Makwala, barred from participating in the final of the 400m by the IAAF last night after he was among those to have contracted the norovirus here, was second in his semi-final in a time of 20.14sec.

He had earlier qualified for the semi-final after finishing in a time of 20.20 in his individual time trial, comfortably inside the 20.53 that he needed to progress.

The 30-year-old All-Africa Games champion looked in good form once again as he ran a superb bend before crossing the line behind American Isiah Young.

But the eyes of the crowd focused solely on Makwala, whose story has sparked both fury and sympathy during these Championships.

The Botswana athlete thanked the IAAF for allowing him to run in the 200m but admitted he was "running with anger" after his widely-condemned omission from the 400m.

"I'm still running with my heart broken," he said. 

"I wish the IAAF had given me the decision to run the 400m first.

"I was ready to run. 

"I don't know who made the decision.

"I'm running with anger - 400m is my race.

"Thanks to IAAF for letting me run today."

Makwala was allowed to compete after he underwent a medical examination today and the IAAF then gave him the green light to participate.

It came after the Botswana Athletics Association wrote to the IAAF requesting he be allowed to take part.

The IAAF recommended Makwala be quarantined for 48 hours after he was hit with the illness, usually brought on by a bacterial or viral stomach bug and which causes diarrhoea and vomiting, on Monday (August 7).

It forced him to miss the first round of the 200m that evening.

Makwala insisted, however, that he had been well enough to race the 400m last night and said he was "heartbroken" by the decision of the IAAF to bar him.

His period in isolation ended at 14:00 today, paving the way for him to be granted permission to race in the 200m.

The IAAF's decision handed Makwala - who said he felt "sabotaged" after his omission from the 400m, a race won by South Africa's Wayde van Niekerk - an unlikely reprieve.

Makwala took full advantage with another confident display as he did not allow the torrential downpours to rain on his parade.

While Makwala was impressive, Van Niekerk looked anything but in his semi-final as he qualified as one of the fastest losers in 20.28.

Makwala's individual time trial, the opening race of the night, was not the first time athletes have had to compete alone on the track.

At last year’s Olympic Games, the American 4x100m women's relay team were allowed to run their heat again after a Brazilian runner impeded Allyson Felix, causing her to drop the baton.

Some of the athletes in the men’s 110m hurdles were also allowed to race in a time trial as a result of torrid rainfall before they took to the start line.

The IAAF cleared Makwala under rule 112 regarding technical delegates.

The ruling states: "The technical delegates control the entries and have the right to reject them for technical reasons or in accordance with the Rule 146.1."

"Rejection for reasons other than technical must result from a ruling of the IAAF or appropriate Area Council or other relevant governing body."

The IAAF caused controversy last night after Makwala was denied entry to the stadium in a last-ditch effort to be able to participate in the final of the 400m.

Video footage emerged of Makwala being denied entry to the dedicated athletes entrance by security.

Makwala was the escorted back to the IAAF office on the Stadium site before he returned to the hotel.

The IAAF were heavily criticised on social media and by the likes of four-time Olympic gold medallist Michael Johnson for the way they dealt with Makwala.

The American said on the BBC that the IAAF had got it "horribly wrong".

The BAA were also critical of the governing body for their supposed lack of communication regarding Makwala and whether he would be able to take to the track for the 400m final.

The IAAF rebutted these accusations by claiming that they had communicated the decision to the BAA and were merely following the regulations laid out by Public Health England (PHE).

Andrew Lichtenthal, the team doctor at the German Athletics Association (DLV), said he fully supported the IAAF's stance on quarantining athletes.

He backed Pamela Venning, the London 2017 head of medical services, who appeared on BBC Television last night to explain the decision taken by the IAAF.

"In short, yes, I agree," he said. 

"What Pam was saying yesterday – it was a fight I must say – she was great. 

"I am on her side. 

"We are very sorry for the athletes. 

"We don’t do this job because we want to take athletes out."

Lichtenthal also claimed the outbreak of the norovirus is still spreading and is not just limited to the Tower Hotel.

The sickness bug has moved to other hotels being used for the event here, including the official IAAF hotel at the Marriott West India Quay, according to Lichtenthal.

"I would hope that if we stay with one to two infections per day, that would be a success," he said.

Canadian team doctor Padraig McCluskey said yesterday that the virus was only circulating around the Guoman Tower Hotel.

The hotel claimed they were "not the source of the illness" following investigations carried out by the IAAF, PHE and environmental health officers.

Members of the Botswana, Germany, Canada, Ireland and Puerto Rico teams - all of which have had athletes who have been hit by the illness - are staying here.

The DLV medical chief cast doubt on suggestions that there were 30 people who had contracted the bug, claiming it was likely to be higher.

"The hotel are still saying 30 but that is 30 official, other hotels have two or three in their hotel," Lichtenthal said.

"But that is only athletes and officials, the volunteers are not in this count."

Lichtenthal also revealed there had been a total of 13 athletes and support staff within the German team who have been affected by the illness.

This includes two unnamed athletes, who have been quarantined at the hotel by the DLV, while 10 are now said to be completely free of the bug.

They have each been given a 50 per cent chance of being able to participate in their respective events.

Around 30 members of the German team have been moved to other hotels in a bid to stop the spread of the virus.

German triple jumper Neele Eckhardt collapsed as a result of contracting the virus but competed in the women's triple jump final on Monday (August 7).

She finished 12th with a best jump of 13.97m.