The scientific gender hopes the injection strategy Combining many types of Vaccine Covid-19 will help solve logistics issues, even create better immunity.

Around the world, different pharmaceutical companies have developed the Covid-19 vaccine in unlike different ways.

Most countries in the world use a vaccine for each person injecting, but this is gradually changing, when some experts believe that the conversion to other vaccines in second injections can be enhanced

German Prime Minister Angela Merkel on June 22 was vaccinated by American Pharmaceutical company Moderna, two months after her first injection with Astrazeneca's vaccine, when some studies showed that the combination of two vaccines would be more effective.

A British small study on the combination of vaccines shows those who are injected by Pfizer after Astrazeneca nose, or vice versa, are more likely to develop symptoms after light or average vaccination than when injected with two doses of the same type

According to scientists, there are a number of bases to argue that two different Covid-19 vaccines help activate a strong and long-term immune response than injecting both doses from a company.

Each vaccine manufacturing company uses different NCOV protein fragments in their recipe.

Different vaccine development technologies are also thought to activate the unique capabilities of the immune system, because the protein proteins are not the same they use.

Vaccine Pfizer and Moderna contain a mRNA section, act as genetic materials to direct the production of protein protein ncov in the body.

Medical staff prepared a Dose of Astrazeneca's Covid-19 vaccine in Sidcup, southeast London, England, on January 7.

Some other Covid-19 vaccines rely on vector viruses.

In addition to Johnson & Johnson and Astrazeneca, Vaccine Sputnik V of Russia and Cansino of China also use vector virus technology.

Therefore, experts hope to combine different vaccines, such as using a mRNA-based vaccine, or type that includes another virus vector as a second dose, which can help reduce that risk.

Many studies in the world are underway, for both animals and people, to investigate safety levels, immune response types are created and the time of immunity when a person injecting two

The result of a test in Spain was conducted by the Carlos III Health Institute in Madrid with 663 participants, proving that the injecting of Astrazeneca and Pfizer had activated a strong immune response.

According to the test results announced on May 18, two-thirds of the test group was injected with the second dose with a Pfizer vaccine at least 8 weeks after the first dose in the Astrazeneca vaccine produced antibodies much higher than

Meanwhile, the control group with one-third of the participants did not inject the second dose and there was no change in the level of antibody.

Preliminary results from a German study also showed that the first Astrazeneca vaccine was injected, then the second dose of Pfizer helps to create more antibodies, providing better protection against worrying virus strains

Researchers at the UK Oxford University are also testing the safety and effectiveness of combining Astrazeneca and Pfizer vaccines.

The final result of the study, including the level of effectiveness of this way, is expected to be announced in June. A extended study is testing in combination of vaccines from Monderna and Novavax US pharmaceutical companies.

Concerns about new NCOV strains, capable of spreading stronger, are said to be one of the reasons to promote the combination of vaccination strategies.

Currently, the American Disease Control and Prevention Center only allows injecting the vaccination of Pfizer and Moderna in exceptions, such as limited vaccine sources or people who do not know their first nose

The Canadian Community Health Agency has recently agreed to combine different Covid-19 vaccines, if the supply problem makes people unable to inject the second dose of the same type as the first dose.

In addition to helping immunization regimen become more flexible, the most obvious benefit of the Vaccine combination strategy is to help solve logistics issues, in the context of many parts of the world deploying slow or missing vaccinations

The researchers hoped that the combination of many Vaccine Covid-19 would overcome this situation.