When 2020 was just beginning, the existence of companies like BioNTech or Moderna was unknown to most mortals. Also unknown then was the importance that pharmaceutical giants like Pfizer, Johnson & Johnson or AstraZeneca would gain in our daily lives in the fight against the pandemic that was officially declared on March 11, 2020.

Two doses of the Pfizer vaccine is not enough to be immunised for life against covid-19. Uğur Şahin, co-founder of the German laboratory BioNTech, which developed this vaccine, confirmed on Wednesday that, after nine months to a year after the second injection, it will be necessary to receive a third one so that the level of protection offered by the vaccine does not drop more than necessary. And, from then on, the operation will have to be repeated every twelve to eighteen months.