he words “we love the NHS” rose to become the most-written about topic on Twitter as a campaign to defend British hospitals swept the internet.

The Prime Minister, his wife Sarah and Health Secretary Andy Burnham all added messages of support.

“NHS often makes the difference between pain and comfort, despair and hope, life and death. Thanks for always being there,” Mr Brown said on Downing Street’s Twitter page.

Mrs Brown said she loved the health service “more than words can say.”

The US president is trying to introduce changes which would allow more uninsured Americans to get access to healthcare.

But opponents have paid for a $1m (£600,000) advertisement campaign warning it is a “socialist” plan to mimic Britain’s “evil” national health service.

The controversial adverts have so far provoked nearly 4,000 posts of support using the Twitter hashtag #welovetheNHS.

Most have shared personal stories about their own friends and family.

Some of the posts on Twitter

 ”My Dad was given 6 wks to live – without NHS I wouldn’t have had him for 2 more years after acute myloid leukaemia diagnosis,” Twitter user ‘laragreenway’ posted.

“My brother had a heart attack last week and has been given world class care,” ‘mwskinn’ wrote.

It has also won support from NHS Direct, which has its own Twitter account.

The row has been further fuelled by a scathing blog post from former Deputy Prime Minister John Prescott on the Conservative MEP Daniel Hannan.

The EU politician criticised the NHS on US television, saying “I wouldn’t wish it on anybody,” due to “huge waiting lists” and “bad survival rates”.

He has previously told American viewers the health service was a “60-year mistake”.

Mr Prescott said the comments undermined the Conservatives’ claims they are a progressive party.