A multidisciplinary team of researchers associated with Boston Medical Center and Boston University conducted a systematic review on 74 studies regarding COVID-19 guidelines in new mothers. Findings suggest that vertical transmission of COVID-19 via breastfeeding is highly unlikely, however mask usage, hand hygiene, breast cleaning, and pump cleaning were suggested (Table 1). Some studies recommended separation of the mother and newborn immediately after birth, while some state the benefits of skin-to-skin contact and breastfeeding outweighed the risks of COVID transmission (Table 2). Overall, the authors suggest decision making to be shared between the parents and provider to ensure safe practices.

A study conducted by researchers affiliated with BioNTech conducted an extended analysis of the immunogenicity of the BNT152b2 vaccine, a lipid nanoparticle (LNP) formulated nucleoside-modified mRNA encoding SARS-CoV-2 given in priming doses of 1, 10, 20, or 30 ug on Day 1 followed by a booster dose on Day 22. They found that the vaccine led to 3.3 fold increased neutralizing antibody titers compared to unvaccinated individuals who had recovered from COVID-19 infection. Additionally, the BNT152b2 vaccination effectively neutralized 22 pseudo-typed viruses with S-mutations of the prevalent circulating SARS-CoV-2 variants. These findings indicate broad BNT162b2-elicited immune recognition and response with SARS-CoV-2-specific neutralizing antibodies and poly-specific CD4 and CD8 T-cell responses including against the B.1.1.7, P.1, and B.1.351 variant lineages at tolerable doses.

A research team from Cincinnati Children's Hospital (OH), Kaiser Permanente Vaccine Study Center (CA), and the California Research Foundation, San Diego (CA) funded by BioNTech and Pfizer used a multinational, placebo-controlled, observer-blinded trial of 30 μg of BNT162b2 delivered in two doses to determine immunogenicity in 12-to-15-year-old participants. 1131 received BNT162b2, and 1129 received placebo; there were no vaccine-related serious adverse events and few overall severe adverse events. Noninferiority of the immune response to BNT162b2 in 12-to-15-year-old participants as compared with that in 16-to-25-year-old participants was determined by measuring neutralizing titers after dose 2. The observed vaccine efficacy was 100% (95% CI, 75.3 to 100) and no COVID-19 cases with an onset of 7 or more days after dose 2 were noted among BNT162b2 recipients (who did not have previous infection), while 16 cases occurred in placebo recipients. Overall, BNT162b2 vaccine in 12-to-15-year-olds produced a greater immune response than in young adults and was shown to be both safe and highly effective.

Researchers at the Health Information and Quality Authority in Ireland. performed a systematic review of of 11 cohort studies including 615,777 patients who recovered from COVID-19 to quantify risk of reinfection with SARS-Cov-2. The median follow-up was 131 days (4.4 months; range of medians: 54–210 days) and with a maximum follow-up of 10 months. They found reinfection rates to be between 0-1% (median PCR-confirmed reinfection rate: 0.27%) with no studies reporting an increase risk of infection with increasing time since recovery.

In an editorial, cardiology specialists associated with Tufts Medical Center discuss their recommendations for athletes returning to play after recovering from COVID-19. Before returning to play, the most practical approach of cardiac screening should include basic COVID-19 symptoms in addition to ECG, echocardiography, and troponin levels. Checking for abnormalities in CMR imaging due to myocarditis may be beneficial because of absence of myocarditis symptoms in some athletes, however the significance is unknown and access to CMR is limited. Overall, these screening recommendations can detect many cases of cardiac involvement post-COVID-19 prior to returning to sports.