Some countries monitor the wastewater of flights to China

The US is also considering this measure, according to US media reports.

Paris:

Several countries have said they will monitor wastewater from flights to China in response to a nationwide outbreak of Covid cases.

While this measure will not stop the spread of the virus, it will provide a glimpse into the size of China’s outbreak and whether new variants are emerging there.

– How it works? –

The process includes testing a mixture of urine and faeces from the toilets of flights arriving from China.

The wastewater can then be analyzed to find out about what percentage of passengers have Covid, as well as specific variations.

Local authorities collect wastewater directly after the plane lands and send it to laboratories for testing.

Once the virus has been detected, its genome is sequenced to find out if it is a known subvariant.

Wastewater can also be collected from the entire airport, but this makes it impossible to determine which country the samples originated from.

– What country? –

Belgium, Canada, Austria and Australia are among the countries that have indicated they will test the wastewater of planes arriving from China.

The European Union is expected to follow suit after a majority of national health ministry officials on Tuesday recommended increased monitoring of wastewater.

The US is also considering this measure, according to US media reports.

– Why? –

Infections have skyrocketed in China since last month when the country began lifting strict Covid-free measures, in place since the start of the pandemic.

Several countries including the US said they were asking passengers arriving from China to provide negative Covid test results, angering Beijing.

Unlike such tests, wastewater monitoring will not deter people who are currently positive for Covid.

However, Antoine Flahault, director of the Institute of Global Health at the University of Geneva, said: “These samples provide a window into what is currently happening in China.

He told AFP this could be especially important given “doubts about the transparency and carelessness of official health information coming from the Chinese government”.

The World Health Organization on Wednesday criticized Beijing’s “very narrow” definition of Covid deaths and said China’s official statistics on hospitalizations and deaths in The country is “underrepresented”.

– Less invasive –

Flahault said wastewater monitoring could help fill the gap.

“Knowing that 30 to 50 percent of passengers from China are currently infected is helpful, in the absence of reliable figures,” he said.

It also allows countries to learn about new variants that could change the trajectory of the pandemic, just as Omicron did in late 2021.

Health experts have warned that an explosion of cases among China’s 1.4 billion people could create fertile ground for new strains of the virus.

Sewage monitoring is much easier to do — and much less intrusive — than screening passengers arriving at the airport.

The European branch of the Airports Council International’s lobbying group, which has criticized the screening of passengers arriving from China, has instead called for increased wastewater monitoring.

– Limit –

However, while the wastewater test “works very well”, it does not give a “comprehensive view” of infectious diseases or variants on board, French virologist Vincent Marechal told AFP.

One limitation is that wastewater can only monitor passengers who have used the restroom during the flight.

It also takes days to collect, examine, organize and analyze the findings, which cannot be broken down by individual passengers.

This provides several avenues to quickly act on the results.

“Once you have the information, what can you do with it? Call back everyone on the plane?” Marechal asked.

“It’s exciting, but it’s too late for measures that one can take.”

(Except for the title, this story has not been edited by NDTV staff and is published from an aggregated feed.)