Local Symptoms
The bite wound typically has mild pain, numbness, and little to no swelling. There is usually no bleeding or only minimal bleeding. The fang marks are usually ( . . ) shaped, with a distance of approximately 0.8 to 1.5 centimeters between them. These local symptoms may not be readily noticeable to the patient and should be taken seriously.
Systemic Symptoms
In the early stages, there may be no symptoms, and the individual may appear normal, easily leading to oversight. Within 1 to 4 hours after the bite, symptoms may begin to manifest, including dizziness, blurred vision, sensation of a foreign object in the throat, lethargy, sleepiness, vomiting, and fluctuating bowel movements initially followed by inhibition. The condition rapidly deteriorates, leading to drooping eyelids, inability to open the mouth, tongue paralysis, difficulty swallowing, drooling, hoarseness, difficulty breathing (including clear consciousness but inability to speak, often using gestures to communicate).
In severe cases, respiratory rate slows, breaths become shallow, lips and nail beds turn blue, intercostal muscles become paralyzed, difficulty in diaphragm movement, weakened chest and abdominal breathing, irregular breathing, respiratory arrest, fixed pupils, dilated pupils, loss of light reflex, limb paralysis, loss of muscle strength, gastrointestinal paralysis, and even coma.
When breathing stops abruptly, blood pressure may briefly increase, and heart rate may accelerate. Prompt initiation of artificial respiration and rescue measures offer hope of recovery. Otherwise, death may occur due to respiratory failure followed by circulatory failure. Such patients often retain consciousness after respiratory arrest, so protective medical measures should be taken during rescue efforts.