GENERIC NAME: hepatitis A vaccine. DRUG CLASS AND MECHANISM: Hepatitis A vaccine (Havrix, Vaqta) is used to prevent hepatitis A, a type of liver disease that is caused by the hepatitis A virus (HAV).epatitis A vaccine was approved in 2005. PRESCRIBED FOR: Hepatitis A vaccine is used to prevent hepatitis A. Hepatitis A vaccine can be used in persons 1 year of age and older. Although anyone can be infected with hepatitis A, certain people are at high risk and should be routinely vaccinated.
A deficiency is generally a lack of something. It may also refer to: 1  A deficient number, in mathematics, a number n for which Ï (n n. 2  Angular deficiency, in geometry, the difference between a sum of angles and the corresponding sum in a Euclidean plane.
Lack thereof is a phrase meaning that something that was previously mentioned is either missing or is insufficient. Lack is a noun that means deficient or to be without.. Thereof is an adjective that means referring to the thing just mentioned..