The majority of the affected experience only the typical flu symptoms of sore throat, headache and fewer, especially during the first case. However, during the second case, disease was more serious, often complicated by bacterial pneumonia, which was often the cause of death. This more serious type could cause hellotrope cycanosis to develop whereby the skin would first develop two mahogany spots over the cheekbones which would then over the few hours spread to color the entire face blue followed by black coloration first in the extremities and then further spreading to the limbs and torso. After this, death would follow within a hours or few days coz of lungs would filled with fluid. Other signs and symptoms reporting included spontaneous mouth and nosebleeds, miscarriages for pregnant women, a peculiar smell, teeth, hair falling, dizziness, insomnia, loss of hearing and smell, blurred vision, impaired color vision.
The majority of deaths were from bacterial pneumonia, a common secondary symptoms associated with influenza. The pneumonia by itself caused common upper respiratory-tract bacteria, which were able to get into the lungs via the damaged bronchial tubes of the victims. The virus also killed the people directly by causing massive hemorrhages and edema in the lungs. Modern analysis shows the virus is particularly deadly coz it triggers a cytokine storms (overreaction of the body's immune system). The animal suffered rapidly progressive respiratory system and death through the cytokine storm. The strong immune systems of young adults were postulated to have ravaged the body, whereas the weaker immune reaction of children and middle-aged young adults resulted in fewer deaths in those groups.