Infants can contract HIV from an HIV-positive mother during pregnancy, at birth or through breastfeeding. HIV, the virus that causes AIDS, manifests differently in babies than in adults, generally developing more quickly and affecting growth and development as well as overall health.
Tests to check for the presence of HIV's RNA (polymerase chain reaction test) are normally run on the children of HIV-positive women. This is because a newborn will have his mother's antibodies to the virus, making standard antibody tests useless.
About one out of five HIV-positive children develop become seriously ill during the first year of life and die mostly before the age of four. In other children, HIV progresses more slowly and they may not develop symptoms for years, according to the National Institute of Allergy and Infectious Diseases.
Infants and toddlers with HIV are slow to grow physically and mentally. They may have trouble gaining weight and height and are behind other children in skills like crawling, walking and speaking, the NIAID says.
Children with HIV may develop HIV encephalopathy, a brain disease. Effects include seizures, trouble walking and performing poorly in school.
Babies with HIV also experience opportunistic infections. The most commonly fatal of these is a fungal pneumonia, pneumocystis (formerly known as PCP). HIV-positive children also develop thrush, an oral fungus, and chronic diarrhea, and become more sick than other children as the result of infection with childhood illnesses.
HIV-positive babies face repeated hospitalizations for infections. Children, like adults, can be treated with antiretroviral drugs to manage HIV.