Page 43 3) Epidemiological Surveillance Various studies and surveys are used to provide detailed information on the pandemic. Apart from routine epidemiological surveillance, sentinel surveillance is another principal source of information. Sentinel surveillance targets pregnant women. 4) Research Research focuses on: - Viral forms; Immunization; Treatment in collaboration with practitioners of traditional medicine. Furthermore, the Chantal Biya International Research Centre, led by the eminent professors Luc Montagnier and Gallo, who together discovered the Aids virus, is conducting research into vaccines. The increasing exposure of certain socio-professional groups to the disease has led to the identification of five groups in Cameroon whose behaviour puts them at risk:      Prostitutes; The military, police and related personnel; Truck drivers; Prisoners; Young people including girls, who have a higher HIV prevalence rate. 5) Sexually Transmitted Disease (STD) Control The main components of STD control are:    Attendance at a health facility as soon as the first symptoms appear in order to avoid self-medication; Use of algorithms to enable medical personnel treat STDs easily and efficiently; The use of IEC to promote sexually responsible behaviour.