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The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had highly transmissible and pathogenic, which caused serious economic loss and hazard to public health. Different countries have developed strategies to deal with the COVID-19 pandemic that fit their epidemiological situations, capacities, and values. Mass screening combined with control measures rapidly reduced the transmission of the SARS-CoV-2 infection. The COVID-19 pandemic has dramatically highlighted the essential role of diagnostics capacity in the control of communicable diseases. Mass screening has been increasingly used to detect suspected COVID-19 cases and their close contacts, asymptomatic case, patients attending fever clinics, high-risk populations, employees, even all population to identify infectious individuals. Mass screening is a key component to fight against SARS-CoV-2 and return to normalcy. Here we describe the history of mass screening, define the scope of mass screening, describe its application scenarios, and discuss the impact and challenges of using this approach to control COVID-19. We conclude that through a comprehension screening program and strong testing capabilities, mass screening could help us return to normalcy more quickly.

Coxsackievirus A16 (CV‐A16) is a significant etiologic agent of hand, foot, and mouth disease (HFMD) and herpangina (HA), with the capacity to progress to severe complications, including encephalitis, aseptic meningitis, acute flaccid paralysis, myocarditis, and other critical conditions. Beijing's epidemiological surveillance system, established in 2008, encompasses 29 hospitals and 16 district disease control centers. From 2019 to 2021, the circulation of CV‐A16 was characterized by the co‐circulation of B1a and B1b clades. Multiple cases of HFMD linked to clade B1c has not been reported in Beijing until 2022. This study enrolled 400 HFMD and 493 HA cases. Employing real‐time RT‐PCR, 368 enterovirus‐positive cases were identified, with 180 selected for sequencing. CV‐A16 was detected in 18.89% (34/180) of the cases, second only to CV‐A6, identified in 63.33% (114/180). Full‐length VP1 gene sequences were successfully amplified and sequenced in 22 cases, revealing the presence of clades B1a, B1b, and B1c in 14, 3, and 5 cases, respectively. A cluster of five B1c clade cases occurred between June 29 and July 17, 2022, within a 7‐km diameter region in Shunyi District. Phylogenetic analysis of five complete VP1 gene sequences and two full‐genome sequences revealed close clustering with the 2018 Indian strain (GenBank accession: MH780757.1) within the B1c India branch, with NCBI BLAST results showing over 98% similarity. Comparative sequence analysis identified three unique amino acid variations (P3S, V25A, and I235V). The 2022 Shunyi District HFMD cases represent the first instances of spatiotemporally correlated CV‐A16 B1c clade infections in Beijing, underscoring the necessity for heightened surveillance of B1c clade CV‐A16 in HFMD and HA in this region. [ABSTRACT FROM AUTHOR]

SARS‐CoV‐2 is still spreading globally. Studies have reported the stability of SARS‐CoV‐2 in aerosols and on surfaces under different conditions. However, studies on the stability of SARS‐CoV‐2 and viral nucleic acids on common food and packaging material surfaces are insufficient. The study evaluated the stability of SARS‐CoV‐2 using TCID50 assays and the persistence of SARS‐CoV‐2 nucleic acids using droplet digital polymerase chain reaction on various food and packaging material surfaces. Viral nucleic acids were stable on food and material surfaces under different conditions. The viability of SARS‐CoV‐2 varied among different surfaces. SARS‐CoV‐2 was inactivated on most food and packaging material surfaces within 1 day at room temperature but was more stable at lower temperatures. Viruses survived for at least 1 week on pork and plastic at 4°C, while no viable viruses were detected on hairtail, orange, or carton after 3 days. There were viable viruses and a slight titer decrease after 8 weeks on pork and plastic, but titers decreased rapidly on hairtail and carton at –20°C. These results highlight the need for targeted preventive and disinfection measures based on different types of foods, packaging materials, and environmental conditions, particularly in the cold‐chain food trade, to combat the ongoing pandemic. [ABSTRACT FROM AUTHOR]

Introduction: Highly fluoroquinolone-resistant Salmonella enterica serovar Kentucky ( S. Kentucky) of sequence type (ST) 198 has emerged as a global multidrug-resistant (MDR) clone, posing a threat to public health., Methods: Whole genome sequencing and antibiotic susceptibility testing was used to characterize the population structure and evolutionary history of 54 S. Kentucky isolates recovered from food and human clinical cases in Beijing from 2016 to 2023., Results: All 54 S. Kentucky ST198 isolates exhibited resistance to quinolones, carrying point mutations in the quinolone resistance-determining regions ( gyrA _S83F and parC _S80I). Resistance to other antibiotics (folate pathway inhibitors, cephems, aminoglycosides, phenicols, rifamycin, fosfomycin, macrolides, and tetracyclines), mediated by the sul1 , sul2 , dfrA14 , bla CTX-M , bla TEM-1B , aac(3)-Id , aadA2 , aadA7 , aph(3')-I , aph(3'')-Ib , rmtB , floR , arr-2 , fosA , mph(A) , and tet(A) genes, was also observed in different combinations. The Beijing S. Kentucky ST198 evolutionary tree was divided into clades 198.2-1 and 198.2-2, which were further differentiated into three subclades: 198.2-2A, 198.2-2B, and 198.2-2C. Compared with the extended-spectrum β-lactamase-encoding gene bla CTX-M-14b in 198.2-1, the co-existence of bla CTX-M-55 and bla TEM-1B , as well as chromosomally located qnrS1 , was detected in most 198.2-2 isolates, which showed more complex MDR phenotypes. S. Kentucky ST198 outbreak isolates derived from two predominant clonal sources: 198.2-1 with cgST236434 and 198.2-2A with cgST296405., Conclusions: The S. Kentucky population in Beijing is genetically diverse, consisting of multiple co-circulating lineages that have persisted since 2016. Strengthening surveillance of food and humans will aid in implementing measures to prevent and control the spread of AMR., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2024.)

What Is Already Known About This Topic?: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to evolve, the clinical manifestations resulting from different SARS-CoV-2 variants may demonstrate significant variation., What Is Added by This Report?: We conducted a comparative analysis of the clinical features associated with SARS-CoV-2 Omicron subvariants BF.7.14 and BA.5.2.48 infections. The results of our study indicate that there are no substantial differences in clinical manifestations, duration of illness, healthcare-seeking behaviors, or treatment between these two subvariants., What Are the Implications for Public Health Practice?: Timely identification of alterations in the clinical spectrum is crucial for researchers and healthcare practitioners in order to enhance their comprehension of clinical manifestations, as well as the progression of SARS-CoV-2. Furthermore, this information is beneficial for policymakers in the process of revising and implementing appropriate countermeasures., Competing Interests: No conflicts of interest., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2023.)

Introduction: In November 2021, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant was identified as the variant of concern and has since spread globally, replacing other cocirculating variants. To better understand the dynamic changes in viral load over time and the natural history of the virus infection, we analyzed the expression of the open reading frames 1ab (ORF1ab) and nucleocapsid (N) genes in patients infected with Omicron., Methods: We included patients initially admitted to the hospital for SARS-CoV-2 infection between November 5 and December 25, 2022. We collected daily oropharyngeal swabs for quantitative reverse transcriptase-polymerase chain reaction tests using commercial kits. We depicted the cycle threshold (Ct) values for amplification of ORF1ab and N genes from individual patients in age-specific groups in a time series., Results: A total of 480 inpatients were included in the study, with a median age of 59 years (interquartile range, 42 to 78; range, 16 to 106). In the <45-year-old age group, the Ct values for ORF1ab and N gene amplification remained below 35 for 9.0 and 11.5 days, respectively. In the ≥80-year-old age group, the Ct values for ORF1ab and N genes stayed below 35 for 11.5 and 15.0 days, respectively, which was the longest among all age groups. The Ct values for N gene amplification took longer to rise above 35 than those for ORF1ab gene amplification., Conclusion: The time to test negative varied among different age groups, with viral nucleic acid shedding taking longer in older age groups compared to younger age groups. As a result, the time to resolution of Omicron infection increased with increasing age., Competing Interests: No conflicts of interest., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2023.)

Competing Interests: Conflicts of interest: No conflicts of interest.

Digital polymerase chain reaction (dPCR) is a new method for absolute quantification. However, an absolute quantification method for influenza A viruses based on droplet digital polymerase chain reaction (dPCR) has not been established. In this study, we found that: (i) the annealing temperature of dPCR was optimized at 64, 4°C; (ii) the detection range of dPCR was 37.7 approximately 8.22 X 10(4) copies/μl for influenza A viruses; (iii) the limit of detection of dPCR was 3. 77 copies/reaction. The liner correlation coefficient (R(2)) was found to be 0. 9988, suggesting the high reliability of our dPCR method. The dPCR method could be used to detect influenza A viruses clinically. In summary, we developed a dPCR method for absolute quantification of influenza A viruses. This method could be used effectively to quantify influenza A viruses in clinical samples. Therefore, our method could be a new tool for the absolute quantification of viral load.

Digital polymerase chain reaction (dPCR) is a new method for absolute quantification of nucleic acids. The dPCR reaction solution is divided into numerous partitions followed by independent amplification. Target copy number is counted using statistical analyses of positive signals. in contrast to quantitative PCR, a standard curve is not necessary for dPCR. Here, we reviewed the development, principles, and applications of dPCR.