One male and one female compete in the discipline, with the woman skiing six kilometres and the man covering 7.5km on a 1.5km loop, with four shooting stages per athlete.

The format allows more opportunities for countries with just one male and female at the top level, and will debut on the World Championship stage in Östersund in Sweden in three years time.

The decision follows the success of mixed relay - consisting of two women and two men - which debuted at the Winter Olympic Games in Sochi in 2014.

Single mixed relays have already been held at World Cup level, as well as at this year's Winter Youth Olympic Games in Lillehammer.

"For years the IBU has worked on the concept of a singled mixed relay," said IBU President Anders Besseberg.

"After having tested out the concept in different IBU events including World Cups, the single mixed relay has been very much welcomed by our athletes, member federations and big crowds of biathlon fans. 

"Therefore we find the time has come to include it in our World Championships programme. 

"IBU is also proud to be the first international winter sport federation to have introduced mixed events on the highest competition level, and we fully understand that others are following our success of developing mixed gender events." 

Patrik Jemteborn, the President of the Organising Committee for Östersund 2019, welcomed the news.

"For us it is like winning the top prize," he said.

"Single mixed relay is a very exciting form of competition that favours the smaller nations who may not have as big a team. 

"Our ambition with the IBU Biathlon World Championships 2019 in Östersund, from the outset has been to create better conditions for the small nations and thus create a larger biathlon world so it fits like a glove. 

"We are now in intensive discussions with the IBU to put an exact competition programme that will be as good as possible for the audience, competitors and the media."