Test, test, test? Scientists question costly mass COVID checks

For many people worldwide, having cotton swabs thrust up their nose or down their throat to test for COVID-19 has become a routine and familiar annoyance.

But two years into the pandemic, health officials in some countries are questioning the merits of repeated, mass testing when it comes to containing infections, particularly considering the billions it costs.

Chief among them is Denmark, which championed one of the world’s most prolific COVID testing regimes early on. Lawmakers are now demanding a close study of whether that policy was effective.

“We’ve tested so much more than other countries that we might have overdone it,” said Jens Lundgren, professor of infectious diseases at Rigshospitalet, University of Copenhagen, and member of the government’s COVID advisory group.

Japan avoided large-scale testing and yet weathered the pandemic relatively well, based on infection and death rates. Other countries, including Britain and Spain, have scaled back testing.

Yet repeated testing of entire cities remains a central part of the “zeroCOVID” plan in China, where leaders have threatened action against critics.

“We need to learn, and no one did it perfectly,” said Dale Fisher, chair of the World Health Organization’s Global Outbreak Alert and Response Network.

The WHO urged countries to “test, test, test” all suspected cases after the coronavirus was first identified. Global surveillance helped scientists understand the risk of severe illness or death, as well as the risk of transmission.

Now, with the dominance of the relatively milder Omicron variant and the availability of vaccines and more effective treatments, governments should consider more strategic policies, such as population sampling, experts said.

Covid pandemic killed 13 to 17 million in 2020-21: WHO Pulling back too drastically, however, could leave the world blind to a still-changing virus, some officials said.

WHO guidelines have never recommended mass screening of asymptomatic individuals - as is currently happening in China - because of the costs involved and the lack of data on its effectiveness.

Denmark ultimately recorded similar case numbers and death rates as other countries with less widespread testing. This has prompted a majority of parties in parliament to call for an investigation into the strategy.

In the last two years, Denmark’s population of 5.8 million logged more than 127 million rapid and PCR tests, all provided free. In total, Denmark spent more than 16 billion crowns ($2.36 billion) on testing, according to the Danish Critical Supply Agency.

Neighbouring Norway, with a similar population size, only performed 11 million PCR tests, while Sweden, home to nearly twice as many people, completed around 18 million, according to Our World in Data.

Christine Stabell Benn, professor of global health at University of Southern Denmark, said Denmark’s strategy was expensive and results “undocumented”.

“The mass testing approach took away the focus from testing where it really matters: among the vulnerable.”

Other experts – and the Danish government - said widespread testing reduced the transmission rate and helped people re-enter society, boosting the economy and their own mental health. The economy took a relatively milder hit than other European countries, according to a government report released in September.