| Date | 1803 |
| Author | Anon. |
| Contribution | Doctors from Spain reached Mexico to teach vaccination |
| Reference | McNeill |
| Notes | McNeill, p. 251. Another example of the successful exploitation of the immune response to germs, without knowledge of germs. |
| Category | Immunology |
| Pathogen Class | General |
Copyright © 2007- William C. Campbell. All rights reserved.