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The emergence of drug resistant typhoid fever is a major public health problem, especially in Asia. An oral single dose typhoid vaccine would have major advantages. M01ZH09 is a live oral single dose candidate typhoid vaccine containing Salmonella enterica serovar Typhi (Ty2 aroC(-)ssaV(-)) ZH9 with two independently attenuating deletions. Studies in healthy adults demonstrated immunogenicity and an acceptable safety profile.We conducted a randomised placebo controlled, single-blind trial to evaluate the safety and immunogenicity of M01ZH09 in healthy Vietnamese children aged 5 to 14 years.Subjects were randomly assigned to receive either a nominal dose of 5x10(9) CFU of M01ZH09 or placebo and were followed up for 28 days. The primary safety outcome was the proportion of subjects with any adverse event attributed to M01ZH09. The primary immunogenicity endpoint was the proportion of subjects who showed a positive immune response to M01ZH09 in the Salmonella Typhi lipopolysaccharide (LPS) specific serum IgA and IgG ELISA.One hundred and fifty-one children were enrolled, 101 subjects received M01ZH09 and 50 subjects received placebo. An intention to treat analysis was conducted. There were no serious adverse events and no bacteraemias. In the M01ZH09 group, 26 (26%; 95% CI, 18-5%) of 101 subjects experienced adverse events compared to 11 (22%; 95% CI, 12-36%) of 50 subjects in the placebo group (odds ratio (OR) [95%CI] = 1.23 [0.550-2.747]; p = 0.691). Faecal shedding of S. Typhi (Ty2 aroC(-)ssaV(-)) ZH9 was detected in 51 (51%; 95% CI, 41-61%) of 100 M01ZH09 subjects. No shedding was detected beyond day 3. A positive immune response, defined as 70% increase (1.7 fold change) in LPS specific serum IgG (day 14 or 28) and/or 50% increase (1.5 fold change) in LPS specific serum IgA (day 7 or 14) from baseline was detected in 98 (97%; 95% CI, 92-99%) of 101 M01ZH09 recipients and 8 (16%; 95% CI, 7-29%) of 50 placebo recipients. Twenty-eight (100%; 95% CI, 88-100%) of 28 vaccine recipients who were evaluated in the LPS specific IgA ELISPOT assay showed a positive response compared to none of the 14 placebo recipients tested.This was the first phase II trial of a novel oral candidate typhoid vaccine in children in an endemic country. M01ZH09 had an appropriate safety profile and was immunogenic in children.Controlled-trials.com ISRCTN91111837.

Background: An endotracheal tube cuff pressure between 20 and 30 cmH2O is recommended to prevent ventilator-associated respiratory infection (VARI). We aimed to evaluate whether continuous cuff pressure control (CPC) was associated with reduced VARI incidence compared with intermittent CPC., Methods: We conducted a multicenter open-label randomized controlled trial in intensive care unit (ICU) patients within 24 hours of intubation in Vietnam. Patients were randomly assigned 1:1 to receive either continuous CPC using an automated electronic device or intermittent CPC using a manually hand-held manometer. The primary endpoint was the occurrence of VARI, evaluated by an independent reviewer blinded to the CPC allocation., Results: We randomized 600 patients; 597 received the intervention or control and were included in the intention to treat analysis. Compared with intermittent CPC, continuous CPC did not reduce the proportion of patients with at least one episode of VARI (74/296 [25%] vs 69/301 [23%]; odds ratio [OR] 1.13; 95% confidence interval [CI] .77-1.67]. There were no significant differences between continuous and intermittent CPC concerning the proportion of microbiologically confirmed VARI (OR 1.40; 95% CI .94-2.10), the proportion of intubated days without antimicrobials (relative proportion [RP] 0.99; 95% CI .87-1.12), rate of ICU discharge (cause-specific hazard ratio [HR] 0.95; 95% CI .78-1.16), cost of ICU stay (difference in transformed mean [DTM] 0.02; 95% CI -.05 to .08], cost of ICU antimicrobials (DTM 0.02; 95% CI -.25 to .28), cost of hospital stay (DTM 0.02; 95% CI -.04 to .08), and ICU mortality risk (OR 0.96; 95% CI .67-1.38)., Conclusions: Maintaining CPC through an automated electronic device did not reduce VARI incidence., Clinical Trial Registration: NCT02966392., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America.)