US Mulls Testing Airline Wastewater As China Covid Surge Expands

The US Centers for Disease Control and Prevention is considering a plan to sample wastewater taken from international aircraft to track emerging Covid-19 variants, Reuters reports.

According to an infectious disease expert, such a policy would provide the best chance of tracking the virus and slowing its entry into the United States, vs. blanket travel restrictions announced this week by the US and other countries, which once again are requiring mandatory negative Covid tests for travelers from China.

“They seem to be essential from a political standpoint. I think each government feels like they will be accused of not doing enough to protect their citizens if they don’t do these,” said Dr. Michael Osterholm, an infectious disease expert at the University of Minnesota, referring to the travel restrictions.

Nearly half of a plane-load of 212 passengers who arrived in Italy’s Milan Airport from China on Monday tested positive for Covid, according to a Wednesday statement by a regional health chief.

This week the United States added its voluntary genomic sequencing program to the Seattle and Los Angeles airports, bringing to the total number of airports that can analyze positive tests to seven.

That may not be enough, according to experts.

A better solution would be testing wastewater from airlines, which would offer a clearer picture of how the virus is mutating, given China’s lack of data transparency, said Dr Eric Topol, a genomics expert and director of the Scripps Research Translational Institute in La Jolla, California.

Getting wastewater off planes from China “would be a very good tactic,” Topol said, adding that it’s important that the United States upgrade its surveillance tactics “because of China being so unwilling to share its genomic data.” –CNBC

China has hit back at critics, calling criticism of its Covid statistics ‘groundless’ – and saying that the risk of new variants is low, as they would likely be more infectious but less severe.

According to CDC spokeswoman Kristen Nordlund, sampling airline wastewater is one of several options the agency is considering.

“Previous Covid-19 wastewater surveillance has shown to be a valuable tool and airplane wastewater surveillance could potentially be an option,” she wrote.

In July, French researchers reported that airplane wastewater tests revealed that negative Covid tests don’t protect against new variants – finding the Omicron strain in wastewater from two commercial airplanes which flew from Ethopia to France in Dec. 2021 despite all passengers having tested negative. 

California researchers reported in July that sampling of community wastewater in San Diego detected the presence of the alpha, delta, epsilon and omicron variants up to 14 days before they started showing up on nasal swabs.

Osterholm and others said mandatory testing before travel to the United States is unlikely to keep new variants out of the country. -CNBC

“Border closures or border testing really makes very little difference. Maybe it slows it down by a few days,” said Osterholm, adding that the virus is likely to spread worldwide anyway, so closing borders would simply delay the inevitable.