As described in a paper in Nature Immunology1 this month, an international team of scientists has launched a global hunt for people who are genetically resistant to infection with the pandemic virus. The team hopes that identifying the genes protecting these individuals could lead to the development of virus-blocking drugs that not only protect people from COVID-19, but also prevent them from passing on the infection.

“It’s a terrific idea,” says Mary Carrington, an immunogeneticist at the Frederick National Laboratory for Cancer Research in Bethesda, Maryland. “Really, a wise thing to do.”

But success isn’t guaranteed. If genetic resistance to the coronavirus SARS-CoV-2 exists, there may be “only a handful” of people with this trait, says Isabelle Meyts, a paediatric immunologist and physician at the Catholic University of Leuven in Belgium, who is part of the consortium behind the effort.

“The question is how to find those people,” says Sunil Ahuja, an infectious-diseases specialist at the University of Texas Health Science Center at San Antonio. “It’s very challenging. This is not for the faint of heart.”