Thread by @DearPandemic

1/ Is there any research/guidance regarding the #vaccines for those of us who already had it?

A: Those who have had #COVID19 are recommended to receive the vaccine.

2/ Data from the #Pfizer & #Moderna vaccine trials demonstrated safety in participants that have had #Covid_19 previously. Scientists are hopeful that the vaccine will offer a higher level of protection than immunity to natural infection.

3/ Although the Pfizer & Moderna #vaccine excluded participants with a known history of #COVID19, a number of participants on both trials were found to have baseline antibodies against SARS-CoV2- indicating a prior infection.

4/ There were 1125 participants in the Pfizer trial & 675 participants in the Moderna trial with baseline antibodies. There were no safety signals from having a prior SARS-CoV2 infection. Moderna’s trial noted that people with prior #Covid infection had decreased adverse events.

5/ One of the reasons why the vaccine is recommended is because immunity to natural SARS-CoV2 infection is variable. #Antibodies after COVID19 infection can vary 200 fold! Some people may have no circulating antibodies & very little immunity, while others can have high levels.

6/ Even if someone has circulating antibodies, they may not have antibodies that are neutralizing- which stop the virus from entering the cells in our body. Immunity may only last several months & it is possible to be re-infected.

7/ The ACIP recommendation is for people that have a history of previous Covid infection to be vaccinated. Because there may be some immunity to SARS-CoV2 for 3 months post-infection, people may decide to delay vaccination until 3 months post-infection if they want.

8/ Testing for antibodies is not recommended for vaccine-decision making.

And if someone has a current SARS-CoV2 infection they should wait until recovered to receive a vaccination.

9/ On a personal note, this NG is grateful that her medical provider spouse is receiving the #vaccine although he has a history of viral infection. It will protect him & hopefully serve as another line of defense to prevent the virus from traveling home.