ABSTRACT
Objective: To evaluate the household secondary attack rates of the SARS-CoV-2 Delta variant and the associated factors. Methods: A COVID-19 outbreak caused by the Delta variant occurred in Nanjing in July 2021. A total of 235 cases with current addresses in Nanjing were reported from 171 households. The subjects in this study were selected from household close contact(s) of infected cases. The information on household index cases and their contacts were collected, and the household secondary attack rate (HSAR) and the risk factors were analyzed by the multi-factor logistic regression model. Results: A total of 234 cases of household close contacts and 64 household secondary cases were reported from 103 households, and the HSAR was 27.4% (64/234, 95%CI:22.0% to 33.4%). The proportions of household size for 2 to 3, 4 to 5, and 6 to 9 were 64.1% (66), 26.2% (27) and 9.7% (10), respectively. A total of 35 cases of household cluster outbreaks were reported (35/103, 34.0%). The number of the first case in the household (FCH) was 103 and males accounted for 27.2% (28 cases), with the median age (Q1, Q3) of 49 (9, 56). The number of household close contacts was 234 and males accounted for 59.0% (138 cases), with the median age (Q1, Q3) of 42 (20, 55) and the median exposure period (Q1, Q3) of 3 (1, 3) days. The multi-factor logistic regression model showed that the higher HSAR was observed in the FCH with the features of airport staff (OR=2.913, 95%CI:1.469-5.774), detection from home quarantine screening (OR=6.795, 95%CI:1.761-26.219) and detection from mass screening (OR=4.239, 95%CI:1.098-16.368). Meanwhile, higher HSAR was observed in cases with longer household exposure (OR=1.221, 95%CI:1.040-1.432), non-vaccination (OR=2.963, 95%CI:1.288-6.813) and incomplete vaccinations (OR=2.842, 95%CI:0.925-8.731). Conclusion: The generation interval of the Delta variant is shortened, and the ability of transmission within the household is enhanced. In the outbreak in Nanjing, the associated factors of HSAR are occupation, detection route, vaccination and exposure period.
Subject(s)
Male , Humans , SARS-CoV-2 , COVID-19/epidemiology , Incidence , Family CharacteristicsABSTRACT
<p><b>OBJECTIVE</b>To investigate the effects of YOD1 overexpression on the proliferation and migration of human oral keratinocytes (HOKs), and to clarify whether the mechanisms involve transforming growth factor-β (TGF-β) signaling.</p><p><b>METHODS</b>HOKs were transfected with the plasmid pEGFP-N3-YOD1 containing YOD1. The mRNA levels of YOD1 and TGF-β were determined by qPCR. The protein expressions of YOD1, TGF-β, Smad2/3, Smad4, and phospho-Smad2/3 were determined by western blotting. Cell proliferation and migration were evaluated by Cell Counting Kit-8 assay and wound healing assay, respectively.</p><p><b>RESULTS</b>The mRNA and protein levels of YOD1 were higher in HOKs transfected with YOD1. YOD1 overexpression significantly enhanced the migration of HOKs. The mRNA and protein levels of TGF-β3 were increased by YOD1 overexpression. HOKs transfected with YOD1 exhibited increased phospho-Smad2/3 levels.</p><p><b>CONCLUSION</b>YOD1 overexpression enhances cell migration by promoting TGF-β3 signaling which may play an important role in lip and palate formation. YOD1 mutation may contribute to aberrant TGF-β3 signaling associated with decreased cell migration resulting in NSCLP.</p>
Subject(s)
Humans , Cell Movement , Physiology , Cell Proliferation , Cells, Cultured , Endopeptidases , Genetics , Metabolism , Keratinocytes , Physiology , Signal Transduction , Physiology , Smad Proteins , Genetics , Metabolism , Thiolester Hydrolases , Genetics , Metabolism , Transforming Growth Factor beta3 , Genetics , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To validate the performance of Mycob. T Stainer and Scanner (MTSS) for detecting acid-fast bacilli (AFB).</p><p><b>METHODS</b>A total of 3,816 sputum samples from 1,515 tuberculosis (TB) suspects were tested at the Anhui Provincial Chest Hospital and the Linyi People's Hospital from April-August, 2016. Each specimen was placed on two smear slides. One slide was stained by the ziehl-neelsen (ZN) method to be read by conventional microscopy (CM). The other slide was stained and scanned by MTSS. All specimens were decontaminated with 4% NaOH, and then inoculated into solid culture. The performance of MTSS was assessed.</p><p><b>RESULTS</b>MTSS produced higher average positivity rate (27.96%) as compared with the CM (26.83%). The overall sensitivity and specificity of MTSS were 78.9% and 93.9%, respectively. The sensitivity and specificity of CM was 77.4% and 95.0%, respectively.</p><p><b>CONCLUSION</b>MTSS exhibited a favorable performance in the detection of AFB. It may be an alternative to CM for screening TB.</p>