President Obama sought to assure the nation on Saturday that his administration is taking ever step available to combat the recent outbreak of the H1N1 virus.

In his weekly radio and internet address, Obama carefully discussed the steps his administration to combat the virus, of which there are now 615 cases in 15 counties, according to the World Health Organization.

"It is my greatest hope and prayer that all of these precautions and preparations prove unnecessary," Obama said. "But because we have it within our power to limit the potential damage of this virus, we have a solemn and urgent responsibility to take the necessary steps."

Obama noted that this virus is different than previous outbreaks, such as the bird flu of a few years ago, because it is transferred from human to human. The president also said he is unsure why the virus has been less potent in the U.S. than in Mexico, where there have been significantly more fatalities.

The president said the government is "investing every resource necessary to treat this virus and prevent a wider outbreak."

"The good news," he said, "is that the current strain of H1N1 can be defeated by a course of antiviral treatment that we already have on hand."

Additionally, Obama said the government has delivered more than 10 million courses of treatment for the disease to the states from the Strategic National Stockpile. His administration has also urged people to stay home from school or work if they feel sick, he added, and launched MySpace, Facebook and Twitter pages so people can monitor the situation on a real time basis.

"Out of an abundance of caution," Obama said. "I have also asked Congress for $1.5 billion if it is needed to purchase additional antivirals, emergency equipment, and the development of a vaccine that can prevent this virus as we prepare for the next flu season in the fall."