'Pandemic vs endemic' sets up two conflicting Covid-19 endgames

The confused messaging cuts to the heart of a debate that was bubbling even before the Omicron variant: at what point does the world move on from the pandemic? PHOTO: NYTIMES

LONDON (FINANCIAL TIMES ) - After the World Health Organisation's (WHO) regional chief for Europe expressed hope last weekend that the continent could be moving to a "pandemic endgame", his WHO superiors moved quickly to play down such optimism.

Director-general Tedros Adhanom Ghebreyesus clarified Dr Hans Kluge's remarks the following day by insisting it was "dangerous to assume... we're in the endgame" of coronavirus while WHO Europe stressed that the "pandemic is not over yet".

The confused messaging cuts to the heart of a debate that was bubbling even before the Omicron variant sparked a global infection surge: at what point does the world move on from the pandemic?

The different positions can be crystallised as "pandemic versus endemic". On the one hand is the scientific community which views the continued threat from variants and patchy global vaccination coverage as evidence that the pathogen has not been overcome.

On the other are those, often politicians, who are keen for the virus that has hung like a millstone around the world's neck for two years to be treated like any other problematic illness - a threat, but one that can be managed.

Mr Pedro Sanchez, Spain's Prime Minister, made that case this month when he said "we are heading towards an endemic illness rather than the pandemic it has been up to now". Yet few health experts think the path to endemicity will be simple.

Prof Tim Colbourn, a global health epidemiology expert at University College London, said "many politicians don't know what endemic means" even if "there's a case for saying the worst is over".

"It doesn't mean severity will get lower," he said. "Endemic usually implies a steady state of equilibrium without large peaks, so we're not really there yet. You could argue the politicians saying so are engaging in wishful thinking."

Prof Marc Van Ranst, a virology professor at University of Leuven, accepted endemic was a broad, ill-defined and often misunderstood term, but it was also too early to say the world had reached such a place.

"As long as Omicron is still present in such numbers, causing massive illness however relatively mild and as long as this overburdens the healthcare sector... we can and should not call this an 'endemic situation'. Not yet," he said.

Despite this, countries including Denmark and England have moved to lift Covid-19 restrictions in an effort to return to normal, as hospital pressures remained low.

Denmark dropped restrictions in spite of soaring infection rates, driven by the Omicron subtype BA. 2, which health authorities estimate could be 50 per cent more contagious than the original Omicron. The end to measures in England this week coincided with a halt in the sharp fall in case rates this year.

Even Thailand, which pursued a zero-Covid policy until last summer, took a tentative step on Friday towards treating the virus as endemic, as health officials outlined guidelines for how to begin treating it like the influenza virus within six months to a year.

Prof David Heymann, a London School of Hygiene and Tropical Medicine professor, said England, where population immunity from vaccines and previous infections was above 95 per cent, had effectively been treating the virus as endemic since the summer.

"They've transferred the risk assessment from the government to individuals, they've provided rapid diagnostic tests which we can use or we can wear masks," he said.

Experts also make the point that just because a disease is endemic does not mean it is not deadly - tuberculosis, malaria and HIV/Aids are all endemic and have killed millions. At the other end of the scale, everyday diseases such as flu are also classed as endemic.

"Endemic diseases... are just a disease that's taken up residence in human populations and continues to transmit until measures are made to stop it from transmitting," said Prof Heymann. "Tuberculosis is endemic, HIV is endemic - all of these infections that have come from the animal kingdom have become endemic."

Omicron does appear less virulent, but its greatly increased transmissibility compared with previous variants poses a challenge in the sheer number of hospital admissions it can cause, especially among the unvaccinated.

The mere fact it was spreading so quickly could also hasten the emergence of new troublesome variants, the WHO and others have warned.

The WHO, which began using the term pandemic in March 2020, is considering how to move from an "acute pandemic response towards long-term, sustained Covid-19 disease control". But as the health body's remit is global, any guidance would have to take into account the situation around the world, rather than in just some countries.

Prof Francois Balloux, director of UCL Genetics Institute, said the root of the problem was an understandable desire of people to get back to living - and as such it was not a surprise that many elected officials were keen to deliver the good news their voters craved.

"There's been a pattern of overpromising... we've all been guilty of it because we want to believe in things," he said, such as that "vaccines would in the relative long term prevent transmission, which intellectually we knew would not happen in a certain way".

Prof Nelson Lee, public health professor at the University of Toronto, predicted Covid-19 would not become "a disease that's constantly occurring in a community" and instead would surge once or twice a year, similar to the way the flu virus behaved.

"It will be like an epidemic. It will come and go depending on the evolution of the virus versus the combined immunity of the population," he said.

However coronavirus plays out, scientists agreed the endgame would arrive eventually.

"It's pretty important to give an idea there's light at the end of the tunnel and that pandemics don't last for ever," Prof Balloux said.

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