Recommendations for control and prevention of infections for pediatric orthopedics during the epidemic period of COVID-19

The outbreak of Coronavirus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged and spread rapidly throughout the world. As of February 29, 2020, 79 389 cases of COVID-19 have been reported, and the outbreak is linked to 2838 deaths. The population is generally susceptible to the disease, and differences in incubation periods after infection exist among individuals. These two aspects of COVID-19 pose significant challenges to pediatric orthopedic diagnosis and treatment. As a dedicated center for managing pediatric cases of SARS-CoV-2 in Shanghai, our hospital has mobilized all branches and departments to undertake joint actions for scientific prevention and control, precise countermeasure and comprehensive anti-epidemic efforts. Combined with our experience, we have consulted the relevant national regulations and the latest research advances and have formulated the prevention and control measures of SARS-CoV-2 infection, including outpatient, emergency, inpatient and surgical cares, for clinical practices of pediatric orthopedics according to the physicochemical properties of SARS-CoV-2. It may serve as practical references and recommendations for managing SARS-CoV-2 infection in other pediatric specialties and in other hospitals.

MCMV based vaccine vectors expressing full-length viral proteins provide long-term humoral immune protection upon a single-shot vaccination (preprint)

Global pandemics by influenza or coronaviruses cause severe disruptions to the public health and lead to severe morbidity and mortality. Vaccines against these pathogens remain a medical need. CMV (cytomegalovirus) is a β-herpesvirus that induces uniquely robust immune responses, where outstandingly large populations of antigen-specific CD8+ T cells are maintained for a lifetime. Hence, CMV has been proposed and investigated as a novel vaccine vector expressing antigenic peptides or proteins to elicit protective cellular immune responses against numerous pathogens. We generated two recombinant murine CMV (MCMV) vaccine vectors expressing the hemagglutinin (HA) of influenza A virus (MCMVHA) or the spike protein of the severe acute respiratory syndrome coronavirus 2 (MCMVS). A single shot of MCMVs expressing either viral protein induced potent neutralizing antibody responses, which strengthened over time. Importantly, MCMVHA vaccinated mice were protected from illness following challenge with the influenza virus, and we excluded that this protection was due to effects of memory T cells. Conclusively, we show here that MCMV vectors do not only induce long-term cellular immunity, but also humoral responses that provide long-term immune protection against clinically relevant respiratory pathogens.