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Human Immunodeficiency Virus (HIV) Infection in Children and Adolescents


Geoffrey A. Weinberg

, MD, Golisano Children’s Hospital

Reviewed/Revised Mar 2023 | Modified Aug 2023
Topic Resources

Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and makes people more vulnerable to other infections and some cancers and causes acquired immunodeficiency syndrome (AIDS).

  • Human immunodeficiency virus (HIV) infection is caused by the HIV virus, which can be transmitted through sexual contact, blood transfusion, and, in young children, is typically acquired from the mother at the time of birth.

  • Signs of infection in children include slowed growth, enlargement of lymph nodes in several areas of the body, developmental delay, recurring bacterial infections, and lung inflammation.

  • The diagnosis is based on blood tests for HIV infection.

  • Anti-HIV medications (called antiretroviral therapy or ART) can control the effects of HIV infection and allow children to live without complications.

  • Children are treated with the same medications as adults.

  • Pregnant women with HIV infection can prevent transmitting the infection to their newborn by taking antiretroviral medications, feeding their newborn formula rather than breast milk, and, for some women, undergoing a cesarean delivery.

There are two human immunodeficiency viruses:

  • HIV-1

  • HIV-2

Infection with HIV-1 is by far more common than infection with HIV-2 in almost all geographic areas. Both progressively destroy certain types of white blood cells called lymphocytes Lymphocytes One of the body's lines of defense ( immune system) involves white blood cells (leukocytes) that travel through the bloodstream and into tissues, searching for and attacking microorganisms and... read more Lymphocytes , which are an important part of the body's immune defenses. When these lymphocytes are destroyed, the body becomes susceptible to attack by many other infectious organisms. Many of the symptoms and complications of HIV infection, including death, are the result of these other infections and not of the HIV infection itself.

HIV infection may lead to various troublesome infections with organisms that do not ordinarily infect healthy people. These are called opportunistic infections because they take advantage of a weakened immune system. Opportunistic infections may result from viruses, parasites, fungi, and sometimes bacteria.

Acquired immunodeficiency syndrome (AIDS) is the most severe form of HIV infection. A child with HIV infection is considered to have AIDS when at least one complicating illness develops or when there is a significant decline in the body's ability to defend itself from infection.

Only about 1% of the people infected with HIV in the United States have been diagnosed as children or young adolescents. HIV infection in children has now become rare, because of greater testing and treatment of pregnant women infected with HIV. Treatment with antiretroviral medications before and during birth can help prevent transmission from mother to child. Although about 9,000 cases of HIV infection were reported in children and young adolescents between 1983 and 2015, in 2019, fewer than 60 new cases were diagnosed in children under 13 years of age.

Although the number of infants and children with HIV infection living in the United States continues to decrease, the number of adolescents and young adults with HIV infection is increasing. The number is increasing because children who were infected as infants are surviving longer and new cases are developing in adolescents and young adults, particularly in young men who have sex with men. In 2019, about 36,000 new cases of HIV infection in the United States were diagnosed. Of these new cases, 20% were among adolescents and young adults 13 to 24 years of age (the majority of whom were 18 years of age or older).

Worldwide, HIV is a much more common problem among children. In 2021, about 1.7 million children under 14 years of age had HIV infection. Each year, about 160,000 more children are infected and about 100,000 children die. Programs created to deliver antiretroviral therapy (ART) to pregnant women and children have reduced the annual number of new childhood infections and childhood deaths by 33 to 50%. However, infected children still do not receive ART nearly as often as adults.

Overview of Human Immunodeficiency Virus (HIV)

Transmission of HIV Infection

Newborns and young children

HIV is most commonly transmitted to children by

  • An infected mother before birth or during birth

  • After birth through breastfeeding

In infants, HIV infection is nearly always acquired from the mother. More than 95% of children infected with HIV in the United States acquired the infection from their mother, either before or around the time of birth (called vertical transmission or mother-to-child transmission). Most of the remaining children and adolescents now living with HIV infection acquired the infection from sexual activity, including, rarely, sexual abuse.

Because of improved safety measures regarding screening of blood and blood products, in recent years almost no infections have resulted from the use of blood and blood products in the United States, Canada, or Western Europe.

Experts are not sure how many women infected with HIV give birth each year in the United States, but the Centers for Disease Control and Prevention (CDC) estimate is about 3,000 to 5,000. Without ART, 25 to 33% of them would transmit the infection to their baby. Transmission often takes place during labor and delivery.

The risk of transmission is highest among mothers who

  • Acquire HIV infection during pregnancy or while breastfeeding

  • Are severely ill due to HIV infection

  • Have more virus in their body

However, transmission has declined significantly in the United States from about 25% in 1991 to less than or equal to 1% in 2019. Mother-to-child transmission has been reduced because of an intensive effort to test and treat infected pregnant women during both pregnancy and delivery.

Did You Know...

  • In the United States, transmission of HIV from an infected mother to her child has declined from about 25% in 1991 to less than or equal to 1% in 2019.

The virus also can be transmitted in breast milk. About 12 to 14% of infants who were not infected at birth acquire HIV infection if they breastfeed from a mother infected with HIV. Most often, transmission occurs in the first few weeks or months of life but may occur later. Transmission by breastfeeding is more likely in mothers who have a high level of virus in their body, including those who acquired the infection during the time period in which they were breastfeeding their infant.


  • Having unprotected sexual contact

  • Sharing infected needles

All adolescents are at increased risk of HIV infection if they have unprotected sex. Adolescents who share infected needles while injecting drugs are also at increased risk.

In very rare cases, HIV has been transmitted by contact with infected blood on the skin. In almost all such cases, the skin surface was broken by scrapes or open sores. Although saliva may contain the virus, there are no known cases of transmission of infection by coughing, kissing, or biting.

HIV is NOT transmitted through

  • Food

  • Water

  • Touching the same household items (for example, clothing, furniture, and doorknobs)

  • Social contact in a home, workplace, or school

Symptoms of HIV Infection in Children

Children born with HIV infection rarely have symptoms for the first few months even if they have not received antiretroviral therapy (ART). If the children remain untreated, symptoms usually develop at about age 3 years, but some children may not develop symptoms until age 5.

Children with untreated HIV infection

Most children with HIV infection in the United States and in other high-income countries receive antiretroviral therapy. However, if children do not receive treatment, common symptoms of HIV infection include

  • Slowed growth and a delay of maturation

  • Enlargement of lymph nodes in several areas of the body

  • Repeated episodes of bacterial infections

  • Recurring diarrhea

  • Lung infections

  • Enlargement of the spleen or liver

  • Fungal infection of the mouth (thrush)

  • Anemia

  • Heart problems

  • Hepatitis

  • Opportunistic infections

Sometimes children who are not receiving treatment have repeated episodes of bacterial infections, such as a middle ear infection (otitis media), sinusitis, bacteria in the blood (bacteremia), or pneumonia. About one third of children with untreated HIV infection develop lung inflammation (lymphoid interstitial pneumonitis), with cough and difficulty breathing. A variety of other symptoms and complications can appear as the child's immune system deteriorates.

If infants or young children who become infected with HIV infection develop severe illness, called AIDS, they commonly have at least one episode of Pneumocystis jirovecii pneumonia (see Pneumonia in Immunocompromised People Pneumonia in People With a Weakened Immune System Pneumonia is infection of the lungs. Pneumonia in people whose immune system is weakened or impaired (for example, by human immunodeficiency virus [HIV], cancer, organ transplantation, or the... read more ). This serious opportunistic infection can occur as early as 4 to 6 weeks of age but occurs mostly in infants 3 to 6 months of age who acquired HIV infection before or at birth. More than half of untreated children infected with HIV develop the pneumonia at some time. Pneumocystis pneumonia is a major cause of death among children and adults with AIDS.

In a significant number of untreated children with HIV infection, progressive brain damage prevents or delays developmental milestones, such as walking and talking. These children also may have impaired intelligence and a head that is small in relation to their body size. Up to 20% of untreated infected children progressively lose social and language skills and muscle control. They may become partially paralyzed or unsteady on their feet, or their muscles may become somewhat rigid.

Anemia Overview of Anemia Anemia is a condition in which the number of red blood cells is low. Red blood cells contain hemoglobin, a protein that enables them to carry oxygen from the lungs and deliver it to all parts... read more (a low red blood cell count) is common if HIV infection is not treated and causes children to become weak and tire easily. About 20% of untreated children develop heart problems, such as rapid or irregular heartbeat, or heart failure.

Children with HIV infection treated with antiretroviral medications

ART has significantly changed the way HIV infection manifests in children. ART is very effective and allows HIV infection to be managed as a chronic disease. With ART, children with HIV infection usually do not develop any symptoms of HIV infection. Although bacterial pneumonia and other bacterial infections (such as bacteremia and recurring otitis media) occur slightly more often in children with HIV infection, opportunistic infections and growth failure are rare.

Although ART clearly lessens the effects of brain and spinal cord disorders, there seems to be an increased rate of behavioral, developmental, and cognitive problems in treated children infected with HIV. It is unclear whether these problems are caused by HIV infection itself, the medications used to treat HIV, or other biologic, psychologic, and social factors that are common among children with HIV infection.

Because ART has allowed children and adults to survive for many years, more people are developing long-term complications of HIV infection. These complications include obesity, heart disease, diabetes, and kidney disease. These complications appear to be related both to HIV infection itself and to the effects of certain ART medications.

Diagnosis of HIV Infection in Children

  • For pregnant women before birth, prenatal screening and testing during labor and delivery

  • For children after birth, blood tests

  • After diagnosis, frequent monitoring

Pregnant women

The diagnosis of HIV infection in children begins with the identification of HIV infection in pregnant women through routine prenatal screening of blood. Women should be tested for HIV infection early in pregnancy and again in the third trimester to detect newly acquired HIV infection.

Rapid tests for HIV using blood or saliva can be done while women are in labor and delivery units at the hospital. These tests can provide results in minutes to hours.

Newborns and all children under 18 months of age

For all children under 18 months of age, standard adult blood tests for HIV antibodies or antigens are not helpful, because the blood of an infant born to an mother with HIV infection almost always contains HIV antibodies passed through the placenta even if the infant is not infected.

So, to definitively diagnose HIV infection in children under 18 months of age, special blood tests called nucleic acid tests (NATs) are done. The diagnosis of HIV infection is confirmed if the NATs detect genetic material from HIV (DNA or RNA) in the child's blood.

Testing using NATs should be done at frequent intervals, typically in the first 2 weeks of life, at about 1 month of age, and between 4 months and 6 months of age. Such frequent testing identifies most infants infected with HIV by 6 months of age. Some infants who have a very high risk of developing HIV may be tested more frequently.

All children in this age group should be tested if they are born to mothers who

  • Have HIV infection

  • Are at risk of HIV infection

Children over 18 months of age and adolescents


Lymphocytes are a type of white blood cell. The number of CD4+ lymphocytes decreases as HIV infection worsens. If the CD4 count is low, children are more likely to develop serious infections and other complications of HIV, such as certain cancers.

The viral load increases as HIV infection worsens. Viral load helps predict how fast the CD4 count is likely to decrease over the next few years.

The CD4 count and viral load help doctors determine how soon to start antiretroviral medications, what effects treatment is likely to have, and whether other medications may be needed to prevent complicating infections.

Treatment of HIV Infection in Children

  • Antiretroviral medications

  • Ongoing monitoring

  • Encouraging adherence to treatment


All children with HIV infection should be given antiretroviral therapy (ART) as soon as possible, ideally within 1 to 2 weeks of diagnosis. Children are treated with most of the same antiretroviral medications as adults (see Drug Treatment of Human Immunodeficiency Virus (HIV) Infection Antiretroviral Treatment of Human Immunodeficiency Virus (HIV) Infection Antiretroviral medications used to treat human immunodeficiency virus (HIV) infection aim to do the following: Reduce the amount of HIV RNA (viral load) in the blood to an undetectable amount... read more ). However, not all of the medications used for older children, adolescents, and adults are available to young children, in part because some are not available in liquid form.

ART is tailored to the child, but combinations typically consist of the following:

  • Two nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) plus either

  • An integrase inhibitor or a protease inhibitor

Sometimes a non-nucleoside reverse transcriptase inhibitor is given with two NRTIs.

In general, children develop the same types of side effects as adults but usually at a much lower rate. However, the side effects of medications may also limit the treatment.


Increased numbers of virus in the blood may be a sign that the virus is developing resistance to the medications or that the child is not taking the medications. In either case, the doctor may need to change the medications. To monitor a child's progress, the doctor examines the child and does blood tests on the child at 3- to 4-month intervals. Other blood tests and urine tests are done at 6- to 12-month intervals.


Adherence is taking medications as directed. Adhering to prescribed ART dosing schedules is extremely important. If children take ART medications less often than they are supposed to, the HIV in their system can rapidly become permanently resistant to one or more of the medications. Yet, it may be difficult for parents and children to follow and adhere to complicated medication regimens, which can limit the effectiveness of therapy. To simplify regimens and improve adherence, tablets containing three or more medications may be given. These tablets may need to be taken only once or twice a day. The liquid forms of medications are now better-tasting, which improves adherence.

Adherence to ART may be more difficult for adolescents than for younger children. Adolescents also have difficulty adhering to treatment regimens for other chronic diseases such as diabetes and asthma (see also Chronic Health Problems in Children Chronic Health Problems in Children Severe illness, even if temporary, can provoke a great deal of anxiety in children and their families. Chronic health problems may persist for months or forever. They may be severe enough to... read more ). Adolescents want to be like their peers and can feel set apart by their illness. Skipping or stopping treatment may be a way for them to deny having an illness. Additional issues that may complicate treatment and reduce adherence in adolescents include

  • Low self-esteem

  • A chaotic and unstructured lifestyle

  • Fear of being singled out because of illness

  • Sometimes a lack of family support

In addition, adolescents may not be able to understand why medications are necessary when they do not feel ill and they may worry greatly about side effects.

Despite frequent contact with a pediatric health care team, adolescents who have been infected since birth may fear or deny their HIV infection or distrust information provided by the health care team. Instead of directly confronting adolescents who have poor support systems about the need to take their medications, care teams sometimes help the adolescent focus on practical matters such as how to avoid opportunistic infections and how to obtain information about reproductive health services, housing, and succeeding in school (see Transition to Adult Care Transition to Adult Care Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and makes people more vulnerable to other infections and some cancers... read more ).

Preventing opportunistic infections

To prevent Pneumocystis pneumonia Pneumonia in People With a Weakened Immune System Pneumonia is infection of the lungs. Pneumonia in people whose immune system is weakened or impaired (for example, by human immunodeficiency virus [HIV], cancer, organ transplantation, or the... read more , doctors give trimethoprim/sulfamethoxazole to children with HIV infection depending on their age and/or how low their CD4 count Monitoring Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and makes people more vulnerable to other infections and some cancers... read more is. All infants who were born to women infected with HIV are given trimethoprim/sulfamethoxazole beginning at 4 to 6 weeks of age until testing shows they are not infected. Children who cannot tolerate trimethoprim/sulfamethoxazole can be given dapsone, atovaquone, or pentamidine.

Routine childhood vaccinations

Yearly inactivated or live influenza immunization is also recommended for household members.

Some vaccines containing live bacteria, such as bacille Calmette-Guérin (which is used to prevent tuberculosis in some countries outside the United States), or live viruses, such as the oral polio virus (not available in the United States but still used in other parts of the world), varicella, and measles-mumps-rubella, can cause a severe or fatal illness in children with HIV whose immune system is very impaired. However, the live measles-mumps-rubella vaccine Measles, Mumps, and Rubella Vaccine The measles, mumps, and rubella (MMR) vaccine is a combination vaccine that helps protect against these three serious viral infections. The vaccine contains live but weakened measles, mumps... read more , live varicella vaccine Varicella Vaccine The varicella vaccine helps protect against chickenpox (varicella), a very contagious infection caused by the varicella-zoster virus. It causes an itchy rash that looks like small blisters with... read more , and, in some areas of the world, live yellow fever vaccine Prevention Yellow fever is a mosquito-borne viral disease that occurs mainly in the tropics. Yellow fever occurs only in the tropical areas of Central Africa, southern Panama, and South America. Some people... read more and live dengue virus vaccine Dengue vaccine Dengue is a mosquito-borne viral infection that causes fever, generalized body aches, and, if severe, external and internal bleeding (called dengue hemorrhagic fever). About 50 to 100 million... read more are recommended for children with HIV infection whose immune system is not severely impaired.

However, the effectiveness of any vaccination is less in children with HIV infection. Children infected with HIV who have very low CD4+ cell counts are considered susceptible to vaccine-preventable diseases when they are exposed to one (such as measles, tetanus, or varicella) regardless of whether they have received the vaccine for that disease and may be given immune globulin by vein (intravenously). Intravenous immune globulin or immediate vaccination with measles-mumps-rubella vaccine also should be considered for any nonimmunized household member who is exposed to measles.

Social issues

For children in child care or school, or if a child needs foster care, a doctor can help assess the child's risk of exposure to infectious diseases. In general, transmission of infections, such as chickenpox, to children with HIV infection (or to any child with an impaired immune system) is more of a danger than is transmission of HIV from that child to others. However, a young child with HIV infection who has open skin sores or who engages in potentially dangerous behavior, such as biting, should not attend child care.

Children with HIV infection should participate in as many routine childhood activities as their physical condition allows. Interaction with other children enhances social development and self-esteem. Because of the stigma associated with the illness, the routine use of universal precautions in schools and day care centers, and the fact that transmission of the infection to other children is extremely unlikely, there is no need for anyone other than the parents, the doctor, and perhaps the school nurse to be aware of the child's HIV status.

As a child's condition worsens, treatment is best given in the least restrictive environment possible. If home health care and social services are available, the child can spend more time at home rather than in a hospital.

Transition to Adult Care

Once they reach a certain age (typically 18 to 21 years old), adolescents with HIV infection will transition from pediatric care to adult care. The adult health care model is quite different, and adolescents should not just be referred to an adult clinic or office without additional planning.

Pediatric health care tends to be family-centered, and the care team includes a multidisciplinary team of physicians, nurses, social workers, and mental health professionals. Adolescents infected at birth may have been cared for by such a team for their entire life.

In contrast, the typical adult health care model tends to be individual-centered, and the health care practitioners involved may be located in separate offices requiring multiple visits. Health care practitioners at adult care clinics and offices are often managing high patient volumes, and the consequences of lateness or missed appointments (which may be more common among adolescents) are stricter.

Planning transition over several months and having adolescents have discussions or joint visits with the pediatric and adult health care practitioners can lead to a smoother and more successful transition.

Prognosis for HIV Infection in Children

Before antiretroviral therapy (ART), 10 to 15% of children from high-income countries and perhaps 50 to 80% of children from low-income or middle-income countries died before 4 years of age. Today, with ART, most children born with HIV infection live well into adulthood. Increasing numbers of these young adults who were infected at birth have given birth to or fathered their own children.

It is unknown whether HIV infection itself or ART given to children infected with HIV during critical periods of growth and development will cause additional side effects that appear later in life. However, so far, no such side effects have been noted in children infected at or before birth who were treated with ART and who are now young adults.

Because of the way HIV remains hidden within people's cells, medications do not completely eliminate the virus from the body. Even when tests do not detect the virus, some viruses remain within cells. In one instance, a child who was born to an untreated mother infected with HIV was given high doses of ART. Although the ART was unintentionally interrupted when the child was 15 months of age, at 24 months of age, doctors were still not able to detect reproducing (replicating) HIV in the child. However, doctors were able to detect the virus later. Research studies are underway to find out whether giving high doses of ART to suppress the virus, even if only for a short time, leads to better health.

Doctors do recommend that people of any age do not interrupt their ART.

If children with HIV do not receive antiretroviral medications, opportunistic infections occur, particularly Pneumocystis pneumonia, and the prognosis is poor. Pneumocystis pneumonia causes death in 5 to 40% of treated children and in almost 100% of untreated children. The prognosis is also poor for children in whom the virus is detected early (within the first week of life) or who develop symptoms in the first year of life if they do not receive ART.

To date, there is no cure for HIV infection, and it is not yet known if a cure is possible. What is known, however, is that HIV infection is a treatable infection and that long-term survival is possible if effective ART is given.

Prevention of HIV Infection in Children

Preventing transmission from infected mother to child

Current preventive therapy for infected pregnant women is highly effective at minimizing transmission. Pregnant women with HIV infection should begin antiretroviral therapy (ART) by mouth. Ideally, ART should begin as soon as HIV infection is diagnosed and women are ready to follow the therapy as directed. Pregnant women with HIV infection who are already on ART should continue the therapy throughout the pregnancy. Women with HIV infection should also continue ART when trying to get pregnant.

In addition to maternal ART, the antiretroviral medication zidovudine (ZDV) is sometimes given by vein (intravenously) to the mother during labor and delivery. ZDV is then given to the HIV-exposed newborn by mouth twice a day for the first 4 to 6 weeks of life (sometimes along with additional antiviral medications for certain newborns at greater risk of acquiring HIV infection). Treatment of mothers and children in this way reduces the rate of transmission from 25% to 1% or less. Also, cesarean delivery Cesarean Delivery Cesarean delivery is surgical delivery of a baby by incision through a woman’s abdomen and uterus. In the United States, up to 30% of deliveries are cesarean. Doctors use a cesarean delivery... read more Cesarean Delivery (c-section) done before labor begins may reduce the newborn's risk of acquiring HIV infection. Doctors may recommend cesarean delivery for women whose infection is not well controlled by ART. After delivery, ART is continued for all women with HIV infection.

Because HIV can be transmitted during breastfeeding and in breast milk, the decision to breastfeed should be made only after counseling and decision-making discussions with health care practitioners.

In countries where the risks of undernutrition and infection resulting from unclean water or formula are high and safe, affordable infant formula is not available, the benefits of breastfeeding may outweigh the risk of HIV transmission. In these countries, mothers with HIV infection under medical supervision may continue to breastfeed for at least 12 months of the infant's life and then rapidly wean the infant to food. Often their infants are given ART throughout the period of breastfeeding.

Mothers with HIV infection should be advised never to donate their breast milk to milk banks.

Mothers with HIV infection should not prechew (premasticate) food for infants.

Preventing transmission from infected children to others

Because a child's HIV status may not be known, all schools and day care centers should adopt special procedures for handling accidents, such as nosebleeds, and for cleaning and disinfecting surfaces contaminated with blood.

During cleanup, personnel are advised to avoid having their skin come in contact with blood. Latex gloves should be routinely available, and hands should be washed after the gloves are removed.

Contaminated surfaces should be cleaned and disinfected with a freshly prepared bleach solution containing 1 part of household bleach to 10 to 100 parts of water.

These practices are called universal precautions and are followed not only for children with HIV infection but for all children and in all situations involving blood.

Preventing transmission for adolescents

Preventive treatment before exposure

Taking an antiretroviral medication before being exposed to HIV can reduce the risk of HIV infection. Such preventive treatment is called pre-exposure prophylaxis (PrEP).

PrEP is most effective if people take the medication every day, but it can be expensive, so PrEP is recommended most often for people who are not infected with HIV but who have a high risk of becoming infected, such as people who have a sex partner who is infected with HIV, men who have sex with men, and people who are transgender. Older adolescents at risk may also receive PrEP, but issues of confidentiality and cost are more complex than with adult PrEP.

People who use PrEP still need to use other methods to prevent other infections, including consistent use of condoms and not sharing needles to inject drugs.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

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