SOME NEW BLOOD DONORS UPSET SCREENING OF FIRST-TIMERS REVEALS INFECTIOUS DISEASES.

Byline: Staff and Wire Services

After three days of watching endless loops of the World Trade Center towers collapsing on television, Kristina Lakey of Davison, Mich., decided she could not stand by any longer. She had to do something. So on Sept. 14, she recruited her sister, and they went to their church and donated blood.

A month later, however, Lakey, a first-time donor, got an unpleasant surprise: a letter from the Red Cross informing her that her blood had not been accepted because it tested positive for hepatitis C. She said she had no idea how she might have contracted the virus.

``I was shocked, and I was crushed,'' said Lakey, 19. ``I was trying to do something good. This just seems unfair.''

Since Sept. 11, many more blood donors than usual have been given the unsettling news that they are carrying an infectious disease. ``We've had to send many more letters,'' said Dr. Rebecca Haley, a senior medical officer for the American Red Cross in Washington.

Like Lakey, many donated blood for the first time after the Sept. 11 attacks, and this was the first time their blood was screened for blood-carried diseases, including hepatitis B and C, HIV and syphilis. As a rule, analysts say, 80 percent of donors are people who have previously donated and been screened for diseases. But in the weeks after Sept. 11, the proportion of first-time donors ballooned to 50 percent from the usual 20 percent.

The American Red Cross, releasing its post-Sept. 11 figures Tuesday, noted that the number of first-time donors quadrupled in the three weeks after Sept. 11 from the previous three weeks. About 1,000 donors tested positive for hepatitis C in the three weeks after Sept. 11, compared with 247 in the previous three weeks. The numbers for HIV, hepatitis B and syphilis were also higher.

The number of first-time blood donors in the Southern California region, which includes Los Angeles, Orange County and San Diego, nearly doubled after Sept. 11, according to local Red Cross officials.

And, if averages hold, so did the number of people found to be positive for HIV, hepatitis or one of the other blood-borne diseases that the organization screens for.

``Chances are, when you have large group of first-time donors, you do have spikes'' in the number of people testing positive for diseases, said Julie Juliusson, spokeswoman for the Southern California region of the American Red Cross.

There are 7,700 new donors in an average month in the region. But from Sept. 1 through Nov. 30, there were 41,869 first-time donors, an increase of 81 percent and an average of nearly 14,000 per month, Juliusson said.