Outbreak of an acute aflatoxicosis in Tanzania during 2016

Abstract

In June 2016, an outbreak of an unknown disease was reported to affect clusters of families in two regions of the central part of Tanzania. A rapid epidemiological survey was conducted in the affected villages, with a detailed house-to-house survey in selected households. A total of 68 cases occurred between 14 May and 14 November 2016, of which 20 died, making a case fatality rate of 30%. Over 50% of the cases were below the age of 15 years. The cases presented with jaundice (n=60), abdominal pain (n=59), vomiting (n=56), diarrhoea (n=34) and ascites (n=32). The responsible food item appeared to be home grown maize. The rate ratio indicated that the occurrence of illnesses was associated with ingestion of food contaminated with high levels of aflatoxins (contamination range: 10-51,100 μg/kg and 2.4-285 μg/kg for case and control households, respectively). Serum aflatoxin biomarker indicated that cases were more likely to have higher than 1000 pg/mg aflatoxin-albumin adduct level in their sera compared to controls (Odds Ratio = 13.5; 95% confidence intervals = 1.5-165.3; range of aflatoxin-albumin adduct level = 36- 32,800 pg/mg for cases and 10-4020 pg/mg for controls). Beside aflatoxins, maize samples were also contaminated with high levels of fumonisins (range of contamination; 945-12,630 μg/kg) with 8 of 10 samples analysed from case households co-contaminated with both toxins at levels above the maximum limit of 5 or 10 μg/kg set for AFB1 or total aflatoxins and 2,000 μg/kg for fumonisins. Clinical presentation and high levels of aflatoxin in food samples coupled with high levels of serum aflatoxin-albumin adducts among the cases support the causal role of aflatoxins.

Microbiological safety of ready‐to‐eat foods in low‐ and middle‐income countries: A comprehensive 10‐year (2009 to 2018) review

“…On the other hand, continuous daily exposure to single or mixtures of these food contaminants via consumption of contaminated RTEs could produce a plethora of adverse health effects. Observable effects may range from mild to recurrent nausea, vomiting, and diarrhea (Ceuppens et al., ) to severe complications such as cancers, neural tube defects, and even human fatalities (Gibb et al., ; IARC, ; JECFA, , ; Kamala et al., ; Wild & Gong, ). Thus, improperly prepared RTEs in LMICs, where regulations and monitoring for compliance are grossly inadequate, may constitute a huge risk to public health.…”

Aflatoxins: A Comprehensive Overview

“…Of the maize samples contaminated with 571 both mycotoxins, 80% exceeded the regulatory standards of 10 g/kg and 2000 g/kg for total aflatoxins 572 and fumonisins, respectively. Moreover, the titres of aflatoxin-albumin adduct in the serum of case-patients 573 usually exceeded 1000 pg/mg and were 3.6 to 8.2 times higher than in the serum of controls (36-32,800 574 pg/mg vs 10-4020 pg/mg) [187]. The increase in aflatoxin-albumin adduct titre is a strong indication of the 575 causal link between aflatoxins and the outbreak, the severity of which may have been increased by an 576…”

“…showed that more than 50% of the cases were children below 15 years-old who had eaten home-grown 567 maize contaminated with both aflatoxins and fumonisins at abnormally high levels [187]. Aflatoxin 568 contamination in samples collected from case-households was significantly higher than those of controls 569 (10-51,100 g/kg versus 2.4-285 g/kg).…”

“…A recent aflatoxicosis outbreak was reported in the central region of Tanzania in 2016 [187]. The 555 prevailing climate in the region is hot semi-arid (BSh) and subject to frequent alternations of drought and 556 flood periods caused by ENSO [112].…”

Aflatoxins: Production, Structure, Health Issues and Incidence in Southeast Asian and Sub-Saharan African Countries

“…Although there is no consensus on the specific dose of aflatoxins that triggers acute toxicity in humans, it is well established that such a dose is highly variable depending on many factors, including the age, gender, health and nutritional status, presence or absence of underlying factors (e.g. chronic viral hepatitis, alcoholism, smoking, cirrhosis, exposure to hepatotoxic microcystins); and it is lowest in youngsters, as substantiated by the highest death rates of this age-group in aflatoxicosis outbreaks [168][169][170]. A rough estimation of the acute dose of AFB1 concerned a case report on a-15-years old Ugandan child weighing 36 kg who has been eating AFB1-contaminated cassava on a daily basis until he died by liver failure [171].…”