US drugmaker Johnson & Johnson has started the last phase trial of the single-dose corona vaccine. Most pharmaceutical companies are testing a two-dose corona vaccine. Johnson & Johnson plans to conduct a vaccine test on 60,000 volunteers. Apart from the US, these trials are taking place in South Africa, Argentina, Brazil, Chile, Colombia, Mexico and Peru. The company’s late-stage trial will be conducted in as many as 215 sites. ALSO READ | India's Covid-19 Tally Surges Past 56 Lakh-Mark With 83,000 New Cases; Recovery Rate Stands At 81.25%

How’s the J&J trial different from others?

Other vaccines being developed by Moderna Inc, Pfizer Inc and AstraZeneca require two shots separated by several weeks, which make them much more difficult to administer.

The company will test whether the single-dose vaccine is effective in preventing Covid-19. This will be bigger than all the tests conducted so far on any vaccine. Earlier, any vaccine was tested on 30 thousand people.

Scientist Dr. Paul Stoffel said, "Tests on 60,000 people will show the effect on different types of people. We are hoping that the results will be seen by the end of this year or early next year. In case of emergency, a single-dose vaccine can be very useful. We will later test the booster doses. The results of the first phase show that only a single dose is enough to save people for a long time. "

The company plans to manufacture as many as 1 billion doses in 2021, and more after that

ALSO READ | New Research Suggests Dengue Antibodies Might Provide Some Immunity Against Covid-19

A look at several trials for Corona vaccine

A number of other countries are in the final stages of trials, including a vaccine produced by Moderna Inc. and Pfizer Inc. in the United States. Expectations have been solidified that at least one safe vaccine will come out by or before the end of this year.

Dr. Francis Collins, director of the National Institutes of Health, said, "We want to do everything to get the vaccine without compromising safety and effectiveness. We won't do it. We want to have a vaccine that saves lives to go. "

The trial will be overseen by an independent Data and Safety Monitoring Board (DSMB) that will review vaccine safety and effectiveness.  All three vaccines being organized and supported by the federal government's Operation Warp Speed - J&J's, Moderna's and AstraZeneca's - share a common an independent DSMB. However, Pfizer is running its own trial and has a separate DSMB.