Shoppers and commuters in Brussels recently were puzzled to find some of the letters missing from the famous Coca-Cola logo in the bustling Place de Brouckère. Coca-Cola Belgium removed the A and O from its logo in support of the Red Cross campaign #MissingType.

The stunt is part of a global initiative to encourage more people to donate blood and fill the missing blood types A, O and B. Businesses and organizations across Belgium, including Coca-Cola, are getting behind the campaign by removing the letters that correspond with these blood types from their names and logos.

The campaign is running in 21 countries, where the Red Cross and local blood banks have teamed up with businesses, governments and the media to raise awareness of the vital need for blood donations.

Every second, three blood transfusions are needed by people in accidents, with blood disorders, following an operation or during childbirth. But over the past 10 years, the number of donors has dropped by a third worldwide. Only three percent of the population donates blood, while 70 percent of people will need a transfusion at least once in their lives.

With this campaign, the Belgian Red Cross aims to attract 38,000 new donors by underlining the vital importance of As, Bs and Os. Coca-Cola is joining 95 businesses and organizations in Belgium calling on people to give blood and save lives.

"The Coca-Cola logo is iconic, but for this important cause we were more than willing to change it," says Ben Bijnens, country director for Belgium and Luxembourg. "We want to do what we can to make people aware of their blood type and help attract new donors. Together with the Red Cross, we want to inspire a global movement of life-savers."

The campaign is gaining massive interest in the media, with articles appearing on leading news websites and in daily newspapers. On social networks, the hashtag #MissingType is being shared en masse.

The campaign is inspired by the success of #MissingType in the UK last year, where 30,000 new blood donors registered in one week.