Toxicoepidemiology in Zimbabwe: pesticide poisoning admissions to major hospitals.

Background: Acute pesticide poisoning (APP) is a well-recognized cause of morbidity and mortality but is not well described in developing countries. We describe the toxicoepidemiology of APP in Zimbabwe.

Methods: All cases of APP admitted to eight major referral hospitals in Zimbabwe from January 1998 to December 1999 (inclusive) were identified using ICD-9 codes and ward registers and relevant information recorded on a standard data collection sheet.

Results: There were a total of 914 single pesticide exposures. Almost half (49.1%) resulted from oral exposure to rodenticides, 42.2% from anticholinesterase-type pesticides (AChTP), mostly organophosphates (OP) that were responsible for over 90% of admissions from AChTP. Accidental and deliberate self-poisoning (27.1% and 58.6%, respectively) accounted for most cases with only eight homicides. The case fatality rate (CFR) in deaths/100 admissions was 6.8 [62 deaths; 95% Confidence Interval (CI) 5.2-8.6] and was significantly higher in males (9.4) than females (4.1) (CI for difference in proportions; 2.0-8.5). In addition, the CFR for deliberate self-poisoning (DSP), 6.5 deaths/100 admissions, was also significantly higher than that for accidental poisoning (0.8 deaths/100 admissions) (CI for difference in proportions 3.2-7.9). Organophosphates were implicated in 70.9% of all fatalities, with over 20% resulting from oral exposure to rat poison (RP).

Conclusion: Organophosphates and rat poison (RP) are the leading causes of APP admissions to major referral hospitals in Zimbabwe, with most of the admissions being the result of deliberate self-poisoning. Greater control in the sale and use of these products could help prevent significant morbidity and mortality.