A woman sacked as communications director of the New York-based internet empire InterActive Corp for having made a puerile tweet that linked Aids with race, has issued an apology to the “millions of people living with the virus”.

Justine Sacco, the dismissed head of corporate communications for Barry Diller's company, issued a contrite statement on Sunday to the Star newspaper in South Africa where she has travelled to be with her family over the holiday season. It was during the 11-hour flight from London to Cape Town that she became the latest example of the power of Twitter to destroy those who cause offense through unthinking use of the social media site.

Shortly before she boarded the flight on Friday she tweeted:

Going to Africa. Hope I don't get AIDS. Just kidding. I'm white!

In her statement, the PR executive said that she was in “anguish knowing that my remarks have caused pain to so many people” in South Africa where she was born and where her father still lives. "Words cannot express how sorry I am, and how necessary it is for me to apologize to the people of South Africa, who I have offended due to a needless and careless tweet.”

She added: “There is an AIDS crisis taking place in this country, that we read about in America, but do not live with or face on a continuous basis. Unfortunately, it is terribly easy to be cavalier about an epidemic that one has never witnessed firsthand.”

Sacco turned into a notorious Twitter superstar while she was in the air. During her long flight to South Africa, unbeknownst to her, she became an internet phenomenon – the offending remark was retweeted over 2,000 times.

By the time she disembarked her ignorant comment on Aids had been picked up by Buzzfeed, gone viral on Twitter with the hashtag #HasJustineLandedYet trending, and Sacco was in deep trouble. She deleted her offending tweet and her entire Twitter account soon after landing, but by then it was already too late.

On Saturday IAC, which owns internet ventures such as the Daily Beast, Ask.com, Dictionary.com and Match.com dismissed her for what it called her “hateful statements”. Though the company added that it hoped that “time and action, and the forgiving human spirit, will not result in the wholesale condemnation of an individual who we have otherwise known to be a decent person at core."