Dr. Francis Collins, director of the National Institutes of Health, made the announcement, in which he outlined a new framework for the controversial research. The work with three viruses can now go forward, but only if a scientific review panel determines that the benefits outweigh the risks.
"We have a responsibility to ensure that research with infectious agents is conducted responsibly, and that we consider the potential biosafety and biosecurity risks associated with such research," Collins said in a statement
The government paused the research in 2014 to review the practices in handling and storing infectious agents. At the time, Collins said that biosafety and biosecurity risks needed to be "understood better."
The pause came after several incidents involving the mishandling of potentially dangerous pathogens at government laboratories.
The US Centers for Disease Control and Prevention accidentally exposed dozens of workers
to anthrax in 2014, and a subsequent investigation detailed other instances in which lab workers did not follow protocol. Around that time, vials of the deadly smallpox virus were found in a cardboard box in an unsecured refrigerator at the National Institutes of Health's campus in Bethesda, Maryland.
In Tuesday's announcement, the institutes said that approved research would take place only if the researcher and institution where the research is being conducted demonstrate the "capacity and commitment to conduct it safely and securely, and have the ability to respond rapidly" should things go wrong.
It also said that the research must be "ethically justifiable" and that any pathogen created, transferred or used in the research "must be reasonably judged to be a credible source of a potential future human pandemic."
Dr. Tom Frieden, who was the director of the CDC from 2009 to 2017, applauded Tuesday's decision, saying such studies "help scientists better understand how dangerous organisms work, with the ultimate goal of learning how to stop them."
"There's benefit to be gained from this research, but only if lab safety is a top priority and limited to a small group of highly trained staff," said Frieden, who now serves as president and CEO of the initiative Resolve to Save Lives.