Acute respiratory infections prevent improvement of vitamin A status in young infants supplemented with vitamin A.

Randomized placebo-controlled trial in very young infants aged 6-17 weeks attending an immunization clinic in Dhaka, Bangladesh (ICDDR,B EPI clinic). Infants had recently recovered from diarrhea, and those with active infections such as pneumonia, diarrhea, septicemia, and other illnesses were excluded; morbidity and vitamin A status were followed for about 5 months.

Oral vitamin A was given as 15 mg retinyl palmitate in oil per dose, administered at monthly intervals for 3 doses at 0, 4, and 8 weeks alongside DPT/OPV immunizations. The comparator was placebo (soybean oil).

Vitamin A modestly improved vitamin A status and reduced the duration of acute respiratory infections, but it did not reduce the number of diarrhea or ARI episodes, and many infants remained vitamin A deficient after supplementation. In the vitamin A group, ARI duration was 27.6 ± 17.1 vs 40.8 ± 22.7 days per child-year in placebo (P = 0.005), while ARI episodes per child-year and diarrhea outcomes were not significantly different. In post-supplementation testing, 61% of vitamin A recipients still had RDR > 20 versus 82% of placebo recipients (P = 0.06). Among supplemented infants who remained deficient, ARI burden was higher and fever and cough lasted longer; 10% of infants receiving vitamin A developed bulging fontanelle, and the trial was stopped early.

The trial was stopped early because of bulging fontanelle in 10% of vitamin A recipients, limiting safety interpretation and follow-up. Many infants remained vitamin A deficient despite three large doses, and some outcome analyses were based on small subgroups, including post-supplementation testing in only 61 infants. The setting was a specific high-infection-burden clinic population, which may limit generalizability.