The World Health Organization says more than 100 possible vaccines are being developed to protect against COVID-19. But only six possible vaccines are currently in Phase 3 trials. Each trial will last for several months and include up to 30,000 people. One vaccine candidate under Phase 3 trial is from Britain’s University of Oxford and drug maker AstraZeneca. Sarah Gilbert, a leading scientist in the study, told BBC Radio that it is possible the team will have a vaccine by the end of the year. Dr. Anthony Fauci is the top U.S. infectious diseases expert. He told Reuters recently that a trial by Moderna and the National Institutes of Health could produce results by November or December. Other efforts like the joint study from U.S.-based drug maker Pfizer and Germany’s BioNTech will come later. Some experts are not sure whether Phase 3 trials can be completed that soon. The trials must study possible side effects of the vaccines on different groups of people and they must include thousands of people.