During his 3 1/2 years of life, Matthew Kozup experienced AIDS, mental retardation, pain and months of hospitalization and precautions that often kept him isolated from the people who loved him most -- his mother, father and sister.

Yet Matthew, who weighed but 16 pounds at his death from respiratory failure Thursday night, was remembered yesterday as bringing joy in the midst of desperation to his family in Herndon and his medical attendants in the hospital wards where he fought for life.

The child, who was among at least 47 children nationwide who have developed acquired immune deficiency syndrome from contaminated blood, was buried yesterday at Chestnut Grove Cemetery in Herndon.

In addition to his parents, Susan and Stephen Kozup, he is survived by his 4 1/2-year-old sister, Sarah.

"He offered a lot of love, but he never asked for much in return," said his mother. "If you gave him a McDonald's napkin and let him tear it up, he would give you the biggest smile."

His primary nurse at Fairfax Hospital, Katie Roderick of Franconia, chose not to wear a mask during the child's last admission, when he began to cough repeatedly to breathe. "I didn't want him looking at a mask," said Roderick, a 14-year veteran of pediatric nursing. "I couldn't get my emotions across behind it."

Roderick, who returned to the hospital on her day off when she learned that Matthew was dying, was one of many nurses and doctors who attended his funeral yesterday.

"I really did love that little guy," she said. "It broke our hearts because he was poked so much with all his treatments. We tried to hold him and comfort him. I couldn't help becoming so emotionally involved."

Matthew was born at Georgetown University Hospital in January 1983, two years before a blood test came into use that could detect the presence of the AIDS virus.

Because of complications at birth, he developed cerebral palsy and was given a blood transfusion that later was found to have been infected with AIDS virus.

His family filed a $20 million lawsuit this year in U.S. District Court here against the hospital and the D.C. Chapter of the American Red Cross, which supplied the tainted blood. The case is set for trial next June.

Hospital officials have defended the facility's treatment of the infant, and the Red Cross and the hospital have said all precautions that were commonly followed to screen blood at the time of Matthew's birth were followed.

Matthew's AIDS exposure came to light because of the concerted efforts of his parents to find out why their infant son was so ill.

Stephen Kozup, a computer engineer, diligently read medical journals and learned about the then-experimental test for detecting the AIDS virus that was being performed at the National Institutes of Health in Bethesda.

Kozup asked that doctors at Georgetown perform the test on his son's blood. The result was positive.

Matthew was among the first of at least nine area infants to be infected with AIDS-contaminated blood.

It was months before the local Red Cross, under pressure from the Kozups, the hospital and the federal Centers for Disease Control in Atlanta found out who donated the infected blood.

Georgetown Hospital officials also did not tell the parents of a child who received a transfusion of the same infected blood that sickened Matthew that the blood their child received was contaminated with AIDS. The child died in 1984.

Only in recent weeks has the National Red Cross decided it will locate and notify patients across the country who received blood the Red Cross now knows was contaminated with AIDS virus.

The Kozups described as "bittersweet" the small victories that Matthew's case gained in prompting local hospitals and blood officials to be more forthcoming with parents whose children were accidentally infected.

"He did instill a lot of courage in us," Susan Kozup said of her son. "We were faced with this tragedy and we had no choice but to go on."