2013 Legislation. Alaska: House Bill 21 - would have allowed for four-day school week pilots. This bill failed. California: Senate Bill 236 - would have allowed certain districts to pilot four day school weeks for high schools. This bill was passed and enacted.
Hepatitis B vaccine is a vaccine for the prevention of hepatitis B, an infection caused by the hepatitis B virus (HBV) . The vaccine contains one of the viral envelope proteins, hepatitis B surface antigen (HBsAg). It is produced by yeast cells, into which the genetic code for HBsAg has been inserted.
A pure polysaccharide vaccine for Haemophilus influenzae type b (Hib) is no longer available in the United States. The immune response to a pure polysaccharide vaccine is typically T-cell independent, which means that these vaccines are able to stimulate B cells without the assistance of T-helper cells.o produce an immune response, live attenuated vaccines. must replicate (grow) in the vaccinated person. A relatively. small dose of virus or bacteria is administered, which. replicates in the body and creates enough of the organism. to stimulate an immune response.