Vaccination is associated with a nearly halving (40 percent drop) in the risk of Alzheimer’s disease over four years.

Coronaviruses and how the SARS-CoV-2 strain causes Covid-19. Learn about the evolution of coronaviruses and your risk for covid-19

Hepatitis is an inflammation of the liver. Viruses cause most cases of hepatitis. The type of hepatitis is named for the virus that causes it; hepatitis A, hepatitis B, hepatitis C, hepatitis D and hepatitis E.

Hepatitis is an inflammation of the liver. Viruses cause most cases of hepatitis. The type of hepatitis is named for the virus that causes it; hepatitis A, hepatitis B, hepatitis C, hepatitis D and hepatitis E.