Leaflets giving information about swine flu and advice on how to prevent its spread are to start being delivered to all households in the UK later.
The nationwide campaign begins after the number of confirmed cases of the H1N1 virus in the UK has risen to 27.
Five schools have been closed, three in London, one in Devon and one in south Gloucestershire, after pupils fell ill.
Meanwhile in Mexico officials are set to relax flu restrictions after seeing a fall in the number of new cases.
From Tuesday, all homes in the UK are set to receive a leaflet stressing the importance of good hygiene in preventing the spread of swine flu.
The leaflet campaign is the first of its kind since the 1980s
The leaflets also advise people to set up networks of neighbours, friends or relatives who would pick up medicine and other supplies in the event of someone having to stay at home due to flu.
England's chief medical officer Sir Liam Donaldson told BBC Radio 4's Today programme that the last time a leaflet had been sent to every home in the UK was after the outbreak of the Aids virus in the 1980s.
"It reinforces the basic hygiene principles that can play a very important part in halting the spread and reducing the risk to individuals," Sir Liam added.
On Monday, nine further cases of swine flu were confirmed in the UK.
Five of those diagnosed were year seven pupils at Alleyn's School in Dulwich, London, which announced it would close by for at least seven days. All 1,200 pupils plus staff are receiving Tamiflu antiviral drugs.
Governors at another school, Dolphin School in Battersea, London, decided to shut its doors as a precaution after it emerged that two pupils - siblings of pupils at Alleyn's - had been confirmed with the virus.
Swine flu has already closed three other schools - South Hampstead High School in north west London, Downend in South Gloucestershire and Paignton Community and Sports College in Devon.
The two other new cases of the virus confirmed on Monday were adults who had visited Mexico.
They bring the overall totals to 23 in England and four in Scotland. The tally in London has reached 13, according to NHS London.
About 300 other people in the UK are currently awaiting the results of tests to determine whether they have the virus.
And in Hong Kong, several Britons remain under quarantine in a hotel after a guest there became China's first confirmed case of swine flu.
Meanwhile in Mexico, restaurants and cafes in Mexico City are to reopen on Wednesday, with libraries, museums and churches to follow suit a day later.
Environment Secretary Hilary Benn said on Monday that the outbreak in the UK was less severe than first thought, but Health Secretary Alan Johnson told the BBC he expected a second, more serious, wave of cases later this year.
Scottish Health Secretary Nicola Sturgeon told a press conference that no health minister could ignore World Health Organisation warnings about the possible impact of a flu pandemic.
"It's absolutely right that we prepare for the worst here, that's what we've been doing - not that we're necessarily expecting the worst, but we are preparing for that because it's the right and responsible thing to do," she said.
Cases of the virus have been confirmed in Newcastle, Oxfordshire, Devon, Merseyside, Worcestershire, Gloucestershire, as well as London and Central Scotland.
A six-year-old girl in Oxfordshire diagnosed with the flu has made a full recovery, doctors have told the BBC.
Members of the public can call 0800 1513513 for recorded information about swine flu. The number for NHS 24 in Scotland is 08454 24 24 24.
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