Just was realizing that Sayid never was inoculated like the rest of the group. DI gave a vaccine to recruits coming to the island. Desmond took it as well when Kelvin made him at the Swan. Aaron was inoculated in utero and also after his birth by Claire, but there is a question whether Claire herself was inoculated. The rest got shots when the came to the DI camp in 1977. I know that the whole story Kelvin gave Desmond about wearing a hazmat suit was made up to keep him at the hatch, but the shots were apparently considered necessary by Dharma. For what? Is this significant, especially since Sayid and maybe Claire are the only ones not inoculated and they are now infected?