Disease and Environmental Stress

Science Center Objects

Disease may be caused by infectious agents, nutritional imbalances, physiological or genetically-based abnormalities, and suboptimal environmental conditions, acting either alone or in combination with other factors.  In many instances, environmental stressors may merge forces with an infectious agent or some other non-infectious factor to produce or exacerbate a state of disease.  By studying aquatic wildlife both in their natural habitat and under controlled laboratory conditions, we further our understanding of the many factors and environmental stressors that interact to produce disease in these animals.   This information in turn may help the groups and agencies that manage aquatic animals and their habitats in addressing the sources of stress to better preserve the environment and protect its inhabitants against diseases that threaten these valuable resources.



Water stream

Water quality in streams and rivers may provide a source of environmental stress that influences the occurrence of disease in aquatic life.   Variables such as temperatures, water flow rates, and the presence of nutrients or chemical contaminants may all play an integral role in disease.
(Credit: Christine Densmore, USGS LSC. Public domain.)

Coral reef by Densmore

The coral reef is a prime example of an ecosystem where disease among its many types of aquatic inhabitants has been attributed to potential environmental stressors. 
(Credit: Christine Densmore, USGS LSC. Public domain.)