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Shewanella algaeis a rod-shaped Gram-negative marine bacterium frequently found in nonhuman sources such as aquatic ecosystems and has been shown to be the pathogenic agent in various clinical cases due to the ingestion of raw seafood. The results of this study showed thatS. algaewas present in approximately one in four samples, including water and shellfish samples. Positive reactions (API systems) inS. algaestrains were seen for gelatinase (gelatin); however, negative reactions were found for indole production (tryptophan).S. algaeis adapted to a wide range of temperatures (4°C, 25°C, 37°C, and 42°C) and salinity. Temperature is a key parameter in the pathogenicity ofS. algaeas it appears to induce hemolysis at 25°C and 37°C.S. algaeexhibits pathogenic characteristics at widely varying temperatures, which suggests that it may have the ability to adapt to climate change.

Background Shewanella algae has been recognized as an emerging human pathogen. However, not much is known about the mechanism of its pathogenesis and its adaptation to a special niche such as the hepatobiliary tract. Results In this study, we isolated the S. algae ACCC strain from human bile and performed whole genome sequencing. S. algae ACCC consists of a circular 4,743,354-bp chromosome with a GC content of 53.08%, within 4080 protein coding sequences. The genome of strain ACCC contains a number of candidate genes which have been reported to be associated with bile adaption, including htpB, exbBD, wecA, galU, adeFGH and phoPQ regulon. Conclusions Our results highlight the association of S. algae with a rare disease profile. Further studies are needed to shed light on the evolution of pathogenesis and the niche adaptation of S. algae.

Shewanella haliotisis an emerging human pathogen. Many infectious cases were linked to shellfish ingestion or aquatic exposure. Therefore, it is important to study the phylogeny and distribution ofS. haliotisin shellfish aquaculture. We investigated the distribution ofS. haliotisin cultivated shellfish farming in Taiwan in whichS. haliotiswas found in the shellfish from all sampling sites.S. haliotiswas identified in cultivated shellfish by 16S rRNA gene sequencing, such as abalone (Haliotis diversicolor), clam (Meretrix lusoria), and oyster (Crassostrea gigas). This study highlighted the contamination ofS. haliotisin cultivated shellfish and importance of further study regarding the biodiversity and pathogenesis ofS. haliotis.

Recent reports have shown that food‐borne or commensal bacteria can function as reservoirs of antibiotic resistance. However, the antibiotic susceptibility of bacterial isolates of most milk samples or the total bacterial counts (TBC) in human milk from healthy donors, are not fully understood in Taiwan. Thus, five healthy mothers were randomly recruited each month, and totally 30 mothers without any symptoms of infection were recruited over 6 months. Milk samples were then harvested and analyzed immediately after collection. The antibiotic susceptibility was analyzed in bacteria isolated from milk samples using nine clinically relevant antibiotics, such as oxacillin, ampicillin, cephalothin, amoxicillin, ciprofloxacin, erythromycin, clindamycin, gentamicin, and oxytetracycline. The Staphylococcus strains (48 isolates) found in milk resisted to 48.6 ± 20.1% selected antibiotics. Streptococcus‐related isolates (8 isolates) exhibited resistance to 41.7 ± 26.4% selected antibiotics. Acinetobacter isolates (5 isolates) were resistant to 66.7 ± 13.6% antibiotics, and Enterococcus isolates (5 isolates) were resistant to 73.3 ± 6.1% tested antibiotics. Rothia‐related isolates (4 isolates) were resisted to 58.2 ± 31.9% of tested antibiotics. In contrast, Corynebacterium isolates (5 isolates) were sensitive to 66%–100% of selected antibiotics. Furthermore, the TBC ranged from 40 to 710,000 CFU/ml, implying a wide spectrum of bacteria in milk from healthy mothers. Despite this, all milk donors were healthy during sampling, and they did not show any symptoms related to mastitis or subclinical mastitis. According to the previously described TBC criteria for the use of donated human milk, only 73% of the current milk samples could be accepted for the milk bank. In conclusion, the majority of the isolated bacterial strains from current human milk samples are multiresistant strains. In milk samples for preterm infants or milk banks, higher TBC levels or potentially antibiotic‐resistant bacteria in some milk samples have supported people using approaches to disinfect human milk partially.