Complications from the viral infections that cause<unk>  are rare, but require immediate medical treatment if present.<unk>  infections caused by Enterovirus 71 tend to be more severe and are more likely to have neurologic or cardiac complications including death than infections caused by Coxsackievirus A16. Viral or aseptic meningitis can occur with<unk>  in rare cases and is characterized by fever, headache, stiff neck, or back pain. The condition is usually mild and clears without treatment; however, hospitalization for a short time may be needed. Other serious complications of<unk>  include encephalitis (inflammation of the brain), or flaccid paralysis in rare circumstances. Fingernail and toenail loss have been reported in children 4–8 weeks after having<unk> . The relationship between<unk>  and the reported nail loss is unclear; however, it is temporary and nail growth resumes without treatment. Minor complications due to symptoms can occur such as dehydration, due to<unk>  sores causing discomfort with intake of foods and fluid.
Hand, foot, and mouth disease
Cowpox
Progressive vaccinia
Chickenpox
Smallpox
Shingles
Sealpox
Mumps