Heterologous booster COVID-19 vaccination elicited potent immune responses in HCWs.

The objective of our study was to evaluate the antibody responses of health care workers (HCWs) who were vaccinated with booster dose BNT162b2 6 months after 2 doses of the CoronoVac vaccine. The study included 318 HCWs vaccinated with inactive CoronaVac SARS-CoV-2 vaccine in 2 doses. Anti-spike/RBD IgG levels were measured immediately before and 1 month after the booster dose. In the sixth month after CoronaVac vaccination, the median of antibody levels of 1212.02 AU/ML, while it was 9283 AU/mL after BNT162b2 vaccination. IgG antibody titers of over 1050 AU/mL (which is equivalent to 1:80 dilution in the plaque reduction neutralization test) were detected in HCWs 15.09% and 97.8%, respectively. Our results showed that antibody titers increased 8-fold after the booster dose. We believe that the administration of the mRNA vaccine as a booster dose can provide more effective protection against COVID-19 infection, especially in individuals with risk factors.

Comparison of Hospitalized COVID-19 Patients in Terms of Disease Course According to the Presence of Gastrointestinal Symptoms Before and After Admission.

BACKGROUND: This study aimed to find the prevalence of gastrointestinal symptoms in hospitalized COVID-19 patients and to investigate the effects of gastrointestinal symptoms on the course of the disease during hospitalization. METHODS: Patients who were hospitalized due to COVID-19 were included in this retrospective study. The diagnostic method of COVID-19 was either a positive reverse transcription polymerase chain reaction test or a typical finding in chest computed tomography. This study was conducted by contacting patients by phone 1 month after they were discharged from hospital to investigate gastrointestinal symptoms. Patients' laboratory findings at the time of admission, medications they used, and clinical findings were obtained from hospital records retrospectively. Patients with gastrointestinal symptoms were divided into 2 groups according to the start of treatment: pre-treatment and post-treatment groups. RESULTS: At least 1 gastrointestinal symptom (anorexia, weight loss, diarrhea, nausea, vomiting, and abdominal pain) was present in 67.5% of 435 patients (55.6% male, mean age 52.8). If anorexia and weight loss are excluded, the rate of the presence of at least 1 gastrointestinal symptom is 54%. Gastrointestinal symptoms were present in 48.9% before the initiation of COVID-19 treatment. The most prevalent 3 symptoms were anorexia, weight loss, and diarrhea (56%, 52%, and 35.6%, respectively). Presence of pre-treatment gastrointestinal symptoms was associated with elevated C-reactive protein levels. Pre-treatment gastrointestinal symptoms were more common in those who received oxygen supply and who were intubated. Resolution of gastrointestinal symptoms takes longer time in those who were admitted to intensive care unit. Weight loss and diarrhea were more common in COVID-19 patients with gastrointestinal symptoms who were intubated than who were not intubated. Abdominal pain was not found to be a significant predictor of disease severity. CONCLUSION: The prevalence of at least 1 gastrointestinal symptom in hospitalized COVID-19 patients was 67%. The most prevalent symptoms were anorexia, weight loss, and diarrhea. Presence of pre-treatment gastrointestinal symptoms was associated with elevated C-reactive protein levels, use of oxygen supply, and intubation. Gastrointestinal symptoms persist longer in those admitted to intensive care unit.

Waning immunity to inactive SARS-CoV-2 vaccine in healthcare workers: booster required.

AIMS: Despite high vaccination rates, increasing case numbers continue to be reported with the identification of new variants of concern, and the issue of durability of the vaccine-induced immune response remains hot topic. Real-life data regarding time-dependent immunogenicity of inactivated COVID-19 vaccines are scarce. We aimed to investigate the changes in the antibody at the different times after the second dose of the CoronaVac vaccine. METHODS: The study included 175 HCWs vaccinated with inactive CoronaVac (Sinovac Life Sciences, China) SARS-CoV-2 vaccine in two doses. Anti-spike/RBD IgG levels were measured first, third, and sixth months after the second dose. Chemiluminescent microparticle immunoassay (IgG II Quant test, Abbott, USA), which is 100% compatible with plaque reduction neutralization test, was used. RESULTS: Mean age of the participants was 38 ± 11.23 years (range between 22 and 66) of whom 119 (63.9%) were female, and 56 (32%) were male. Dramatic reductions were demonstrated in median antibody levels particularly in the infection-naïve group, comprising 138 HCWs compared to those with prior history of COVID-19 infection (n = 37) (p < 0.001). There was no difference between the two groups in terms of age, gender, blood groups, BMI, and comorbid diseases. CONCLUSIONS: While antibody positivity remained above 90% in the 6th month after two doses of inactivated vaccine in HCWs, the median titers of neutralizing antibodies decreased rapidly. The decrease was more rapid and significant in those with no history of prior COVID-19 infection. In this critical phase of the pandemic, where we are facing the dominance of the Omicron variant after Delta, booster doses have become vital.

Association of SARS-CoV-2 IgG Antibody Levels with Clinical/Laboratory Characteristics in COVID-19 Patients: Data from a Turkish Study.

BACKGROUND: COVID-19 causes clinical manifestations ranging from asymptomatic infection to multi-organ failure. It is reported that those with severe disease have higher anti-SARS-CoV-2 antibody titers compared to asymptomatic or mild cases. We evaluated the correlation of antibody responses with laboratory and clinical indicators in COVID-19 patients. METHODS: Seventy-nine male and 66 female patients (mean age: 39) with at least one positive SARS-CoV-2 RT-PCR test and SARS-CoV-2 IgG antibody result after acute infection were included. RESULTS: Seventy-six (52%), 45 (31%), and 24 (17%) patients had mild, moderate, and severe clinical findings, respectively. Patients with high body mass index and advanced age had significantly more severe disease (p < 0.001). A significant correlation was found between the increase in lymphopenia, C-reactive protein, ferritin, D-dimer, and lactate dehydrogenase and the severity of clinical findings (p = 0.0001). SARS-CoV-2 IgG antibody test was positive in 128 (88.3%) patients. A significant correlation was found between disease severity and antibody levels in the comparison of all groups (p < 0.001). CONCLUSIONS: Long-term monitoring of immune responses will be required to determine the appropriate time for the administration of new vaccines.

Incidence, Risk Factors, and Prognosis of Bloodstream Infections in COVID-19 Patients in Intensive Care: A Single-Center Observational Study.

BACKGROUND: Critically ill COVID-19 patients are prone to bloodstream infections (BSIs). AIM: To evaluate the incidence, risk factors, and prognosis of BSIs developing in COVID-19 patients in the intensive care unit (ICU). METHODS: Patients staying at least 48 h in ICU from 22 March 2020 to 25 May 2021 were included. Demographic, clinical, and laboratory data were analyzed. RESULTS: The median age of the sample (n = 470) was 66 years (IQR 56.0-76.0), and 64% were male. The three most common comorbidities were hypertension (49.8%), diabetes mellitus (32.8%), and coronary artery disease (25.7%). Further, 252 BSI episodes developed in 179 patients, and the BSI incidence rate was 50.2 (95% CI 44.3-56.7) per 1000 patient-days. The source of BSI is central venous catheter in 42.5% and lower respiratory tract in 38.9% of the episodes. Acinetobacter baumannii (40%) and carbapenem-resistant Klebsiella pneumoniae (21%) were the most common pathogens. CRP levels were lower in patients receiving tocilizumab. Multivariable analysis revealed that continuous renal replacement therapy, extracorporeal membrane oxygenation, and treatment with a combination of methylprednisolone and tocilizumab were independent risk factors for BSI. The estimated cumulative risk of developing first BSI episode was 50% after 6 days and 100% after 25 days. Of the 179 patients, 149 (83.2%) died, and a statistically significant difference (p < 0.001) was found in the survival distribution in favor of the group without BSI. CONCLUSION: BSI is a common complication in COVID-19 patients followed in the ICU, and it can lead to mortality. Failure in infection control measures, intensive immunosuppressive treatments, and invasive interventions are among the main factors leading to BSIs.

A pan-resistant Myroides odoratimimus catheter-related bacteremia in a COVID-19 patient and review of the literature.

Myroides spp. are opportunistic environmental Gram-negative bacteria. These affect mostly immunocompromised hosts and generally lead to soft tissue, and urinary tract infections. Bacteremia most commonly develop secondary to soft tissue or catheter related infections and may lead rarely to mortality. Myroides spp. are generally suscetible to fluoroquinolones, piperacillin/tazobactam, trimethoprim/sulfamethoxazole, carbapenems or tetracyclines however, pan-resistant isolates and multiple resistance genes have been reported in clinical isolates of Myroides spp. We report a pan-resistant Myroides odoratimimus bacteremia in a patient with severe COVID-19 ending with fatality and in this context a review of reported Myroides bacteremias are also described. In this study, a 64-year old male patient with history of coronary artery bypass was admitted to ICU with severe COVID-19 pneumonia accompanied by pneumomediastinum and pneumopericardium. Continous renal replacement therapy and extracorporeal membraneous-oxygenation were initiated due to acute renal failure and persistent hypercarbia/hypoxia, respectively. Within four weeks of hospitalization various episodes of bacteremia developed and multiple antibiotics were used. On the 5th week of follow-up, acute phase reactants increased and empirical broad spectrum antibiotics were initiated. Blood culture revealed Gram-negative rods. The patient became hypotensive and despite maximum medical care he was lost due to cardiac arrest. M. odoratimimus was identified by MALDI-TOF and the bacterium was pan-resistant. According to Center for Genomic Epidemiology results the strain was identified as M. odoratimimus PR63039 and the genome analysis revealed antibiotic resistance genes associated with resistance to beta-lactams (bla OXA-347, bla MUS-1, bla EBR-1), tetracyclines (tetX), sulfonamides (sul2), macrolides (ereD), (ermF).

Detection of SARS-CoV-2 RNA in Upper Respiratory Swap Samples by Pooling Method

Background: Widespread and effective use of molecular diagnostic tests is indispensable for protecting public health and containing the severe respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. More than 1 year into the pandemic, as resources have reached a point of depletion, grouping samples in pools of certain sizes appears to be a reasonable method to reduce both the costs and the processing time without necessitating additional training, equipment, or materials. Aims: To assess whether the pooling strategy that was used in past outbreaks and is used in blood tests prior to transfusion for screening large populations can also be used in SARS CoV-2 tests. Study Design: Diagnostic accuracy study. Methods: This prospective study was conducted with 2815 samples, sent to the coronavirus disease 2019 (COVID-19) Laboratory of our hospital between February 12 and 21, 2021, to be tested for the presence of SARS-CoV-2. The samples were examined individually and in pools of five 100 µl taken from each sequential sample, using 3 different SARS-CoV-2 reverse transcription-polymerase chain reaction (RT-PCR) kits, the Allplex™ 2019-nCoV Assay kit (Seegene, Republic of Korea), the GeneMAP™ 2019-nCoV detection V.3 kit (GenMark, Türkiye), and the Bio-Speedy™ SARS-CoV-2 Double Gene™ RT-qPCR kit (Bioeksen, Türkiye) on the BioRAD CFX96™ Touch (Bio-Rad Laboratories Inc., Hercules, CA, USA) platform available in our laboratory. Results: Following the extraction of serial dilutions prepared from the SARS-CoV-2 RNA positive (cycle of threshold: 20) sample, the standard curves of RT-PCR were analyzed. By evaluating the efficiency (E) values, all 3 kits showed high sensitivity and similar results; while the highest level was detected with the Allplex™ 2019-nCoV Assay kit in the nucleocapsid (N) gene (E: 124%), the lowest was detected with the Double Gene™ RT-qPCR kit in the N and ORF 1ab genes (E: 90%). Of the samples included in the study, only 1 positive sample with low viral load was found to be negative when studied by pooling. The total number of kits to be used in pooled tests and then to individually retest the 5 samples in positive pools was calculated as 827 and the savings rate as 69.91% (1968/2815). Conclusion: The pooling strategy is an effective approach to extend the impact of limited testing resources and reagents available in certain periods of the COVID-19 pandemic. Testing by pooling samples requires improvement of RNA extraction methods and careful monitoring of RT-PCR test sensitivity to avoid missing low-positive entities. Therefore, based on the prevalence of COVID-19 in their regions, laboratories should conduct their own validation of pooling studies for RNA extraction and amplification methods they use.

Inactive SARS-CoV-2 vaccine generates high antibody responses in healthcare workers with and without prior infection.

BACKGROUND AND OBJECTIVES: Healthcare workers (HCWs) were among the first groups to be vaccinated in Turkey. The data to be obtained by the vaccination of HCWs would guide wide spread vaccination programs. MATERIALS AND METHODS: The study included 330 HCWs working at Istanbul University-Cerrahpasa, Cerrahpasa Medical Faculty Hospital and vaccinated with inactive CoronaVac (Sinovac Life Sciences, China) SARS-CoV-2 vaccine in two doses (28 days apart). Anti-Spike /RBD IgG levels were measured 14 days after the first dose and 28 days after the second dose. Chemiluminescent microparticle immunoassay (CMIA) (ARCHITECT IgG II Quant test, Abbott, USA), which is 100% compatible with plaque reduction neutralization test (PRNT), was used. RESULTS: Of the participants, 211 (63.9%) were female, 119 (36.1%) were male, and mean age was 39.6 ± 7.7 years. In those without prior COVID-19 history; (n = 255) antibody positivity was detected as 48.2% (95% CI: 42.1-54.3) 14 days after the first dose of vaccine, and 99.2% (95% CI: 98.1-100) at day 28 after the second dose. Antibody titers were significantly lower in patients with hypertension (p = 0.011). In those with prior history of COVID-19 (n = 75); both the antibody positivity rates after the first vaccine (48.2% vs 100%, p = 0.000) and the anti-spike/RBD antibody levels after the second vaccine (with a ≥ 1050 AU/mL titer equivalent to PRNT 1/80 dilution) was significant than infection-naive group (25.9% vs. 54.7%, p = 0.000). Antibody positivity after two doses of vaccination for all study group was 99.4% (95% CI: 98.6-100). CONCLUSIONS: Two doses CoronaVac produce effective humoral immunity in HCWs. Antibody response is significantly higher in those with prior history of COVID-19 than infection-naive group. Given no significant benefit of the second dose, a single shot of vaccination may be sufficient for those with prior history of COVID-19. Monitoring humoral and cellular immune responses, considering new variants, is required to validate this approach.

COVID-19 and Plasmodium ovale Malaria: A Rare Case of Co-Infection.

The COVID-19 pandemic continues to be a major health problem worldwide. Timely diagnosis of co-infections mimicking COVID-19, such as malaria, might be challenging particularly in non-endemic areas. We report the first case of COVID-19 and Plasmodium ovale malaria co-infection from our region aiming to highligt the importance of travel history and prophylaxis in malaria management in the context of pandemic. The galloping sound can sometimes be a harbinger of zebra besides the horse.

Tocilizumab in COVID-19: The Cerrahpasa-PREDICT score.

BACKGROUND: Cytokine release syndrome (CRS), characterized by overproduction of proinflammatory cytokines in the course of severe coronavirus disease 2019 (COVID-19), has been suggested as the major cause of mortality. Tocilizumab, a recombinant humanized monoclonal antibody against human IL-6 receptor, poses a therapeutic option for the treatment of CRS leading to severe acute respiratory syndrome in coronavirus-2 (SARS-CoV-2) infection. METHODS: We performed a single-center retrospective study to reveal the outcome of COVID-19 patients on tocilizumab and proposed "the Cerrahpasa-PREDICT score", a new clinical scoring system using clinical and laboratory parameters that would help predicting the 28-day mortality of COVID-19 patients receiving tocilizumab. RESULTS: Eighty-seven patients (median age: 59 years) were included of whom 75.8% were male. Tocilizumab use significantly improved clinical and laboratory parameters. The 28-day mortality rate on tocilizumab was 16.1%. The Cerrahpasa-PREDICT score, consisting of platelet counts, procalcitonin, D-dimer levels, SO2R and the time from symptom onset to tocilizumab administration had a positive predictive value of 94.5% and negative predictive value of 92.9% for anticipating 28-day mortality. CONCLUSIONS: Severe COVID-19 should closely be monitored for the signs of hyperinflammation. We showed that administration of tocilizumab early in the course of the disease (prior to ICU admission) resulted in a favorable outcome. Close monitoring usually aids identifying patients who would benefit from tocilizumab. In this regard, the Cerrahpasa-PREDICT score might serve as a practical tool for estimating the 28-day mortality in COVID-19 patients who received tocilizumab and would facilitate timely recognition of fatal cases to be evaluated for other therapeutic options.

Kidney function on admission predicts in-hospital mortality in COVID-19.

BACKGROUND: Recent data have suggested the presence of a reciprocal relationship between COVID-19 and kidney function. To date, most studies have focused on the effect of COVID-19 on kidney function, whereas data regarding kidney function on the COVID-19 prognosis is scarce. Therefore, in this study, we aimed to investigate the association between eGFR on admission and the mortality rate of COVID-19. METHODS: We recruited 336 adult consecutive patients (male: 57.1%, mean age: 55.0±16.0 years) that were hospitalized with the diagnosis of COVID-19 in a tertiary care university hospital. Data were collected from the electronic health records of the hospital. On admission, eGFR was calculated using the CKD-EPI formula. Acute kidney injury was defined according to the KDIGO criteria. Binary logistic regression and Cox regression analyses were used to assess the relationship between eGFR on admission and in-hospital mortality of COVID-19. RESULTS: Baseline eGFR was under 60 mL/min/1.73m2 in 61 patients (18.2%). Acute kidney injury occurred in 29.2% of the patients. In-hospital mortality rate was calculated as 12.8%. Age-adjusted and multivariate logistic regression analysis (p: 0.005, odds ratio: 0.974, CI: 0.956-0.992) showed that baseline eGFR was independently associated with mortality. Additionally, age-adjusted Cox regression analysis revealed a higher mortality rate in patients with an eGFR under 60 mL/min/1.73m2. CONCLUSIONS: On admission eGFR seems to be a prognostic marker for mortality in patients with COVID-19. We recommend that eGFR be measured in all patients on admission and used as an additional tool for risk stratification. Close follow-up should be warranted in patients with a reduced eGFR.