Immunohistochemical analyses of the neurologic system of C57BL/6 mice exposed to aerosolized Burkholderia pseudomallei strain ATS2021, the causative strain in an outbreak of 4 cases, 2 of them fatal, in the United States in 2021. A) Day 6 after exposure, dose 107 CFU. Cerebrum shows multifocal moderate positivity (arrows). Original magnification ×2. B) Day 6 after exposure, dose 107 CFU. Cerebellum shows multifocal moderate positivity (arrow). Original magnification ×10. C) Day 5 after exposure, dose 1,150 CFU. Lumbar spinal cord at cauda equina and vertebra shows multifocal mild perineural positivity (arrows) of spinal nerves at cauda equina and marked vertebral bone marrow positivity (arrowheads). Original magnification ×10. D) Day 9 after exposure, dose 107 CFU. Spinal cord, cervical, shows focal moderate positivity (arrowheads). Original magnification ×20.