COVID-19 has highlighted the need for a universal vaccine that remains effective against all variants of a virus family. In their review, published today in Cell Host and Microbe, scientists from Duke-NUS and their collaborators assess the progress made in the development of such vaccines against three virus families that pose a high risk of triggering Disease X: henipaviruses, influenza viruses and coronaviruses.
“Viruses from these three families mutate frequently, thrive in many different species of wild animals and can range from mild to fatal,” says Professor Wang Linfa, the senior author of the review who has been studying ways to develop a broadly protective pan-sarbecovirus vaccine.
Reviewing the development of vaccines and monoclonal antibodies against the three viral threats, Wang and his co-authors, including Dr Tan Chee Wah, draw out four lessons:
- No one vaccine platform reigns supreme: the effectiveness of a vaccine depends on the virus, natural reservoirs, the extent of mutations and the level of immunity required to remain protected.
- Successful development depends on knowledge accumulated over decades: scientists had already developed the mRNA platform and studied the Spike protein extensively before the pandemic hit.
- Broadly neutralising antibodies have been isolated for each of the three virus families: despite this, no vaccines have resulted from these discoveries yet, and more work is needed to reverse engineer an effective vaccine from these.
- Neutralising monoclonal antibodies against viruses with high pandemic potential could be used as a first-line containment strategy in a new outbreak: though costly, this could mitigate outbreaks while the development of family-wide vaccines remains ongoing.
“We are working on a third-generation COVID vaccine that could protect against sarbecoviruses, the subgroup of coronaviruses that includes SARS-CoV and SARS-CoV-2,” says Tan, who is a senior research fellow in Wang’s lab and the first author of the review paper.
“While a pan-sarbecovirus vaccine seems possible,” says Wang, “a vaccine that targets even broader groups of coronaviruses — a real ‘dream vaccine’ — remains elusive at the moment.
“But what is most important is that we continue to invest in finding a solution now so that we can react quicker when Disease X strikes. We need a paradigm shift to make vaccine development proactive or pre-emptive rather than reactive as we used to do.”