Effectiveness of Inactivated and mRNA COVID-19 Vaccines Against SARS-CoV-2 Infection, Severe Disease and Mortality in the Geriatric Population.

Older age (>60 years) has been identified as the main risk factor for COVID-19. In this study, we aimed to evaluate the efficacy of Pfizer-BioNTech and CoronaVac vaccines against COVID-19 infection, serious illness, and mortality in the geriatric population. We found that 2 doses of CoronaVac vaccine were ineffective in protecting against COVID-19 infection in people over 65 years of age, while the vaccine efficacy (VE) of the mRNA vaccine against COVID-19 was 80% (95% CI 70-87). The VE of full vaccination with BioNTech was 89% (95% CI 53-97) against hospitalization, 79% (95% CI 0-97) against death, and 79% (95% CI 0-97) against intensive care unit (ICU) admission. However, the VE of full vaccination with CoronaVac was 50% (95% CI 33-63) against hospitalization, 53% (95% CI 26-70) against ICU admission, and 56% (95% CI 30-73) against death. In conclusion, we found that the mRNA vaccine has higher efficacy against severe COVID-19 infection and mortality in the geriatric population than the inactivated vaccine. Booster doses of vaccines should be considered in increasing the effectiveness of inactivated vaccines. Given the potential of SARS-CoV-2 mutations evading vaccination protection and the risk of reduced immunity over time, regular monitoring of vaccine effectiveness in the real world is critical.

SARS CoV-2 reinfection rate is higher in the Omicron variant than in the Alpha and Delta variants.

BACKGROUND AND OBJECTIVES: Many mutations in variants for instance Delta and Alpha are associated with immune evasion and higher infectious potential. There are uncertainties regarding Omicron. In this regard, we aimed to compare the frequency of reinfection of SARS CoV-2 variants in our hospital between April 22, 2021 and January 26, 2022. METHOD: The reinfection rates and demographic characteristics of a total of 27,487 COVID-19 patients infected with different SARS CoV-2 variants were examined. RESULTS: Reinfection was found in 26 (0.46%) of 5554 Alpha, 209 (1.16%) of 17,941 Delta, and 520 (13.0%) of 3992 Omicron variants. A statistically significant difference was observed between the reinfection rates of the variants (p = 0.000). The mean reinfection days were calculated as 204.4 ± 51.1 in the Alpha variant, 291.2 ± 58.2 in the Delta variant, and 361.2 ± 131.6 in the Omicron variant (p = 0.000). It was observed that 16.5% of reinfection cases caught COVID-19 for the second time 3-6 months after the first COVID-19 infection, 36.7% after 6-12 months, and 46.8% after more than 12 months. There was a significant difference between the times in reinfection cases. Most reinfections occurred more than 12 months apart. Among those with a reinfection time > 12 months, 0% had Alpha, 3.4% had Delta, and 96.6% had Omicron variants. CONCLUSION: The highest reinfection rate was observed in the Omicron variant. Reinfection was approximately 30 times more frequent in the Omicron variant than in the Alpha variant and 10 times more frequent in the Delta variant.

Risks of catching COVID-19 according to vaccination status of healthcare workers during the SARS-CoV-2 Delta variant dominant period and their clinical characteristics.

The exposure of healthcare workers (HCWs) to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been a major concern since the beginning of the coronavirus disease 2019 (COVID-19) pandemic. The study aimed to investigate the relationship between vaccination status and the status of catching COVID-19 in HCWs working in a Training and Research Hospital in Turkey, and the clinical course of the disease in those who were caught. The vaccination status of 1279 HCWs working at Siirt Training and Research Hospital during the period when the SARS-CoV-2 Delta variant was dominant, their cases of catching COVID-19 during this period, and the clinical course of the disease in patients with COVID-19 were investigated retrospectively.  We found that the rate of COVID-19 transmission was lowest in fully vaccinated HCWs (p < 0.05). The rate of COVID-19 transmission in HCWs who received two doses of BioNTech vaccine (4.4%) and two doses of CoronaVac+ one dose of BioNTech vaccines (2.7%) was considerably lower than those without vaccination (26.2%) (p < 0.05). The transmission rate was lowest among those vaccinated with two doses of CoronaVac+ one dose of BioNTech. Hospitalization was not required in fully vaccinated HCWs. The lymphocyte count was found to be significantly higher in fully vaccinated patients than incompletely vaccinated and unvaccinated patients. Although C-reactive protein (CRP), d-dimer, and ferritin values were higher in unvaccinated and partially vaccinated patients than in fully vaccinated patients, the differences were not statistically significant. As a result, the transmission rate of COVID-19 was lowest in fully vaccinated HCWs and in those vaccinated with two doses of CoronaVac+ one dose of BioNTech. In fully vaccinated HCWs, hospitalization was not needed.

Evaluation of bacterial agents isolated from endotracheal aspirate cultures of Covid-19 general intensive care patients and their antibiotic resistance profiles compared to pre-pandemic conditions.

BACKGROUND: Early reports have shown that critically ill patients infected with SARS-CoV-2 have a high prevalence of nosocomial pneumonia, particularly ventilator-associated pneumonia (VAP). METHOD: In the present study, we determined the bacterial agents isolated from endotracheal aspirate (ETA) cultures of Covid-19 general intensive care patients and evaluated the antibiotic resistance profiles of common bacterial agents compared to the pre-pandemic period. RESULTS: While a total of 119 significant growths with polymicrobial growths were detected in the ETA cultures of 73 (7.5%) of 971 patients hospitalized in the intensive care unit before the pandemic, 87 significant growths were detected in the ETA cultures of 67 (11.1%) of 602 patients hospitalized in the Covid-19 intensive care unit (ICU) after the pandemic. While 61 (83.6%) of patients in the ICU died before the pandemic, 63 (94.0%) of patients in the Covid-19 ICU died after the pandemic. In terms of age, gender, and mortality, there was no significant difference between the two ICUs (p > 0.05). Before the pandemic, the mean length of stay in the ICU was 33.59 ± 32.89 days, and after the pandemic, it was 13.49 ± 8.03 days. This was a statistically significant difference (p < 0.05). Acinetobacter baumannii (28.5%), Klebsiella pneumoniae (22.6%), Pseudomonas aeruginosa (15.9%), Staphylococcus aureus (6.7%), Escherichia coli (7.5%), Candida spp. (5.0%) were the most prevalent causal microorganisms discovered in pre-pandemic ICU ETA samples, whereas A. baumannii (54.0%), K. pneumoniae (10.3%), P. aeruginosa (6.8%), E. faecium (8%), and Candida spp.(13.7%) were the most common causative microorganisms detected in Covid-19 ICU ETA samples. Except for tigecycline, antibiotic resistance rates in A. baumannii strains increased following the pandemic. Only tobramycin showed a significant difference in the increase of resistance among these antibiotics (p = 0.037). The rate of tigecycline resistance, on the other hand, was 17.6% before the pandemic and 2.2% afterward (p < 0.05). After the pandemic, increased resistance of K. pneumoniae strains to colistin, meropenem, ertapenem, amoxicillin-clavulanic acid, piperacillin-tazobactam, ciprofloxacin, tigecycline, and cefepime antibiotics was observed. However, these increases were not statistically significant. Except for imipenem, antibiotic resistance rates in P. aeruginosa strains increased following the pandemic. The increase in resistance of ceftazidime and levofloxacin was statistically significant (p < 0.05). CONCLUSION: As a result, the Covid-19 pandemic requires intensive care follow-ups at an earlier age and with a more mortal course. Although the length of stay in the intensive care unit has been shortened, it is observed that this situation is observed due to early mortality. In P. aeruginosa strains, a significant difference was detected in the resistance increase of the ceftazidime and levofloxacin (p < 0.05) and with the exception of tigecycline, antibiotic resistance rates in A. baumannii strains increased following the pandemic. Only tobramycin showed a significant difference in the increase of resistance among these antibiotics (p = 0.037). Secondary infections in patients create more difficult treatment processes due to both Covid-19 and increasing antibiotic resistance today.

Comparison Of Real-Time Reverse Transcriptase Polymerase Chain Reaction (Rt-Pcr) And Igm And Igg Antibody Test For The Diagnosis Of Sars-Cov-2 Infection

In the present study, we compared the real-time reverse-transcription polymerase chain reaction (RT-PCR) and total IgM-IgG antibody tests for diagnosis SARS-CoV-2 patients. SARS-CoV-2 patients were divided into four additional subgroups according to clinical examination, and Computed Tomography (CT) for SARS-CoV-2. Groups were included 60 mild cases, 111 moderate cases, 53 severe cases, and 105 normal cases. In a mild group, 52.5% of 60 cases were found to be male, 45.9% female, and the average age was found as 38.4 ±2.011. The positive ratio was found as 80.3% in the RT-PCR test, while 39.3% in total IgM/IgG. In a moderate group, 49.1% of 111 cases were found to be male, 50% female, and the average age was 45.05 ±1.519. The positive ratio was found as 85.7% in the RT-PCR test while 54.5% in total IgM/IgG. In a severe group, 53.7%of 53 cases were found to be male, 44.4% female, and the average age was 55.5±2.122. The positive ratio was found as 75.9% both in RT-PCR and total IgM/IgG tests. In a normal group with no involvement according to Computed Tomography (CT), 49.1%of 105 cases were found to be male, 50% female, and the average age was found as 34.8±1.391. The positive ratio was found as 95.3% in the RT-PCR test while 5.7% in total IgM/IgG. Chronic diseases were detected more in severe cases, suggesting that persons who have chronic diseases or decreased immunity, such as diabetes mellitus, cardiovascular diseases, hypertension, and lung disease, are at a higher risk for developing severe COVID-19 if they are infected with SARS-CoV-2. According to our results, we can suggest a higher detection sensibility in RT-PCR than in total IgM/IgG antibody test for mild, moderate and normal group, while the detection sensibility of IgM/IgG antibody increases in a severe group with bilateral diffuse involvement according to CT.