As blood donors come to give a pint, new precautions are being taken to make sure their donations are clean.
"Anytime something new comes up," explains Lorie Schenck of Tyler's Stewart Blood Center, "the FDA makes sure we are on top of it so we can maintain the safety of the blood supply."
Donated blood was already tested for things like HIV and hepatitis. Now the worry involves new diseases, and questions about SARS symptoms and tests for West Nile Virus join the precautions.
"We are going to make sure that the blood is as safe as possible," Schenck says.
Last year, 215 people contracted West Nile in Texas. An estimated twenty of those cases came from tainted blood. Mandatory testing for the virus begins Tuesday.
"If it comes back positive," Schenck says, "you'll be asked to come back in 28 days to be retested just to make sure the virus is no longer in you."
West Nile is especially dangerous, since some people carry the disease without showing the symptoms. Blood supplies are already critical and the Fourth of July weekend is coming up, and Stewart Blood Center says the new tests may cut even further into their supply.