Longitudinal Collection of Burkholderia pseudomallei

Two B. pseudomallei isolates were longitudinally collected from any positive specimens of each melioidosis patient at two time points: on the first day of enrolment (first isolate) and on the day of the recurrent or persistent episode (second isolate). The identification of B. pseudomallei was performed in the microbiology laboratory at each hospital using culture, Gram staining, immunofluorescence assay (IFA), latex agglutination, and standard biochemical tests (Duval et al., 2014 (link); Dulsuk et al., 2016 (link)). The bacterial identification was confirmed at the Faculty of Tropical Medicine, Mahidol University, using Matrix-Laser Absorption Ionization Mass Spectrometry (MALDI-TOF MS) as previously described (Suttisunhakul et al., 2017 (link)). Bacteria were sub-cultured on Ashdown agar plates, incubated at 37°C overnight, and stored at −80°C in trypticase soy broth containing 20% glycerol.