Pathology and presence of MPXV antigen in lung tissue.

<p>Figures <b>A–D</b> are histological sections of lung tissues from cynomolgus macaques infected via aerosolized MPXV. Positive immunoreactivity for orthopoxvirus antigen, shown as brown staining, is associated with necrotizing lesions primarily concentrated around bronchi and bronchioles. [Immunoperoxidase method using rabbit polyclonal antibody to vaccinia virus; original magnification ×40 (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0012880#pone-0012880-g006" target="_blank">Figure 6A</a>) or ×20 (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0012880#pone-0012880-g006" target="_blank">Figure 6</a> B, C, D)]. <b>A</b>) 4×10⁴ PFU (day 10 post-exposure). <b>B</b>) 1×10⁵ PFU (day 8 post-exposure). <b>C</b>) 4×10⁵ PFU (day 11 post-exposure). <b>D</b>) 1×10⁶ PFU (day 9 post-exposure). <b>E</b>) Percent immunoreactivity in the lungs of non-survivors by dosage group, measured by digital microscopy image analysis.</p

Key histopathologic lesions in cynomolgus macaques exposed to aerosolized MPXV.

<p>* = lesion seen in survivors<b>.</b></p

Serum chemistries in macaques exposed to aerosolized MPXV.

<p>The dotted lines indicate the normal reference range; n: number of animals. Graphs show average <b>A</b>) total protein, <b>B</b>) albumin, <b>C</b>) lactate dehydrogenase (LDH), <b>D</b>) C-reactive protein, <b>E</b>) aspartate transaminase (AST), <b>F</b>) and alanine transaminase (ALT), <b>G</b>) urea nitrogen.</p

Average number of leukocytes and platelets in macaques after exposed to aerosolized MPXV.

<p>The dotted lines indicate the normal reference range; n: number of animals. Graphs are shown for <b>A</b>) total white blood cells (WBC), <b>B</b>) percentage of granulocytes (GR), <b>C</b>) percentage of lymphocytes (LY), <b>D</b>) platelets (PLT) for all MPXV dosage groups, and survivors versus non-survivors (right).</p

Summary of inhaled doses, fever, and disease outcome in cynomolgus macaques exposed to aerosolized MPXV.

a<p>Defined as the first day with >8 h of significant temperature elevation (as determined by ARIMA modeling).</p>b<p>Calculated as the number of days (converted to hours) with 12 or more h of significant temperature elevation.</p>c<p>Calculated as the sum of the significant temperature elevations.</p>d<p>The maximum change in temperature.</p>e<p>Calculated by dividing fever hours by fever duration in hours.</p>f<p>Mean time-to-death.</p