Sensitive Chinese tests catching more Covid cases than bargained for

Athletes fear they could be forced to miss the Winter Olympics in Beijing due to the testing procedures adopted by the host country China.

A woman takes a selfie in front of a display of Bing Dwen Dwen, the mascot of the 2022 Beijing Winter Olympics, at the Olympic Park in Beijing Picture: AFP

Olympic officials are bracing for a rush of positive Covid cases among arrivals into Beijing – with some athletes possibly having to forfeit their life’s dream – as early participants have been caught up in China’s sophisticated coronavirus testing regime.

Every day people connected with the Games – at this stage mainly technicians working for the Olympic Broadcast Service preparing the international television feed as well as technical officials for Games venues – have tested positive upon arrival at Beijing International airport.

Insiders said the numbers being quarantined were higher than had been anticipated at this early stage.

The International Olympic Committee says that infection rate upon arrival in Beijing is 1.53 per cent. About two-to-three people on every full plane load.

With the rush of Games competitors, support staff and media expected in the next fortnight for the February 4 opening, the issue could become all-consuming.

“The danger here is that these Games could be the ‘hotel Olympics’,’’ said one official in reference to the immediate isolation in a hotel room for positive arrivals or when someone tests positive in the daily PCR tests.

The exact numbers of positive cases are unclear. At the Tokyo Summer Olympics, 33 people associated with the Games tested positive, but that was before the advent of the more infectious Omicron variant.

China’s officials said more accurate tests were being used to detect Covid-19 than what has been used in the West.

But the sophistication of the Chinese tests, which use a PCR cycle threshold (CT) value of up to 40, is feared to be picking up dead remnants of the virus in people previously exposed. The Australian knows of two people previously infected with Covid who had returned a slate of negative PCR tests only to have tested positive at Beijing airport.

A health worker takes a swab for the Covid-19 in Beijing Picture: AFP

Athletes, particularly those who haven’t had a recent infection, are highly anxious about contracting a last-minute infection. But those who have been infected in the past month have been told by some national Olympic committees that they, too, run a heightened risk of testing positive.”

Many athletes are having daily testing to ensure they have a detailed medical history prepared to argue their case if they are caught up in the testing drama.

PyeongChang silver medallist Matt Graham, who has been recovering from shoulder surgery, said his only movements had been between his bedroom and his physiotherapist.

He has since flown to Finland for an isolated training camp with his mogul teammates.

“To get into a normal Olympics is pretty tricky and then to get into these ones is even harder with all the hurdles – to have all the Covid jabs and you can’t return positive tests,” Graham said.

“We are just sticking to ourselves, not mingling with the general population nor hanging out with anyone.”

IOC director Pierre Ducrey told a technical briefing last week that China was using PCR tests with a CT of 40 cycles which was “like many other labs in the world”.

But many other labs use a much lower CT score.

The University of Oxford said a positive result was given if a fluorescent signal developed after the amplification of the sample. The CT is the number of amplification cycles required for the fluorescent signal to become strong enough to confirm a positive ­result.

Because of the way a PCR test works, the more virus in a sample to start with the fewer cycles are needed for a signal to be detected and the lower the CT value.

While a low CT value is associated with a high viral load, high CT amplifications pick up minute amounts of virus that are unlikely to be infectious.

Australian moguls skier Matt Graham, pictured practising in Brisbane last week, has opted for an isolated camp in Finland in preparation for the Beijing Games to protect himself from the virus Picture: Getty Images

Medical experts said high CT results are also seen in the earliest stage of infection, in the lingering post-Covid phase or where the sample was degraded.

Athletes who have had the virus in the past 30 days have to submit two extra negative PCR tests to the Chinese authorities for assessment more than a week before they are due to fly and receive a medical clearance. This is on top of the two negative PCR tests required before boarding the flight.

Some Australian athletes have had recent Omicron infections as they compete in world cup competitions to qualify for the Games including slopestyle athlete Tess Coady, who won a world cup ev­ent in Switzerland last weekend.

She said: “The people who are stressing the most about it are the ones who haven’t had it yet because of the belief that there is a certain level of immunity – who knows how much – if you have already had it. It would be pretty earth shattering to have your dreams crushed by a cold.’’

Coady said other athletes had missed qualifying events because of coronavirus.

“Covid adds such a complication to the whole process and some people have been screwed pretty hard by it,’’ she said.

Even with this extra testing, some athletes and officials previously infected still face a higher risk of spending time in isolation if the PCR test picked up remnants of the virus upon arrival in Beijing.

Officials said they would prioritise analysis of athlete samples and those of people who work in critical areas if these particular situations arose.

IOC Games Operation director Pierre Ducrey said: “We have worked with the organisers to try and minimise the time in which athletes can recover from Covid before they depart (for China). If they are recovering early enough before departing we give them the chance to be able to compete.”

Australian slopestyle snowboarder Tess Coady has recently recovered from Covid Picture: Getty Images

He said the onus to be virus-free was on the athletes.

“The real key here is about education, prevention in the events, in the training camps, in the everyday life of the athlete. As for all Olympic participants they need to be extremely careful not to be in that situation because if they were to test positive for a duration of time, which overlaps with the duration of the Games, it would not be possible for them to participate.”

Olympic organisers have also tried to have the three-week isolation period in China shortened for any positive Covid cases. If symptomatic, the positive cases are isolated in a local hospital.

Ducrey said that if Olympic athletes had three consecutive days without symptoms and two consecutive days with a negative test they would be released.

For anyone still testing positive after 14 days in isolation, the IOC said it would refer the case to a medical panel for analysis.