US President Barack Obama has declared swine flu a national emergency.
The White House said the president signed the proclamation concerning the 2009 H1N1 outbreak on Friday evening.
It increases the ability of treatment facilities to handle a surge in H1N1 patients by easing the implementation of emergency plans.
Last week US officials said swine flu activity was widespread in 46 states. More than 1,000 US deaths have been linked to the virus.
Health officials say the infections are already comparable to peak season flu levels.
Vaccine warning
US officials said the president’s declaration was similar to ones issued before hurricanes make landfall.
It allows authorities to bypass certain federal requirements in order to deal more effectively with emergencies.
The aim of the directive is to remove bureaucratic hurdles, allowing sick patients to receive treatment more quickly and giving health-care providers more flexibility in providing it.
Paperwork on patients can be reduced and additional health centres set up outside hospitals to care for the sick.
In his proclamation statement, Mr Obama says the 2009 H1N1 pandemic “continues to evolve”.
“The rates of illness continue to rise rapidly within many communities across the nation, and the potential exists for the pandemic to overburden health care resources in some localities.”
He said the US had already taken “proactive steps” by implementing public health measures and developing an effective swine flu vaccine.
However, the government has admitted there are delays in the delivery of vaccines.
It had hoped to roll out 120 million doses by mid-October.
It now hopes for about 50 million by mid-November and 150 million in December.
Dr Thomas Frieden, of the US Centers for Disease Control and Prevention (CDC), said on Friday: “We are nowhere near where we thought we’d be by now.”
Given the shortfall, New York State on Friday stayed a directive ordering health care staff to be inoculated or risk losing their jobs.
The CDC says widespread influenza activity in 46 states is “unprecedented during seasonal flu”.
It said the hospitalisation rates for laboratory-confirmed swine flu were still climbing.
Although figures are hard to verify, it is thought H1N1 has hospitalised about 20,000 people in the US.
Visits to the doctor for influenza-like illnesses were also much higher than expected for the time of year, the CDC said.
The seasonal flu peak is usually between late November and early March.
Children and young adults have been among the hardest hit by H1N1. Almost 100 of the deaths have been children.
