The vaccine is made by the Serum Institute of India using five strains of the virus collected exclusively in Sub-Saharan Africa. It has a special characteristic: it is heat-resistant (thermostable at 37°C for between six months and a year). Unlike the majority of vaccines, which must be kept in refrigerators at between 2°C and 8°C, this new vaccine can be kept at room temperature and can tolerate temperatures up to 37°C (for between six months and one year) without losing its properties. At the Epicentre office in Maradi, the vaccines are stored in the pharmacy before being sent out to the health centres where the study is taking place.