REEDVILLE, Va. (WRIC) — An essential aspect of dolphin social structure is their friendly, close contact. However this intimate social interaction has led to the spread of a virus among Virginia dolphins, according to marine-life specialists.

Scientists are currently tracing dolphin social networks in the Potomac River and the Chesapeake Bay to track a highly contagious and lethal virus.

Cetacean morbillivirus is one of the greatest threats to dolphin and whale communities worldwide, and it is currently spreading among East Coast dolphins.

The playful and friendly nature of dolphin communities means they can spread the virus more easily as they share space and air so closely.

A dolphin leaps into the air in the Potomac river (Ann-Marie Jacoby/Potomac-Chesapeake Dolphin Project via AP).

Human disruptions to dolphin habitats also weaken these marine mammals’ immune systems, leaving them more vulnerable to such diseases. These disruptions include chemical and plastic pollution, warming water temperatures and boat noise.

This story was written using reporting by The Associated Press.