The changing virus is reshaping scientists’ views
CHICAGO — Chris Murray, a University of Washington disease expert whose projections on COVID-19 infections and deaths are closely followed worldwide, is changing his assumptions about the course of the pandemic.
Murray had until recently been hopeful that the discovery of several effective vaccines could 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 coronavirus variant could dampen the effect of the vaccine, it could also evade natural immunity in people who had been previously infected.
“I couldn’t sleep” after seeing the data, Murray, director of the Seattle-based Institute for Health Metrics and Evaluation, told Reuters. “When will it end?” he asked himself, referring to the pandemic.
He is currently updating his model to account for variants’ ability to escape natural immunity and expects to provide new projections as early as this week.
A new consensus is emerging among scientists, according to Reuters interviews with 18 specialists who closely track the pandemic or are working to curb its impact. Many described how the breakthrough late last year of two vaccines with around 95 per cent efficacy 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 in recent weeks on new variants from South Africa and Brazil has undercut that optimism. They now believe that SARSCOV-2 will not only remain with us as an endemic virus, continuing to circulate in communities, but will likely cause a significant burden of illness and death for years to come.
As a result, the scientists said, people could expect to continue to take measures such as routine mask-wearing and avoiding crowded places during COVID-19 surges, especially for people at high risk.
Even after vaccination, “I still would want to wear a mask if there was a variant out there,” Dr. Anthony Fauci, chief medical advisor to U.S. President Joe Biden, said in an interview. “All you need is one little flick of a variant (sparking) another surge, and there goes your prediction” about when life gets back to normal.
Some scientists, including Murray, acknowledge that the outlook could improve. The new vaccines, which have been developed at record speed, still appear to prevent hospitalizations and death even when new variants are the cause of infection. Many vaccine developers are working on booster shots and new inoculations that could preserve a high level of efficacy against the variants. And, scientists say there is still much to be learned about the immune system’s ability to combat the virus.
Already, COVID-19 infection rates have declined in many countries since the start of 2021, with some dramatic reductions in severe illness and hospitalizations among the first groups of people to be vaccinated.
Murray said, if the South African variant, or similar mutants, continue to spread rapidly, the number of COVID-19 cases resulting in hospitalization or death this coming winter could be four times higher than the flu. The rough estimate assumes a 65 per cent effective vaccine given to half of a country’s population. In a worst-case scenario, that could represent as many as 200,000 U.S. deaths related to COVID-19 over the winter period, based on federal government estimates of annual flu fatalities.
His institute’s current forecast, which runs to June 1, assumes there will be an additional 62,000 U.S. deaths and 690,000 global deaths from COVID-19 by that point. 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 more cautious government statements about when the pandemic will end. Britain last week said it expects a slow emergence from one of the world’s strictest lockdowns, despite having one of the fastest vaccination drives.
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 “Green Pass” immunity documents to people who have recovered from COVID-19 or been vaccinated, allowing them back into hotels or theaters. The documents are only valid for six months because it’s not clear how long immunity will last.
“What does it mean to be past the emergency phase of this pandemic?,” said Stefan Baral, an epidemiologist at the Johns Hopkins School of Public Health. While some experts have asked whether countries could completely eradicate any case of COVID19 through vaccines and stringent lockdowns, Baral sees the goals as more modest, but still meaningful. “In my mind, it’s that hospitals aren’t full, the ICUS aren’t full, and people aren’t tragically passing,” he said.
“All you need is one little flick of a variant (sparking) another surge, and there goes your prediction.” Dr. Anthony Fauci
WORSE THAN FLU