Guillain-Barré Syndrome (GBS): This is an autoimmune disorder that often follows a minor infection, leading to rapid-onset muscle weakness and, in severe cases, quadriparesis. The presence of bilateral facial nerve palsy and the need for intubation due to respiratory muscle involvement are consistent with severe GBS. Fever at the onset could be related to the triggering infection.

Botulism: This condition, caused by the toxin from Clostridium botulinum, can lead to descending paralysis starting with cranial nerves (causing bilateral facial weakness) and progressing to more generalized weakness. However, botulism typically does not cause fever.
Myasthenia Gravis (MG) Crisis: MG is an autoimmune disease affecting the neuromuscular junction, leading to fluctuating muscle weakness. A myasthenic crisis can present with severe weakness, including quadriparesis and respiratory failure requiring intubation. Fever might not be a direct symptom but could be present if there's an underlying infection triggering the crisis.
Spinal Cord Injury or Lesion: Trauma, infection (e.g., abscess), or other lesions in the spinal cord could cause quadriparesis. However, bilateral facial nerve palsy would be less common unless the lesion affects the brainstem.

Brainstem Encephalitis: Inflammation of the brainstem can cause a wide range of neurological deficits, including quadriparesis and cranial nerve palsies. Fever would be expected due to the infectious or inflammatory nature of the condition.
Meningitis: Although meningitis typically presents with neck stiffness, headache, and fever, in severe cases, especially with brainstem involvement, it could lead to cranial nerve palsies and weakness. It's crucial not to miss this diagnosis due to its high morbidity and mortality if untreated.
Tetanus: Caused by Clostridium tetani toxin, tetanus can lead to muscle stiffness and spasms, which might resemble quadriparesis. While it typically starts with jaw stiffness (lockjaw), it can progress to involve other muscles. Fever might be present, especially if there's an underlying infection.

Diphtheria: A bacterial infection caused by Corynebacterium diphtheriae, which can lead to a membrane covering the tonsils and throat, and in severe cases, toxins can cause neurological manifestations including cranial nerve palsies and weakness.
Poliomyelitis: Although rare in areas with good vaccination coverage, polio can cause acute flaccid paralysis, which might resemble quadriparesis. Bilateral facial nerve palsy would be unusual but could occur in bulbar polio.
West Nile Virus Neuromuscular Disease: West Nile virus can cause a range of neurological diseases, including meningitis, encephalitis, and acute flaccid paralysis. Fever is a common symptom, and in severe cases, it could lead to quadriparesis and respiratory failure.