The ENQUIRER and Star jointly report that Anna Nicole had a raging blood infection. The infection was caused by an un-sterilized needle and contributed to her death.

Tests show Anna Nicole did not have methadone or any other painkilling drug in her system at the time of her death.

The ENQUIRER learned that just before she left the Bahamas for Florida on February 5, three days before she died, Anna Nicole received an injection in her left buttock.

"As she boarded the plane for Miami, Anna Nicole developed a painful abscess at the site of the injection," said a source with knowledge of the case. "The needle wasn't sterile. The pain kept getting worse as the abscess got larger and larger very quickly."

From Miami, Anna Nicole and Howard K. Stern traveled to Hollywood, Fla. The pain from the abscess became excruciating and Anna Nicole developed a high fever.

Anna Nicole, unaware that her blood was being poisoned by infection, had also developed a second infection from a virulent form of norovirus, which causes intestinal problems.

Anna Nicole refused to go to a hospital, a decision that would have saved her life.

On February 6, a Tuesday, Anna spent the whole day in bed. She could not keep fluids down. She was becoming severely dehydrated.

On Wednesday, February 7, Anna seemed somewhat better, but she wasn't, the source said.

"She was still vomiting and suffering diarrhea," said the source. "Again, she spent the whole day in bed, as the abscess continued to grow. She was in such pain, she just wanted to sleep."

Sometime overnight on February 7, Anna ingested the sleeping medication chloral hydrate. The drug is extremely potent. The dose was too much - and in fact it was a toxic level, the ENQUIRER and Star have learned exclusively. On Thursday, February 8, Anna never woke up.

Today at 10AM, Broward County, Fla., Chief Medical Examiner Joshua Perper will hold a press conference to offically announce the former Playboy Playmate's cause of death.