Scientists are making a vaccine to protect against the H1N1 virus
Peers have criticised the government's handling of swine flu saying some of its pandemic plans were under-prepared.
The Lords' science and technology committee calls for clarity on how intensive and critical care departments will cope with high patient numbers.
And it wants to know how the government will ensure NHS staff are supported in providing services outside their usual expertise when it's all hands on deck.
Ministers maintain that the UK was well placed to cope with the pandemic.
We will give it careful consideration and it will help inform our response to this pandemic
Health Secretary Andy Burnham, talking about the report
The committee praised the government's actions in stockpiling antiviral drugs such as Tamiflu and entering into advance purchase agreements for pandemic specific vaccines, but it asked for better guidance on ethical decisions on who could have access to these treatments.
Lord Sutherland: "The government are now responding significantly"
Committee chairman Lord Sutherland said: "While the Government have got some things right in preparing for a flu pandemic, such as the stockpiling of antivirals, there are other areas where we appear to be under-prepared."
The committee was disappointed tests to examine how the full range of health services could react in a pandemic were not carried our earlier.
It said the national swine flu helpline in England should also have been set up sooner and asked for assurances that it will cope with high demand this autumn.
Lord Sutherland said the service had been set up with "a hop, skip and a jump" and said: "We are not convinced there was good long-term planning going on."
But ministers said the service could only be launched when levels of infection were "significant".
The telephone and web-based helpline service is designed to relieve pressures on the NHS and GPs.
Over 5,500 people got anti-viral drugs when the flu line opened on Thursday.
But the Lords' committee is asking for assurances that the service will be fully operational by autumn to meet the challenges of the anticipated "second wave" of swine flu.
And it wants to know precisely how the service will interact with NHS Direct.
Ramping up services
The committee also calls for clarity on how intensive and critical care facilities will cope in a pandemic and where there are weaknesses in provision which should be addressed.
"We would, in particular, welcome more detailed information about how it would be possible to 'double' critical care facilities," its report said.
And the committee asked whether NHS staff providing services outside their expertise will be protected from legal action when they provide this treatment.
Lack of clarity on how intensive care facilities will cope with demand
Unclear whether NHS staff working outside their expertise have impunity
Delayed launch of flu helpline and unclear how it fits with NHS Direct
Failure to do early tests of the whole pandemic service
It said there was evidence from the US that in a pandemic some healthcare workers might opt not to volunteer for tasks outside their usual professional competence, partly down to litigation fears.
Health Secretary Andy Burnham welcomed the committee's report, adding: "We will give it careful consideration and it will help inform our response to this pandemic."
He defended the timing of the launch of the national swine flu helpline, saying: "We were always clear that it would only be justified when there were widespread levels of flu-like illness across the country."
Some UK doctors are concerned that the threshold for giving out Tamiflu have been set too low, meaning swine flu could develop resistance to the drug, rendering the treatment useless.
Others, including the Royal College of Surgeons, say NHS working hours law could hamper the UK's ability to tackle swine flu.
RemedyUK, a junior doctors' campaign group, say the requirements of the European Working Time Directive, which say doctors can only work 48 hours a week, should be suspended in light of the pandemic.
A spokesman for the Department of Health said doctors could opt out, adding: "Medical directors will carefully review the local situation as the current pandemic flu outbreak continues."
Liberal Democrat health spokesman Norman Lamb said: "The Government's refusal to find a way round impending EU rules on the 48-hour working week shows how little ministers understand the pressures the NHS are facing.
"It's madness to be depriving hard-pressed services of key staff at such a significant time."
Stephen O'Brien for the Conservatives said they continued to work government on pandemic flu, but added: "The report raises serious questions about ongoing preparedness which the Government must answer in full."
More than 100,000 people in the UK are estimated to have caught swine flu in the past week alone and 31 people have died after contracting the illness.
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