Former Olympic swimming champion Cameron Van der Burgh said Sunday that he contracted the novel coronavirus.

“I have been struggling with Covid-19 for 14 days today. By far the worst virus I have ever endured despite being a healthy individual with strong lungs(no smoking/sport), living a healthy lifestyle and being young (least at risk demographic),” he said on Twitter.

Burgh, 31, said that despite the most severe symptoms having eased, he is still battling serious fatigue and a residual cough that he could not shake.

“Please, look after yourself everyone! Health comes first – COVID-19 is no joke!” he

Read more: Olympic gold medalist Van der Burgh battling COVID-19