The recommended schedule is two doses Pfizer-BioNTech’s, Moderna’s, AstraZeneca, Sinopharm and Sinovac COVID-19 vaccines; while one dose only is required for Janssen (Johnson & Johnson) vaccine. It is expected to take 7-14 days after the complete schedule to achieve optimal protection against COVID-19.
How long this protection will last is not yet known. However, it is estimated to be at least 8 months and probably around a year which is at least as long as the protection provided by having had the disease, but with the enormous advantage of not suffering the consequences of it thanks to vaccination. Also, it is expected that the immunity generated by the vaccine is higher than by the disease since the immune response to the vaccine is a more selective and powerful stimulation than the response with natural infection.
Vaccinated volunteers will be monitored in clinical trials during a period of 2 years so that we can collect the necessary information to answer these questions confidently on the characteristics of this protection.
- may require two doses for optimal protection
- are not immediately effective
- generate immunity of uncertain duration
- pose much less risk than natural infection.