They also bump off one another and rub material off, which is called abrasion. These are all types of erosion. Aeolian erosion makes what we call stone pavement, which is when all the loose stuff on top blows away and you are left with a hard surface. This is kind of like pavement.
Hepatitis A vaccine is an inactivated (killed) vaccine. You will need 2 doses for long-lasting protection. These doses should be given at least 6 months apart. Children are routinely vaccinated between their first and second birthdays (12 through 23 months of age).
Do you need viral hepatitis vaccines? Hepatitis A and B: Diseases of the Liver. Hepatitis is an inflammation of the liver, most often caused by a viral infection. There are three common types of hepatitis caused by viruses: hepatitis A, hepatitis B, and hepatitis C. Vaccines have been developed that protect people from contracting hepatitis A and B. There is no vaccine for hepatitis C.