Assessment of microbiological quality of herbal preparations used in the treatment of malaria, cough and HIV in Kampala district

Abstract

In Uganda, herbal medicine is widely used in the treatment and prevention of various conditions including cough, malaria and HIV opportunistic infections. The demand for herbal products has increased among many consumers who now use herbal on the daily basis to prevent various conditions. The perception that herbal products are safe simply because they are not synthetic has contributed to the overlooking of the element of safety monitoring. Currently, herbal products have been launched on the market with minimal quality and safety evaluation due to limitation in their regulatory framework. There is still limited information regarding the microbiological quality of Herbal products yet consuming highly contaminated herbal preparation could be a public health threat which could increase the morbidity or mortality of their consumers.

We conducted a crossectional study involving identification commonly sold herbal products for the treatment of malaria, cough and HIV related opportunistic infection and assessing their microbiological quality. The study evaluated 30 commonly sold herbal preparation (22 liquids herbal preparation and eight solid herbal preparations) for microbial contamination in accordance to World Health Organisation and United States Pharmacopoeia microbiological limit tests for enumeration and identification.

In this study fifteen microorganisms were identified, the most recurrent being Clostridium species and Aspergillus species. Total bacterial counts (TBC) ranged from an estimated 3.3x101 colony forming units (CFU)/g to 1.3 × 107 CFU/g. Salmonella counts ranged from an estimated <10 CFU/g to 4.0 × 102 CFU/g. E. coli load ranged from <10 CFU/g to 4.3 × 102 CFU/g. Pseudomonas counts ranged from <10 CFU/g to 1.3x103 and S. aureus counts ranged from an estimated <10 CFU/g to 3.4 × 103 CFU/g. Yeast and mould counts ranged from an estimated <10 CFU/g to 3.6 × 106 CFU/g. An evaluation using the World Health Organization limits for medicinal herbs found a percentage of samples to contain microorganisms above allowable limits: 27% (TBC), 23% (Salmonella), 37% (E. Coli) and 70% (yeast and moulds). A total of 40% and 20% of samples contained S. aureus and Pseudomonas loads respectively above the United States Pharmacopeia standard.