Objective: The risk of transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from schoolchildren to their household and the protective effects of vaccination in these settings remain poorly understood. We assessed the transmission dynamics of schoolchildren with SARS-CoV-2 within their households and the protective effects of coronavirus disease (COVID-19) vaccination among household members in Viet Nam. Methods: We estimated the attack rate, vaccine effectiveness and adjusted risk ratio (aRR) of factors associated with SARS-CoV-2 transmission to household contacts of children confirmed to have COVID-19 who attended three schools in Ha Nam, Phu Tho and Thanh Hoa provinces between September and December 2021 using multivariable regression with household-level random effects. Results: This retrospective cohort study included 157 children infected with SARS-CoV-2 and their 540 household contacts. The attack rate among household contacts was 24.6% (133/540). Overall, vaccine effectiveness among household contacts was 39% (95% confidence interval [CI]: -1 to -63), higher among males than females and higher in adults aged >40 years. COVID-19 transmission was greater among female household contacts compared with males (aRR: 1.35, 95% CI: 0.94 to 1.95), although not statistically significant, and highest among those aged 19–39 years (aRR: 2.51, 95% CI: 1.50 to 4.21). Fully vaccinated household contacts had significantly lower infection risk (aRR: 0.46, 95% CI: 0.26 to 0.84). Discussion: We found substantial onward transmission of SARS-CoV-2 from schoolchildren to household members, and older people were more likely to be protected by vaccination. We recommend that schoolchildren and all household members living with schoolchildren receive at least two doses of a COVID-19 vaccine. Recognizing the role of schoolchildren in the onward transmission of COVID-19 is an important lesson learned by Viet Nam that can help not only in managing other outbreaks but also in protecting schoolchildren by predicting the progress of the outbreak and preparing for a timely response.

In the present study, bioactivity-guided extraction and isolation of the n-hexane fraction of the fruits of Vietnamese Schisandra sphenanthera led to the isolation of five dibenzocyclooctadiene lignans as gomisin N (1), schisandrin C (2), gomisin H (3), gomisin D (4), and gomisin C (5). All the isolates were tested for their inhibition of NO production in LPS-induced RAW 264.7 cells. Among them, compounds 4 and 5 showed weak inhibition of NO production with IC 50 values of 25.0 ± 1.6 and 24.8 ± 2.0 µM, respectively. Compound 1 exhibited NO production inhibition with an IC 50 value of 15.8 ± 2.1 µM, meanwhile, schisandrin C (2) showed the most potent inhibition with an IC 50 value of 8.5 ± 0.5 µM. In addition, compound 2 had a concentrationdependent inhibitory effect on the protein expression of the inflammatory enzymes iNOS and COX-2. Their physicochemical properties and ADMET data were predicted by in silico, indicating favorable drug-like properties as well as low acute oral toxicity. The results suggest that the fruit of S. sphenanthera and its phytochemical constituents might be used as anti-inflammatory agents.

Background: Acne is a common disease in teenagers and young adults. This study was conducted to provide physicians with a better understanding of the disease and to improve their advice to patients. Objective: To define the prevalence of acne, it’s related factors and its psychological impact on the pupils at Chau Van Liem Senior High School. Method: A cross sectional descriptive study including 405 pupils in 10th, 11th, 12th grades was carried out by means of medical examination, and interviews based on questionnaires. Results: The prevalence of acne in Chau Van Liem Senior High School pupils is 82.5% overall. Separately, the incidence was slightly higher for boys with 83.9% than girls with 81.7%. Most of these pupils had moderate acne (51.5%), with 46.7% having mild acne. Only 1.8% had the disease at severe. Moderate acne was 1.72 times more common in males than females (p = 0.02, OR = 1.72). The essential lesions included oily skin, comedone, and papules, accompanied with pigmentation and/ or scar. One risk factor associated with acne was identified as the habit of using cosmetics (OR=2.12).The research also identified the differences between boys and girls in their habits related to acne. These included: the concern about acne (p=0.003), facial massage (p=0.02), using facial milk (p=0.001), using cosmetics (p=0.001). Acne led to diffident (p=0.01), depression (p=0.05), and ashamed (p=0.003). Boys with acne were less communicative than girls (p=0.03). Conclusion: The prevalence of acne in Chau Van Liem Senior High School pupils is 82.5%. Pupils still display bad habits like acne squeezing, applying cosmetics, using mixed- cream bought from the store or self concocted mixtures of locally obtainable creams including steroids, aspirin, antibiotics, vitamins, carelessly applying corticoid-contained medicine which harm their skin. Acne also affects their mental health, emotional well being, and performance in school, family relationships, and friendships.

Introduction: The need for gama \u2013 globulin, especially gama - globulin - anti \u2013 HBs, is huge in Vietnam. A number of patients cannot to afford use them due to the high price as they are imported. Meanwhile, Vietnam has high quality input sources for producing gama \u2013 globulin. \r\n', u'Objectives: To study the production process of gama - Globulin from Human Plasma and Standard gama - Globulin with Rich of Anti \u2013 HBs. \r\n', u'Subjects and method: 168 samples of human plasma from voluntary blood donors, which had been screened with for transfusion transmittable infections (TTLs), were chosen as plasma with rich of anti - HBs. The plasma with anti - HBsAg was precipitated with ethanol 25%, pH 6,9 to gain gama - globulin with rich anti - HBs, which was dried by Dutch Ly - 3 - TTE machine. Activation of anti - HBs gama - globulin was identified by a standard method of the degree of antibody specific for anti - HBsAg kit of BIORAD, \r\n', u'Results: The purity of the gama - globulin achieved was 93%, which was almost equal with the results of some foreign researchers (7.8), the activation of anti - HBs was 1:128 dilution degree. The productivity of gama - globulin gaining from 1 litter plasma was 6.0 gram. This new issue was first demonstrated in Vietnam. \r\n', u'Conclusion: We can domestically produce anti-Bs gama - globulin with high degree of activeness (1:128) from human plasma by the precipitating method with ethanol, pH and low temperature. \r\n', u'
Human plasma ; gama - globulin - anti - HBs ; Precipitation of ethanol ; pH and low temperature

Background: Acute gastroenterophathy usually caused by the Rota virus for children under 5 years old. Objectives: To present various types of data on epidemiology of ROTA virus diarrhea in Ho Chi Minh city from 12/2006-11/2007. Material and method: The data were collected from 500 stool specimens of diarrhea diagnosed chilren hosptalised at Thuy Dien Pediatric hospital 1, Ho Chi Minh city from December/2006 to November /2007. Results:There were 322 rotavirus-positive specimens, representing 64.4%. The proportions of monthly distribution of cases with diarrhea due to rotavirus were 90.1%, 54.39%, 85.37%, 74.51%, 72.92%, 41.67%, 26.67%, 58.33%, 79.31%, 52.63%, 69.05% and 57.78%, respectively. The numbers of rotavirus-positive cases in male and female were 216 (65.26%) and 106 (62.72%), respectively. The proportions of Rota virus positive children compared to total number of diarrheal cases with age 0-3, 3-6, 6-12, 12-24, 24-36 and over 36 months were 2.80%, 7.76%, 40.06%, 40.68%, 5.28% and 3.42%, respectively.\r\n', u'The results of typing identification indicated that the phenotypes of 98 among 100 specimens were identified (98%) in which there were sixty-one specimens of G1P8 (61%), one specimen of G2P8 (1%), fourteen specimens of G3P8 (14%), four of specimens of G4P8 (4%), eighteen specimens of GmixedP8 (18%). There were only two specimens of GnontypeableP8 (2%). Conclusion: Further studies should be carried out to clear this issue.\r\n', u'
Rotavirus ; gel type.

Background: Rotavirus type A is the most common cause of acute gastrointestinal inflammatory in children under 5 years old, especially in age groups 6 and 36 months. Some rotavirus strains are common; seen recently in Vietnam are G1, G2, G3, G4 and G9, P4, P6 and P8. Objective: Surveillance of epidemiological characteristics of rotavirus induced diarrhea in the National Pediatric Hospital from September, 2007 to March, 2008. Subject and methods: Collection of 322 stool specimens of pediatric patients with acute diarrhea (including 213 specimens from male, 109 specimens from female), who were treated in the National Pediatric Hospital. All of these specimens were determined for causes of rotavirus with the enzyme immunoassay (EIA). Results and Conclusion: Among these 322 stool specimens, there were 195 rotavirus positive specimens, accounted for 60.56%. The rate of monthly distribution of rotavirus diarrhea from September, 2007 to March, 2008 were 76%, 56%, 62%, 61%, 64%, 56% and 44%, respectively. Number of rotavirus positive cases in male and female was 56 (26.29%) and 79 (72.48%), respectively. The rate of rotavirus positive children compared to total number of specimens with the age 0-3 months, 3-6 months, 6-12 months, 12-24 months, 24-36 months and over 36 months was 7.69%, 15.9%, 41.54%, 32.82%, 1.54% and 0.51%, respectively. The results of type identification indicated that phenotypes of 37 among 40 specimens were identified (92.5%) in which there were 5 specimens of G1P8 (12.5%), 20 specimens of G3P8 (50%), 1 specimen of G9P8 (2.5%), 2 specimens of G1Pmixed (5%), 9 specimens of G3Pmixed (22.5%), 1 specimen of G unidentified-type P8 (2.5%) and 2 specimens of G3 P unidentified-type (5%).
rotavirus ; diarrhea ; epidemiology

Introduction and Purpose
Overweight and obesity have recently emerged as major problems of malnutrition among children in developing countries. However, risk factors for childhood obesity in Asian countries remain largely unknown. Identification of target populations for its prevention and intervention is urgently needed. This survey was conducted to assess the prevalence of overweight and obesity and identify possible risk factors among kindergarten children in Ho Chi Minh City, Vietnam.
Methods
In this cross-sectional study conducted in March, 2005, 780 children in their third and fourth years in kindergarten and their mothers were randomly selected from eight local kindergartens. Height and weight of mother-child pairs were measured, and an interview was conducted by trained staff using a questionnaire in Vietnamese. Overweight/obesity was defined as a weight-for-height > 2 SD above the National Center for Health Statistics median reference value. Risk factors for overweight/obesity were analyzed using logistic regression.
Results
There were 741 respondents (377 boys and 364 girls); the response rate was 95.0%. Average age of children was 61.8 ± 6.8 months; the average age of mothers was 35.0 ± 5.2 years. The average height and weight were 110 ± 5.7cm and 21.2 ± 4.0kg respectively. Of the 741 children, 27.8% were identified as being overweight/obesity. Four possible variables selected were: 1) child's sex, 2) mother's awareness of her child's current body type, 3) mother's expectation for her child's body type in the future, 4) mother's awareness of her own current body type .
Conclusion
Our findings point to the importance of addressing appropriate body images in the management of children's nutritional health. Providing sufficient amounts of information on appropriate body type in addition to feeding practice to mothers should be a priority at the Ho Chi Minh City Nutrition Center to prevent child overweight and obesity.

Background: In 24 years, Expanded Programe on Immunization\r\n', u'(EPI) at Thua Thien Hue province achieve high efficiency, reduce remarkably infection rate of children disease in EPI. Objectives: Assessment of instruments and cold chain at City, District Health Center and Commune Health station. Assessment of knowledge and practice EPI of medical officers in districts and communes. Subjects and method: Instrument, cold chain system and officers at City, District Health Center and Commune Health station. Method: Cross-section descriptive study; Observe instruments and cold chain at Health stations and fill in available forms. Interview medical officers, observe practical manipulation and fill in available forms. Results: The rate of good knowledge varied from 61,64% to 94,55% and the rate of appropriate practice was from 45,70% to 80,92%. On average, each commune health station had 0,421 refrigeration; 0,128 ice cabinet; 0,258 cold box; 2,259 thermoses; 6,623 ice packs; 2,826 thermometers and11,321 safe boxes. All commune health stations have vaccine containing thermos; one station has no thermometer; two have no safe box and five have no ice pack. Conclusion: All commune health stations have essential instruments, cold chain. Very few health station lack of one or some types. Medical officers almost have basic knowledge about expandedimmunization, the rate of answering right theoretical questions from 61,64% to 94,55%. Practical manipulation had still many errors, rate of manipulation right only 45,70% to 80,92%. District officers manipulated right higher than commune officers.\r\n', u'
Refrigeration/ instrumentation ; Vaccination/ instrumentation ; mortality ; methods ; Health Knowledge ; Attitudes ; Practice ;

Background: Open heart surgery with cardiopulmonary bypass (CPB) causes haemostatic abnormalities which result in postoperative excessive bleeding. Objectives: To investigate haemostatic disorders before - after CPB and postoperative bleeding. Subjects and methods: Sixty congenital cardiac patients with and without cyanosis were recruited consecutively. Hematology and coagulation tests were done 1 day before operation, 15 minutes after protamine administration, 2 and 6 hours after the operation in the intensive care unit (lCU). Mediastinal chest tube drainage (MCTO) was measured for the first 6h in the ICU. Results: Significant differences between 2 groups could be found for red blood cells, hemoglobin, hematocrit, fibrinogen, D-dimer, fibrinogen degradation products (FOP), von Kaulla and platelet aggregation to epinephrine before operation (p < 0.05). There were not significant differences in platelets, PT, APTT, platelet aggregation to adenosine diphosphate (AOP) in the acyanotic and cyanotic patients (p > 0.05). Most hematology parameters were decreased significantly and hemostasis measurements were prolonged after operation in both groups (p < 0.05). There was also the significant difference in MCTO between 2 groups (p < 0.05). Conclusion: Coagulation, hemostasis and fibrinolysis disorders; thrombocytopenia and acquired transient platelet dysfunction may be responsible for bleeding complications after CBP \r\n', u'\r\n', u'
Heart Defects ; Congenital/ pathology ; epidemiology ; Hemostatic Disorders/ pathology ; diagnosis

Background: In 2006, the project of global fund for malaria prevention in Vietnam provided a large number of rapid diagnostic test Paracheck F for Vietnam for the purpose of rapid malaria diagnose. However, there is no study on evaluation the effect of rapid diagnostic test compared with microscopy method. Objective: To evaluate the diagnostic yield and cost of paracheck F test and microscopy in malaria diagnosis and treatment. Subject and Method: The study was carried out in 6 communes belongs to Quang Tri and Quang Binh provinces from September to November - 2006. The study was divided into 3 phases. Phase 1: diagnoses and treatments are based on clinical symptoms, phase 2: diagnoses and treatments are based on the results of paracheck and phase 3: diagnoses and treatments are based on the results of microscopy. All phases, both the common patients and malarial patients and the amount of anti-malarial drugs were treated, the amount of money was spent on transport and days work off of malarial patients and their relatives were calculated. Result: The investigation data on expenditure of malaria patients showed that: the average direct cost of malaria patient in phase 1 is VND 116.100; phase 2: VND 119.400 and phase 3: VND 120.800 per 1 treatment course. There is no significant difference between direct costs in three phases (p > 0.05). Conclusion: The expense efficiency for finding out a case of malaria by paracheck and microscopy is equivalent and lower than the expense of diagnosis based on clinical symptoms.
Malaria diagnosis ; RDT Paracheck F ; microscopy