“When will it end?”: How a changing virus is reforming scientists ’opinions about COVID-19

CHICAGO (Reuters) – Chris Murray, a disease expert at the University of Washington whose projections cause COVID-19 infections and deaths worldwide, is changing his assumptions about the course of the pandemic.

Until recently, Murray hoped that the discovery of several effective vaccines would help countries achieve herd immunity or nearly eliminate transmission through a combination of inoculation and previous infection. But in the last month, data from a vaccine trial in South Africa showed not only that a rapidly spreading variant of the coronavirus could dampen the effect of the vaccine, but could also elude the natural immunity of people who had been previously infected.

“I couldn’t sleep” after seeing the data, Murray, a director of the Seattle-based Institute of Health Metrics and Assessment, told Reuters. “When will it end?” he wondered, referring to the pandemic. It is currently updating its model to take into account the ability of variants to escape natural immunity and expects to offer new projections as early as this week.

A new consensus is emerging among scientists, according to Reuters interviews with 18 specialists who are closely following the pandemic or working to curb its impact. Many described how the advance at the end of last year of two vaccines with 95% efficacy against COVID-19 had initially sparked hope that the virus could be contained to a large extent, in the same way that it has been measles.

But, they say, data in recent weeks on new variants from South Africa and Brazil have diminished that optimism. They now believe that SARS-CoV-2 will not only stay with us as an endemic virus, it will continue to circulate in communities, but will likely cause a significant burden of disease and death over the next few years.

As a result, scientists said, people could expect to continue taking steps such as using mask routines and avoiding crowded places during COVID-19 surges, especially for high-risk people.

Even after vaccination, “I would still want to wear a mask if there was a variant,” Dr. Anthony Fauci, chief medical adviser to U.S. President Joe Biden, said in an interview. “All you need is a little blow from a variant (which causes) another wave, and here goes your prediction” about when life returns to normal.

Some scientists, including Murray, recognize that the outlook could improve. New vaccines, developed at a record rate, still appear to prevent hospitalizations and deaths, even when new variants are the cause of the infection. Many vaccine developers are working on booster vaccines and new inoculations that can preserve a high level of efficacy against variants. And, according to scientists, much remains to be learned about the immune system’s ability to fight the virus.

Already, COVID-19 infection rates have declined in many countries since early 2021, with some drastic reductions in serious illnesses and hospitalizations among the first groups of people vaccinated.

WORSE THAN THE DEGREE

Murray said that if the South African variant or similar mutants continue to spread rapidly, the number of COVID-19 cases causing hospitalization or death over the next winter could be four times higher than the flu. The approximate estimate is an effective 65% vaccine given to half the population of a country. At worst, this could account for up to 200,000 COVID-19-related deaths in the United States during the winter period, according to federal government estimates of annual fatalities from influenza.

His institute’s current forecast, which runs through June 1, estimates there will be an additional 62,000 deaths in the United States and 690,000 worldwide deaths from COVID-19 at this time. The model includes assumptions about vaccination rates, as well as the transmissibility of the South African and Brazilian variants.

The shift in thinking among scientists has influenced the most cautious government statements about when the pandemic will end. Last week, Britain said it expects a slow emergency from one of the world’s tightest closures, despite having one of the fastest vaccination mechanisms.

U.S. government predictions of a return to a more normal lifestyle have been repeatedly pushed back, most recently from late summer to Christmas and then to March 2022. Israel issues immunity documents “Green Pass ”To people who have recovered from COVID-19 vaccinated, allowing them to return to hotels or theaters. The documents are only valid for six months because it is not clear how long the immunity will last.

“What does it mean to move from the emergency phase of this pandemic?” Said Stefan Baral, an epidemiologist at the Johns Hopkins School of Public Health. While some experts have questioned whether countries could completely eradicate any case of COVID-19 through vaccines and strict closures, Baral considers the targets more modest, but still significant. “In my opinion, it’s that the hospitals aren’t full, the ICUs aren’t full and people don’t tragically go through,” he said.

“SCIENTIFIC WHIPLASH”

From the beginning, the new coronavirus has been a moving target.

Early in the pandemic, prominent scientists warned that the virus could become endemic and “may never go away,” including Dr. Michael Ryan, head of the World Health Organization’s emergency program.

However, they had a lot to learn, including whether it would be possible to develop a vaccine against the virus and how quickly it would mutate. Would it be more like measles, which can be kept almost at bay in communities with high rates of inoculation or flu, which infects millions of people each year worldwide?

For much of 2020, many scientists were surprised and assured that the coronavirus had not changed significantly enough to be more transmissible or deadly.

In November there was a breakthrough. Pfizer Inc. and its German partner BioNTech SE, as well as Moderna Inc., said their vaccines were about 95% effective in preventing COVID-19 in clinical trials, a much higher rate of efficacy than any vaccine against the flu.

At least some of the scientists interviewed by Reuters said that even after these results, they did not expect the vaccines to end the virus. But many told Reuters that the data made the scientific community expect that it would be possible to virtually eliminate COVID-19, if only the world could be vaccinated quickly enough.

“We all felt pretty optimistic before Christmas with these first vaccines,” said Azra Ghani, president of infectious disease epidemiology at Imperial College London. “We didn’t necessarily expect these high-efficiency vaccines to be possible in this first generation.”

Optimism proved ephemeral. In late December, the UK warned of a new, more transmissible variant that was fast becoming the dominant form of coronavirus in the country. At the same time, the researchers learned about the impact of the variants that are spreading most rapidly in South Africa and Brazil.

Phil Dormitzer, a top-notch vaccine scientist at Pfizer, told Reuters in November that the success of the U.S. drug maker’s vaccine indicated the virus was “vulnerable to vaccination” in what he called “an advance for humanity.” In early January, he acknowledged that the variants heralded “a new chapter” in which companies will have to constantly monitor for mutations that could dampen the effect of vaccines.

In late January, the impact on vaccines became even clearer. Data from Novavax clinical trials showed that their vaccine was 89% effective in a trial in the UK, but only 50% in the prevention of COVID-19 in South Africa. A week later, data followed showing that the AstraZeneca PLC vaccine offered only limited protection against mild diseases against the South African variant.

The most recent change of opinion was considerable, several scientists told Reuters. Shane Crotty, a virologist at the La Jolla Institute of Immunology in San Diego, described it as a “scientific whiplash”: in December he thought it was plausible to achieve the so-called “functional eradication” of coronavirus, similar to measles.

Now, “vaccinating as many people as possible is still the same response and the same path toward Dec. 1 or Jan. 1,” Crotty said, “but the expected outcome is not the same.”