Moderna, Pfizer, AstraZeneca, and Johnson & Johnson are leading candidates for the completion of a Covid-19 vaccine likely to be released in the coming months. These companies have published their vaccine trial protocols. Close inspection of the protocols raises surprising concerns. These trials seem designed to prove their vaccines work, even if the measured effects are minimal. Prevention of infection is not a criterion for success for any of these vaccines. In fact, their endpoints all require confirmed infections and all those they will include in the analysis for success, the only difference being the severity of symptoms between the vaccinated and unvaccinated. Measuring differences amongst only those infected by SARS-CoV-2 underscores the implicit conclusion that the vaccines are not expected to prevent infection, only modify symptoms of those infected. We all expect an effective vaccine to prevent serious illness if infected. Three of the vaccine protocols - Moderna, Pfizer, and AstraZeneca - do not require that their vaccine prevent serious disease only that they prevent moderate symptoms which may be as mild as cough, or headache. A vaccine must significantly or entirely reduce deaths from Covid-19. None list mortality as a critical endpoint.