‘When will this end?’: How a mutant virus is reshaping scientists’ views of COVID-19

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

Murray until recently had hoped that the discovery of several effective vaccines could help countries gain herd immunity or almost eliminate transmission through a combination of inoculation and previous infection. But last month, data from a vaccine test in South Africa showed not only that a rapidly spreading coronavirus variant could lessen the vaccine’s effect, but it could also escape natural immunity in people who had already been infected.

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

A new consensus is emerging among scientists, according to Reuters interviews with 18 experts who are closely monitoring the pandemic or are working to contain its impact. Many described how the discovery at the end of last year of two vaccines that were about 95% effective against COVID-19 had initially sparked hope that the virus could be largely contained, similar to the way measles has been.

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

As a result, the scientists said, people can expect to continue to take measures such as wearing a routine mask and avoiding crowded places during peaks of COVID-19, especially for people at high risk.

Even after vaccination, “I would still like to wear a mask if there was a variant out there,” said Dr. Anthony Fauci, chief medical advisor to US President Joe Biden, in an interview. “All you need is a little touch of a variant (lighting up) another wave, and there goes your prediction” about when life will return to normal.

Some scientists, including Murray, recognize that the outlook could improve. The new vaccines, which were developed at record speed, still appear to prevent hospitalizations and death, 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 effectiveness against variants. And scientists say there is still a lot to learn about the immune system’s ability to fight the virus.

COVID-19 infection rates have decreased in many countries since the beginning of 2021, with some dramatic reductions in serious illnesses and hospitalizations among the first groups of people to be vaccinated.

WORSE THAN THE FLU

Murray said that if the South African variant, or similar mutants, continued to spread quickly, the number of cases of COVID-19 resulting in hospitalization or death in the coming winter could be four times greater than the flu. The approximate estimate assumes a 65% effective vaccine given to half the population of a country. At worst, this could represent up to 200,000 COVID-19-related deaths in the U.S. during the winter period, based on federal government estimates of annual flu deaths.

Your institute’s current forecast, which runs through June 1, assumes that there will be an additional 62,000 deaths in the U.S. and 690,000 global deaths from COVID-19 by that point. The model includes assumptions about vaccination rates, as well as the transmissibility of South African and Brazilian variants.

The shift in thinking among scientists has influenced more cautious government statements about when the pandemic will end. Britain said last week that it expects a slow emergence from one of the world’s toughest blocks, despite having one of the fastest vaccination initiatives.

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

“What does it mean to pass the emergency phase of this pandemic?” Said Stefan Baral, an epidemiologist at the Johns Hopkins School of Public Health. Although some experts have asked whether countries could completely eradicate any case of COVID-19 through vaccines and severe restrictions, Baral sees the goals as more modest, but still significant. “In my opinion, it is that hospitals are not full, ICUs are not full and people are not passing tragically,” he said.

“SCIENTIFIC WHIPLASH”

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

At the beginning of the pandemic, leading 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.

Still, 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 entirely under control in communities with high rates of inoculation, or the flu, which infects millions of people worldwide every year?

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

A major breakthrough came in November. 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, an efficacy rate that is much higher than any flu vaccine. .

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

“We all felt very optimistic before Christmas about these first vaccines,” said Azra Ghani, chair of infectious disease epidemiology at Imperial College London. “We didn’t necessarily expect that such highly effective vaccines would be possible in that first generation.”

The optimism was short-lived. In late December, the United Kingdom warned of a new, more communicable 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 most rapidly spreading variants in South Africa and Brazil.

Phil Dormitzer, a leading vaccine scientist at Pfizer, told Reuters in November that the success of the American pharmaceutical vaccine signaled that the virus was “vulnerable to immunization” in what he called “an advance for humanity”. In early January, he acknowledged that the variants announced “a new chapter” in which companies will have to constantly monitor for mutations that could lessen the effect of vaccines.

At the end of January, the impact on vaccines became even clearer. Data from the Novavax clinical trial showed that its vaccine was 89% effective in a trial in the UK, but only 50% effective in preventing COVID-19 in South Africa. This was followed, a week later, by data showing that the AstraZeneca PLC vaccine offered limited protection against mild disease 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 for Immunology in San Diego, described it as “scientific whipping”: In December, he believed it was plausible to achieve so-called “functional eradication” of the measles-like coronavirus.

Now, “vaccinating as many people as possible is still the same answer and the same way forward as it was on December 1 or January 1,” said Crotty, “but the expected result is not the same.”