HIV in Children
On this page
Direct answer
Without intervention, 20 to 45 per cent of babies born to HIV-positive mothers acquire the virus — in pregnancy, during delivery or through breastfeeding — and with maternal triple-drug ART, safe delivery and infant prophylaxis the figure falls below two per cent. Because maternal antibody crosses the placenta, serology is unreliable before 18 months: diagnosis rests on HIV DNA PCR, first done at six weeks of age under NACO's early infant diagnosis programme. Every confirmed child starts antiretroviral therapy immediately regardless of CD4 count, receives cotrimoxazole prophylaxis, and is breastfed — exclusive for six months with continuation beyond — because a suppressed maternal viral load makes formula feeding the riskier option in Indian conditions.
What you must remember
- Transmission windows: in utero, intrapartum (the largest share) and breastfeeding; viral load is the strongest determinant, which is why every pregnant woman tests under PPTCT and starts lifelong triple ART on diagnosis.
- Infant prophylaxis: nevirapine (or a zidovudine-based regimen for high-risk infants) from birth for six weeks or longer depending on maternal status and feeding.
- Diagnosis before 18 months: HIV DNA PCR — routinely at six weeks, at birth for high-risk infants, repeated per the NACO algorithm; a positive PCR is confirmed and treatment starts without waiting for serology.
- After 18 months, the three-test antibody algorithm is valid because maternal antibody has cleared — the classic sequencing question.
- Clinical clues in a child: recurrent or serious bacterial infections, oral candidiasis beyond six weeks of age, chronic parotitis, lymphoid interstitial pneumonia, failure to thrive, chronic diarrhoea, developmental delay, and tuberculosis out of proportion to exposure.
- ART: treat every confirmed child, whatever the CD4 count; current WHO and NACO preference is dolutegravir-based therapy (abacavir-lamivudine with dispersible dolutegravine), moving on from the older nevirapine- and efavirenz-based sequences still found in exams.
- Cotrimoxazole prophylaxis against Pneumocystis pneumonia — deadly and typical between three and six months in untreated infants — starts at four to six weeks for all exposed infants and continues until infection is excluded.
- Immunisation modifications: IPV replaces OPV and BCG is withheld in symptomatic infection; measles vaccine advances to six and nine months; pneumococcal, Hib and influenza vaccines are added.
- Feeding under NACO: exclusive breastfeeding for six months with complementary feeding to at least a year while the mother is suppressed; mixed feeding before six months increases transmission, and abrupt weaning on diagnosis is never advised.
The exposed infant from birth to 18 months
A mother on ART with an undetectable viral load delivers at a facility; the baby starts nevirapine prophylaxis, receives IPV rather than OPV, gets routine vaccines and is exclusively breastfed. At six weeks the first HIV DNA PCR is collected as a dried blood spot; a negative result keeps prophylaxis and cotrimoxazole going, with repeat PCR testing at intervals per the algorithm. A positive PCR is confirmed on a second sample, and ART begins the day confirmation arrives — not at six months, not when the child falls ill. Serology finally at 18 months documents the loss of maternal antibody; a negative antibody test with prior negative PCR closes the case and stops cotrimoxazole. Every step carries a fixed examinable number: six weeks for the first PCR, 18 months for valid serology, four to six weeks for cotrimoxazole. The favourite wrong answers remain "start ART when CD4 falls" and "switch to formula to prevent transmission" — both contradicted by current guidance.
Where students slip
Reading an infant's positive antibody test as infection: before 18 months a positive rapid test means exposure, and only PCR proves infection. Second, feeding — recommending replacement feeding to a mother on effective ART misreads the guidance, which endorses breastfeeding because contaminated water and diarrhoeal disease outweigh the residual transmission risk. Third, forgetting Pneumocystis: an untreated infant with hypoxic, afebrile pneumonia between three and six months is that disease until excluded. Fourth, the immunisation nuances — live vaccines withheld in symptomatic disease, early measles doses — are memorised poorly and asked often.
Frequently asked questions
When is the first HIV DNA PCR done in an exposed infant?
At six weeks under early infant diagnosis, with birth PCR for high-risk infants; a positive result is confirmed on a second sample before labelling the child infected.
Why is serology unreliable before 18 months?
Passively transferred maternal IgG yields a positive antibody test in an uninfected infant; only virological tests detect true infection in the first year and a half of life.
What feeding is recommended for HIV-exposed Indian infants?
Exclusive breastfeeding for six months, continued to at least a year while the mother takes effective ART; mixed feeding before six months raises risk, and abrupt weaning is never advised.
When does cotrimoxazole prophylaxis start?
At four to six weeks for all HIV-exposed infants, continued until infection is excluded — and lifelong for infected children — guarding chiefly against Pneumocystis pneumonia.
What is the current first-line ART preference for children?
A dolutegravir-based regimen — abacavir plus lamivudine with dispersible dolutegravine — started immediately on confirmation regardless of CD4 count.