• More and more physicians and public health officials are warning that even with the mass rollout of vaccines, Covid may become endemic.
• The mass delivery of vaccines started in many high-income countries almost two months ago and has since been gathering pace, but the mass immunization of populations will take time.
• Some low-income countries have not received a single dose of vaccine to protect people most at risk from the coronavirus.                          More and more physicians and public health officials are warning that even with the mass rollout of safe and effective vaccines, Covid may permanently establish itself.   White House coronavirus advisor Dr. Anthony Fauci, Moderna CEO Stephane Bancel and World Health Organization executive director of the Health Emergencies Program Dr. Mike Ryan have said in recent weeks that the coronavirus may never go away.

To date, more than 107 million people worldwide have contracted Covid-19, with 2.36 million deaths, according to data compiled by Johns Hopkins University.

David Heymann, professor of infectious disease epidemiology at the London School of Hygiene and Tropical Medicine, warned in October that the virus appeared to be on course to become endemic. He reaffirmed his position this week during a webinar for think tank Chatham House.

"I think if you speak with most epidemiologists and most public health workers, they would say today that they believe this disease will become endemic, at least in the short term and most likely in the long term," he said.

Heymann is the chair of the WHO's strategic and technical advisory group for infectious hazards and led the U.N. agency's infectious disease unit during the SARS epidemic in 2002-2003.

Heymann cautioned that it was not yet possible to be sure of the virus's destiny since its outcome depends on many unknown factors.

"Right now, the emphasis is on saving lives, which it should be, and on making sure that hospitals are not overburdened with Covid patients — and this will be possible moving forward," Heymann said, citing the mass rollout of vaccines.

'Need to learn lessons from 2020'

The mass delivery of Covid vaccines started in many high-income countries almost two months ago and has been gathering pace, but the mass immunization of populations will take time.

Some low-income countries, however, have not received a single dose of vaccine to protect people most at risk from the coronavirus.

A report published by the Economist Intelligence Unit last month projected that the bulk of the adult population of advanced economies would be vaccinated by the middle of next year. In contrast, however, this timeline extends to early 2023 for many middle-income countries and even as far out as 2024 for some low-income countries.

It underscores the scale of the challenge to bring the pandemic under control around the world.

"Covid-19 is an endemic human infection. The scientific reality is that, with so many people infected worldwide, the virus will continue to mutate," said Dr. Jeremy Farrar, director of Wellcome and a member of the UK.'s Scientific Advisory Group for Emergencies.

"Living with this virus does not, however, mean we cannot control it. We need to learn lessons from 2020 and act swiftly. Every day counts," he added.

Balancing our living with endemic diseases

"I think it is good to put this in context and think about the other infectious diseases that are endemic today," Heymann said during an online event Wednesday, when asked whether policymakers should be mindful of other endemic diseases in responding to the Covid pandemic.

He cited tuberculosis and HIV, as well as four endemic coronaviruses that are known to cause the common cold.

"We have learned to live with all of these infections, we've learned how to do our own risk assessments. We have got vaccines for some, we have therapeutics for others, we have diagnostic tests that can help us all do a better job of living with these infections."

"There are a couple of unknowns that make it very difficult for political leaders and public health leaders to make decisions as to what would be the best strategies, including the fact that we don't completely understand 'long Covid' and its impact or its occurrence after even very minor infections," he continued.

"So, it is not a matter of this being a special disease. This is one of many that we will have to balance our living with and understand how to deal with it as we do influenza, as we do with other infections," Heymann said.

The term "long Covid" refers to patients suffering from prolonged illness after initially contracting the virus, with symptoms including shortness of breath, migraines and chronic fatigue.

Public discourse on the pandemic has largely focused on those with a severe or fatal illness, whereas ongoing medical problems as a result of the virus are often either underappreciated or misunderstood.

Last month, the largest global study of long Covid to date found that many of those suffering with lingering effects had been unable to return to work at full capacity six months later.

CNBC