ABSTRACT
Objectives: SARS-CoV-2 is primarily transmitted within households, with massive healthcare system bur-dens. The role of inactivated vaccines and ChAdOx1 nCoV-19 vaccination in the prevention of within -household transmission remains unknown.Methods: This observational case-control study tracked 408 SARS-CoV-2 polymerase chain reaction- confirmed index cases from April to September 2021. This study aimed to prove the benefit of inactivated and ChAdOx1 nCoV-19 vaccinated index cases in preventing within-household transmissibility.Results: A total of 1178 household contacts were investigated. A total of 231 index cases were vaccinated with inactivated or ChAdOx1 nCoV-19 vaccine, and 177 were unvaccinated. The vaccinated index cases ex-hibited a 7.8% risk reduction in household transmission. There was no difference in the secondary attack rate of 50.77% in unvaccinated cases compared with 46.81% in vaccinated index cases ( P-value = 0.177). Those who completed the two-dose SARS-CoV-2 vaccination demonstrated a 93% reduction in household transmissibility within 14-90 days. The effectiveness for preventing household transmission was 26.09%. The 87% reduced risk of household transmissibility was observed among those who wore masks.Conclusion: The completed two-dose SARS-CoV-2 inactivated and ChAdOx1 nCoV-19 vaccination within 14-90 days among index cases demonstrated benefits in preventing within-household transmissibility. Implementing high-efficacy vaccination and an appropriate booster dose can prevent household trans-mission. (c) 2022 The Author(s). Published by Elsevier Ltd on behalf of International Society for Infectious Diseases. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )
ABSTRACT
Background. The coronavirus disease 2019 (COVID-19) has a wide range of severity. Chest computed tomography (CT) had high sensitivity and specificity to identify COVID-19 pneumonia. However, chest CT was not available in almost all hospitals in pandemic settings, including developed countries. This study is to evaluate the potential role of conventional inflammatory biomarkers to predict COVID-19 pneumonia. Methods. All 155 RT-PCR-confirmed COVID-19 patients were evaluated for pneumonia by chest CT from April 10, 2021 to May 3, 2021 in the outpatient unit, a Thai university hospital. The inflammatory biomarkers were evaluated the sensitivity, specificity, LR+, LR-, and ROC to predict COVID-19 pneumonia. Results. Of all 155 patients, pneumonia was diagnosed by chest CT in 117 patients. The pneumonia patients had a median (IQR) age of 38 (30, 55) years old. The BMI was higher in pneumonia than mild illness in 25.5 (22.0, 29.5) and 22.9 (19.4, 26.9) kg/m2, respectively (p=0.031). In univariate analysis, serum high-sensitivity C-reactive protein (hsCRP), lactate dehydrogenase (LDH), ferritin, total lymphocyte count (TLC), and albumin were associated with pneumonia, but the only hsCRP demonstrated association by multivariate analysis. The area under the ROC curves (AUC) was 0.82, 0.74, 0.68, 0.38, and 0.37 in hsCRP, LDH, ferritin, TLC, and albumin, respectively. The optimal cut-off level for CRP to diagnose COVID-19 pneumonia was 2.00 mg/L given sensitivity, specificity, LR+, LR- of 81.9%, 70.3%, 2.75, and 0.26 respectively (Figure 1 and Table 1). This figure shows ROC curve for hsCRP to diagnose of chest CT-confirmed COVID-19 pneumonia. The area under the ROC curve is 0.82. The optimal cut-off value for hsCRP is 2.00 given sensitivity of 81.9% and specificity of 70.3%. Conclusion. The hsCRP was the conventional biomarker that had an excellent performance in predicting COVID-19 pneumonia lead to early anti-SARS-CoV-2 treatment. This study demonstrated the potential role of hsCRP combined with clinical assessment in negative chest X-rays to replace chest CT in a high burden COVID-19 country during pandemic situations.