, steppe, steppe-desert, gobi and high mountain. Result: In forest-taiga range, 57% of TBE cases and incidence was 9.51 per 10000 population. 56.4% of I.persulcatus tick, 1.9% of D.nuttalli tick were found and infection rate of tick was Ixodes persulcatus-6.97%, Dermacentor nuttalli-5.2%. Seroprevalence of TBE was 25±12.1 among population.
In forest-steppe range, 40% of TBE cases and incidence was 0.56 per 10000 population. 43.6% of I.persulcatus tick, 44.3% of D.nuttalli, 24.4% of D.silvarum tick tick were found and infection rate of tick was Ixodes persulcatus-3.08%, D.silvarum-1.56% and D.nuttalli-1.56%. Seroprevalence of TBE was 14.5±11 among population.
In steppe range, 0.7% of TBE cases and incidence was 0.12 per 10000 population. 62.2% of D.silvarum tick, 23.9% of D.nuttalli tick were found and infection rate of tick was D.nuttalli-2.81% and D.silvarum-1.2%. Seroprevalence of TBE was 16.3±6.5 among population.
In other range including steppe-desert, gobi and high mountain, 2.8% of TBE cases and incidence was 0.1-0.27 per 10000 population. 62.2% of D.silvarum tick, 47.6% of D.nuttalli tick were found and infection rate of tick was D.nuttalli-0.84%. Seroprevalence of TBE was 2.5-13.1 among population. Conclusion Natural foci of tick-borne encephalitis have been registered in all landscape ranges of Mongolia and higher risk area of those ranges were forest-taiga and forest-steppe. Dermacentor silvarum, Dermacentor nuttalli tick becoming dominant vector of TBE in steppe range.

Background: The knowledge about the normal and abnormal vaginal microbiome has changed over the last years. The normal and the abnormal vaginal microbiota are complex ecosystems of more than 200 bacterial species influenced by genes, ethnic background and environmental and behavioral factors. Major changes in the vaginal physiology and microbiota over a woman’s lifetime are largely shaped by transitional periods such as puberty, menopause and pregnancy. Many studies have shown that bacterial vaginitis (BV) has an increased risk of preterm birth, miscarriage, premature rupture of membran, and postpartum uterine inflammation and sepsis. To assess different bacterial and epidemiological factors associations with increased vaginal pH in the women of reproductive age. Methods: In the 1st Health center of Bayanzurkh district hospital, 100 non-pregnant women were randomly selected between 18-45 years of age. Women were submitted to an interview, vaginal examination and vaginal specimen collection for pH measurement and microscopy. Descriptive statistics are reported for the vaginal pH according to a specially designed survey card, the survey respondents assessed the status of the mother’s health. Results: The non pregnant group studied herein were mostly young adults with ages in the age range 25-29 (32.0; 32%, mean±SD: 29.1±5.7) years. The vaginal pH mean in non-pregnant women was 4.5±0.5. Elevated vaginal pH was signicantly associated with bacterial vaginosis (p < 0.001), and bacterial vaginosis flora (p < 0.001). 162 of 200 women (81%) had an increased vaginal pH. 65,8% of participants in research were normal nugent score. Conclusion In non-pregnant women, the vaginal pH mean was 4.5 ± 0.5. Changes in vaginal pH are statistically significant with age, and clinical manifestations. /р<0.05/. The human vaginal ecosystem is a dynamic environment in which microbes can affect host physiology but also where host physiology can affect the composition and function of the vaginal microbiota.

Objective: To retrospectively analyze the drug resistant characteristics and distribution of multi-drug resistant bacteria infection in State Second General Hospital. Methods: Total 772 cases treated in our hospital from January 2017 to September 2019 were selected as subjects. The automatic microorganism analyzer VITEC-2 and manual method were used for bacterial identification; Kirby-Bauer disk diffusion method was used for susceptibility test; WHONET 5.6.2019 software and EXCEL 2013 were used to analyze the distribution and drug sensitivity of isolated bacteria. Results: Among the 772 strains of multi drug resistant bacteria, the proportion of Gram-negative bacteria was 84.9%, and the proportion of Gram-positive bacteria was 15,1%; fluconazole resistant candida accounted for 3.2%. Multi -drug resistant bacteria mostly distributed in sputum, accounting for 23.5%; 50.5% multi-drug resistant strains were from intensive care unit.
Resistant rates of Escherichia Coli ESBL, Klebsiella ESBL and Enterobacter spp to cephalosporins and penicillin were 100%. Resistant rates of staphylococcus aureus to antibacterial agents; cephalosporins and penicillin were 100%. Conclusion Gram-negative bacteria were the main multi-drug resistant bacteria of our study in our hospital, mainly distributing in Intensive care unit patients. They are highly resistant to most antibacterial agents, which provides a theoretical basis for the prevention and control of multi-drug resistant bacteria infection in hospital.

Backround: Hematology departments of health laboratories, over capital city and 21 provinces both of governmental and private sectors in this country, have to take responsibilities for providing hematology analysis. A wide range of technology and methods have been implemented among these laboratories. Harmonization of the hematology investigations of different laboratories with standard service all over the country is the major goal to reach. We organized the MEQAS (Mongolian External Quality Assessment Scheme) since 2008 on basis the Cooperation agreement between Ministry of Health and Sysmex Corporation in the establishment of Hematology external quality control and reference laboratory system in Mongolia. This is the report of our 8-year experience of MEQAS as the national project, covering increasing numbers of laboratory members. In 2008-2017 years we set up total 18 MEQAS in Mongolia. Materials and Methods:
Survey Materials
In each survey, the following three different of survey materials were used;
Sample A : Hematology Control Material 1*
Sample B : Hematology Control Material 2*
Sample C : Fresh Whole Blood Sample**
*Hematology Control Material provided by Sysmex Corporation
**Under cooperation of National Center for Transfusiology, a fresh whole blood sample was drawn from a healthy donor and prepared on the same day of sample delivery, according to the procedures reported by Kondo H et. all.
Standard Analyzers
3 units of fully-automated standard analyzers (KX-21, pocH-100i, XS-1000i), installed at the Shastin Central Hospital, were used to assign the target values for the survey materials. These standard analyzers have been calibrated with SCS-1000® before the survey, and monitored with hematology controls, e-CHECK(XS) ® and EIGHTCHECK-3WP® on daily basis.
Instructions & Sample Distribution
On every survey, the workshop was held to give guidance and distribute the survey samples to each participant.
Categorization of Peer Group
Participating data were divided into two peer groups, based on methodology; Group 1: laboratories used automated hematology analyzer (in further Auto’s), Group 2: manually examined group. Each laboratory was given ID number and was asked to analyze these samples 3 times and report the all data and average for CBC 8 parameters.
Statistical Evaluation Method
For individual reports, the results for each participant were evaluated and expressed according to peer group mean and standard deviation index (SDI), Precision index (PI), Absolute evaluation, Scoring system and Target-value evaluation methods (A B C D evaluation). Results:
The Auto’s inter-lab CV% of WBC for fresh whole blood showed decrease from 6.1 to 4.2 comparing with17^th and 18th MEQAS.
The Auto’s Inter-lab CV% of RBC for fresh whole blood showed decrease from 3.7 to 3.4 comparing with 17^th and 18^th MEQAS.
The Auto’s inter-lab CV% of HGB for fresh whole blood were very stable (2.9%, 3.0%), respectively from 17^th to 18^th MEQAS.
The Auto’s inter-lab CV% HCT for the fresh whole blood showed go down from 5.5% to 4.8% comparing with 17^th and 18^th MEQAS.
The Auto’s inter-lab CV% PLT for fresh blood showed go down from 10.2% to 8.2% comparing with 17^th and 18^th MEQAS.
The Auto’s inter-lab CV% of CBC parameter for fresh blood and control Material (Sample A) showed go down from 1^st to 18^th MEQAS.
The Auto’s inter-lab CV% of WBC, RBC, HGB, PLT for Control Material (Sample A) were big difference comparing with Japan’s CV%. Conclusion:
1. The Auto’s inter-lab CV% of WBC, RBC and PLT for fresh whole blood has been decrease respectively 4.2%, 3.4%, 8.2% in the 18^th MEQAS and there was difference in the CV% between manufacturers.
2. The Auto’s inter-lab CV% of WBC, RBC, HGB, PLT for Control Material (Sample A) showed go down from 1^st to 18^th MEQAS but were big difference comparing with Japan’s CV%. Acknowledgements We would like to express our appreciation to the Sysmex Corporation (Japan) for providing financial supports investigate this study.