The document summarizes information about Newcastle disease virus (NDV), including that it is caused by a single-stranded RNA virus from the Avulavirus genus. NDV strains range from lentogenic to velogenic (strongest). The virus is transmitted through contact with feces or other excretions from infected birds and can spread through contaminated materials. Newcastle disease affects many domestic and wild avian species and while it poses little risk to humans, it can cause conjunctivitis or flu-like symptoms in those exposed. Clinical symptoms vary depending on virus strain, health, age and species but include respiratory and nervous signs.