Varicella zoster virus countries. Varicella vaccination has raised concerns in some that the immunity induced by the vaccine may not be lifelong, possibly leaving adults vulnerable to more severe disease as the immunity from their childhood immunization wanes. Vaccine coverage in the United States in the population recommended for vaccination is approaching 90%, with concomitant reductions in the incidence of varicella cases and hospitalizations and deaths due to VZV. So far, clinical data has proved that the vaccine is effective for over 10 years in preventing varicella infection in healthy individuals and when breakthrough infections do occur, illness is typically mild. In 2007,
Motor neuron disease Motor neuron disease Motor neuron diseases (MNDs) are a group of neurodegenerative disorders that selectively affect motor neurons, the cells which control voluntary muscles of the body. Commonly, the following disorders are counted among motor neuron diseases: The term “motor neuron disease” sometimes refers to ALS, but in this article, the term refers to a group of diseases listed above, which includes ALS. Motor neuron diseases affect both children and adults. While each motor neuron disease affects patients differently, they all cause movement-related symptoms, mainly muscle weakness. Most diseases seem to occur randomly without known causes, but some forms are