Effectiveness of two coronavirus disease 2019 (COVID-19) vaccines (viral vector and inactivated viral vaccine) against severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection in a cohort of healthcare workers.

OBJECTIVE: We investigated real-world vaccine effectiveness for Oxford-AstraZeneca (ChAdOx1) and CoronaVac against laboratory-confirmed severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection among healthcare workers (HCWs). METHODS: We conducted a retrospective cohort study among HCWs (aged ≥18 years) working in a private healthcare system in Brazil between January 1, 2021 and August 3, 2021, to assess vaccine effectiveness. We calculated vaccine effectiveness as 1 - rate ratio (RR), with RR determined by adjusting Poisson models with the occurrence of SARS-CoV-2 infection as the outcome and the vaccination status as the main variable. We used the logarithmic link function and simple models adjusting for sex, age, and job types. RESULTS: In total, 13,813 HCWs met the inclusion criteria for this analysis. Among them, 6,385 (46.2%) received the CoronaVac vaccine, 5,916 (42.8%) received the ChAdOx1 vaccine, and 1,512 (11.0%) were not vaccinated. Overall, COVID-19 occurred in 6% of unvaccinated HCWs, 3% of HCWs who received 2 doses of CoronaVac vaccine, and 0.7% of HCWs who received 2 doses of ChAdOx1 vaccine (P < .001). In the adjusted analyses, the estimated vaccine effectiveness rates were 51.3% for CoronaVac, and 88.1% for ChAdOx1 vaccine. Both vaccines reduced the number of hospitalizations, the length of hospital stay, and the need for mechanical ventilation. In addition, 19 SARS-CoV-2 samples from 19 HCWs were screened for mutations of interest. Of 19 samples, 18 were the γ (gamma) variant. CONCLUSIONS: Although both COVID-19 vaccines (viral vector and inactivated virus) can significantly prevent COVID-19 among HCWs, CoronaVac was much less effective. The COVID-19 vaccines were also effective against the dominant γ variant.

Effectiveness of Heterologous Coronavirus Disease 2019 (COVID-19) Vaccine Booster Dosing in Brazilian Healthcare Workers, 2021.

BACKGROUND: Little is currently known about vaccine effectiveness (VE) for either 2 doses of Oxford-AstraZeneca (ChAdOx1) viral vector vaccine or CoronaVac (Instituto Butantan) inactivated viral vaccine followed by a third dose of mRNA vaccine (Pfizer/BioNTech) among healthcare workers (HCWs). METHODS: We conducted a retrospective cohort study among HCWs (aged ≥18 years) working in a private healthcare system in Brazil from January to December 2021. VE was defined as 1 - incidence rate ratio (IRR), with IRR determined using Poisson models with the occurrence of laboratory-confirmed coronavirus disease 2019 (COVID-19) infection as the outcome, adjusting for age, sex, and job type. We compared those receiving viral vector or inactivated viral primary series (2 doses) with those who received an mRNA booster. RESULTS: A total of 11 427 HCWs met the inclusion criteria. COVID-19 was confirmed in 31.5% of HCWs receiving 2 doses of CoronaVac vaccine versus 0.9% of HCWs receiving 2 doses of CoronaVac vaccine with mRNA booster (P < .001) and 9.8% of HCWs receiving 2 doses of ChAdOx1 vaccine versus 1% among HCWs receiving 2 doses of ChAdOx1 vaccine with mRNA booster (P < .001). In the adjusted analyses, the estimated VE was 92.0% for 2 CoronaVac vaccines plus mRNA booster and 60.2% for 2 ChAdOx1 vaccines plus mRNA booster, when compared with those with no mRNA booster. Of 246 samples screened for mutations, 191 (77.6%) were Delta variants. CONCLUSIONS: While 2 doses of ChAdOx1 or CoronaVac vaccines prevent COVID-19, the addition of a Pfizer/BioNTech booster provided significantly more protection.

Percutaneous Cryoablation versus Robot-Assisted Partial Nephrectomy of Renal T1A Tumors: a Single-Center Retrospective Cost-Effectiveness Analysis.

PURPOSE: To evaluate the cost-effectiveness of percutaneous cryoablation (PCA) versus robot-assisted partial nephrectomy (RPN) in patients with small renal tumors (T1a stage), considering perioperative complications. MATERIALS AND METHODS: Retrospective study from November 2008 to April 2017 of 122 patients with a T1a renal mass who after being analyzed by a multidisciplinary board underwent to PCA (59 patients) or RPN (63 patients). Hospital costs in US dollars, and clinical and tumor data were compared. Non-complicated intervention was considered as an effective outcome. A hypothetical model of possible complications based on Clavien-Dindo classification (CDC) was built, grouping them into mild (CDC I and II) and severe (CDC III and IV). A decision tree model was structured from complications of published data. RESULTS: Patients who underwent PCA were older (62.5 vs. 52.8 years old, p < 0.001), presented with more coronary disease and previous renal cancer (25.4% vs. 10.1%, p = 0.023 and 38% vs. 7.2%, p < 0.001, respectively). Patients treated with PCA had a higher preoperative risk (American Society of Anesthesiologists-ASA ≥ 3) than those in the RPN group (25.4% vs. 0%, p < 0.001). Average operative time was significantly lower with PCA than RPN (99.92 ± 29.05 min vs. 129.28 ± 54.85 min, p < 0.001). Average hospitalization time for PCA was 2.2 ± 2.95 days, significantly lower than RPN (mean 3.03 ± 1.49 days, p = 0.04). The average total cost of PCA was significantly lower than RPN (US$12,435 ± 6,176 vs. US$19,399 ± 6,047, p < 0.001). The incremental effectiveness was 5% higher comparing PCA with RPN, resulting a cost-saving result in favor of PCA. CONCLUSION: PCA was the dominant strategy (less costly and more effective) compared to RPN, considering occurrence of perioperative complications.