“The current vaccines we have for COVID-19 have played a critical role in reducing morbidity and mortality, but they are not the vaccines that will sustain us in the future with coronavirus infections,” he said.

Osterholm was clear that the roadmap is not meant to confuse readers or dissuade them from getting vaccinated and boosted with current options.

“The current vaccines should be used,” Osterholm said. “But we need to look at vaccines that address more robust immunity, with a broad breadth of protection.”

Though the mRNA vaccines were developed quickly, recent studies have shown that primary series and booster doses do not offer lasting protection beyond 3 to 5 months. Moreover, frequent boosters of the mRNA vaccines has made uptake and public opinion of the vaccines falter.

Osterholm said he compares the current crop of vaccines to the first mobile phones.

“We would not think those phones are satisfactory today,” he explained.

Next threat not if but when

According to the roadmap, animal-to-human spillover events are likely to keep happening with coronaviruses. Both SARS-CoV-1 and MERS-CoV likely originated in bats, the authors of the roadmap write in a commentary in Vaccine, and then later adapted to palm civets (SARS-CoV-1) and dromedary camels (MERS-CoV).

SARS-CoV-2 also likely originated in bats, although the exact origin has yet to be determined. Regardless, researchers have identified more than 500 coronaviruses in bats, which remain the main reservoir for the viruses.

“We can expect that pathogenic coronaviruses will continue to emerge from the bat reservoir or some intermediate animal host in the future,” the authors write.

“We learned from the COVID-19 pandemic that coronaviruses readily cross species, and we also learned that there is a large number of coronavirus in bats,” said Stanley Perlman, MD, PhD, a professor of microbiology and immunology, and pediatrics at the University of Iowa. Perlman was also on the Steering Group for the roadmap. ”Developing a universal vaccine efficacious against all coronaviruses—or even just the subgroup that contains SARS-CoV and SARS-CoV-2—would allow vaccination to begin as soon as transmission across species occurred, or potentially even as part of ongoing vaccination strategies.”

A universal coronavirus vaccine requires research and development endeavors that look at a number of platforms and routes of delivery, Lackritz said.

“Currently we focus on protecting against severe disease and death,” she said. “Maybe we get to the point where we can block transmission.”

Source: New vaccine roadmap eyes future threats of coronaviruses | CIDRAP