Climate Change 
 

Seasonal variation in Norovirus infection is a recognized but a poorly understood phenomenon. It is likely to be based on biological, environmental and behavioural factors that regulate transmission, virulence and persistence of the virions in host populations. Climate change predictions show that there is likely to be an increase in more intense rainfall events especially during the winter months. An increase in rainfall has implications on the quality of the coastal waters as a result of increased nutrient run off from land and storm water overflows, leading to a reduction in water quality around shellfish areas.