A cytokine storm, or the upregulation of proinflammatory cytokines and chemokines, such as IL-6, IL-8, IFN-α, IP-10, MIG, MIP-1β, and MCP-1, is reported to have contributed to the lung injury and severe pneumonia in these H7N9-infected patients [5], [7]. Here, CXCL9 is linked to susceptibility to pneumonia measurement.