Further reading/resources: 

• Evaluating SARS-CoV-2 Vaccines After Emergency Use Authorization or Licensing of Initial Candidate Vaccines (JAMA Network)
• SARS-CoV-2 Vaccines: Much Accomplished, Much to Learn (American College of Cardiology)
• Handicapping the COVID Vaccine Horse Race (Medscape)
• New COVID-19 vaccine trials starting in children (MSN)
• Pfizer says its Covid vaccine trial for kids ages 12 to 15 is fully enrolled (CNBC)
• South Africa Halts AstraZeneca Vaccine Rollout Over Effectiveness Doubts With New Variant (Slate)