Weissella strains are currently being used for biotechnological and probiotic purposes [1]. While, Weissella hellenica found in flounder intestine had probiotic effects [2], certain species from this genus are opportunistic pathogens in humans. Apart from being implicated in disease in farmed rainbow trout [3], Weissella has been found to cause the following disease in humans.1. endocarditis [4,5]2. bacteraemia [6]3. prosthetic joint infection [7]Whole genome sequences ‘find several virulence determinants such as collagen adhesins, aggregation sub- stances, mucus-binding proteins, and hemolysins in some species’, as well as antibiotic resistance-encoding genes [8]. Caution is warranted in selecting of Weissella strains as starter cultures or probiotics, if at all, since the other option, Lactobacillus, are rarely involved in human disease.Here, the analysis of the lung microbiota in critically ill trauma patients suffering from acute respiratory distress syndrome [9] shows (Accid:ERR1992912) shows complete colonization of Weissella (Fig 1). While, the study mentions ‘significant enrichment of potential pathogens including Streptococcus, Fusobacterium, Prevotella, Haemophilus and Treponema’, there is no reference to the Weissella genus. The percentages of Weissella strains are :confusa=81, soli=7 ,hellenica=5 ,diestrammenae=2. I believe this is the first reported case of Weissella causing ARDS in humans.
