BLOOD DRIVE TO AID THOUSAND OAKS BOY; 3-YEAR-OLD TO UNDERGO MARROW TRANSPLANT FROM 6-MONTH-OLD BABY SISTER.

Byline: Sonia Giordani Daily News Staff Writer

Since doctors diagnosed Steven Koss with aplastic anemia more than a year ago, the 3-year-old Thousand Oaks boy has forged a brave battle for his life.

The toddler's severe blood condition takes his blood cell and platelet counts to dangerously low levels, often leaving him tired and weak.

``He can't play with other kids. He can't go out much,'' said his mother, Shannon, as her son spent much of Friday afternoon playing the Candyland game in his bed. ``His immune system is not that strong, and we don't want to put him at risk.''

For months, Steven depended on regular blood transfusions to boost his blood cell and platelet counts while the whole family waited for news of a potential bone marrow match from any of the nearly 4 million people on the National Marrow Donor Program registry.

But the miracle match came just six months ago, when Steven's sister, Serena, was born and showed a solid match with her brother's marrow. Doctors now hope to transplant Serena's marrow into her big brother in an operation tentatively scheduled for mid-December.

``After the operation, we can't even predict the number of blood transfusions he might need to help him boost his blood cells and fight infections and viruses,'' his mother said.

Hoping to help secure blood for Steven's transfusions and to raise awareness for the national marrow donor program, the American Red Cross is hosting a blood drive today at the Janss Mall in Thousand Oaks from 10 a.m. to 3 p.m. Donors can also be screened to participate in the National Marrow Donor Program.

``The more people we get on the register, the better chance we have for a match,'' said Lynnette Chandler, founder of Children For Tomorrow, dedicated to recruiting and registering marrow donors in Ventura County to help the more than 2,000 people across the country who need transplants.

In Ventura County alone, 119 residents like little Steven suffer from various forms of anemia and other serious illnesses that require bone marrow transplants.

Valerie Sun, a Thousand Oaks High School senior also battling aplastic anemia, has been searching for a blood donor for more than five years.

The 15-year-old girl has helped to coordinate a handful of marrow donor drives in recent months, the latest scheduled for Dec. 7, at the Ventura Street Fair on Main Street in Ventura.

Also next Sunday, a blood and bone marrow drive will be from 10 a.m. to 4 p.m. at St. Jude Catholic Church in Westlake Village, where 44-year-old Joe Haskin is a parishioner.

The Westlake Village resident and father of four has been battling non-Hodgkin's lymphoma for just over a year. After six months of chemotherapy and numerous other medical treatments, doctors told Haskin a marrow transplant could save his life.

``The only other option now is a bone marrow transplant,'' said Julie Feely, a Westlake Village resident and Haskin's friend who helped organize Sunday's drive.

``We hope that by some miracle we will find someone in the area whose marrow matches with Joe. And if that isn't our fortune, then at least we can help get more people on the national marrow registry and help someone else find a match,'' Feely said.