After the anthrax scare in 2001, Annie Jacobsen explains (in Biological War), gain-of-function research quickly became normalized within government-funded science:
Agencies such as the National Institutes of Health and the National Institute of Allergy and Infectious Diseases funded this kind of experimental research with gusto, not just in labs across America, but also in BSL-3 and BSL-4 labs overseas, including in places like Wuhan, China.
“The benefits of such [gain-of-function] experiments and the resulting knowledge outweigh the risks,” argued Dr. Anthony Fauci in a 2012 paper. Fauci served as the director of the National Institute of Allergy and Infectious Diseases at the time. During the Covid pandemic, he served as chief medical advisor to Presidents Donald Trump and Joe Biden.
Critics of gain-of-function cried foul, citing the Australian mousepox experiment of 2001 and the H5N1 ferret flu experiments conducted in the Netherlands and the United States in 2011–2012 as examples of all that could go wrong. In the mousepox experiment, a relatively simple genetic tweak inadvertently turned a mild virus into a weapon that killed previously vaccinated host mice, proving the nightmare reality that gain-of-function can easily erase existing immunity. In the H5N1 ferret flu experiments, scientists took one of the deadliest influenza viruses ever observed in humans and taught it to spread through the air, demonstrating how a pandemic-causing airborne pathogen can be easily engineered in a lab.
[…]
In 2014, the Obama administration imposed a temporary federal pause on certain gain-of-function studies.
[…]
Gain-of-function was reclassified under a new term known as “Potential Pandemic Pathogen Care and Oversight,” or P3CO, shifting the debate from prohibition to risk management.
[…]
And then came the Covid pandemic, thrusting gain-of-function experiments into the global spotlight. As facts emerged, millions of people began to question whether Covid’s SARS-CoV-2 virus arose naturally, from bats, or had been genetically engineered in Wuhan’s secretive BSL-3 and BSL-4 labs.
[…]
Governments around the world continue to fund this kind of high-risk research today, almost always with the same central argument in play. That worst-case-scenario pathogen experiments conducted inside a BSL-3 or BSL-4 lab are essential to preventing a worst-case-scenario incident or attack from happening in the real world.
[…]
A 2025 global survey identified 110 BSL-4 labs in thirty-four countries and 3,515 BSL-3 labs across 149 countries, possibly more.