Virus may never go away but could change into mild annoyance
NEW DELHI — What if COVID-19 never goes away?
Experts say it's likely that some version of the disease will lin ger for years. But what it will look like in the future is less clear.
Will the corona virus, which has already killed more than 2 million people worldwide, eventually be eliminated by a global vaccination campaign, like smallpox? Will dangerous new variants evade vaccines? Or will the virus stick around for a long time, transforming into a mild annoyance, like the common cold?
Eventually, the virus known as SARS-CoV-2 will become yet “another animal in the zoo ,” joining the many other infectious diseases that humanity has learned to live with, predicted Dr. T. Jacob John, who studies viruses and was at the helm of India's efforts to tackle polio and HIV/ AIDS.
But no one knows for sure. The virus is evolving rapidly, and new variants are popping up in different countries. The risk of these new variants was underscored when Novavax Inc. found that the company's vaccine did not work as well against mutated versions circulating in Britain and South Africa. The more the virus spreads, experts say, the more likely it is that a new variant will become capable of eluding current tests, treatments and vaccines.
For now, scientists agree on the immediate priority: Vaccinate as many people as quickly as possible. The next step is less certain and depends largely on the strength of the immunity offered by vaccines and natural infections and how long it lasts.
“Are people going to be frequently subject to repeat infections? We don't have enough data yet to know,” said Jeffrey Shaman, who studies viruses at Columbia University. Like many researchers, he believes chances are slim that vaccines will confer lifelong immunity.
If humans must learn to live with COVID-19, the nature of that coexistence depends not just on how long immunity lasts, but also how the virus evolves. Will it mutate significantly each year, requiring annual shots, like the flu? Or will it pop up every few years?
This question of what happens next attracted Jennie Lavine, a virologist at Emory University, who is co-author of a recent paper in Science that projected a relatively optimistic scenario: After most people have been exposed to the virus — either through vaccination or surviving infections—the pathogen“will continue to circulate, but will mostly cause only mild illness,” like a routine cold.
While immunity acquired from other corona viruses—like those that cause the common cold or SARS or MERS — wanes over time, symptoms upon reinfection tend tobe milder than the first illness, said Ottar Bjornstad, a co-author of the Science paper who studies viruses at Pennsylvania State University.
“Adults tend not to get very bad symptoms if they've already been exposed,” he said.
The prediction in the Science paper is based on an analysis of how other coronaviruses have behaved over time and assumes that SAR-CoV-2 continues to evolve, but not quickly or radically.
The 1918 flu pandemic could offer clues about t he course of COVID19. That pathogen was an H1N1 virus with genes that originated in birds, not a coronavirus.