How common are giant viruses?

For the first time in Finland, researchers have isolated a giant virus — 200 nanometres in diameter, about twice the size of influenza or coronavirus —  which was named Jyvaskylavirus. The discovery shows that giant viruses are more common in northern regions than researchers have thought. It also illustrates that there are still many structures whose origins and functions have not been properly studied. In recent years, giant viruses have been discovered that can be as large as bacteria. These viruses infect amoebas and other microscopic organisms. Most of the giant viruses identified so far have been found in Europe and South America, and their life cycles and distribution are poorly understood.The giant virus, named Jyvaskylavirus, was discovered when environmental samples were mixed with a culture of amoeba Acanthamoeba castellanii. Reseaechers elucidated the genome and structure of the Jyvaskylavirus, which was found to be related to Marseilleviruses previously isolated from France. Other new giant viruses were also detected in environmental samples. New giant virus regulates microbial populations in soil. The finding indicates that giant viruses are more prevalent than thought in soil and water, even in northern environments.