Vaccines have been so successful that we don’t see the diseases they prevent every day. As a result, they may not seem as scary as they used to. But, vaccine-preventable diseases still cause a lot of suffering and death worldwide. An infected person can travel to the United States, and we can travel anywhere in the world. There are still documented cases of vaccine-preventable diseases all over the world each year. By immunizing, we can make sure these diseases do not become everyday events again.
Chickenpox was one of the most common childhood diseases. Before the vaccine, there were about 4 million cases a year in the United States. The chickenpox virus usually causes mild illness with a fever and an itchy rash. It also can lead to severe skin infections, scars, and serious problems. About 1 child in 500 who gets chickenpox is hospitalized.
Diphtheria causes a thick covering in the back of the throat that makes it hard to breathe or swallow. About 1 in 10 people with diphtheria die from breathing problems, paralysis, or heart failure. Before the vaccine, about 150,000 people a year got diphtheria in the United States.
Hepatitis A is a serious liver disease that is usually spread by close personal contact or by eating contaminated food or water. Hepatitis A can cause mild, “flu-like” illness, jaundice, and severe stomach pains and diarrhea.
Hepatitis B is another serious liver disease that can cause short-term (acute) illness. Some people develop a long-term (chronic) illness that leads to liver damage, liver cancer, and death. Even though these people may not feel sick, they carry the virus and can infect other people. The virus is spread though contact with blood and other bodily fluids of an infected person. Pregnant women can infect their newborn.
Measles virus causes a rash, cough, runny nose, and fever. It can lead to ear infections, pneumonia, seizures, brain damage, and even death. Measles is so contagious that in 1962, the year before the vaccine, almost 500,000 cases of measles were reported in the United States.