The contribution of banknotes to microbial contamination and transmission on grilled meat in Dodoma City, Tanzania

Abstract

This study examines the transmission of germs from banknotes to grilled meat sold by street vendors. 100 banknotes and 100 grilled meat samples from 40 street vendors were analyzed and compared with the Tanzania Food Drugs Authority (TFDA) and the East African food standards (EAS) standards. Microbial contamination was higher on banknotes than on meat. Contamination of banknotes and grilled meat by Escherichia coli (28.2%, 9.5%), Salmonella spp. (11.9%, 5.7%), and Staphylococcus aureus (21.3%, 6.8%) was observed. The mean microbial load on banknotes and grilled meat ranged from 5.2 ± 1.31 x 10³ CFU to 5.9 ± 1.23 x 10³ CFU and from 5.1 ± 1.44 x 10³ CFU to 5.4 ± 1.13 x 10³ CFU, respectively. These levels were higher than the EAS 128:2011 and EAS 44:2011 standards. Fungal genera identified in banknotes by ITS PCR and 18S rDNA RT-PCR, were Aspergillus spp. (5%), and Penicillium spp. (3%), with no fungi found on grilled meat. Vendors with informal education and poor hygiene practices had higher contamination levels. Hygiene practices involved regular handwashing (40%), using clean water for meat preparation (55%), covering meat with clean covers (50%), disinfecting cooking equipment (35%), and avoiding raw meat and ready-to-eat meat contact (45%) aimed to reduce contamination. These results call for the need for improved hygiene education and interventions in street food vending.