The Ulster Unionist MLA for North Antrim revealed the news on social media this afternoon (Sunday).
He said on Twitter: “Unfortunately today I have tested positive for Covid-19.
“While self-isolating and following public health guidance, I will continue to carry out my duties as fully as possible.”
Many people have extended their good wishes to Mr Swann on hearing the news.
Among them was Simon Coveney, the Irish Minister for Foreign Affairs and Defence, who said: “Get well soon. Take care of yourself Robin.”
Another well-wisher said: “Robin, I am praying for you and your family. Thank you for what you have done on behalf of our society during these past two years.
“Your example of public service and compassionate conviction in the most trying of circumstances are an inspiration. Godspeed in your Covid recovery.”