A nosocomial Pseudomonas aeruginosa ST3495 isolated from a wild Burmese python (Python bivittatus) with suppurative pneumonia and bacteremia in Hainan, China

Pseudomonas aeruginosa is a common infectious agent associated with respiratory diseases in boas and pythons, however, the histopathology, resistance and virulence are yet described for this species. In this study, we investigated a dying Burmese python rescued from tropical rainforest in Hainan. Clinical signs were open-mouthed breathing, abnormal shedding and anorexia. Abundant yellow mucopurulent secretions were observed in highly ectatic segmental bronchi by postmortem. Histopathological lesions included systemic pneumonia, enteritis, nephritis and carditis. P. aeruginosa was the only species isolated from heart blood, kidney, trachea and lung. The phenotype analysis demonstrated that the isolates had strong biofilm, and were sensitive to amikacin, spectinomycin, ciprofloxacin, norfloxacin and polymyxin B, moreover, the LD 50 of the most virulent isolate was 2.22×10 5 cfu/mL in a zebrafish model. Molecular epidemiological analysis revealed that the isolates belonged to sequence type 3495, the common gene patterns were tox A + exo SYT + phz IM + plc HN in virulence and cat B + bla TEM + ant (3'')-I+ tet A in resistance. This study highlights that P. aeruginosa should be worth more attention in wildlife conservation and raise the public awareness for the cross infection and cross spread between animals and human. Highlights • Epidermal cells of multiple organs were invaded by Pseudomonas aeruginosa in the wild Burmese python. • Common gene patterns in the isolates were toxA + exoSYT + phzIM + plcHN for virulence and catB + blaTEM + ant (3'')-I + tetA for resistance. • Biofilm was necessary for virulence of the isolates infection in a zebrafish model.