What biotic and abiotic factors control viral activity in the sea

The abiotic and biotic factors that control viral activity at sea are:  Sunlight, presence of bacteria, presence of eukaryotic microorganisms and presence of suspended particles.

Explanation:

As you already know, viruses are obligatory acellular particles and tiny parasites. They can be present in different environments, including the sea, where they can establish viral activity in different environments.

Viruses are composed of a nucleic acid molecule and a protein coat. This nucleic acid is highly changeable, being able to modify the viral activity of several forms.

Under the sea the main factors that can cause these mutations that modify viral activity are:

the cell theory states that all living things including animals, as well as plants, are made of cells.