COVID-19 Roundup: Masks, COVID-19 Severity, and Transmissibility

CDC Updates Mask Recommendations1

The Centers for Disease Control and Prevention (CDC) updated their mask guidelines to encourage more people to wear N95 or KN95 masks to help slow the spread of COVID-19. CDC officials say N95 or KN95 masks are better than cloth masks and procedure masks at filtering air.

Early in the pandemic, US health officials warned that N95 and KN95 masks should be reserved for health care providers because of a shortage of supplies. CDC officials are no longer concerned about a shortage of N95 masks. They also recommend everyone find a mask that fits well and can be worn consistently, citing any mask is better than no mask at all.

Predicting COVID-19 Severity2

Results of a recent study show that antibodies in blood after a recent COVID-19 diagnosis can predict the severity of the disease. Blood samples were collected from 178 adults who contracted COVID-19 and had mild symptoms. Eventually, 15 participants went to the emergency department with severe symptoms. The researchers identified an early biomarker for risk of progression to severe symptoms. In the study, antibodies from an mRNA vaccine, like Pfizer’s vaccine, are different than participants with COVID-19 who later developed severe symptoms. The goal is to eventually create a test, given soon after a COVID-19 diagnosis, to help clinicians determine which patients likely need the most attention.

Infectious After 5-Day Quarantine3

A recent study suggests that many people with COVID-19 may still be infectious after a 5-day quarantine. The researchers looked for genetic material that SARS-CoV-2 produces when it is transmissible. After 5 days, 30% of people may have been infectious, and after 10 days, 10% of people may have been infectious. Some people still had possibly infectious levels of the virus for up to 68 days, and according to the researchers, there was nothing that set these participants apart. Therefore, the researchers would not have been able to predict who would remain infectious.


—Jessica Bard



  1. Types of masks and respirators. Centers for Disease Control and Prevention. Updated January 14, 2022. Accessed January 21, 2022.
  2. Chakraborty S, Gonzalez JC, Sievers BL, et al.  Early non-neutralizing, afucosylated antibody responses are associated with COVID-19 severity. Sci Transl Med. Published online January 18, 2022. doi:10.1126/scitranslmed.abm7853
  3. Davies M, Bramwell LR, Jeffery N, et al. Persistence of clinically relevant levels of SARS-CoV2 envelope gene subgenomic RNAs in non-immunocompromised individuals. Int J Infect Dis. Published online December 7, 2021.