Background: Since December 2019, the coronavirus disease 2019 (COVID-19) has infected more than 12,310322,000 people and killed over 556,000 people worldwide. However, Differential diagnosis remains di cult for suspected cases of COVID-19 and need to be improved to reduce misdiagnosis. Methods: Sixty-eight cases of suspected COVID-19 treated in Wenzhou Central Hospital from January 21 to February 20, 2020 were divided into con rmed and COVID-19-negative groups based on the results of real-time reverse transcriptase polymerase chain reaction (RT-PCR) nucleic acid testing of the novel coronavirus in throat swab specimens to compare the clinical symptoms and laboratory and imaging results between the groups. Results: Among suspected patients, 17 were con rmed to COVID-19-positive group and 51 were distinguished to COVID-19-negative group. Patients with reduced white blood cell (WBC) count were more common in the COVID-19-positive group than in the COVID-19-negative group (29.4% vs 3.9%, P = 0.003). Subsequently, correlation analysis indicated that there was a signi cant inverse correlation existed between WBC count and temperature in the COVID-19-positive patients (r=-0.587, P=0.003), instead of the COVID-19-negative group. But reduced lymphocyte count was no different between the two groups (47.1% vs 25.5%, P= 0.096). More common chest imaging characteristics of the con rmed COVID-19 cases by high-resolution computed tomography (HRCT) included ground-glass opacities (GGOs), multiple patchy shadows, and consolidation with bilateral involvement than COVID-19-negative group (82.4% vs 31.4%, P=0.0002; 41.2% vs 17.6% vs P=0.048; 76.5% vs 43.1%, P=0.017; respectively). The rate of clustered infection was higher in COVID-19-positive group than COVID-19-negative group (64.7% vs 7.8%, P=0.001). Through multiplex PCR nucleic acid testing, 2 cases of in uenza A, 3 cases of in uenza B, 2 cases of adenovirus, 2 cases of Chlamydia pneumonia, and 7 cases of Mycoplasma pneumoniae were diagnosed in the COVID-19-negative group. Conclusions: WBC count inversely correlated with the severity of fever, GGOs, multiple patchy shadows, and consolidation in chest HRCT and clustered infection are common but not speci c features in the con rmed COVID-19 group.Reduced WBC count inversely correlating with the severity of fever, GGOs, multiple patchy shadows, and consolidation in chest HRCT and clustered infection are features in the con rmed COVID-19 group but not unique. Multiplex PCR nucleic acid testing helped differential diagnosis for suspected COVID-19 casesexclude pathogenic diagnosis in COVID-19 patients. Background Since December 2019, the epidemic of pneumonia caused by novel coronavirus in China, has continued to progress [1], having now infected more than 12,322,000 people and killed over 556,000 people worldwide [2]. On February 11, 2020, The International Committee on Taxonomy of Viruses o cially named this severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the World Health Organization (WHO) named the disease corona...

SARS-CoV-2-specific antibodies, particularly those preventing viral spike receptor binding domain (RBD) interaction with host angiotensin-converting enzyme 2 (ACE2) receptor, can neutralize the virus. It is, however, unknown which features of the serological response may affect clinical outcomes of COVID-19 patients. We analyzed 983 longitudinal plasma samples from 79 hospitalized COVID-19 patients and 175 SARS-CoV-2-infected outpatients and asymptomatic individuals. Within this cohort, 25 patients died of their illness. Higher ratios of IgG antibodies targeting S1 or RBD domains of spike compared to nucleocapsid antigen were seen in outpatients who had mild illness versus severely ill patients. Plasma antibody increases correlated with decreases in viral RNAemia, but antibody responses in acute illness were insufficient to predict inpatient outcomes. Pseudovirus neutralization assays and a scalable ELISA measuring antibodies blocking RBD-ACE2 interaction were well correlated with patient IgG titers to RBD. Outpatient and asymptomatic individuals’ SARS-CoV-2 antibodies, including IgG, progressively decreased during observation up to five months post-infection.

SUMMARY Norovirus, an RNA virus of the family Caliciviridae , is a human enteric pathogen that causes substantial morbidity across both health care and community settings. Several factors enhance the transmissibility of norovirus, including the small inoculum required to produce infection (<100 viral particles), prolonged viral shedding, and its ability to survive in the environment. In this review, we describe the basic virology and immunology of noroviruses, the clinical disease resulting from infection and its diagnosis and management, as well as host and pathogen factors that complicate vaccine development. Additionally, we discuss overall epidemiology, infection control strategies, and global reporting efforts aimed at controlling this worldwide cause of acute gastroenteritis. Prompt implementation of infection control measures remains the mainstay of norovirus outbreak management.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections can cause Coronavirus Disease 2019 (COVID-19), which manifests with a range of severities from mild illness to life threatening pneumonia and multi-organ failure. Severe COVID-19 is characterized by an inflammatory signature including high levels of inflammatory cytokines, alveolar inflammatory infiltrates and vascular microthrombi. Here we show that severe COVID-19 patients produced a unique serologic signature, including increased IgG1 with afucosylated Fc glycans. This Fc modification on SARS-CoV-2 IgGs enhanced interactions with the activating FcγR, FcγRIIIa; when incorporated into immune complexes, Fc afucosylation enhanced production of inflammatory cytokines by monocytes, including IL-6 and TNF. These results show that disease severity in COVID-19 correlates with the presence of afucosylated IgG1, a pro-inflammatory IgG Fc modification.

This study describes findings of novel coronavirus testing on pooled nasopharyngeal and bronchoalveolar lavage samples taken from patients who had negative results by routine respiratory virus testing to see if pooling samples could increase testing throughput and efficiency and facilitate early detection of community COVID-19 transmission.