A new study has assessed the ability of oral zinc supplementation (10 mg per day for 12 months) to prevent infection in African children with sickle cell anemia (SCA), a form of sickle cell disease (SCD), and found it ineffective. Furthermore, the study, published in Blood Advances, found that zinc deficiency persisted in 41% of the participants undergoing supplementation.

“Data from small clinical trials in the USA and India suggest zinc supplementation reduces infection in adolescents and adults with [SCA], but no studies of zinc supplementation for infection prevention have been conducted in young children with SCA living in Africa, who have higher infection rates,” the authors wrote. “We conducted a randomized double-blind placebo-controlled trial to assess the effectiveness of zinc supplementation for prevention of severe or invasive infections in Ugandan children 1.00-4.99 years with SCA.”

The research team enrolled 252 children with SCA and randomized 124 to receive 10 mg zinc daily for 1 year and 126 to receive placebo once daily for 1 year. The primary outcome measure was the incidence rate of severe or invasive infections, as defined by the protocol.

The results revealed no difference in rates of infection between the treatment arms: 282 infections per 100 person years in the zinc arm vs 270 infections in the placebo arm.

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There was also no difference between the groups in terms of the incidence of SCA-related events or serious adverse events.

Furthermore, in the participants receiving zinc, although serum zinc levels increased over the 12 months, 41% still had zinc deficiency (<65 μg/dL) at the end of the study. However, the post-hoc analysis did reveal a reduced occurrence of stroke or death in the group receiving zinc supplementation.

The authors conclude that appropriate zinc dosage levels and whether zinc could play a role in the prevention of stroke or death in SCA remain to be further studied.


Namazzi R, Opoka RO, Conroy AL, et al. Zinc for infection prevention in children with sickle cell anemia: a randomized double-blind placebo-controlled trial. Blood Adv. Published online February 3, 2023. doi:10.1182/bloodadvances.2022008539