Four-year-old Carlos, who makes a lengthy trip every two weeks with his teenage aunt to a special clinic in El Salvador's capital, has no notion of the cruel stigma that comes with his HIV diagnosis.

Governments and aid groups across the region are organizing official parades and cultural events Saturday to raise awareness and celebrate World AIDS Day.

But in Central America, HIV and AIDS patients carry a burden that is heavier than the medical consequences of the virus that still has no cure.

Carlos's aunt, just 16 years old herself, washes and irons clothes to support the pair ever since her sister died of AIDS a year ago. Neither her parents nor Carlos's other grandparents give them any financial help.

"I would like to go to school or have a formal job," the teenager said, "but there is nobody else to take care of him and I can't think about abandoning him."

Tears streaming down her face, she explained that the preschool in their village refused to enroll Carlos because of his HIV status. Carlos is a pseudonym as the family preferred he remain anonymous.

More than 3,000 children are infected with HIV in Central America, according to official statistics. Most of them, some 2,180, are in Honduras, but El Salvador is second, with 580 HIV-positive kids.

Carlos, a cheerful and active boy, is luckier than many. His twice-monthly visits to the Center of Excellence for Children with Immunodeficiency in San Salvador net him life-saving antiretroviral drugs as well as other important medical care.

It is the only clinic of its kind in the country, and Carlos and his aunt have to travel 135 kilometers (84 miles) to get there.

With its staff of three doctors and three nurses, it dispenses state-sponsored medical care and drugs to children up to age 18, at no cost. The kids also get psychological counseling, paid for by a private foundation.

The center serves some children from Guatemala and Nicaragua as well.

As Carlos waited for his treatment on a recent visit, he got a checkup from a dentist.

Cartoons of children covered the walls, an attempt to warm up the austere environment of the clinic full of HIV-positive kids.

In another cubicle, a 52-year-old woman held an eight-month-old baby with big black eyes who was entertaining herself with some rubber animals as she waited. Older kids waiting nearby were playing on the center's computers.

Like many HIV-positive kids, this baby was here with her grandmother.

"I bring the girl to the hospital, my daughter cannot. She already developed AIDS, and is only 18 years old," the woman told AFP shakily. "My life has changed with pain since I learned that the two are ill."

She works at various jobs to support everyone.

"Many children come with their grandparents because their parents have died and no other family member will take care of them. It's a travesty," said Sandra Ayala, a social worker at the center.

"Many have suffered contempt or abuse from their own families."

Carlos's young aunt said she sometimes doubts she is up to the challenge of raising her nephew on her own.

But her reward, she said, comes when Carlos gazes at her with his big, innocent eyes and calls her "mama."

"I love him like my son. I'm going to do everything possible to see that he grows and has opportunities," she vowed.

"It hurts to see the discrimination against him. Neither he, or any child, deserves that."