Search

Summary: Background: Beta-lactams remain the first-line treatment of Streptococcus pneumoniae infections despite the increasing global prevalence of penicillin-resistant/non-susceptible strains. We conducted a cross-sectional household survey in a rural community in northern Vietnam in 2018–2019 to provide prevalence estimates of penicillin non-susceptible S. pneumoniae (PNSP) carriage and to investigate behavioural and environmental factors associated with PNSP colonization. The data presented will inform the design of a large trial of population-based interventions targeting inappropriate antibiotic use. Methods: A survey was conducted between July 2018 and April 2019, encompassing 1502 individuals from 324 households. A total of 1, 498 samples from nasal and nasopharyngeal swabs were cultured on blood agar plates supplemented with 5 μg of gentamicin. S. pneumoniae colonies were confirmed by MALDI-TOF. Penicillin susceptibility was tested by E-test. Logistic regression models were used to explore risk factors for PNSP carriage compared to susceptible strains. Findings: We recovered 132 S. pneumoniae isolates out of 1148 swabs. Antibiotic susceptibility results were obtained for 97% (128/132). Of these, 76% (97/128) were PNSP (MIC ≥ 0.12 μg/ml) and 77% (99/128) were non-susceptible to three or more antibiotics. After adjusting for age and wealth, antibiotic use was not associated with PNSP carriage. Participants more likely to be colonized with PNSP were young (≤20-years) and more frequently ate meat and dairy products, particularly pork (adjusted OR 52.30 [95% CI 8.72–313.60]) and milk derivatives (aOR 12.48 [4.01–38.82]). Consumption of fermented food was a protective factor (aOR, 0.02 [

Summary: Background: Antimicrobial resistance (AMR) is a silent pandemic causing 1.27 million deaths in 2019, disproportionately affecting low- and middle-income countries, but resistance among commensal microbiota and the determinants of carriage have not been widely reported. This cross-sectional household study aimed to determine the prevalence of carbapenem-resistant (CRE) and third-generation cephalosporin-resistant Enterobacterales (C3GRE) in a rural community in Ha Nam northern Vietnam, as well as the socio-demographic, behavioural, and environmental determinants of carriage. Methods: 1502 individuals across 324 households were surveyed between July 2018 and April 2019. Faecal samples were cultured on meropenem and ceftazidime supplemented media to identify CRE and C3GRE, respectively. Logistic regression models were used to explore risk factors for CRE and C3GRE carriage compared to susceptible strains. Findings: Colonisation with C3GRE and CRE was 94.0% (95% Confidence Interval (CI) 93.5%–94.4%) and 1.9% (1.6%–2.2%), respectively. The CRE prevalence was too low to explore determinants. Antibiotic use in the last month (adjusted OR 1.22 [95% CI 0.45–3.31]) and recent illness (aOR 1.48 [0.34–6.51]) were not associated with C3GRE carriage. Variables associated with C3GRE carriage were high-income (OR 0.29 [0.12–0.74]), worse sanitary conditions (aOR 4.35 [1.07–17.43]), and frequent beef consumption (aOR 6.56 [2.16–19.98]). A protective association between C3GRE carriage and animal husbandry was observed in children under 5-years (aOR 0.27 [0.09–0.84]). For participants 5-years and older, chicken consumption was associated with increased likelihood of C3GRE carriage (aOR 3.45 [1.45–8.22]), while a protective association was observed for regular tofu (aOR 0.32 [0.14–0.74]) and fermented food consumption (aOR 0.55 [0.31–0.96]). Interpretation: In this high-prevalence setting, colonisation with C3GRE was not associated with individual antibiotic use, while environmental exposures, including food and sanitary conditions, were associated with C3GRE colonisation. Further research is required to understand the mechanisms behind these associations. Funding: This work was supported by Oxford University Clinical Research Unit internal grants in Vietnam from the Wellcome Trust Africa Asia Programme core grants (2015-2022—106680/Z/14/Z, and 2022-2029—225167/Z/22/Z).

Objectives: SARS-CoV-2 transmission and epidemic potential is related to the population's immunity levels. As such, assessing different regions’ preexisting immune responses to SARS-CoV-2 is important to understand the transmission potential of emerging SARS-CoV-2 variants. Design: In 975 serum samples from Vietnam (2014 to 2019), anti-SARS-CoV-2 Immunoglobulin G levels were determined by enzyme-linked immunosorbent assay. Plaque reduction neutralization test (PRNT) was performed using Wuhan strain and variants of concern (VOCs). Cross-reactivity was confirmed by analyzing B-cell receptor (BCR) repertoire sequences and identifying BCR repertoire sequences-derived T-cell epitopes. Results: Overall, 20.9% (n = 76/364) and 9.2% (n = 7) demonstrated SARS-CoV-2 neutralizing activity (PRNT50) against the Wuhan and Alpha strain, respectively. Neutralizing activity against Beta, Gamma, and Delta strains was absent (PRNT50

Background: Diphtheria cases reported in Central Vietnam since 2013 were mainly in children aged 6-15 years, which may reflect an immunity gap. There is little information on population immunity against diphtheria in countries without a school-entry booster dose. We aimed to measure the age-stratified seroprevalence of anti-diphtheria toxoid antibodies, quantify the change in antibody levels in individuals over time, and estimate the length of protective immunity after vaccination in well-vaccinated communities in Vietnam.Methods: An age-stratified seroprevalence survey among individuals aged 0-55 years was conducted at Nha Trang, Vietnam. The same participants were followed up after two years to quantify the change in antibody levels. IgG was measured using ELISA. The length of protective immunity after vaccination was estimated using a mixed-effect linear regression model with random intercept.Results: Overall seroprevalence was 26% (95%CI:20-32%). Age-stratified seroprevalence was 68% (95%CI:4-11%), 7% (95%CI:4-11%), 12% (95%CI:7-19%), 33% (95%CI:27-40%), and 28% (95%CI:17-43%) among those aged ≤5, 6-15,16-25, 26-35, and 36-55 years, respectively. The antibody levels declined by 47% (95%CI:31-59%) over two years, and the predicted duration of vaccine-derived protective immunity after receiving four doses was 4.3 years (95%CI:3.5–5.3) among participants aged six years or younger.Conclusion: Given the low seroprevalence and short period of vaccine protection, a school-entry booster dose (5-7 years) is recommended in Vietnam.

Background: Vietnam implemented various public health interventions such as contact tracing and testing, mandatory quarantine, and lockdowns in response to coronavirus disease 2019 (COVID-19). However, the effects of these measures on the epidemic remain unclear.Methods: This article describes the public health interventions in relation to COVID-19 incidence. Maximum likelihood estimations were used to assess containment delays (time between symptom onset and start of isolation) and multivariable regression was employed to identify associated factors between interventions and COVID-19 incidence. The effective reproductive numbers (Rt) were calculated based on transmission pairs.Results: Interventions were introduced periodically in response to the epidemic. Overall, 817 (55.4%) among 1474 COVID-19 cases were imported. Based on a serial interval of 8.72 ± 5.65 days, it was estimated that Rt decreased to below 1 (lowest at 0.02, 95% CI 0–0.12) during periods of strict border control and contact tracing, and increased ahead of new clusters. The main method to detect cases shifted over time from passive notification to active case-finding at immigration or in lockdown areas, with containment delays showing significant differences between modes of case detection.Conclusions: A combination of early, strict, and consistently implemented interventions is crucial to control COVID-19. Low-middle income countries with limited capacity can contain COVID-19 successfully using non-pharmaceutical interventions.

Summary: Background: Influenza virus, respiratory syncytial virus, parainfluenza virus, and metapneumovirus are the most common viruses associated with acute lower respiratory infections in young children (