Officials said they need more information before making a diagnosis.
Usually, your doctor will order more than one test before making a diagnosis.
The doctor may find something wrong and make a diagnosis right away.
Here's how you can help your doctor make the right diagnosis.
They said a diagnosis was never made on the basis of the test alone.
Treatment should only be given after a positive diagnosis has been made by means of a blood test.
It may be weeks or months before a doctor makes a diagnosis.
You may need many medical tests before a final diagnosis is made.
Eight of the victims died less than 24 months after the diagnosis was made.
A diagnosis can only be made by taking a blood sample.