A Longitudinal Cohort to Monitor Malaria Infection Incidence during Mass Drug Administration in Southern Province, Zambia

• Published in: The American journal of tropical medicine and hygiene Vol. 103; no. 2_Suppl; pp. 54 - 65
• Main Authors: Bennett, Adam, Porter, Travis R, Mwenda, Mulenga C, Yukich, Joshua O, Finn, Timothy P, Lungu, Chris, Silumbe, Kafula, Mambwe, Brenda, Chishimba, Sandra, Mulube, Conceptor, Bridges, Daniel J, Hamainza, Busiku, Slutsker, Laurence, Steketee, Richard W, Miller, John M, Eisele, Thomas P
• Format: Journal Article
• Language: English
• Published: United States The American Society of Tropical Medicine and Hygiene 01.08.2020
• Subjects: Adolescent; Antimalarials - administration & dosage; Antimalarials - therapeutic use; Artemisinins - administration & dosage; Artemisinins - therapeutic use; Child; Child, Preschool; Disease Eradication - methods; Disease Eradication - statistics & numerical data; Drug Therapy, Combination; Family Characteristics; Female; Humans; Incidence; Longitudinal Studies; Malaria, Falciparum - drug therapy; Malaria, Falciparum - epidemiology; Malaria, Falciparum - prevention & control; Male; Mass Drug Administration - methods; Mass Drug Administration - statistics & numerical data; Quinolines - administration & dosage; Quinolines - therapeutic use; Young Adult; Zambia - epidemiology; Zambia
• ISSN: 0002-9637; 1476-1645
• DOI: 10.4269/ajtmh.19-0657

Rigorous evidence of effectiveness is needed to determine where and when to apply mass drug administration (MDA) or focal MDA (fMDA) as part of a malaria elimination strategy. The Zambia National Malaria Elimination Centre recently completed a community-randomized controlled trial in Southern Province to evaluate MDA and fMDA for transmission reduction. To assess the role of MDA and fMDA on infection incidence, we enrolled a longitudinal cohort for an 18-month period of data collection including monthly malaria parasite infection detection based on polymerase chain reaction and compared time to first infection and cumulative infection incidence outcomes across study arms using Cox proportional hazards and negative binomial models. A total of 2,026 individuals from 733 households were enrolled and completed sufficient follow-up for inclusion in analysis. Infection incidence declined dramatically across all study arms during the period of study, and MDA was associated with reduced risk of first infection (hazards ratio: 0.36; 95% CI: 0.16-0.80) and cumulative infection incidence during the first rainy season (first 5 months of follow-up) (incidence rate ratio: 0.34; 95% CI: 0.12-0.95). No significant effect was found for fMDA or for either arm over the full study period. Polymerase chain reaction infection status at baseline was strongly associated with follow-up infection. The short-term effects of MDA suggest it may be an impactful accelerator of transmission reduction in areas with high coverage of case management and vector control and should be considered as part of a malaria elimination strategy.