Louis Pasteur's Revolutionary Vaccines

Louis Pasteur was born in Dole, France in 1822. He grew up in the nearby town of Arbois, where a rabid wolf terrorized the village and caused many people's deaths. This incident is believed to have had some influence on Pasteur's studies. Pasteur's personal life was full of tragedy and sickness. These occurrences may have pushed him to try to spare others the pain and heartbreak of losing their loved ones. Before Pasteur's vaccine, rabies was a deadly disease, being bitten by a rabid animal and a painful, certain death for the victim. Pasteur's vaccine reformed this common belief. This vaccine was first used on a nine-year-old boy named Joseph Meester. After being bitten, the child had gone to his doctor to have the wounds treated with the only known possible cure at the time. This was to have the wounds cauterized, or burned away, with carbolic acid. Prior to this incidence, Pasteur had been researching rabies over the past five years. At the time Joseph's father came to Pasteur for help, Pasteur believed that he had created a vaccine that, after a few injections, would cause a person to become immune to the rabies disease. However, Pasteur didn't believe that the vaccine was ready to be used on a human because the only promising results had been in rabbits and dogs in the past. Also, there was no way to be sure if Joseph was actually infected with rabies until he started exhibiting symptoms. But if they waited for Joseph to actually exhibit symptoms, they risked the possibility that the vaccine may not have enough time to work properly. Pasteur knew this from experience. The vaccine had only been used on a human with rabies once before. However, because the little girl was already exhibiting symptoms of the disease, she later died of the virus. If the vaccine didn't work, or was fatal to Joseph, Pasteur's career would have ended in disgrace, and he may have even been charged with boy's murder. Worse yet, other researchers may have been too afraid of criminal charges to continue their work on other life-saving vaccines. Pasteur was not a medical doctor, so he consulted two doctors that he trusted for their medical opinions on the matter. They both agreed that Pasteur should try the vaccine immediately. The injections of the vaccine began that night, and lasted 10 days. On July 16th, Pasteur looked on as his medical assistant, Dr. Grantcher, injected Joseph with what would normally have been a fatal dose of the rabies virus. Pasteur watched Joseph closely, and waited in agonizing suspense. Miraculously, Joseph still showed no signs of the rabies disease, even 25 days after his first injection of the vaccine. Pasteur gave Joseph one of the rabbits from the lab to keep as a pet, and said goodbye to him. Not much was recorded about what happened to Joseph Meester after that, but it is known that he lived to be about 64 years old. The second revolutionary vaccine that Louis Pasteur created was for the anthrax virus. Anthrax was considered to be a big economic problem to farmers at this time. It killed off hundreds of their livestock, which was costing the farmers thousands of dollars every year, and putting them into debt. The Minister of Agriculture was concerned, so in 1877, he called upon Louis Pasteur to study the disease. In the mid-1800s, many people thought the cause of anthrax included evil spirits, witches, and toxic herbs. Previous scientists who had researched the anthrax disease had gotten conflicting results. These contradictory findings intrigued Pasteur, and he was eager to start his research. Pasteur placed one drop of a sheep's blood that had been afflicted with anthrax into a 50 milliliter sterile culture, grew the bacterium, and repeated the process 100 times. This diluted the culture so much that not even one molecule of the original culture should have remained. However, the 100th culture was just as active as the first in producing anthrax. These findings firmly established the germ theory of disease. But this discovery didn't provide a cure for the anthrax virus. Ironically, Pasteur's studies on chicken cholera led to the creation of a vaccine for anthrax. During the summer heat, Pasteur had left some of the cholera cultures used for infection on the shelves in his Arbois laboratory while he went to Paris. When he returned and tried to use the cultures, he discovered that they no longer infected the chickens. Pasteur and his collaborators made fresh cholera cultures and tested them on both the chickens previously injected with the non-infectious cholera cultures and those who hadn't been. The results were shocking. All chickens previously inoculated with the heated cholera cultures lived, while all others died. Pasteur soon realized that he was repeating Jenner's studies from 80 years earlier. Jenner discovered that he could immunize humans to smallpox by injecting them with a small amount of a heat-killed cowpox virus. Pasteur concluded that when heated to certain temperatures, the cholera virus would be attenuated, or rendered unable to infect a person. Pasteur then wondered, if attenuating the cholera virus could provide a vaccine, why wouldn't the anthrax virus behave in the same way? And so began the creation of the vaccine. Pasteur and his team worked to attenuate the virus and create enough of it for a small trial on 14 sheep in the laboratory. The farming community was overjoyed with the news that the trial had been successful. The news spread fast, and Pasteur was soon issued a challenge from a well-known veterinarian to test the vaccine in a larger trial in Milan, France. Pasteur was told that for his vaccine to be deemed successful, all unvaccinated sheep must die, and all vaccinated sheep must live. Again, Pasteur's career hung on the outcomes of a vaccines trial. Pasteur accepted the challenge by saying, With many spectators watching, the trial began. Many people wanted to know if the vaccine would live up to Pasteur's claims. Even Pasteur was privately concerned that he had been foolish to accept the challenge so quickly. However, two days after the final dose of the anthrax virus, all vaccinated sheep were alive and all unvaccinated sheep were dead. The news of these miraculous results, and with it, Pasteur's fame, soon spread through Europe. Within 10 years, over 3.5 million sheep and half a million cattle had been vaccinated with Pasteur's vaccine. Anthrax vaccine is still used today in livestock and is also used for soldiers in the military who may come into contact with the anthrax virus. Pasteur's revolutionary vaccines went on to help both victims of rabid animal bites and the French economy. His rabies vaccine reformed the way bite wounds were treated and greatly reduced their mortality rates. His anthrax vaccine saved the French economy at least 7 million francs, which is about 1.5 million US dollars. This was estimated to have been enough to cover France's monetary cost for the Franco-Prussian War. Pasteur will always be remembered for his revolutionary work and his perseverance in pursuing it.