Which symptom appears in the manifest stage of ARS?

The manifest stage of Acute Radiation Syndrome (ARS) occurs after the initial symptoms of the prodromal stage, which typically include nausea and vomiting. During the manifest stage, the severity of symptoms increases and the body begins to show more significant damage from radiation exposure.

Severe weakness, hemorrhage, and infection are critical symptoms that characterize this stage. In the manifest phase, individuals may experience a drop in blood cell production, leading to conditions such as severe infections due to a weakened immune system and hemorrhaging due to reduced platelets. The impact on the bone marrow and other vital organs during this stage is pronounced and can be life-threatening.

In contrast, symptoms such as fatigue and headaches, while they might appear, are often associated with earlier or less severe conditions and may not reflect the significant physiological response seen in the manifest stage of ARS. Thus, the presence of severe weakness, hemorrhage, and infection is indicative of the body’s acute response to high-dose radiation exposure during the manifest stage.