The virus that causes COVID-19 could become no more of a threat than the common cold and circulate seasonally without causing great harm, a study predicts.
But American researchers say the timing would depend on how quickly vaccine programs are rolled out and people develop a level of immunity.
The study published in the journal Science predicts the illness could eventually become less severe each time people caught it, in the same way the four coronaviruses that cause the common cold appear to boost immunity with each sickness.
However a mild-circulating seasonal illness would only happen once the virus was endemic – the point at which spread did not cause massive outbreaks or serious illness.
It comes as global fatalities approach 2 million and nearly 93 million infections, with new mutated strains around the world spreading faster.
The team at Emory University in Georgia and Penn State University based their modelling on studies of six human coronaviruses, four of which regularly spread among people and cause only mild symptoms.
A key result found that in contrast to other infections that can be severe in childhood “CoV-2 could join the ranks of mild, cold-causing endemic human coronaviruses in the long run”.
“A critical prediction is that the severity of emergent CoVs once they reach endemicity depends only on the severity of infection in children.”
Scientists are still learning how long immunity lasts after getting sick but evidence suggests that “infection-blocking immunity” disappears quickly, whereas “disease-reducing immunity is long-lived”.
This means a person can be reinfected with the coronavirus some months after infection but their second, third or fourth time around wouldn’t be as serious – similar to infections with the common cold.
The researchers say once the majority of people gain protection against COVID-19, either through natural infection or vaccination, most cases will occur “almost entirely in babies and young children,” who are known to experience mostly mild illnesses.
“The timing of how long it takes to get to this sort of endemic state depends on how quickly the disease is spreading and how quickly vaccination is rolled out,” study lead author Jennie Lavine, a postdoctoral fellow at Emory University, told the New York Times.
“So really, the name of the game is getting everyone exposed for the first time to the vaccine as quickly as possible.”
Without major vaccine rollouts, it could take many years of infections and deaths before the coronavirus became just another seasonal illness, the researchers said.
The COVID-19 vaccines are also not 100 per cent effective at preventing infection, so it’s likely the jab will be better at preventing severe disease in the long run.
Even in the event new coronavirus strains reappear during the endemic phase, like the one from the UK that is now spreading in other countries, the researchers say immunity gained from previous strains “is nonetheless strong enough to prevent severe disease”.
Race to stop new COVID strains
Australian authorities are racing to find ways to stop new strains of the coronavirus from spreading among our population before it’s too late.
And the emerging threat is dividing state and territory leaders.
It comes after six people tested positive for the highly contagious UK strain at Brisbane’s Grand Chancellor quarantine hotel, which has now been shut down.
Although there is no evidence to suggest the variant is more deadly than others, scientists believe it could be up to 70 per cent more transmissible.
Given the chance, this new strain could rapidly spread among the community and ruin our winning streak against the pandemic.
Australia recorded no local transmission of coronavirus on Thursday.
To manage the threat of the UK strain, Queensland Premier Annastacia Palaszczuk has proposed a national network of outback quarantine camps to protect Australians.
She said it’s clearly too risky to quarantine travellers in capital cities any more, and will raise the issue at the next national cabinet meeting on January 22.
Under the proposal, returned travellers would undergo their two weeks’ quarantine at vacant regional mining camps.
However, the idea has fallen flat in NSW and WA.
NSW Health Minister Brad Hazzard said it would not be feasible for the 3500 staff working in the state’s hotel quarantine system to be moved to regional camps.
“On the basis of less than, I think, three incidences now over the last year, it would not be logical for us to move that arrangement out of Sydney,” he told reporters in Sydney.
Meanwhile, WA Premier Mark McGowan has snubbed Queensland’s plan, but for an entirely different reason.
He wants to use immigration detention centres like Christmas Island.
“Clearly with the British strain, that’s something we should reconsider,” he said.
“Those facilities are available and there are experienced staff that can deal with these matters.”
Victorian Premier Daniel Andrews said he had no plans to change his state’s quarantine system but acknowledged limits on CBD hotels.
It came as the state recorded no new coronavirus infections in the community or in hotel quarantine, on the eighth straight day without locally acquired cases in the state.
As a result, Victoria’s chief health officer has deemed it safe for workers to return to offices from next week, after an outbreak over the new year period paused the return to workplaces.
From Monday, the Victorian public service will return to the office at 25 per cent capacity and other workplaces can increase to 50 per cent.
From midnight on Sunday, mandatory mask rules will be eased to pre-Christmas rules.
That means masks remain mandatory on flights, public transport, taxis and ride-sharing vehicles supermarkets and big indoor shopping centres.
They will no longer be compulsory in offices, but it is recommended they be worn where physical distancing isn’t possible.