European eels transmit herpesvirus through biting behavior

Biting spreads virus efficiently

A team from the University of Liège demonstrated that viruses infecting fish are not transmitted exclusively through water. A group led by professor Alain Vanderplasschen showed the AngHV-1 herpesvirus spreads very efficiently through biting during aggressive interactions. This finding, which appeared in the Journal of Virology, contests a broadly held tenet within aquatic virology. The European eel is currently classified as critically endangered with populations declining dramatically over recent decades.

Virus causes skin lesions

The virus is capable of creating hemorrhagic lesions on both the skin and gills of infected animals. Mortality rates reach up to 30 percent in intensive aquaculture facilities where conditions are crowded. Researchers altered the virus genetically to include a firefly enzyme, causing it to emit light. This technique allowed them to track infection progression within the animal's body using specialized equipment.

Social interactions drive spread

Experiments showed that a single contact involving biting is sufficient to transmit the virus from infected to uninfected eels. Across each of the three situations reviewed, any animal that faced exposure contracted an illness following the occurrence of such violent actions. Even hostile social encounters may decisively influence how viruses disperse within water habitats. Its life cycle includes moving thousands of kilometers from the Atlantic Ocean to European inland waters.