What Would Happen If We Stopped Vaccinations?

In the U.S., vaccination programs have eliminated or significantly reduced many vaccine-preventable diseases. However, these diseases still exist and can once again become common—and deadly—if vaccination coverage does not continue at high levels.

On this page (Figures and Statistics Updated 2003):

• Introduction
• Measles
• Polio
• Type b (Hib) Meningitis
• Hepatitis B
• Pertussis (Whooping Cough)
• Pneumococcal
• Rubella (German Measles)
• Varicella (Chickenpox)
• Diphtheria
• Tetanus (Lockjaw)
• Mumps

Introduction

In the U.S., vaccines have reduced or eliminated many infectious diseases that once routinely killed or harmed many infants, children, and adults. However, the viruses and bacteria that cause vaccine-preventable disease and death still exist and can be passed on to people who are not protected by vaccines. Vaccine-preventable diseases have many social and economic costs: sick children miss school and can cause parents to lose time from work. These diseases also result in doctor's visits, hospitalizations, and even premature deaths.

Polio

Stopping vaccination against polio will leave people susceptible to infection with the polio virus. Polio virus causes acute paralysis that can lead to permanent physical disability and even death. Before polio vaccine was available, 13,000 to 20,000 cases of paralytic polio were reported each year in the United States. These annual epidemics of polio often left thousands of victims--mostly children--in braces, crutches, wheelchairs, and iron lungs. The effects were life-long. UPDATED April 2007

In 1988 the World Health Assembly unanimously agreed to eradicate polio worldwide. As a result of global polio eradication efforts, the number of cases reported globally has decreased from more than 350,000 cases in 125 countries in 1988 to 2,000 cases of polio in 17 countries in 2006, and only four countries remain endemic (Afghanistan, India, Nigeria, Pakistan). To date polio has been eliminated from the Western hemisphere, and the European and Western Pacific regions. Stopping vaccination before eradication is achieved would result in a resurgence of the disease in the United States and worldwide. UPDATED April 2007

Measles

Before measles immunization was available, nearly everyone in the U.S. got measles. An average of 450 measles-associated deaths were reported each year between 1953 and 1963.

In the U.S., up to 20 percent of persons with measles are hospitalized. Seventeen percent of measles cases have had one or more complications, such as ear infections, pneumonia, or diarrhea. Pneumonia is present in about six percent of cases and accounts for most of the measles deaths. Although less common, some persons with measles develop encephalitis (swelling of the lining of the brain), resulting in brain damage. 

As many as three of every 1,000 persons with measles will die in the U.S. In the developing world, the rate is much higher, with death occurring in about one of every 100 persons with measles.

Measles is one of the most infectious diseases in the world and is frequently imported into the U.S. In the period 1997-2000, most cases were associated with international visitors or U.S. residents who were exposed to the measles virus while traveling abroad. More than 90 percent of people who are not immune will get measles if they are exposed to the virus.

According to the World Health Organization (WHO), nearly 900,000 measles-related deaths occurred among persons in developing countries in 1999. In populations that are not immune to measles, measles spreads rapidly. If vaccinations were stopped, each year about 2.7 million measles deaths worldwide could be expected.

In the U.S., widespread use of measles vaccine has led to a greater than 99 percent reduction in measles compared with the pre-vaccine era. If we stopped immunization, measles would increase to pre-vaccine levels.

Haemophilus Influenzae Type b (Hib) Meningitis

Before Hib vaccine became available, Hib was the most common cause of bacterial meningitis in U.S. infants and children. Before the vaccine was developed, there were approximately 20,000 invasive Hib cases annually. Approximately two-thirds of the 20,000 cases were meningitis, and one-third were other life-threatening invasive Hib diseases such as bacteria in the blood, pneumonia, or inflammation of the epiglottis. About one of every 200 U.S. children under 5 years of age got an invasive Hib disease. Hib meningitis once killed 600 children each year and left many survivors with deafness, seizures, or mental retardation.

Since introduction of conjugate Hib vaccine in December 1987, the incidence of Hib has declined by 98 percent. From 1994-1998, fewer than 10 fatal cases of invasive Hib disease were reported each year.