Beijing Olympic Committee lowers threshold for producing negative COVID-19 test

The Beijing Olympic Committee and Chinese authorities are lowering the threshold for producing a negative test for any participant arriving at the Games, dropping the cycle threshold (Ct) value from 40 to 35.

A communication by Beijing 2022 was sent out Sunday explaining the change. The lower value makes it easier for participants to produce a negative test, especially if previously infected.

This comes 48 hours after the higher threshold value was questioned.

The higher the Ct value, the less infectious a person with COVID-19 is. Many places in Canada use a Ct value of 35.

The NBA and NHL use 30, while the NFL has set its threshold at 35.

"In order to adapt to the reality of the current environment and further support of Games participants, Beijing 2022 and the Chinese authorities, in consultation with medical experts and IOC, refined the countermeasures with the following changes effective 23 January 2022," it said in the communication.

Effective immediately for both airport testing and screening testing, participants whose PCR results have a Ct value greater than or equal to 35 will be managed in the same way as a close contact for seven days and will not generate any close contacts.

Anyone with a PCR result of less than 35 will be considered positive.

Beijing Olympic organizers have confirmed 72 cases of COVID-19 among 2,586 Games-related personnel entering China from Jan. 4 to Jan. 22, with no cases among 171 athletes and team officials arriving in that period.

On Friday, the chair of the Beijing 2022 medical expert panel, Dr. Brian McCloskey, defended the strict protocols in place for participants attending the Olympics in China as necessary to reduce the risk of spread during the Games.

Dr. McCloskey told CBC Sports there are different ways countries handle their protocols. He said they had been exchanging scientific papers with colleagues in China to better understand the evidence behind how the testing gets done.

"We are using a standard PCR test, which is an international standard the World Health Organization approved. Every laboratory sets its own standards in terms of Ct values, but these are consistent across the world," he said.

This will have a considerable impact on participants who have previously tested positive but have recovered.

Infectious diseases specialist, Dr. Isaac Bogoch, expressed initial concern at how high the Ct value was set, saying anyone who has recently tested positive could still be showing values because of residual virus.