Comparison of the clinical characteristics between 37 adults and 10 children with COVID-19. (Special Issue: Spatio-temporal dynamics analysis, risk assessment and emergency management for COVID-19 epidemic.) [Chinese]

Objective: To explore the differences in clinical characteristics between children and adults with COVID-19. Methods The epidemiological characteristics, clinical symptoms, laboratory results, imaging results and treatment regimens of 37 adult and 10 children cases of COVID-19 were analyzed. Results Family clusters were more common in the adult group, while all children cases were caused by intra-family transmission. The adult group had a significantly higher incidence of symptoms such as fever, cough, pharyngeal pain(pharyngeal itch)and fatigue(muscle soreness)than the children group(P < 0.05), while there is no difference in symptoms like chest tightness and chest pain. The children group had a higher rate of non-changing pulmonary imaging than the adult group(P < 0.05). The children group had higher increase of myocardial enzyme than the adult group(P < 0.05), while there were no differences in the increases of liver enzyme, myoglobin and troponin. The children group had lower increase of CRP, IL-6 and SAA than the adult group(P < 0.05), while there were no significant differences in the increase of PCT and decreases of leukocyte and lymphocyte counts. The treatment regimen for the children group was simpler than that for the adults. Conclusion Intra-family transmission is the main way for children to catch COVID-19. Compared with adults, children have milder clinical symptoms, milder CT lesions, no obvious liver and myocardial damage, and no significant changes in inflammatory indicators.

Dynamic profiles of SARS-Cov-2 infection from five Chinese family clusters in the early stage of the COVID-19 pandemic.

Although several cases of family clusters with SARS-Cov-2 infection have been reported, there are still limited data preventing conclusions from being drawn regarding the characteristics and laboratory findings in the COVID-19 population within family clusters. In the present study, we retrospectively collected five family clusters with COVID-19 and summarized the dynamic profiles of the clinical characteristics, laboratory findings, immune markers, treatment and prognosis of this population. Furthermore, we also compared clinical and laboratory data between the SARS-Cov-2 infection with family cluster (n = 21) and those without family cluster (n = 16). We demonstrated that the duration of SARS-Cov-2 replication might be varied based on the different family clusters due to their different genetic backgrounds. The onset improved lung radiology might start at the end of the SARS-Cov-2 positive period. Furthermore, the obtained results demonstrated that similar basic characteristics and clinical findings seem to exist between the cases with SARS-Cov-2 and without family clusters. The serum level of ferritin might have a different biological function and be a new biomarker for the family cluster. Further studies with larger numbers of patients are required.

Increasing host cellular receptor-angiotensin-converting enzyme 2 expression by coronavirus may facilitate 2019-nCoV (or SARS-CoV-2) infection.

The ongoing outbreak of a new coronavirus (2019-nCoV, or severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) has caused an epidemic of the acute respiratory syndrome known as coronavirus disease (COVID-19) in humans. SARS-CoV-2 rapidly spread to multiple regions of China and multiple other countries, posing a serious threat to public health. The spike (S) proteins of SARS-CoV-1 and SARS-CoV-2 may use the same host cellular receptor, angiotensin-converting enzyme 2 (ACE2), for entering host cells. The affinity between ACE2 and the SARS-CoV-2 S protein is much higher than that of ACE2 binding to the SARS-CoV S protein, explaining why SARS-CoV-2 seems to be more readily transmitted from human to human. Here, we report that ACE2 can be significantly upregulated after infection of various viruses, including SARS-CoV-1 and SARS-CoV-2, or by the stimulation with inflammatory cytokines such as interferons. We propose that SARS-CoV-2 may positively induce its cellular entry receptor, ACE2, to accelerate its replication and spread; high inflammatory cytokine levels increase ACE2 expression and act as high-risk factors for developing COVID-19, and the infection of other viruses may increase the risk of SARS-CoV-2 infection. Therefore, drugs targeting ACE2 may be developed for the future emerging infectious diseases caused by this cluster of coronaviruses.

Long-term coexistence of SARS-CoV-2 with antibody response in COVID-19 patients.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causing coronavirus disease 2019 (COVID-19) has spread worldwide. Whether antibodies are important for the adaptive immune responses against SARS-CoV-2 infection needs to be determined. Here, 26 cases of COVID-19 in Jinan, China, were examined and shown to be mild or with common clinical symptoms, and no case of severe symptoms was found among these patients. Strikingly, a subset of these patients had SARS-CoV-2 and virus-specific IgG coexist for an unexpectedly long time, with two cases for up to 50 days. One COVID-19 patient who did not produce any SARS-CoV-2-bound IgG successfully cleared SARS-CoV-2 after 46 days of illness, revealing that without antibody-mediated adaptive immunity, innate immunity alone may still be powerful enough to eliminate SARS-CoV-2. This report may provide a basis for further analysis of both innate and adaptive immunity in SARS-CoV-2 clearance, especially in nonsevere cases.