Analysis of Aspergillus spp. Isolates According to Temporal–Spatial, Sociodemographic, and Clinical Variables—Microsatellite Typing of Clinical and Environmental Samples of Aspergillus fumigatus in a University Hospital in Sao Paulo, Brazil

BACKGROUND: Typing Aspergillus species is crucial for understanding the sources of infection in hospital environments. OBJECTIVES: This study analysed clinical and air samples as well as their relationship with the clinical forms of aspergillosis. Additionally, we examined the usefulness of the Short Tandem Repeats (STR) technique with two highly discriminatory markers for analysing the Aspergillus fumigatus (A. fumigatus) profile. PATIENTS/METHODS: Seventy-five air samples (September 2013-July 2014) and 116 clinical samples (2009-2014) were collected in a university hospital. Seventy-two samples were typed by STR with two markers, MC3 and MC5. RESULTS: Of the 75 air samples collected, 10 were positive in the Bone Marrow Transplant unit, a ventilated unit with HEPA filters as were 18 in the Haematology ward, a naturally ventilated unit. Of the 116 clinical samples of Aspergillus spp., 95 were identified as A. fumigatus. High diversity was found, with 42 genotypes in 67 clinical samples and four in five environmental samples. Most isolates were collected during the demolition and renovation of the Emergency unit in the Hospital from 2013 to 2014. Genotype 1 was found in several units during different years. Despite the heterogeneity, identical genotypes were observed three times at short intervals in the same or different wards. Some of these identical genotypes were confirmed as possible clones by genome sequencing while others' genotyping matches failed to be confirmed. CONCLUSION: Despite the diversity of clinical and environmental samples, useful correlations can be established in invasive aspergillosis surveillance programs by using this simple STR method as a preliminary step.