Today's world is becoming a big village in which people are increasingly mobile and goods and materials are transported further and faster. Globalisation has both advantages and disadvantages. Infectious and vector-borne diseases associated with water are moving from place to place in a shorter time, and pathogens and vectors can also travel around the globe.

पिछ्ला सुधार: बुधवार, 25 जून 2014, 12:08 अपराह्न