The ALS Ice Bucket Challenge has gone viral to an extent rarely achieved by health-care topics.

The challenge format is simple – somebody has water, often full of ice cubes, dumped over their head. They then nominate people they know to undertake the same challenge.

There have been in excess of 2.4 million ice bucket-related videos posted on Facebook, and 28 million people have uploaded, commented on or liked ice bucket-related posts.

On image sharing website Instagram there have been 3.7 million videos uploaded with the hashtags #ALSicebucketchallenge and #icebucketchallenge. Justin Bieber’s has been the most popular – with about one million “Likes”.

The stunt is typically intended to raise money and awareness for the Amyotrophic Lateral Sclerosis (ALS) Association.

Justin Bieber’s Ice Bucket Challenge has been the most popular on Facebook with about one million Likes (photo Justin Bieber)

From July 29 to August 28 this year ALS received $98.2 million – compared with $2.7 million donated during the same period last year.

Google searches for both ALS and Lou Gehrig’s Disease, an alternative name in the US, rose sharply from August 13 to a peak on August 21. Since then they have been declining.

From August 1 to August 27 this year, the ALS Wikipedia page had 2,717,754 views. This compared with the 1,662,842 people who had visited the page during the whole of the preceding 12 months, according to data company Dataviz.

Average daily visits to the ALS association website were about 17,500 before the ice bucket challenge, compared with the peak of 4.5 million visits on 20 August (of which 83% were new to the site). During the past month there have been about 30 million visitors in total.

As of August 29 the Ice Bucket Challenge had 4,483,726 Twitter mentions. ALS Twitter followers had increased from 8,975 in early July to 21,100.

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