Immersion deaths are the deaths that occur while person is in water. It can be due to various reason such as the bodies retrieved from water may have died due to some natural disease before falling into the water or already under the water.
Irrespective of natural disease or injury, some persons who die after falling into water do not drown. Increased catecholamine plasma levels was measured after exposure to cold water baths which may lead to cardiac arrhythmias and increase the risk of sudden death.
Other cause of death in water can be drowning in which respiratory impairment has experienced. Autopsy signs of drowning depends on the delay in recovering the body from the water. Histological and chemical changes in drowning are also observed for diagnosis.