First, we have to know what a vaccine is. A vaccine is a part of the virus that helps your body fight the real virus by letting your antibodies explore the virus part, then defeat it. In the Covid-19 virus, the spiked glycoprotein or a part of RNA(genetic code as shown in the picture below), is used in making the vaccine.
The first vaccine was developed for smallpox in 1796. Smallpox was very deadly, and in those times, they tried everything. Microscopes couldn’t see that germs were causing this illness, but they did find something strange: People who were around cows wouldn’t get smallpox. Instead, they would get something called cowpox. Cowpox acted like a vaccine but was less dangerous than smallpox. Sure it caused fever, but mild fever. It also caused aching, but only in the hands. Scientists decided to try to give people who weren’t sick cowpox. And guess what? It worked! This is how the first vaccine was made.
In recent times with the COVID pandemic. The vaccines were developed to fight COVID.
The three Covid vaccines in America are Pfizer, Moderna, and Johnson and Johnson (J&J). While Pfizer and Moderna need two doses, Johnson and Johnson’s vaccine only needs only one.
The main problem with the Covid-19 vaccine has to do with transportation: it has to be kept below freezing. The Pfizer Vaccine has to stay between -112ºF to 76ºF, while Moderna has to stay at around -4°F. However, the J & J vaccine only has to stay refrigerated at about 35.6 to 46.4 degrees Fahrenheit.
The vaccine is not 100% effective, the effectiveness of the vaccine ranging between 70 to 95%, so you still have to mask and follow social distancing and mistrust in people to vaccinate are other challenges.