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Despite increasing associated mortality and morbidity, the diagnosis of fungal infections, especially with <i>Aspergillus fumigatus</i> (<i>A. fumigatus</i>), remains challenging. Based on known ability of <i>Aspergillus</i> species to utilize sorbitol, we evaluated 2-[¹⁸F]-fluorodeoxysorbitol (FDS), a recently described <i>Enterobacterales</i> imaging ligand, in animal models of <i>A. fumigatus</i> infection, in comparison with 2-[¹⁸F]-fluorodeoxyglucose (FDG). In vitro assays showed slightly higher ³H-sorbitol uptake by live compared with heat-killed <i>A. fumigatus</i>. However, this was 10.6-fold lower than <i>E. coli</i> uptake. FDS positron emission tomography (PET) imaging of <i>A. fumigatus</i> pneumonia showed low uptake in infected lungs compared with FDG (0.290 ± 0.030 vs. 8.416 ± 0.964 %ID/mL). This uptake was higher than controls (0.098 ± 0.008 %ID/mL) and minimally higher than lung inflammation (0.167 ± 0.007 %ID/mL). In the myositis models, FDS uptake was highest in live <i>E. coli</i> infections. Uptake was low in <i>A. fumigatus</i> myositis model and only slightly higher in live compared with the heat-killed side. In conclusion, we found low uptake of ³H-sorbitol and FDS by <i>A. fumigatus</i> cultures and infection models compared with <i>E. coli</i>, likely due to the need for induction of sorbitol dehydrogenase by sorbitol. Our findings do not support FDS as an <i>Aspergillus</i> imaging agent. At this point, FDS remains more selective for imaging Gram-negative <i>Enterobacterales</i>.