El Nino and Aflatoxicosis

Summary

Liver Cancer is one of the leading causes of cancer deaths globally, primarily affecting populations in low and middle-income countries (LMICs). Aflatoxin, a food contaminant produced by the fungi Aspergillus species, is a known human carcinogen that has been demonstrated to cause the pathogenesis of Liver cancer. Several determinants affect the propagation of fungi and the grade of Aflatoxin contamination in food. Drought stress is one of the factors that increase the vulnerability of plants to fungi and hence Aflatoxin contamination.

Aflatoxicosis is the outcome of exposure to aflatoxins and may be acute or chronic. Acute exposure can cause fatalities in humans and livestock. Chronic exposure results in liver cancer and lowered immunity. Aflatoxins are biochemicals produced by fungi known as Aspergillus.

There are several Aspergillus species that occur in nature. Examples of Aspergillus include; Aspergillus nomius, A. flavus, A. parasiticus and A. pseudonomius. The most harmful forms of Aflatoxins are synthesized by A. parasiticus and A. flavus. Aflatoxins are classified according to the color that they produce in UV light. For instance, Aflatoxins that have been characterized using this methodology include Aflatoxin B1 (AfB1), Aflatoxin B2, Aflatoxin G1 and Aflatoxin G2. The B and G stand for Blue and green respectively. These fungi are common in many tropical regions such as Africa, and studies have reported their global public health impacts. For instance, in 1974 in India, in 2004 in Kenya, in 2012 in the USA, in 2016 in Kenya, and in 2019 in Kenya. Aspergillus fungi are common flora that are found on many food crops and decaying plant matter. Studies have reported the presence of Aflatoxins in foods such as Cereals and fruits. The effects of Aflatoxins are subtle and are largely unreported since many cereals are not subjected to quality standards assessment. This is mainly due to the production and consumption of cereal crops outside the operational reach of the quality standards organizations. Consequently, many cases of Aflatoxin exposure are either unreported or misreported. The tradeoffs of this scenario act in synergy with poverty to intensify undesirable health outcomes within consumer populations. It has also been noted that Aflatoxins are common in the diet of low-income populations. This is mainly due to the low hygiene standards in many informal settings. El Nino weather phenomenon is likely to engender elevated levels of moisture in domestic settings, stores, and food processing facilities. Additionally, the handling of foodstuff and public health policing are undermined by logistical limitations and high insecurity. Consequently, poverty has a tributary effect on aflatoxin pathogenesis, since is creates an environment in which aflatoxins and other disease-causing agents work synergistically to realize disease.

Aflatoxin exposure causes varying degrees of health impacts depending on age. Adults are less likely to suffer acute exposure from small doses. However, children due to their small body sizes are likely to have acute toxicity even with small doses of exposure. As such, studies have reported associations between aflatoxicosis in children and childhood malnutrition. Kwashiorkor and Reye Syndrome for instance, have been demonstrated to be common in children consuming Aflatoxin contaminated foods. Since the classic features of these diseases are known, the long-term impacts of failure to curtail aflatoxicosis warrants urgent action. Several interventions have been suggested by researchers, such as approaches targeting farming practices, pre-harvesting, harvesting and post-harvesting hygiene and standard procedures. Beyond the mentioned approaches, foods acquire aflatoxins during transportation and storage. Therefore, sensitization on the natural history of Aspergillus should be undertaken amongst the public. On their part, the governmental institutions are obligated to inspect food handling facilities to ensure compliance with national and regional food quality standards. Finally, funding is necessary to provide impetus for research.  

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