Effect of immediate neonatal zidovudine on prevention of vertical transmission of human immunodeficiency virus type 1.
OBJECTIVE
To describe the effects of various short zidovudine (ZDV) prophylactic regimens on vertical transmission of human immunodeficiency virus type 1 (HIV-I) infection, especially the effect of immediate neonatal ZDV prophylaxis.


METHODS
The study included children of HIV-1-infected mothers who were born at a teaching hospital in Bangkok. The ZDV prophylaxis regimens varied by time periods that included: (1) no ZDV (1991-1996); (2) antenatal oral ZDV, 250 mg given twice a day starting at 34 to 36 weeks gestation and continued until labor (1995-1998); (3) antenatal oral ZDV plus immediate neonatal oral ZDV, 6 mg/0.6 mL/dose started within the first 2 hours after birth and continued at 6-hour intervals for 4 to 6 weeks (1997-1998); and (4) intrapartum intravenous ZDV given in addition to regimen 3 (1998-1999). Neonatal ZDV was administered within 2 hours after birth in 95% of the neonates.


RESULTS
In a cohort of 136 children born at least 9 months before the analysis date, the HIV-1 vertical infection rates were: (1) no ZDV, 11 of 48 (22.9%, 95% confidence interval [CI] = 12.0-37.3); (2) late antenatal ZDV, 10 of 47 (21.3%, 95% CI = 10.7-35.7); (3) late antenatal ZDV plus immediate neonatal ZDV, 0 of 28 (0%, 95% CI = 0-12.3); (4) late antenatal, intrapartum intravenous ZDV, plus immediate neonatal ZDV, 0 of 13 (0%, 95% CI = 0-24.7). An estimated 0% (95% CI = 0-8.6) of the infants who received immediate neonatal ZDV with or without intrapartum ZDV were infected, as compared with 22.1% (95% CI = 14.2-31.8 ) of those who received no ZDV or only late antenatal ZDV (P < 0.001).


CONCLUSIONS
The results of this study suggests high protective effect of immediate administration of neonatal ZDV. Perinatal components of antiretroviral prophylaxis provided the best results for protecting against vertical HIV-1 transmission.
Sirinavin S
S
S
Division of Infectious Diseases, Department of Pediatrics, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand. rassr@mahidol.ac.th
Phaupradit
W
W
Taneepanichskul
S
S
Atamasirikul
K
K
Hetrakul
P
P
Thakkinstian
A
A
Panburana
P
P
D000293:Adolescent; D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D018890:Chemoprevention; D005260:Female; D015658:HIV Infections / Q000635:transmission*; D015497:HIV-1; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000821:virology; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use*; D015215:Zidovudine / Q000627:therapeutic use*
D019380:Anti-HIV Agents; D018894:Reverse Transcriptase Inhibitors; D015215:Zidovudine