No, they are not. They are likely to be much more dangerous for those groups, but the flu or pneumonia can kill anyone. Some strains of the flu are believed to

No, they are not. They are likely to be much more dangerous for those groups, but the flu or pneumonia can kill anyone. Some strains of the flu are believed to be more deadly to the "strong" patients, due to a phenomena known as "cytokine storm" - where the strong immune system response directly contributes to death.