Fig. 4.

Impact of HCQ and AZM alone or combined on lung histological impairments in a Syrian hamster model at 5 dpi.

(a) Experimental timeline (realized on biorender.com). Groups of 4 hamsters were intranasally infected with 1 × 10⁴ TCID₅₀ of SARS-CoV-2, treated from 0 to 3 dpi and sacrificed at 5 dpi (blue arrows). (b) Scores of histopathological changes measured following criteria presented in Supplemental Table 1, as previously described (Driouich et al., 2021). Dashes represent mean scores for each group (n = 4; details in Supplemental Table 5). (c) Representative images of bronchial inflammation (scale bar: 100 μ). From left to right, pictures represent marked neutrophilic bronchitis (high HCQ + AZM animal), mild peribronchial leucocytic infiltration (high HCQ + AZM animal) and no inflammation (mock-infected animal). (d) Representative images of alveolar inflammation (scale bar: 100 μ). From left to right, pictures represent severe interstitial pneumonia (high HCQ animal), marked interstitial changes (high HCQ + AZM animal) and no inflammation (mock-infected animal). (e) Representative images of vessel changes (leukocyte accumulation within vascular walls). From left to right, pictures represent presence (high HCQ animal) and absence of lesions (mock-infected animal) (scale bars: 100 μ). Clinical follow-up is represented in Supplemental Fig. 5.