Coronavirus : Covid-19 Hopes for ‘Herd Immunity’ Fade as Virus Hurtles Toward Becoming Endemic

Dr. Anthony Fauci says indoor mask guidance can ease as vaccinations rise. The E.U.’s immunization drive is speeding up after lagging for months.

Here’s what you need to know:

The world may need to learn to live with the virus.
Fauci says indoor mask guidance should ‘start being more liberal.’
Vaccinations are rising in the European Union after a long, slow start.
Turkey’s second major wave has begun to recede, though its lockdown is far from tight.
A potentially fatal fungal infection is cropping up among India’s Covid patients.
Spain ended its state of emergency, and streets erupted in celebrations.
U.S. states are turning down hundreds of thousands of doses as demand plummets.
Some U.S. families are not eager to send their children back to school.
Early in the pandemic, there was hope that the world would one day achieve herd immunity, the point when the coronavirus lacks enough hosts to spread easily. But over a year later, the virus is crushing India with a fearsome second wave and surging in countries from Asia to Latin America.
Experts now say it is changing too quickly, new more contagious variants are spreading too easily and vaccinations are happening too slowly for herd immunity to be within reach anytime soon.
That means if the virus continues to run rampant through much of the world, it is well on its way to becoming endemic, an ever-present threat.
Virus variants are tearing through places where people gather in large numbers with few or no pandemic protocols, like wearing masks and distancing, according to Dr. David Heymann, a professor of infectious disease epidemiology at the London School of Hygiene and Tropical Medicine.
While the outbreak in India is capturing the most attention, Dr. Heymann said the pervasive reach of the virus means that the likelihood is growing that it will persist in most parts of the world.
As more people contract the virus, developing some level of immunity, and the pace of vaccinations accelerates, future outbreaks won’t be on the scale of those devastating India and Brazil, Dr. Heymann said. Smaller outbreaks that are less deadly but a constant threat should be expected, Dr. Heymann said.
“This is the natural progression of many infections we have in humans, whether it is tuberculosis or H.I.V.,” said Dr. Heymann, a former member of the Epidemiology Intelligence Service at the Centers for Disease Control and Prevention and a former senior official at the World Health Organization. “They have become endemic and we have learned to live with them and we learn how to do risk assessments and how to protect those we want to protect.”
A CLOSER LOOK
Coronavirus World Map: Tracking the Global Outbreak
Vaccines that are highly effective against Covid were developed rapidly, but global distribution has been plodding and unequal. As rich countries hoard vaccine doses, poorer countries face big logistical challenges to distributing the doses they manage to get and vaccine hesitancy is an issue everywhere. And experts warn the world is getting vaccinated too slowly for there to be much hope of ever eliminating the virus.
Only two countries have fully vaccinated more than half of their populations, according to the Our World in Data project at the University of Oxford. They are Israel and the East African nation of the Seychelles, an archipelago with a population of fewer than 100,000. And just a handful of other countries have at least partially vaccinated nearly 50 percent or more, including Britain, tiny Bhutan, and the United States.
Less than 10 percent of India’s vast population is at least partly vaccinated, offering little check to its onslaught of infections.
In Africa, the figure is slightly more than 1 percent.
Still, public health experts say a relatively small number of countries, mostly island nations, have largely kept the virus under control and could continue keeping it at bay after vaccinating enough people.
New Zealand, through stringent lockdowns and border closures, has all but eliminated the virus. Dr. Michael Baker, an epidemiologist at the University of Otago who helped devise the country’s coronavirus response, said New Zealand would likely achieve herd immunity by immunizing its population, but it has a long way to go with only about 4.4 percent of New Zealanders at least partially vaccinated.
“All of the surveys show there is a degree of vaccine hesitancy in New Zealand, but also a lot of people are very enthusiastic,” Dr. Baker said. “So I think we will probably get there in the end.”
While new daily cases have remained at near-world record levels, the number of deaths has dropped fro

Credit...Jacob Moscovitch for The New York Times
Dr. Anthony S. Fauci said on Sunday that he was open to relaxing indoor masking rules as more Americans are vaccinated against the virus, just two days after the Centers for Disease Control and Prevention belatedly emphasized the danger of airborne transmission.
Dr. Fauci, President Biden’s chief medical adviser for the pandemic, said that as vaccinations climb, “we do need to start being more liberal” in terms of rules for wearing masks indoors, though he noted that the nation was still averaging about 43,000 cases of the virus daily. “We’ve got to get it much, much lower than that,” he said.
On Friday, the C.D.C. updated its guidance about how the coronavirus spreads, stating explicitly that people could inhale airborne virus even when they were more than six feet away from an infected individual. Previously, the agency had said that most infections were acquired through “close contact, not airborne transmission.”
The update brought the agency in line with evidence of the danger from airborne droplets that epidemiologists had noted as the pandemic unfolded last year. According to some experts, it also underscored the urgency for the federal Occupational Safety and Health Administration to issue standards for employers to address potential airborne hazards in the workplace.
Dr. Fauci’s comments on Sunday came in response to a question about comments that Dr. Scott Gottlieb, the former head of the Food and Drug Administration, made last week on CNBC. Dr. Gottlieb said that relaxing indoor mask mandates now — “especially if you’re in environments where you know you have a high level of vaccination” — would give public health officials “the credibility to implement them” again in the fall or winter if cases surge.
Dr. Fauci, asked by George Stephanopoulos on ABC’s Sunday program “This Week” whether he agreed, said: “I think so, and I think you’re going to probably be seeing that as we go along, and as more people get vaccinated.”
“The C.D.C. will be, almost in real time, George, updating their recommendations and their guidelines,” Dr. Fauci continued. “But yes, we do need to start being more liberal as we get more people vaccinated.”
Over a third of the U.S. population — more than 112 million people — is fully vaccinated and another 40 million people have received the first dose of a two-dose protocol.
The C.D.C., which issues national guidance on masking, says that even vaccinated people should continue to wear masks in indoor public spaces, including restaurants when they are not actively eating and drinking. In many places across the country, it is clear that the guidance is not being followed.
In a separate interview on Sunday, on CNN’s “State of the Union,” Jeffrey Zients, Mr. Biden’s Covid response coordinator, was somewhat more circumspect than Dr. Fauci when asked about Dr. Gottlieb’s comments.
“I think everyone is tired, and wearing a mask is — it can be a pain,” Mr. Zients said. “But we’re getting there. And the light at the end of the tunnel is brighter and brighter. Let’s keep up our guard. Let’s follow the C.D.C. guidance. And the C.D.C. guidance across time will allow vaccinated people more and more privileges to take off that mask.”
Mr. Zients also suggested that instead of reaching herd immunity — the point when enough people are immune to the virus that it can no longer spread through the population — the goal should be to achieve some sense of normalcy by getting 70 percent of Americans immunized. President Biden has called for 70 percent to have at least one dose by July 4.
Reaching 70 percent will create “a pattern of decreasing cases, hospitalizations and deaths and take us down to a sustainable low level,” Mr. Zients said, pointing to Israel, a world leader in vaccinations, as a model.
In that country, vaccinations have reached almost 60 percent of the population since they began on Dec. 19 last year, and the seven-day average of new cases has dropped from a high of more than 8,600 on Jan. 17 to fewer than 60 as of Saturday.