Scientists Discover 100,000 Viruses Never Seen Before

Scientists have identified more than 100,000 RNA viruses that have never been seen before, a new study has revealed.

An international team of researchers has discovered novel and diverse groups of RNA viruses that infect bacteria, according to a study published in the journal Cell. They said the research has increased the number of known RNA viruses ninefold.

The experts also uncovered genes that have never been seen before in any RNA virus and had only previously been detected in DNA viruses or cellular life.

RNA viruses are those in which the genetic material is RNA (ribonucleic acid)—a compound present in all living cells that has structural similarities to DNA. They include the coronavirus and influenza viruses, as well as dengue and West Nile virus, among others.

The latest discovery could aid the development of treatments against antibiotic-resistant pathogens, as well as defenses against agriculturally harmful bacteria, fungi and pests, the researchers said.

The aim of the Cell study was to expand scientific knowledge of RNA viruses in the environment, which are "extremely" understudied, Uri Gophna of the Shmunis School of Biomedicine and Cancer Research in the Wise Faculty of Life Sciences at Tel Aviv University, Israel, told Newsweek.

"Nearly all RNA viruses that were studied to date are pathogens important for human health and agriculture, but we knew there has to be large RNA virus diversity that remained unexplored," Gophna, a lead researcher on the paper, said.

For the study, the international team analyzed publicly available data generated by more than one hundred labs all over the world at different times that studied different environments ranging from soil, through marine to man-made, such as waste treatment plants, among other ecosystems.

The researchers identified roughly 110,000 previously unknown RNA viruses, even identifying which organisms they are likely to infect. Most of them are not suspected to infect animals but rather bacteria, algae, fungi and protists—a group of primarily single-celled, microscopic organisms.

"We show that viruses from the same broad groups can often also infect widely different organisms," Gophna said.

While some viruses can infect humans and cause disease, the vast majority are not harmful to us. Those that infect bacterial cells are among the most common.

"Most of the viruses that we have discovered pose little threat to animals and certainly humans," Gophna said. "On the contrary, having access to many novel viruses that infect bacteria, can provide us with a future arsenal against antibiotic-resistant pathogens."

The researcher mentioned that two other "impressive" RNA virus discovery efforts had been published previously this year.

"While they were not as comprehensive as our work, and discovered fewer viruses, and much fewer virus functions, they are of a similar scale to ours," he said.