Objective: Child with acute flaccid paralysis secondary to anterior horn cell disease due to viral illness mostly West Nile virus was treated successfully with steroids. Methods: 11 year girl presented with tingling sensation of both upper limb, neck upper chest since 1 month. Weakness of both upper limb right more than left with inability to raise hand overhead and to hold pain while writing. On Examination noted extensor weakness of both upper limbs left more than right distal more than proximal with no muscle wasting with diminished upper limb reflexes. Differentials like non polio like illness, Brachial plexitis, Traumatic neuritis and Guillen Barr Syndrome were considered. Acute flaccid paralysis reporting done. Stool culture was negative. CPK and CSF were normal. CSF cuilure for enterovirus was negative. Panel for West Nile virus could not be sent. CT cervical spine showed linear hypodense areas seen in cord from C4 to C6. MRI spine showed altered signal intensity in cervical cord in region of anterior horn cell disease extending from c4 to c6 vertebral bodies. EMG and NCV showed polyneuropathy involving left upper limb which repeated after one month showed improvement in CMAP amplitude. Results: Received oral steroids for 3 weeks with chest physio and Occupational therapy. Weakness of upper limb of left wrist was significantly improved over 8 weeks. Conclusion: The anterior horn of spinal cord contains motor neurons which primarily affect axial muscles. Can be caused by viruses most likely West Nile Virus, Entero viruses, Epstein Barr, Herpes simplex. An acute flaccid paralysis associated West Nile virus should be suspected in patients from areas where West Nile Virus is being transmitted and who have acute, painless, asymmetric weakness, even if unaccompanied by fever, meningo encephalitis, sensory loss or headache.