This document provides information on common communicable diseases in the Philippines, including their causes, modes of transmission, incubation periods, signs and symptoms, methods of diagnosis, and treatment options. It discusses eight diseases: leptospirosis, malaria, sexually transmitted infections, schistosomiasis, tuberculosis, filariasis, rabies, and leprosy. For each disease, it lists the infectious agent, how the disease spreads, typical time for symptoms to appear after exposure, common signs and symptoms, laboratory tests used for diagnosis, and recommended medical treatments.