Opportunistic pathogenic filamentous fungal species in health supplements : potential risk to immune compromised individuals

Sammanfattning: Invasive fungal infections (IFI) are a threat to individuals with a suppressed immune system and the rate of IFI cases in the world is increasing. These types of infections occur both at home and during hospitalization. At hospitals, small wounds caused by needles may later be infected with conidia, air-borne opportunistic pathogenic conidia may be inhaled, and contaminated food may be consumed. IFI in the gastrointestinal tract increases the mortality rate due to late detection of those infections. The objective of this study was to investigate if food products that immune suppressed individuals would prefer to buy, or products marketed toward those individuals, would contain any opportunistic pathogenic filamentous fungi. The study also compares if any difference can be found between samples incubated at the temperatures of 25 ºC and 35 ºC, this to simplify any screening of filamentous fungi. Among 16 different products (1 tea, 8 probiotics and 7 plant based products), filamentous fungi were only detected in two leaf powder products, one product of chia seeds, camomile tea, two probiotics and two fruit and vegetable products. The two opportunistic pathogenic species Rhizopus oryzae and Mucor circinelloides were detected in one of the probiotic products incubated at 35 ºC. R. oryzae was also detected in chia seeds together with other opportunistic pathogens, such as Lichtheimia ramosa and Aspergillus flavus when incubated at 35 ºC. Both A. flavus and A. fumigatus was detected in nettle leaf powder and fruit powder incubated at 35 ºC. The fruit powder did however also contain the opportunistic pathogen Byssochlamys spectabilis, and the nettle leaf powder did also contain the opportunistic pathogen R. microsporus. Leaf powder made of Moringa oleifera was the only product that was found to be heavily contaminated with L. ramosa. The study could show that there is a slightly better chance to reduce the growth of non-opportunistic pathogenic species and target only the opportunistic pathogenic species by incubating samples at 35 ºC. To completely avoid growth of non-opportunistic pathogenic species is not possible through this method only.