query: When was the flu vaccine introduced?
passage: Influenza vaccine
Vaccination against influenza began in the 1930s with large scale availability in the United States beginning in 1945.[12][13] It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system.[14] The wholesale price in the developing world is about $5.25 USD per dose as of 2014.[15] In the United States, it costs less than $25 USD as of 2015.[16]
passage: Anthrax vaccine adsorbed
The vaccine efficacy of AVA in humans was initially established by Philip S. Brachman of the U.S. Public Health Service (PHS) in a controlled study undertaken between 1954 and 1959. The study field sites were four wool-sorting mills in the northeastern United States where employees were sometimes exposed to anthrax spores in the course of their work. Over the five years, 379 vaccinees were compared against 414 unvaccinated control subjects. There were 23 cases among controls (5 of them inhalation anthrax) compared with 3 cases among vaccinated (0 inhalation cases). The vaccine was judged to have a 92.5% vaccine efficacy against all types of anthrax experienced. Subsequently, there were no controlled clinical trials in humans of the efficacy of AVA due to the rarity of the condition (especially in the inhalational form) in humans and the ethical inadmissibility of conducting dangerous challenge studies in human subjects. Supportive animal challenge studies were done, however, showing that unvaccinated animals uniformly die whereas vaccinated animals are protected. About 95% of rhesus monkeys (62 of 65) survived challenge, as did 97% of rabbits (114 of 117). Guinea pigs (which are a poorer model for human anthrax than are monkeys or rabbits) showed a 22% protection (19 of 88).