Geoclimatic Influences on Invasive Aspergillosis after Hematopoietic Stem Cell Transplantation

Abstract

Background Aspergillus species are ubiquitous. We hypothesized that climatic variables that affect airborne mold counts affect the incidence of invasive aspergillosis (IA). Methods Patients who received hematopoietic stem cell transplants (HSCTs) in geographically and climatically diverse regions (Seattle, WA, and Houston, TX) were examined. Cumulative incidence function, Kaplan-Meier analysis, and Cox proportional hazards regression were performed to examine the association between IA and season. Poisson regression analysis was performed to evaluate the seasonal patterns in IA rates and association with spore counts and climate. Results In Seattle, the 3-month incidence of IA was 4.6% (5.7% in allograft recipients and 0.8% in autograft recipients). During the 10-year study period, there was a decrease in the incidence of IA among allogeneic HSCT recipients, corresponding to decreased risks during the nonsummer months; receipt of HSCTs during the summer months was associated with an increased hazard for IA (hazard ratio, 1.87; 95% confidence interval, 1.25–2.81) after adjustment for other known risks. The person-month IA rate in Seattle was positively associated with environmental spore counts, which increased with high temperature and low precipitation. No seasonal effect on IA was observed in Houston, where total spore counts were lower and not variable by climate. Conclusions Climatic variables differentially affect airborne spore counts and IA risk in geographically disparate centers.

Mucormycosis Caused by Unusual Mucormycetes, Non-Rhizopus, -Mucor, and -Lichtheimia Species

“…Also, very few reports of traumatic mucormycosis caused by unusual Mucormycetes species after natural disaster have been published (19,313), but an epidemiological history of exposure to contaminated ground is a hallmark of traumatic mucormycosis caused by several unusual Mucormycetes species (Table 2). Besides geography and climate, other factors, such as temperature, light, air pollutants, and factors related to human activity, affect the risk of environmental mold contamination (5,17,39,117,142,269,289,310), and probably the risk of infection (247,348). Environmental studies specific for Mucormycetes species are also still scarce (5,28,289).…”

Clinical Manifestation and Diagnosis of Invasive Fungal Sinusitis in Patients with Hematological Malignancy

“…in summer. Some evidence showed that summer months are associated with the highest risk of IFS (21)(22)(23). Moreover, in the present study patients with positive culture results were in an older section of the hospital adjacent to a building construction site that created great amounts of dust in the hospital vicinity.…”

Update on lung transplantation: programmes, patients and prospects

“…The LTR is therefore always at risk from inhaling the conidia of Aspergillus and there is evidence that this is more likely in the setting of building-associated earthwork and seasonal factors [258]. In addition, some patients such as those with CF may be chronically colonised with Aspergillus in their native airway.…”