Mild Breakthrough Infection in a Healthcare Professional Working in the Isolation Area of a Hospital Designated for Treating COVID-19 Patients - Shaanxi Province, China, March, 2021.

WHAT IS ALREADY KNOWN ABOUT THIS TOPIC?: Healthcare workers are at high risk of acquiring COVID-19 from occupational exposure to COVID-19 virus during their daily medical service work. Excellent infection prevention and control measures and adequate personal protective equipment (PPE) are essential to reduce the risk of hospital-acquired COVID-19. WHAT IS ADDED BY THIS REPORT?: On March 17, 2021, a female healthcare professional who already received both doses of the COVID-19 vaccination and was working in the isolation area of a designated COVID-19 hospital was diagnosed with COVID-19 in Xi'an city. Her exposure likely occurred five days before illness onset when she obtained nasopharyngeal and oropharyngeal swabs from the two imported cases that were identified as belonging to the B.1.1.7 lineage, the variant first detected in the United Kingdom. WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICES?: Since the healthcare worker had been fully vaccinated and had mild symptomatology, it is considered a mild breakthrough infection. All vaccines are associated with breakthrough infections. In addition to rigorous adherence to infection prevention and control measures, use of adequate PPE, and using good clinical practices, the potential role of chronic upper respiratory infection in acquiring COVID-19 during medical procedures deserves further consideration.

DCs-based therapies: potential strategies in severe SARS-CoV-2 infection.

Pneumonia caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is spreading globally. There have been strenuous efforts to reveal the mechanisms that the host defends itself against invasion by this virus. The immune system could play a crucial role in virus infection. Dendritic cell as sentinel of the immune system plays an irreplaceable role. Dendritic cells-based therapeutic approach may be a potential strategy for SARS-CoV-2 infection. In this review, the characteristics of coronavirus are described briefly. We focus on the essential functions of dendritic cell in severe SARS-CoV-2 infection. Basis of treatment based dendritic cells to combat coronavirus infections is summarized. Finally, we propose that the combination of DCs based vaccine and other therapy is worth further study.

Influence of Different Inactivation Methods on Severe Acute Respiratory Syndrome Coronavirus 2 RNA Copy Number.

The outbreak of coronavirus disease 2019 (COVID-19) has spread across the world and was characterized as a pandemic. To protect medical laboratory personnel from infection, most laboratories inactivate the virus causing COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in clinical samples before testing. However, the effect of inactivation on the detection results remains unknown. Here, we used a digital PCR assay to determine the absolute SARS-CoV-2 RNA copy number in 63 nasopharyngeal swab samples and assess the effect of inactivation methods on viral RNA copy number. Viral inactivation was performed by three different methods: (i) incubation with the TRIzol LS reagent for 10 min at room temperature, (ii) heating in a water bath at 56°C for 30 min, and (iii) high-temperature treatment, including autoclaving at 121°C for 20 min, boiling at 100°C for 20 min, and heating at 80°C for 20 min. Compared to the amount of RNA in the original sample, TRIzol treatment destroyed 47.54% of the nucleocapsid protein (N) gene and 39.85% of open reading frame (ORF) 1ab. For samples treated at 56°C for 30 min, the copy number of the N gene and ORF 1ab was reduced by 48.55% and 56.40%, respectively. The viral RNA copy number dropped by 50 to 66% after heating at 80°C for 20 min. Nearly no viral RNA was detected after autoclaving at 121°C or boiling at 100°C for 20 min. These results indicate that inactivation reduced the quantity of detectable viral RNA and may cause false-negative results, especially in weakly positive cases. Thus, use of the TRIzol reagent rather than heat inactivation is recommended for sample inactivation, as the TRIzol reagent had the least effect on the RNA copy number among the tested methods.