The World Health Organisation is expected to announce today that swine flu has become a global pandemic, after calling an emergency meeting to discuss the threat posed by the virus.
The announcement of the first global flu pandemic in 40 years would trigger the fast-track production of vaccines to treat the virus that originated in Mexico in April and has since reached 74 countries, infected more than 27,700 people and caused more than 140 deaths. Most cases have been mild, although employers are being warned to prepare for absences through illness.
A total of 797 cases have been confirmed across the UK, with 311 in Scotland.
Nicola Sturgeon, the Scottish health secretary, said tactics for tackling the disease had changed after it emerged that the virus was spreading uncontrolled in the community.
She told the Scottish parliament this morning that hospitalisation rates were similar to the US, and indicated that attempts to contain the virus had failed and the strategy would be to limit its spread.
Doctors in the worst affected areas – Glasgow, Dunoon and Paisley – will now be allowed to make a swine flu diagnosis in their surgeries rather than wait for specialist or laboratory tests. Only the closest contacts of patients will be given the antiviral drug Tamiflu.
"We have seen a rapid increase in the number of confirmed cases in Scotland over the past 10 days," Sturgeon said.
"Based on this experience, Health Protection Scotland has expressed the view that sustained community transmission appears to be taking place."
By yesterday 18 people had been admitted to hospital, with five in intensive care or high dependency units. Fifteen schools and nurseries are entirely or partly closed.
Sturgeon said it was likely that the WHO would raise the pandemic alert level from five to the highest level of six, but added that this was "not a statement about the severity of the virus … it is simply a statement about the extent of the spread of the virus".
The UK's preparations are believed to be well advanced, but government contingency plans and information for the public have assumed the illness would be far more dangerous than has so far proved to be the case.
Britain's chief medical officer, Sir Liam Donaldson, said health officials were expecting to see larger numbers of cases this autumn and winter with the return of the traditional flu season and the virus may yet change and become more severe.
But there were "very strong" plans in place to deal with the flu and so far the government's approach, including closing schools where necessary, appeared to have worked very wellMargaret Chan, the head of WHO, examined eight countries with large swine flu outbreaks yesterday to see if a pandemic, or global epidemic, should be declared.
Chan said she believed that a pandemic was under way, but wanted clear proof that swine flu was spreading rapidly from person to person outside the Americas before declaring a global epidemic.
This would be the first flu pandemic in 41 years: the last was the Hong Kong flu of 1968.
If a global outbreak is announced, countries would be likely to activate their own strategies. These could mean devoting more money to health services or imposing measures such as quarantines, school closures, travel bans and trade restrictions, some of which WHO opposes.