anticipated or accompanied by silicosis and anchylostomiasis (caused by a small intestinal worm that creates a state of anemia propitious to tuberculosis). After finding a better solution to anchylostomiasis, he focused on creating a vaccine using the bacillus responsible for bovine tuberculosis, very similar to the human one, as it caused almost the same symptoms. Having observed that most actinomycetales are saprophytes, that are able to survive outside of living organisms, with the help of a veterinarian, Camille Guerin, he attempted to create an environment for the bacillus that, in time, altered its features by eliminating the virulence and leaving only the antigenic power. The environment deemed appropriate for the denaturation of the Mycobacterium bovis was a compost of potatoes cooked in the bile of an ox treated with glycerine, and Calmette re-inseminated it every three weeks for thirteen years while checking for an enfeeblement of the pathogenic power of the bacillus. Having finally lost completely its virulence, the bovine tuberculosis germ grown with their method was the principal prophylactic weapon against human tuberculosis, and it helped to reduce considerably the frequency of this disease. While experimenting on chimpanzees in Kindia, Calmette also discovered that it can notably weaken some leprosy manifestationsits bacillus presents some similarities with Koch's. Calmette's work in Saigon In Saigon Albert Calmette also created the first overseas branch of the institute, where he produced an amount of smallpox and rabies vaccines sufficient to satisfy the needs of the population and started a study on venomous snakes, particularly cobras. During these studies, Calmette discovered that the power of the venom, as well as that of tetanus, could be countered by the use of alkaline hypochlorites, and was able therefore to create a serum, effective if injected right after the cobra's bite. Back in France, he acquired enough snakes to continue his work and create a serum for the local population. Nicolle's work on epidemic typhus The scientist and writer Charles Nicolle while in Tunis studied how epidemic typhus – known for the red spots it left on sick people that disappeared before their death – was transmitted. His insight into the mode of transmission occurred while he was visiting the hospital: patients were washed and given clean clothes on admission, and no new cases occurred within the hospital. This made him realise that the vector of the disease were lice that were discarded with the patient's own