"The Congregation for the Doctrine of the Faith has judged that ‘when ethically irreproachable Covid-19 vaccines are not available ... it is morally acceptable to receive Covid-19 vaccines that have used cell lines from aborted fetuses in their research and production process.’ However, if one can choose among equally safe and effective COVID-19 vaccines, the vaccine with the least connection to abortion-derived cell lines should be chosen. Therefore, if one has the ability to choose a vaccine, Pfizer or Moderna’s vaccines should be chosen over Johnson & Johnson’s."