Myelitis is acute, but the retroviruses (such as HIV and HTLV) can cause chronic myelitis. Poliomyelitis, or gray matter myelitis, is usually caused by infection of anterior horn of the spinal cord by the enteroviruses (polioviruses, enteroviruses (EV) 70 and 71, echoviruses, coxsackieviruses A and B) and the flaviviruses (West Nile, Japanese encephalitis, tick-borne encephalitis). On the other hand, transverse myelitis or leukomyelitis, or white matter myelitis, are often caused by the herpesviruses and influenza virus. It can be due to direct viral invasion or via immune mediated mechanisms. Bacterial myelitis includes "Mycoplasma Pneumoniae", which is a common agent for respiratory
Acute flaccid myelitis suggesting that the paralysis "per se" is not directly contagious, but arises as a very rare complication of the common respiratory infection. Cases of similar illnesses have been reported in Canada, northern Europe, and Japan. Acute flaccid myelitis Acute flaccid myelitis (AFM) is a rare but serious neurological illness of sudden onset, usually in children. It presents with localised limb weakness and visible changes on MRI. The cause is not currently agreed upon though many sources point to enterovirus 68 as potentially responsible for the condition. Although the illness is not new, a marked increase in cases has been seen