HIV Infection in Infants and Children

OVERVIEW
The National Institute of Allergy and Infectious Diseases (NIAID) has a lead role in research devoted to children infected with HIV (human immunodeficiency virus), the virus that causes AIDS (acquired immunodeficiency syndrome). NIAID-supported researchers are developing and refining treatments to prolong the survival and improve the quality of life of HIV-infected infants and children through the Pediatric AIDS Clinical Trials Group (PACTG). The PACTG is a nationwide clinical trials network jointly sponsored by NIAID and the National Institute of Child Health and Human Development (NICHD). NIAID also supports research on ways to prevent mother-to-child transmission (MTCT) of HIV through the PACTG and its HIV Prevention Trials Network (HPTN), a global clinical trials network designed to test promising nonvaccine strategies to prevent the spread of HIV/AIDS.

In this era of antiretroviral therapy, epidemiologic studies such as NIAID's Women and Infant's Transmission Study (WITS) are examining risk factors for transmission as well as the course of HIV disease in pregnant women and their babies. Researchers have helped illuminate the mechanisms of HIV transmission, the distinct features of pediatric HIV infection, and how the course of disease and the usefulness of therapies can differ in children and adults.

A GLOBAL PROBLEM
According to UNAIDS (The Joint United Nations Programme on HIV/AIDS) at the end of 2003, an estimated 2.5 million children worldwide under age 15 were living with HIV/AIDS. Approximately 500,000 children under 15 had died from the virus or associated causes in that year alone. As HIV infection rates rise in the general population, new infections are increasingly concentrating in younger age groups.

December 2003 UNAIDS/World Health Organization (WHO) worldwide statistics show

700,000 children under age 15 were newly infected with HIV
Thirteen percent of all new HIV infections were in children under age 15

Three million children in sub-Saharan Africa, the region with the highest number of cases, are living with HIV

More than 95 percent of all HIV-infected people now live in developing countries, which have also suffered 95 percent of all deaths from AIDS. In those countries with the highest prevalence, UNAIDS predicts that, between 2000 and 2020, 68 million people will die prematurely as a result of AIDS. In seven sub-Saharan African countries, mortality due to HIV/AIDS in children under age five has increased by 20 to 40 percent. Life expectancy for a child born in Botswana, the country with the highest HIV prevalence in the world, has dropped below 40 years-a level not seen in that country since before 1950.

The United States has a relatively small percentage of the world's children living with HIV/AIDS. From the beginning of the epidemic through the end of 2002, 9,300 American children under age 13 had been reported to the Centers for Disease Control and Prevention (CDC) as living with HIV/AIDS. The vast majority of HIV-infected children acquire the virus from their mothers before or during birth or through breast feeding. Because of the widespread use of AZT and other highly active antiretroviral therapy (HAART) in HIV-infected pregnant women in the United States, only 92 new cases of pediatric AIDS were reported in 2002. More than three times that number are infected with HIV but have not yet developed AIDS.

The U.S. city with the highest rate of pediatric AIDS through 2002 was New York City, followed by Miami, FL, and Washington, DC.

The disease disproportionately affects children in minority groups, especially African Americans. Out of 9,300 cases in children under 13 reported to the CDC through December 2002, 59 percent were black/non-Hispanic, 23 percent were Hispanic, 17 percent were white/non-Hispanic, and less than 1 percent were in other minority groups.

New anti-HIV drug therapies and promotion of voluntary testing continue to positively effect the death rate. CDC reported a drop of 68 percent from 1998 to 2002 in the estimated number of children who died from AIDS.