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.

Objective: The purpose of this study was to identify factors associated with twin pregnancy following day 3 double embryo transfer (DET). Methods: This retrospective cohort study incorporated data from 16,972 day 3 DET cycles. The participants were women aged between 18 and 45 years who underwent in vitro fertilization with intracytoplasmic sperm injection (IVF/ICSI) at My Duc Assisted Reproduction Technique Unit (IVFMD), My Duc Hospital, located in Ho Chi Minh City, Vietnam. Results: Of the 16,972 day 3 DET cycles investigated, 8,812 (51.9%) resulted in pregnancy. Of these, 6,108 cycles led to clinical pregnancy, with 1,543 (25.3% of clinical pregnancies) being twin pregnancies. Factors associated with twin pregnancy included age under 35 years (odds ratio [OR], 1.5; 95% confidence interval [CI], 1.32 to 1.71; p<0.001) and cycles involving the transfer of at least one grade I embryo. Relative to the transfer of two grade III embryos, the risk of twin pregnancy was significantly elevated following the transfer of two grade I embryos (OR, 1.40; 95% CI, 1.16 to 1.69; p<0.001) or a combination of one grade I and one grade II embryo (OR, 1.27; 95% CI, 1.05 to 1.55; p=0.001). Conclusion By analyzing a large number of IVF/ICSI cycles, we identified several predictors of twin pregnancy. These findings can assist medical professionals in tailoring treatment strategies for couples with infertility.

Objectives: The prevalence of posttraumatic stress disorder (PTSD) has increased, particularly among individuals who have recovered from coronavirus disease 2019 (COVID-19) infection. Health literacy is considered a “social vaccine” that helps people respond effectively to the pandemic. We aimed to investigate the association between long COVID-19 and PTSD, and to examine the modifying role of health literacy in this association. Methods: A cross-sectional study was conducted at 18 hospitals and health centers in Vietnamfrom December 2021 to October 2022. We recruited 4,463 individuals who had recovered from COVID-19 infection for at least 4 weeks. Participants provided information about their sociodemographics, clinical parameters, health-related behaviors, health literacy (usingthe 12-item short-form health literacy scale), long COVID-19 symptoms and PTSD (Impact Event Scale-Revised score of 33 or higher). Logistic regression models were used to examine associations and interactions. Results: Out of the study sample, 55.9% had long COVID-19 symptoms, and 49.6% had PTSD.Individuals with long COVID-19 symptoms had a higher likelihood of PTSD (odds ratio [OR], 1.86; 95% confidence interval [CI], 1.63–2.12; p < 0.001). Higher health literacy was associated with a lower likelihood of PTSD (OR, 0.98; 95% CI, 0.97–0.99; p = 0.001). Compared to those without long COVID-19 symptoms and the lowest health literacy score, those with long COVID-19 symptoms and a 1-point health literacy increment had a 3% lower likelihood of PTSD (OR, 0.97; 95% CI, 0.96–0.99; p = 0.001). Conclusion Health literacy was found to be a protective factor against PTSD and modified the negative impact of long COVID-19 symptoms on PTSD.

Purpose: Although some immune protection from close contact with individuals who have coronavirus disease 2019 (COVID-19) has been documented, there is limited data on the seroprevalence of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in individuals who were in lockdown with confirmed COVID-19 cases. This study investigated immunogenicity against SARS-CoV-2 in household members and people who lived near home-quarantined patients with COVID-19. Materials and Methods: This cross-sectional study was conducted during the community-based care that took place during lockdowns in District 10, Ho Chi Minh City, Vietnam from July to September 2021. SARS-CoV-2 antibody levels were determined in index cases of COVID-19, household contacts, and a no-contact group from the same area. Results: A total of 770 participants were included (355 index cases, 103 household contacts, and 312 no contacts). All index cases were unvaccinated, but >90% of individuals in the household and no-contact groups had received ≥1 vaccine dose. SARS-CoV-2 neutralizing antibodies (Nabs) were present in >77% of unvaccinated index cases versus 64%/65.4% in the householdo-contact groups (p=0.001). Antibody concentrations in unvaccinated index cases were significantly higher than those in household contacts and no contacts, with no difference between the latter groups. In all cases, antibody levels declined markedly ≥6 weeks after infection, and failed to persist beyond this time in the household and no-contact groups. Conclusion Community-based care may have helped to create community immunogenicity, but Nabs did not persist, highlighting a need for vaccination for all individuals before, or from 6 weeks after, infection with SARS-CoV-2.

Objective: To investigate antidiabetic and antioxidant activities of the extract and fractions from Vietnamese red seaweed Laurencia dendroidea. Methods: The seaweed Laurencia dendroidea was extracted by using microwave-assisted extraction method in 80％ methanol. The seaweed extract was then fractionated using different solvents (n-hexane, chloroform, ethyl acetate, butanol and water). These obtained fractions were evaluated for α-glucosidase inhibitory and antioxidant activities. Antioxidant activities were tested using DPPH, nitric oxide radical scavenging and metal chelating assays. The enzyme inhibition mode was determined using Lineweaver-Burk plot. For acidic and thermal stabilities, the ethyl acetate fraction was treated at pH 2.0 and 100 ℃, respectively. The residual inhibitory activity of the fraction was calculated based on the initial inhibitory activity. For in vivo antidiabetic activity, mice were divided into four groups, including normal control, diabetic control, diabetic mice treated with ethyl acetate fraction and diabetic mice treated with gliclazide. Blood glucose level of treated mice during acute and prolonged treatments was measured. To evaluate the toxicity of the ethyl acetate fraction, the body weight changes and activities of liver function enzymes (aspartate transaminase, alanine transaminase and gammaglutamyl transferase) were carried out. Results: The extract of Laurencia dendroidea showed strong α-glucosidase inhibitory and DPPH radical scavenging activities. Methanolic concentrations affected both α-glucosidase inhibitory and antioxidant activities. A 80％ aqueous methanol was the suitable solvent for extraction of enzyme inhibitors and antioxidants. Among solvent fractions, ethyl acetate fraction had the highest inhibitory activities against α-glucosidase with a mixed type of inhibition and the strongest antioxidant activities, and was stable under acidic and thermal conditions. The ethyl acetate fraction treated diabetic mice significantly reduced blood glucose level compared with the diabetic control group (13.16 mmol/L vs. 22.75 mmol/L after 3 hours of treatment). Oral administration of ethyl acetate fraction did not exhibit toxicity at a dose of 100 mg/kg body weight as determined by body weight changes and liver biochemical parameters. Conclusions: Laurencia dendroidea could be a potential source for production of antidiabetic and antioxidative agents.

Objective: The purpose of this survey was to estimate the prevalence of viral load (VL) suppression and emergence of HIV drug resistance (HIVDR) among individuals receiving antiretroviral therapy (ART) for 36 months or longer in Viet Nam using a nationally representative sampling method. Methods: The survey was conducted between May and August 2014 using a two-stage cluster design. Sixteen ART clinics were selected using probability proportional to proxy size sampling, and patients receiving ART for at least 36 months were consecutively enrolled. Epidemiological information and blood specimens were collected for HIV-1 VL and HIVDR testing; HIVDR was defined by the Stanford University HIVDR algorithm. Results: Overall, 365 eligible individuals were recruited with a mean age of 38.2 years; 68.4% were men. The mean time on ART was 75.5 months (95% confidence interval [CI]: 69.0–81.9 months), and 93.7% of the patients were receiving non-nucleoside reverse transcriptase inhibitor-based regimens. Of the 365 individuals, 345 (94.7%, 95% CI: 64.1–99.4%) had VL below 1000 copies/mL and 19 (4.6%, 95% CI: 2.8-–7.5) had HIVDR mutations. Discussion Our nationally representative survey found a high level of VL suppression and a low prevalence of HIVDR among individuals who received ART for at least 36 months in Viet Nam. Continued surveillance for HIVDR is important for evaluating and improving HIV programs.

Background: Fungal keratitis is a serious ocular infection that can cause corneal scarring and blindness. Currently, diagnosis of fungal pathogens remains a difficult problem. Objectives: To investigate the application of semi-nested PCR targeted ITS genes for detection of fungal agents causing keratitis. Material and method: Ten identified fungal strains, 4 bacterial strains, 20 scraping samples from patients with suspected fungal keratitis and 2 scraping samples from patients with suspected bacterial keratitis were tested using semi-nested PCR. Results: Semi-nested PCR showed positive results for the samples of identified fungal strains and for the 20 scraping samples from patients with suspected fungal keratitis. Neither samples of bacterial strains nor scraping samples from suspected bacterial keratitis patients gave positive PCR results. Conclusion: Semi-nested PCR is a robust tool for specific and rapid detection of fungal agents causing keratitis.
Fungal keratitis ; semi-nested PCR

Background: According to WHO, there are 5 million deaths from kinds of injury a year in the world, of which 875000 deaths occur in children under 18 years old. Injury leads to 40000 deaths which account for 10.7% deaths due to all other causes a year in VietNam. Objective: To show conclusions of the situation of child injury, recommendations for prevention of child injury and methods in order to enhance emergency activity in Vietnam. Subjects and method: The authors collected information about all patients who had emergencies due to injury at Viet Duc hospital, from March 26th 2006 to Octorber 26th 2006. However, supervised cases were the patients under 18 years old who were examined and treated at the Department of Emergency. Results: During the period of study, 2536 patients under 18 years old were examined for injury, of which death and coming back home for death were 83 cases (3.27%). 974 children had emergency resulted from injury: male was more than female: 697 verus 227. The leading causes of child injury were fall and traffic accident, respetively 34% and 60%. The most common traumas were traumatic brain injury (45%), limbs injury (41%). Although most of cases had first aid at the hospitals in district or province level, the rate of non-first aid cases was high (34%). Conclusion: Child injury is a leading cause of child death in hospitals. Methods for prevention of child injury should focus on educating and propagandizing to minimize injuries caused by traffic accident and fall.
Wounds and Injuries ; Child

Objectives: Described on the knowledge of STDs of male and female patients at NIDV from 2002 to 2004 and described the knowledge on the STDs prevention in these groups. Methods: The cross-sectional study have implemented in NIDV from 2002 to 2004 by face to face interview, physical examination and laboratory tests of STD patients. Result and conclusions: Total 109 subjects were interviewed, male (56.9% men, 43% women). Most of STD patients had been heard on STDs (90.8%). Most of the patients think STDs are infection disease (87.2%); the main transmission ways are through sexual intercourses and injections (91.7%), but the knowledge in male were higher than female. The most popular media is TV, radio and newspapers (83.5%). The lower communication is in the school (15.6%), particularly from parent's patients (8.2%). The communication from friends has been mainly in male (56.5%). Most of STDs patients had been known the methods of STDs prevention are condom (57.8%) and monogamous (40.4%), but the knowledge in men were also higher than in women.
Sexually Transmitted Diseases ; Knowledge ; Patients

Survey on epidemiology and habits of seeking medical services of 109 patients with sexual transmitted diseases (STDs) (62 male and 4 female) at National Dematology Hospital shows that prevalence is higher among youth (20-39); state workers 33.9%; mostly in urban areas (68.8%); people had high school education and more (77.4%). Most women had married (60.9%); while most men have been single (89.2%). Male patients often contracted STDs due to having sexual activities with partners or sex workers (81.6%). Female patient contracted STDs mainly through husband (85%). Most STD patients seek for medical service within the next days (77.9%) or months. Those who came to hospitals/dermatology institute/dermatology centre was 53.2% and those who came to private clinics and chemistry for self treatment is 31.1%.
Sexually Transmitted Diseases, Epidemiology, Habits