The Pentagon announced on Wednesday plans to expand the number of US troops that will receive anthrax and smallpox vaccinations.

The military will begin giving anthrax and smallpox vaccines to tens of thousands of troops in the Pacific region and Middle East to help protect them against biological warfare, defense officials said.

Specifically, the troops involved are those deployed in South Korea and throughout the Central Command's area of operation.

The expanded vaccination program is the result of an increased supply of the vaccines, and not new intelligence on the threat of anthrax or smallpox weapons in those regions, William Winkenwerder, assistant secretary of defense for health affairs, said a news conference.

Anthrax and smallpox remained to be two of the top biological warfare threats to US forces, and vaccinations remained a safe and reliable way to protect the soldiers, Pentagon spokesman Bryan Whitman said.

In a memo released on Wednesday, Deputy Defense Secretary Paul Wolfowitz called the vaccination programs to protect US troops against exposure to smallpox and anthrax agents "a success."

"Building on that success and the continued threat of biological attack, it is prudent to expand our immunization programs now," Wolfowitz said in the memo.

Since 1998, 1.1 million military personnel have been vaccinated against anthrax.

The anthrax vaccine has been controversial because some military personnel believe it causes health problems. Hundreds refused to take it and were punished or discharged from the military.

Source: Xinhua