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.

Study 208 patients with cirrhosis were investigated in the Hospital 198 from May 1995 to May 2003. Among them 31 (30 males and 1 females)- 14,9% had got hepatic encephalopathy syndrome, its incidence increased proportionately with the duration of the disease cirrhosis alcoholism patients got higher incidence of hepatic encephalopathy with viral hepatitis factor. The incidence of hepatic encephalopathy reached 23% in case of viral infection associated with alcoholism . In patients with gastrointestinal hemorrhage there were 30%, with diabetes 40%, hypokalemia 33%, kidney failure 40% had got hepatic encephalopathy syndrome. Clinical syndroms of hepatic encephalopathy were amnesia, dementia, insomnia and mental disorder.
Risk factors ; Diagnosis ; Fibrosis ; Epidemiology ; Alcoholism ; Gastrointestinal Hemorrhage ; Diabetes Mellitus ; Hypokalemia ; Kidney Failure

Study conducted on 56 patients with gastrointestinal bleeding because of gastroduodenal ulcer with H. pylori (+) and 27 with H. pylori (-), treated at the Hospital 19/8 in ther period of 1995-2000. These 2 groups were similar at age, gender, duration of the disease and at the first time of bleeding. Results showed that in H. pylori (+) group, there are the symptoms of cardiovascular colapsus and of bleeding, recurred after 3 years of follow-up. In this group anemia and the bleeding were more severe
Helicobacter pylori ; Peptic Ulcer ; Esophageal Diseases ; complications ; Hemorrhage

127 cirrhotic patients in Hospital No 198 from 1996 to 2002 were enrolled in this study. Analysing the rate and degree of gastrointestinal bleeding in accordance with risk factors, the results showed that 28% of cirrhotic patients had experienced gastrointestinal bleeding. The more severe cirrhosis was, the higher rate of gastrointestinal bleeding. Alcohol addiction increased the rate of gastrointestinal bleeding rather than hepatitis B virus and hepatitis C virus. When combined 2 factors, the rate of gastrointestinal bleeding increased 1.5 times. The rate of gastrointestinal bleeding increased according to degree of esophageal varices
Fibrosis ; Esophageal Diseases ; Diseases

6500 patients were performed gastroscopy at Hospital No 198 from 1997 to 2002. The results showed that 19 patients (0.29%) experienced gastric cancer. Common clinical symptoms are belch, difficulty of swallow, choking, pain under breastbone. 42.1% of patients had gastric cancer on middle third, 36.8% on lower third, and 21% on upper third. Funggosity is most common. Carcinoma accounts for 68.4%. Only 3/19 cases could be operated. So it's important to screen for endoscopy in order to find early gastric cancer
Endoscopy ; Esophageal Diseases ; Carcinoma

This study was conducted from the year 1997 to 2002 in the Hospital N 198, involving 300 patients with HBsAg (+) (Group A) and 150 patients with HBsAg (-) (Group B), all had liver and bile pathology. There were an analogy in age, gender, and the time of onset of clinical symptoms. Results showed that there is an prevalence of epithelial liver carcinoma (15%) in the group of HBsAg (+) higher than the the group of HBsAg (-) – only 5.3%. The risk of liver cancer in HBsAg (+) patient group with OR=3.1, the mean age of liver cancer patient group; the characteristics lower than HBsAg (-) patient group; the characteristics of cancer damage, the complications and the prognosis were analogous in 2 groups
Hepatitis B Surface Antigens ; Carcinoma, Hepatocellular ; Hepatitis B

The study carries on 55 patients diagnosed ulcerative colitis by sign of clinical and endoscope at 108 hospital of ministry of public security. The result: the age group 20 – 40 met usualy with 61.8%, clinical sign as abdominal pain is 81.8%, diarrhea 78.1%, constipation 23.8%, defecation bleeding 83.6%. Symptom of examination: aglobulia 33.7%, leucocytosis 41.8%. The result of endoscopy: ulcerative colitis of entier 7.2%, of transverse colon 16.3, of descending colon 27.2%. The result treatment: patients used corticoid has effect good with 87.3% clearance ulcer, ulcerative pool miniature 9%, 3.6% patients treated ineffect
Peptic Ulcer ; Endoscopy ; Colitis, Ulcerative

In 1994-2000 year period, from 6275 patients at Hospital No 108, 62 patients (37 males and 25 females) with stomach polyps were chosen for study. Results: stomach polyps occupied 0.98% of patients of endoscopic examination. 72.5% of patients have been above 40 years old. The clinical symptoms were not specific and their could be the associated symptoms of stomach injury – 90.3% of patients number had only 1 polyp, 85% of patients had the polyps in pylorus antrum. The polyp with diameter under 3 cm occupied 93.1%. 25.8% had a normal stomach image. Associated damages were gastritis, duodenal ulcer, stomach ulcer. 44/62 patients with stomach polyps (70.9%) had H. pylori. Hyperplasic polys accounts for 72.5%, gland epithelial polyps 20.9%
Stomach Diseases ; Stomach Neoplasms ; Endoscopy

On 100 liver cirrhosis patients treated in the Hospital 198 (32 with gastrointestinal hemorrhage and 68 without) prothrombine level, fibrinogen and thrombocyte level are related to the complications of gastrointestinal hemorrhage due to a rupture of esophageal verous varicosis in patient of cirrhosis. The amount of hemorrhagic group with a decrease of 80% of prothrombine occupies 71.8%, while in the group without hemorrhage only 41.4%. In hemorrhagic group, fibrinogen level more decrease than the group without hemorrhage (40.6% vs 30.8%) and the number of thrombocyte in hemorrhagic group is lower. The severity of gastrointestinal hemorrhage is related proportionally with the decrease of prothrombine level, fibrinogene level and thrombocyte number
Liver ; Cirrhosis ; Diseases

From Jan 1992 to Jan 2001, at the Hospital N0198, 405 diabetes patients aged 17-73 were studied. Results showed a rate of high blood pressure of 19% among diabetes patients, this rate was similar in male as in female gender. The most common age was 50-59 year old age, which accounted for 31.8%. Among patients with diabetes of type 1, the rate accounted for 19.4%, type 2 18.8%. The rate of kidney complications of diabetes patients with high blood pressure was 33.9%, while without high blood pressure ones was 11.3%. The rate of eyefundus complications was 33.9% and 9.2% respectively
Hypertension ; Diabetes Mellitus ; Blood Pressure