According to information forwarded by the US Centers for Disease Control and Prevention (CDC), the country's first round of a 'nasal' vaccine to combat the deadly flu virus - called 2009 H1N1 or swine flu - would likely be distributed in the beginning of October.

The flu, which has already acquired an epidemic status worldwide, has killed as many as 600 people in the US since April.

Different health care organizations, physician practices, and schools can register to receive the vaccine, which will first be administered to 'high-risk' groups; and later to healthy adults below 64 years, and people above 65 years, who face the lowest risk.

Going by federal guidelines, the 'high-risk' groups comprise pregnant women; health care workers; people living with or looking after children below 6 months; people aged 6 months through 24 years; and people suffering from chronic health problems or compromised immune systems.

However, Jay Butler, chief of the CDC's H1N1 Vaccine Task Force, cautioned that some high-risk groups might not be able to take the nasal vaccine, which is made with a live form of the virus.

Commenting on the availability of the H1N1 vaccine, Butler said: "Initially, we anticipate about 3.4 million doses of the vaccine will be available. Later, we anticipate seeing at least 20 million new doses of vaccine weekly going into December."