Safety and immunogenicity of inactive vaccines as booster doses for COVID-19 in Turkey: A randomized trial

Plain Language Summary What is the context? The timing of the primary and booster doses for each vaccine differs. We aimed to evaluate the safety and immunogenicity of CoronaVac and TURKOVAC vaccines used as homologous booster dose after CoronaVac primary vaccination. What is new? The neutralizing antibody titers against the Wuhan variant decreased below 1/6- the seropositivity threshold value- in more than 55% of the participants 4 months after administration of two doses of CoronaVac vaccine. Immunogenicity was re-stimulated and the neutralizing antibody titers increased rapidly and markedly with the administration of the CoronaVac or TURKOVAC as a booster dose 4 months after the second dose. While the increase in neutralizing antibodies against the Wuhan variant was similar with both CoronaVac and TURKOVAC, more antibodies developed against the Delta variant with TURKOVAC. What is the impact? With the Hybrid COV-RAPEL TR study, after the primary vaccination consisting of two doses of inactivated vaccine, antibody titers decreased in the long term; however, higher antibody titers are achieved than the primary vaccination after the booster dose administered after 4-6 month interval. Booster application with TURKOVAC provides antibodies at least as much as the CoronaVac booster dose, with an acceptable safety profile

Long-Term Results of Immunogenicity of Booster Vaccination against SARS-CoV-2 (Hybrid COV-RAPEL TR Study) in Turkiye: A Double-Blind, Randomized, Controlled, Multicenter Phase 2 Clinical Study

The immunogenicity of vaccines decreases over time, causing a need for booster doses. This study aimed to present the long-term (Day 84) immunogenicity results of the double-blind, randomized, controlled, phase II Hybrid COV-RAPEL TR Study (NCT04979949), in which the TURKOVAC or CoronaVac vaccines were used as a booster after the second dose of primary vaccination with CoronaVac. A total of 190 participants from the Hybrid COV-RAPEL TR Study, who had both Day 28 and Day 84 immunogenicity results, were included. The immunogenicity on Day 84, regarding the neutralizing antibody positivity (Wuhan and Delta variants) and anti-spike immunoglobulin (Ig) G (IgG) antibody positivity, was compared between TURKOVAC and CoronaVac vaccine arms according to sex and age groups. Overall, antibody positivity showed a slight decrease on Day 84 vs. Day 28, but was not different between TURKOVAC and CoronaVac arms either for sexes or for age groups. However, TURKOVAC produced better antibody response against the Delta variant than CoronaVac, while CoronaVac was superior over TURKOVAC regarding neutralizing antibody positivity in the 50–60 years age group, regardless of the variant. A single booster dose, after the completion of the primary vaccination, increases antibody positivity on Day 28 which persists until Day 84 with a slight decrease. However, an additional booster dose may be required thereafter, since the decrease in antibody titer may be faster over time

Changes in antimicrobial resistance and outcomes of health care-associated infections

To describe the change in the epidemiology of health care-associated infections (HAI), resistance and predictors of fatality we conducted a nationwide study in 24 hospitals between 2015 and 2018. The 30-day fatality rate was 22% in 2015 and increased to 25% in 2018. In BSI, a significant increasing trend was observed for Candida and Enterococcus. The highest rate of 30-day fatality was detected among the patients with pneumonia (32%). In pneumonia, Pseudomonas infections increased in 2018. Colistin resistance increased and significantly associated with 30-day fatality in Pseudomonas infections. Among S. aureus methicillin, resistance increased from 31 to 41%

Tocilizumab treatment in severe COVID-19: a multicenter retrospective study with matched controls

Coronavirus disease-2019 (COVID-19) associated pneumonia may progress into acute respiratory distress syndrome (ARDS). Some patients develop features of macrophage activation syndrome (MAS). Elevated levels of IL-6 were reported to be associated with severe disease, and anti-IL-6R tocilizumab has been shown to be effective in some patients. This retrospective multicenter case-control study aimed to evaluate the efficacy of tocilizumab in hospitalized COVID-19 patients, who received standard of care with or without tocilizumab. Primary outcome was the progression to intubation or death. PSMATCH (SAS) procedure was used to achieve exact propensity score (PS) matching. Data from 1289 patients were collected, and study population was reduced to 1073 based on inclusion-exclusion criteria. The composite outcome was observed more frequently in tocilizumab-users, but there was a significant imbalance between arms in all critical parameters. Primary analyses were carried out in 348 patients (174 in each arm) after exact PS matching according to gender, ferritin, and procalcitonin. Logistic regression models revealed that tocilizumab significantly reduced the intubation or death (OR 0.40, p = 0.0017). When intubation is considered alone, tocilizumab-users had > 60% reduction in odds of intubation. Multiple imputation approach, which increased the size of the matched patients up to 506, provided no significant difference between arms despite a similar trend for intubation alone group. Analysis of this retrospective cohort showed more frequent intubation or death in tocilizumab-users, but PS-matched analyses revealed significant results for supporting tocilizumab use overall in a subset of patients matched according to gender, ferritin and procalcitonin levels