The Swiss Army Vaccine

There are promising signs that a single vaccine could protect against multiple coronaviruses and variants. But with pharma companies invested in boosters, will anyone pay to develop it?

- Robert Langreth

As Covid-19 began spreading in early 2020, one of Linfa Wang’s first ideas was to test the blood of people who’d survived a previous coronavirus outbreak. The virologist, who works out of Duke-NUS Medical School, a collaboration between Duke and the National University of Singapore, has been studying bat-borne viruses for decades. He’d helped show that SARS-CoV-1, which killed almost 800 people in 2003, likely jumped to humans from horseshoe bats. Wang’s new theory was that people who’d recovered from the original SARS might harbor antibodies that could help fight the new one, SARS-CoV-2.

Initially, the experiment was a bust. The patients Wang tested had antibodies only against the older version of SARS. But as a number of Covid variants began spreading early this year, he decided to test the patients again. By this point, many of the Singaporean SARS survivors had also been vaccinated against Covid, providing a rare set of immune systems that had been exposed to proteins from these related coronaviruses.

What Wang found astonished him. After getting the Covid shot, the SARS patients had developed something akin to super-antibodies, which blocked both SARS viruses and a multitude of other coronaviruses. All eight patients had anti bodies that, in test-tube experiments, neutralized five different bat and pangolin coronavirus strains that had never infected humans. The results, published in the New England Journal of Medicine in August, offered one of the strongest bodies of evidence that a universal coronavirus vaccine is possible.