Health economic impacts and cost-effectiveness of aflatoxin-reduction strategies in Africa: case studies in biocontrol and post-harvest interventions

Abstract

Advances in health economics have proven useful in evaluating the cost-effectiveness of interventions, where the benefit usually takes the form of improved health outcomes rather than market outcomes. We perform health-based cost-effectiveness analyses of two potential aflatoxin control strategies in Africa: 1) pre-harvest biocontrol, using atoxigenic strains of Aspergillus flavus to competitively exclude toxigenic strains from colonizing maize in Nigeria, and 2) postharvest interventions in a package to reduce aflatoxin accumulation in groundnuts in Guinea. We describe how health benefits gained from each intervention, in terms of fewer aflatoxininduced hepatocellular carcinoma (HCC) cases, can be compared with costs of implementing the interventions. We find that both interventions would be extremely cost-effective if applied widely in African agriculture. That is, the monetized value of lives saved and quality of life gained by reducing aflatoxin-induced HCC far exceeds the cost of either biocontrol or the postharvest intervention package to achieve those health benefits. The estimated cost-effectiveness ratio (CER; gross domestic product multiplied by disability-adjusted life years saved per unit cost) for biocontrol in Nigerian maize ranges from 5.10 to 24.8; while the estimated CER for the postharvest intervention package in Guinean groundnuts ranges from 0.21 to 2.08. Any intervention with a CER greater than 1 is considered by the World Health Organization to be "very cost-effective," while an intervention with a CER greater than 0.33 is considered "cost-effective." Aside from cost-effectiveness, public health interventions must be readily accepted by the public, and must have financial and infrastructural support to be feasible in the parts of the world where they are most needed.

Changes in Fungal Population and Aflatoxin Levels and Assessment of Major Aflatoxin Types in Stored Peanuts (Arachis hypogaea Linnaeus)

“…Suboptimal postharvest conditions including handling, storage and processing have been suspect in playing a major role in aflatoxin accumulation in food crops within developing countries (Wu & Khlangwiset, 2010). Most households and traders in Kenya prefer polypropylene and polyethylene bags for packaging and storing peanuts with less than 1% of the traders storing their products in the recommended jute bags .…”

“…Peanuts and maize are the most susceptible crops to aflatoxin contamination (Wu & Khlangwiset, 2010). The two crops and their products are widely consumed in Kenya.…”

Occurrence of aflatoxin in agricultural produce from local markets in Burundi and Eastern Democratic Republic of Congo

“…There are four major aflatoxins, including B 1 , B 2 , G 1 , and G 2 ; however, aflatoxin‐B 1 is the most toxic and prevalent and is classified as a Group 1A carcinogen by the International Agency for Research on Cancer (IARC 2002). High‐dose exposure to aflatoxins concentrations can cause acute health effects such as vomiting, abdominal pain, and even possible death (Probst, Njapau, & Cotty, 2007; Sherif, Salama, & Abdel‐Wahhab, 2009), while sublethal chronic exposure may lead to liver cancer, stunting in children, and immune system suppression (Chan‐Hon‐Tong, Charles, Forhan, Heude, & Sirot, 2013; Wu & Khlangwiset, 2010). In 1981, for instance, the outbreak of aflatoxicosis as a result of ingestion of maize contaminated with 3.2–12 mg/kg of aflatoxin‐B 1 caused fatalities in Kenya (Obura, 2013).…”

Aflatoxin Contamination in Foods and Feeds: A Special Focus on Africa

“…In order to determine the cost effectiveness of various interventions, it is necessary to establish the cost effectiveness ratio (CER), which is the gross domestic product (GDP) multiplied by DALY saved per unit cost. In a study involving AF in maize in Nigeria and groundnut in Guinea, two strategies were compared viz: pre-harvest control; and post harvest interventions (Wu and Khlangwiset, 2010a). Accordingly, it was shown that the cost of both interventions exceeded the monetised values of lives saved and quality of life gained by reducing HCC, if applied nationwide.…”