New York: American pharmaceutical company Pfizer and German company BioNtech have announced a medical trial of an improved version of their Covid 19 vaccine.

According to the details, Pfizer and Bio-Tech say that they are further improving their vaccine for coronavirus, and in this regard, it will be medically tested.

The companies said in a joint statement on Thursday that the goal of improving the vaccine was to prevent serious infections in the delta variant of the coronavirus, and that a medical trial of the improved vaccine was expected in August.

The two companies have also released the results of their clinical trials on the efficacy of the third vaccine of the current vaccine of Covid 19, saying that six months after the second vaccine, the third vaccine was discovered in South Africa. Increased resistance 5 to 10 times.

He said the data also indicated that six months after the second vaccine of the current vaccine, the vaccine's ability to protect against the coronavirus may be weakened.

The companies argue that a third vaccine may be needed to maintain the highest level of immunity over a period of 6 months to a year after the completion of the two-vaccination process.

However, the CDC says that as soon as the scientific evidence suggests that the immune system needs to be strengthened, there will be no delay in getting a third vaccine, given the number of Americans who have had both. They do not currently need a third immunization boost.