Impact of hookworm infection and preventive chemotherapy on haemoglobin in non-pregnant populations.

OBJECTIVE To assess the impact of hookworm infection and preventive chemotherapy on haemoglobin levels in non-pregnant populations in endemic areas. METHOD Systematic review and meta-analysis searching PubMed and Web of Science for articles published since 2010 reporting either hookworm prevalence and Hb concentration (cross-sectional studies), or Hb concentration before and after the implementation of preventive chemotherapy (before-after studies and randomised controlled trials [RCTs]). For papers published before 2010, data were extracted from a previously published systematic review. Random effects meta-analyses were conducted to examine the relationship between Hb concentration and hookworm infection intensity (from cross-sectional studies) and the effect of preventive chemotherapy on Hb concentration (from before-after studies and RCTs). Sensitivity analyses investigated the impact of malaria endemicity and combined interventions for schistosomiasis and nutrition status on Hb concentration. RESULTS Among cross-sectional studies, both light- and heavy- intensity hookworm infections were associated with lower Hb in school-aged children. School-aged children with heavy hookworm infection in settings of high malaria endemicity had lower mean Hb than those in settings of low malaria endemicity. In non-pregnant populations, deworming with albendazole was associated with an increase in Hb of 3.02 g/L (95% CI 0.1, 6.0g/L). No additional benefit was seen with deworming using albendazole co-administered with praziquantel for schistosomiasis infection or iron supplementation for nutrition status. CONCLUSION Our findings confirm the benefits of preventive chemotherapy as a public health intervention.