Influenza Outbreak During Exercise Talisman Sabre, Queensland, Australia, July 2019.

Influenza appeared in Queensland, Australia during Exercise Talisman Sabre (TS-19) in July 2019 with an early focus within the New Zealand Defence Force members arriving in Australia aboard HMNZS Canterbury. A total of 76 cases of influenza-like illness (ILI) were reported, of which 43 were confirmed by rapid diagnostic tests to be influenza A (n=32) and B (n=11). Australia's influenza season (starting in March, peaked in July 2019) exposed large numbers of military members to a virus for which they had been suboptimally immunized either because of low uptake of the Southern Hemisphere vaccine by Australians/New Zealanders who were not mandated to be immunized, or because U.S. soldiers had received only the Northern Hemisphere vaccine for the 2018-2019 season. A low-intensity clinical unit separate from the main exercise was used as a means of isolating ILI cases both to facilitate their treatment and limit disease spread. Despite disease rates of <1%, influenza still had a major impact on TS-19 mostly in terms of the considerable medical resources required to manage ILI.

Matrix-assisted laser desorption ionization-time of flight mass spectrometry identification of yeasts is contingent on robust reference spectra.

BACKGROUND: Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for yeast identification is limited by the requirement for protein extraction and for robust reference spectra across yeast species in databases. We evaluated its ability to identify a range of yeasts in comparison with phenotypic methods. METHODS: MALDI-TOF MS was performed on 30 reference and 167 clinical isolates followed by prospective examination of 67 clinical strains in parallel with biochemical testing (total n = 264). Discordant/unreliable identifications were resolved by sequencing of the internal transcribed spacer region of the rRNA gene cluster. PRINCIPAL FINDINGS: Twenty (67%; 16 species), and 24 (80%) of 30 reference strains were identified to species, (spectral score ≥2.0) and genus (score ≥1.70)-level, respectively. Of clinical isolates, 140/167 (84%) strains were correctly identified with scores of ≥2.0 and 160/167 (96%) with scores of ≥1.70; amongst Candida spp. (n = 148), correct species assignment at scores of ≥2.0, and ≥1.70 was obtained for 86% and 96% isolates, respectively (vs. 76.4% by biochemical methods). Prospectively, species-level identification was achieved for 79% of isolates, whilst 91% and 94% of strains yielded scores of ≥1.90 and ≥1.70, respectively (100% isolates identified by biochemical methods). All test scores of 1.70-1.90 provided correct species assignment despite being identified to "genus-level". MALDI-TOF MS identified uncommon Candida spp., differentiated Candida parapsilosis from C. orthopsilosis and C. metapsilosis and distinguished between C. glabrata, C. nivariensis and C. bracarensis. Yeasts with scores of <1.70 were rare species such as C. nivariensis (3/10 strains) and C. bracarensis (n = 1) but included 4/12 Cryptococcus neoformans. There were no misidentifications. Four novel species-specific spectra were obtained. Protein extraction was essential for reliable results. CONCLUSIONS: MALDI-TOF MS enabled rapid, reliable identification of clinically-important yeasts. The addition of spectra to databases and reduction in identification scores required for species-level identification may improve its utility.