The hard-to-treat condition causes ague symptoms such as cough and shortness of breath, but steadily worsens, the CDC said in its weekly report on death and disease.

• 疾病控制和预防中心在每周的死亡和疾病报告中指出，这种疾病很难治疗，可以出现咳嗽和呼吸急促等症状，而且不断恶化。