The anecdote provided by Dr. Loge documents Jefferson's extraordinary concern for the scientific advances of his time and for public health. In contrast to the lack of interest shown by his predecessor, John Adams, Jefferson tried to diffuse smallpox vaccine to indigenous U.S. populations [1].

We do not question the historical importance of the event narrated by Dr. Loge, but as he himself recognizes, history is full of "ifs." If the circumstances of Lewis's expedition had been more favorable as far as the vaccine is concerned, the result would undoubtedly have been an important historical episode, comparable to Charles IV of Spain's Vaccine Expedition [2]. Unfortunately, this was not the case. We believe that the relationship among Lewis, the expedition to explore Louisiana, and the smallpox vaccine, although historically important, is merely an anecdote from the point of view of the fight against smallpox. Edward Jenner himself sent the Abenakis a book that explained the art of vaccination [3]. The first official action against smallpox occurred in 1832, when the U.S. Congress allocated $12 000 to ensure the vaccination of the Native Americans [3]. This occurred 2 years after President Andrew Jackson (who had smallpox at 14 years of age) initiated a massive resettlement of Indians from the east to the west of the country [3]. The effectiveness of these measures was dubious because from 1836 to 1840, a pandemic lead to the practical disappearance of the Omaha, Oto, Missouri, and Mandan tribes [3].

We do not agree with Dr. Zelicoff that the final part of our article on the history of smallpox, and not on the history of the smallpox virus, is incomplete. Our objective was to reveal the polemic generated by the possible destruction of the smallpox virus. We agree that enormous knowledge on the selective inhibition of primary immune system responses may emerge from the study of the smallpox virus. The final decision should be based on consensus of the scientific community, which should first and foremost remember that never again should a human being die of smallpox. The opinion of those like Dr. Zelicoff) who think that the benefits of conservation of the virus are greater than those of its destruction should be considered, but so should the opinion of those who believe that maintaining the smallpox virus, even with the greatest security measures possible, involves a potential threat [4, 5] that a species as unpredictable as the human race should not have within its grasp.