Elevated Blood Lead Levels Are Associated with Reduced Risk of Malaria in Beninese Infants

Violeta Moya-Alvarez (1, 2) , Michael Osei Mireku (1, 2) , Pierre Ayotte (3, 4, 5) , Michel Cot (6, 1) , Florence Bodeau-Livinec (7, 8, 9, 10)

1 MERIT - UMR_D 216 - Mère et enfant en milieu tropical : pathogènes, système de santé et transition épidémiologique
2 iPLESP - Institut Pierre Louis d'Epidémiologie et de Santé Publique
3 DMPS - Département de médecine sociale et préventive
4 Axe santé des populations et pratiques optimales en santé
5 Direction de la Santé Environnementale et de la Toxicologie
6 Facultés des sciences pharmaceutiques et biologiques
7 CRESS - U1153 - Equipe 1 : EPOPé - Épidémiologie Obstétricale, Périnatale et Pédiatrique
8 METIS - Département Méthodes quantitatives en santé publique
9 DHU Risques Et Grossesse
10 EHESP - École des Hautes Études en Santé Publique [EHESP]

Introduction Elevated blood lead levels (BLL) and malaria carry an important burden of disease in West Africa. Both diseases might cause anemia and they might entail long-term consequences for the development and the health status of the child. Albeit the significant impact of malaria on lead levels described in Nigeria, no evaluation of the effect of elevated BLL on malaria risk has been investigated so far. Materials and Methods Between 2010 and 2012, blood lead levels of 203 Beninese infants from Allada, a semi-rural area 50km North from Cotonou, were assessed at 12 months of age. To assess lead levels, blood samples were analyzed by mass spectrometry. In parallel, clinical, microbiological and hematological data were collected. More precisely, hemoglobin, serum ferritin, CRP, vitamin B12, folate levels, and Plasmodium falciparum parasitemia were assessed and stool samples were also analyzed. Results At 12 months, the mean BLL of infants was 7.41 μg/dL (CI: 65.2; 83), and 128 infants (63%) had elevated blood lead levels, defined by the CDC as BLL>5 μg/dL. Lead poisoning, defined as BLL>10 μg/dL, was found in 39 infants (19%). Twenty-five infants (12.5%) had a positive blood smear at 12 months and 144 infants were anemic (71%, hemoglobin<110 g/L). Elevated blood lead levels were significantly associated with reduced risk of a positive blood smear (AOR = 0.38, P-value = 0.048) and P. falciparum parasite density (beta-estimate = -1.42, P-value = 0.03) in logistic and negative binomial regression multivariate models, respectively, adjusted on clinical and environmental indicators. Conclusion Our study shows for the first time that BLL are negatively associated with malarial risk considering other risk factors. Malaria is one of the main causes of morbidity and mortality in infants under 5 years worldwide, and lead poisoning is the 6th most important contributor to the global burden of diseases measured in disability adjusted life years (DALYs) according to the Institute of Health Metrics. In conclusion, due to the high prevalence of elevated BLL, health interventions should look forward to minimize the exposure to lead to better protect the population in West Africa.

Domaines: Maladies infectieuses

Violeta Moya-Alvarez, Michael Osei Mireku, Pierre Ayotte, Michel Cot, Florence Bodeau-Livinec. Elevated Blood Lead Levels Are Associated with Reduced Risk of Malaria in Beninese Infants. PLoS ONE, 2016, 11 (2), pp.e0149049. ⟨10.1371/journal.pone.0149049⟩. ⟨hal-01284375⟩