Safety of primaquine in infants with Plasmodium vivax malaria in Papua, Indonesia

BackgroundPrimaquine (PQ) prevents relapses of vivax malaria but may induce severe haemolysis in glucose-6-phosphate dehydrogenase (G6PD) deficient patients. Data on the safety of primaquine in infants are limited.MethodsA retrospective, hospital-based cohort study of infants aged 1-12months with vivax malaria was carried out in Timika, Papua province, Indonesia. Risks of admission, death and severe haematological outcomes within 30days of first presentation were compared between infants who did and did not receive primaquine. Infants were not tested routinely for G6PD deficiency as per local guidelines.ResultsBetween 2004 and 2013, 4078 infants presented to the hospital for the first time with vivax malaria, of whom 3681 (90.3%) had data available for analysis. In total 1228 (33.4%) infants were aged between 1 and 6months and 2453 (66.6%) between 6 and 12months of age. Thirty-three (0.9%) patients received low-dose primaquine (LDP), 174 (4.7%) received high-dose primaquine (HDP), 3432 (93.2%) received no primaquine (NPQ) and 42 patients received either a single dose or an unknown dose of primaquine. The risk of the Hb concentration falling by>25% to less than 5g/dL was similar in the LDP or HDP groups (4.3%, 1/23) versus the NPQ group (3.5%, 16/461). Three infants (1.4%) died following receipt of PQ, all of whom had major comorbidities. Seventeen patients (0.5%) died in the NPQ group. None of the infants had documented massive haemolysis or renal impairment.ConclusionsSevere clinical outcomes amongst infants treated with primaquine in Papua were rare. The risks of using primaquine in infancy must be weighed against the risks of recurrent vivax malaria in early life.