Background: Respiratory viral and bacterial infections are one of the leading causes of hospitalization and death worldwide, particularly affecting children, the elderly, and immune compromised individuals. The detection of causative pathogens is crucial for understanding the epidemiology, prevention, management, and treatment of severe pneumonia. Molecular diagnostic methods provide high sensitivity and speed, enabling the simultaneous detection of viral and bacterial co-infections. Aim: Detection of single and combined viral and bacterial infections in hospitalized children with pneumonia using multiplex PCR. Materials and Methods: We conducted a cross-sectional study design involving 100 hospitalized participants at the National Center for Mothers, Newborns, and Women II. The study utilized questionnaires and laboratory analysis methods. Nasopharyngeal swabs were collected from the participants using a sterile swab and transported in a UTM transport medium (Jiangsu, China). After nucleic acid extraction using the STARMag 96 ProPrepC assay, the samples were analyzed with the Seeprep 32 automated analyzer (Seegene Inc., Korea). Real-time polymerase chain reaction (PCR) analysis was performed using the Allplex™ RV Master Assay and Allplex™ PneumoBacter Assay (Seegene Inc., Korea), with the CFX-96 system (BioRad Inc., USA). Results: The prevalence of viral infections in the study population was as follows: influenza type A 3% (n=3), influenza type B 3% (n=3), total influenza virus 14% (n=14), respiratory syncytial virus 18% (n=18), adenovirus 10% (n=10), rhinovirus 20% (n=20), and SARS-CoV-2 5% (n=5). No bacterial infections, such as B.parapertussis or L.pneumophila, were detected. However, bacterial infections identified included B.pertussis in 1% (n=1), C.pneumoniae in 2% (n=2), H.influenzae in 43% (n=43), M.pneumoniae in 52% (n=52), and S.pneumoniae in 45% (n=45). Of the 100 children in the study, 6% had influenza or influenza-like illness. Among these, 43% had the virus alone, and 14% had a viral co-infection. Bacterial infections were detected individually in 40% of cases, with co-infections in 46% of bacterial cases. Conclusion Metapneumovirus, B.parapertussis, and Legionella pneumophila were not detected in the study participants (0%). Among the viral infections, respiratory syncytial virus (18%, n=18) and rhinovirus (20%, n=20) had the highest prevalence. For bacterial infections, H.influenzae (43%, n=43), M.pneumoniae (52%, n=52), and S.pneumoniae (45%, n=45) were most commonly detected.

The number of tick borne diseases is increasing in the world. More than 100000 tick borne encephalitis, tick borne encephalitis cases were registered every year. It occurred in 29 Europien, 4 Asian countries and became public health concern [1]. In our country, virus, tick detection started since 1980 with collaboration Russian scientists. From 1998, collaborative team of Public Health Institute (PHI), National centre for communicable diseases (NCCD), National center for infectious diseases with natural foci (NCIDNF) and Rssian scientists started study of tick prevalence and infection of tick borne encephalitis in Khuvsgul, Khentii, Bulgan, Orkhon, Tuv province. In study of B.Byambaa, M.Dash (1994), 18 species tick were found in Mongolia. Ticks found in 27 soums of 7 provinces. TBE virus infection of tick was 1.2-16.7% in I.persulcatus, 13.7-20% in D.nutalli. Far eastern subtype founded from patient, Siberian subtype founded from tick in Bulgan province of Mongolia. TBEV infection was 1.1-39% among population; highest infection was in Bugan, Khuder soum of Selenge province, Dadаl soum of Khentii provinces. 57.2-59.4% of population was tick bitten and 21-73.7% of them were developed clinical symptoms during surveillance. Symptoms include redness, fever, headache, skin rash, join paint. Most TBE cases were developed fever, headache, vomiting, stiff neck, paralysis. 96% of them typical, 4.4% of them atypical, 60% of them fever, 13.3% meningial, 10% meningoencephalitis among 90 cases in 1998-2004. In review, clinical symptoms of TBE cases that occurred Mongolia similar to cases caused Sibirein subtype.

Background: Natural protection against Mycobacterium tuberculosis is based on cell-mediated immunity, which most importantly involves CD4+ and CD8+ T-cell subsets. Therefore, the evaluation of CD4+ and CD8+ T-cell profi les are important to evaluate cell-mediated immunity. Immuno-regulating therapy is important in increase of T cell subsets. Objective: To determine some T-cell subsets in active pulmonary tuberculosis patients following immunoregulating treatment in intensive phase of antituberculosis treatment, so to evaluate the treatment effect. Method: This study was conducted in TB clinic of National Center for Communicable Diseases (NCCD) between Aug 2008 and Mar 2009. CD4+ and CD8+-T cells were evaluated in 50 active pulmonary tuberculosis (infi ltrative form) cases before antituberculosis treatment (25 cases with Salimon-Study group, 25 cases without SalimonControl group) Patients with chronic disease, pregnant and alcohol users are excluded. The T cell subsets count was performed by FACSCount fl ow cytometer at the Immunology Laboratory of the NCCD,Mongolia.The monoclonal antibodies to CD3, CD4 and CD8 (Becton Dickinson) were used for the analysis. Result: CD4 count was 605,1242,7 cells/microL, CD8 count-470,92235,7 cells/microL, CD3 count-1130,7425,6 cells/microL, CD4/CD8 ratio was-1,480,67. CD4, CD8, CD3 cells were signifi cantly lower (P=0.05) in active pulmonary TB patients than in healthy Mongolian. And these subsets were signifi cantly lower in older patients (>50 age).There was no statistical signifi cance in sex and other age groups (p>0, 05). There were statistical signifi cances such as CD4 count, CD4/CD8 ratio (CD4-733,95314,38 cells/micro, CD4/CD8 ratio-1.870,7 in treatment group, CD4-570,54213.07 cells/micro, CD4/CD8 ratio-1.260.45 in control group) between TB and control group at the end of intensive phase of antituberculosis treatment (=0,05, =0,001). However, there were not any signifi cance CD8 count and CD3 count between two groups (CD8-423,68174,28 cells/microL, CD3-1212,27453,98 cells/microL in treatment group, CD8-500,67203,74cells/microL, CD3 -1139,33 386,47 cells/ microL in control group) (=0,05). Conclusion: 1. T cell subsets were signifi cantly lower in active,new,smear positive, pulmonary TB patients than in healthy Mongolians (p=0.05). 2. The statistical signifi cance is observed in 50 years and older TB patients (p=0.05). 3. CD4, CD4/CD8 were signifi cantly higher in patients treated with immuno-regulating treatment than in patients of control group (=0,05, =0,001).