Vaccine for COVID-19 is being developed at a rapid rate by many countries. When COVID-19 virus invades our bodies, they multiply. Our immune system is triggered to fight this invasion by producing a large number of white blood cells called Macrophages, B-lymphocytes and T-lymphocytes which destroy the virus. This “fight” causes the symptoms like fever, headache and others. When the symptoms become uncontrollable, the person is affected seriously and sometimes is fatal.
However, once the person recovers, the immune system of the person still has the memory of these cells. When the same virus attacks for a second time, the body responds immediately and gets rid of the virus.
Some vaccines are to be taken in one dose and some in two doses. For the two-dose vaccine immunity starts working after about 2 weeks of the first dose, but the immunity sets in only about two weeks after the 2nd dose. For the one-dose vaccine, the immunity sets in after about 2 weeks of the shot. This immunity may not last for a life-time, but scientists are working to develop a vaccine that lasts long enough to get out of the pandemic.
COVID-9 vaccines trigger immunity response in our bodies to the COVID-19 virus without the symptoms that cause the illness. The working of the vaccine depends on the type of vaccine manufactured. But all types of vaccines aim to help retain a memory of the fighter cells against the COVID-19 virus. Some vaccines may cause mild symptoms such as fever and fatigue, which are normal. Extreme illnesses in response to vaccines are very rare.
Types of COVID-19 vaccines :
The three types of COVID-19 vaccines are currently under development. Some are undergoing Phase 3 trials, that is, large-scale clinical trials.
COVID-19 vaccine side-effects:
Side-effects of COVID-19 vaccine are usually minimal and occur as the body reacts to the foreign material that the vaccine contains. People who have had allergic reactions to any ingredient of the vaccine must exercise caution in taking the vaccine. Reaction within 4 hours of the vaccination with hives, excessive swelling or wheezing is considered to be an allergic reaction.