· Children may also experience long-term effects of COVID-19 infections.A letter to the editor conducted by researchers affiliated with the Department of Pediatrics at La Paz University Hospital in Madrid, Spain outlines their telephone consults performed from March to June 2020 for follow-up of children with COVID-19 infection, 8 of whom had long duration symptoms including low-grade fever, intense asthenia, and severe headache, requiring multiple ED visits but no hospital admission. Confirmation of SARS-CoV-2 infection was only confirmed in 2 out of 8 patients, however, delays in RT-PCR tests and shortages could cause under-diagnosis of COVID-19 and the stressful nature of the COVID-19 pandemic could also exacerbate these clinical symptoms. Though there is not a plethora of evidence, there is growing data suggesting the susceptibility of children to the long-term effects of COVID-19 infection.
Transmission & Prevention
· COVID vaccines help reduce infections in vaccinated individuals at University of Texas Southwestern Medical Center. A chief quality officer from the University of Texas Southwestern Medical Center (UTSW) reports findings in the first month of their COVID-19 vaccination program (December 15, 2020 to January 28, 2021) in which 59% of 23,234 eligible employees received at least 1 dose of either Pfizer or Moderna mRNA vaccines. They found most new infections (234 of 8969) occurred in non-vaccinated employees, with few (4 of 8121) in the fully vaccinated population (p<0.01). Authors suggest that mRNA vaccinations tremendously impact the rate of new SARS-CoV-2 infections and emphasize the importance of addressing vaccine hesitancy.
· The Oxford-AstraZeneca COVID vaccine requires lower cost of manufacturing and storage but has potential links with rare adverse effects that required further investigation. A team of journalists writing for Nature in March 2021 review updated data regarding the Oxford-AstraZeneca vaccine. Manufacturers reported overall efficacy of 76% with similar efficacy against variants and lower cost of manufacturing and storage compared to other vaccines. However, due to potential links between the vaccine and rare clotting conditions the authors suggest that more data analysis will be required before the vaccine is approved for use in the United States.
· COVID vaccines are effective at preventing COVID-19 infections. Researchers associated with UCLA and UCSD studied the incidence of COVID-19 in 36,659 vaccinated healthcare workers and found that 379 workers tested positive for SARS-CoV-2 through repeated nasal PCR testing, 71% of whom tested positive within 2 weeks after receiving the first dose. 37 workers tested positive after receiving the second dose, 22 of whom tested positive within the first week. Overall, the absolute risk of testing positive for SARS-CoV-2 after vaccination was 1.19% at UCSD and 0.97% at UCLA health systems, indicating that both doses or even one dose of the COVID-19 vaccine is indeed effective at preventing SARS-CoV-2 infection.
· Patients with past SARS-CoV-2 infection have higher levels of antibodies after vaccination. An immunology research team from Children's Mercy Kansas City used a multiplex bead-binding assay to assess antibody levels at baseline and 3 weeks after the first dose of the BNT162b2 (Pfizer) SARS-CoV-2 mRNA vaccine in 36 health care workers with laboratory-confirmed SARS-CoV-2 infection 30 to 60 days before they received the vaccine and 152 health care workers without past SARS-CoV-2 infection. After the first vaccine dose, they found that patients with past SARS-CoV-2 infection or seropositive status had higher levels of antibody to SARS-CoV-2 antigens as well as higher levels of neutralizing antibodies. Authors suggest further investigation into the duration of antibody responses and protective immunity measures is needed in order to confidently recommend an effective immunization program.
· Solid-organ transplant patients may have a reduced immune response to SARS-CoV-2 antigens. A serological study conducted by researchers affiliated with multiple medical institutions in Spain and France analyzed 44 patients who were hospitalized with moderate/severe COVID-19 disease (28 solid-organ transplant (SOT) recipients and 16 immunocompetent (IC) patients), and found that SOT patients had lower IgG seroconversion rates (77% vs. 100%, p=0.044) and decreased reactive cytokine-producing T-cell frequencies to 4 main immunogenic SARS-CoV-2 antigens, indicating that SOT patients were delayed in achieving a strong immune response compared to immunocompetent patients. Worsening clinical outcomes were associated with a lesser SARS-CoV-2 reactive IL-2 producing T-cell response. Despite an initial delay in response, the serological and functional T-cell immune response were observed to be comparable to immunocompetent patients following COVID-19 infection, confirming the need for active immunization especially in SOT patients.