14 Diseases Nearly Eliminated by Vaccines
Human health has improved dramatically since the introduction of vaccines. Before widespread vaccination, diseases like polio, smallpox, rubella, and measles crippled and killed millions of people each year. Now that vaccines for children are common, some of these diseases are virtually non-existent. The World Health Assembly declared smallpox eradicated—eliminated worldwide—in 1980, and the Global Polio Eradication Initiative has managed to drastically decrease polio cases.
Lest we forget why vaccines are important, here’s a look at 14 diseases that once ravaged families and communities.
Before polio vaccines became available in the 1950s, polio outbreaks caused more than 15,000 cases of paralysis in the United States each year—and 2 to 10% of children paralyzed by polio died because the virus affected the muscles necessary to breathe. Many children who survived polio apparently unscathed developed muscle pain, weakness or paralysis as adults, a condition called post-polio syndrome.
Thanks to widespread vaccination, the United States has been polio-free since 1979. Globally, the incidence of polio has decreased 99%, and wild poliovirus only circulates in two countries (Afghanistan and Pakistan).
Smallpox once killed 3 out of every 10 people who contracted it.
In the late 1950s, the World Health Organization initiated a plan to rid the world of smallpox. By then, the United States already had smallpox under control, thanks to vaccination. (According to the U.S. Centers for Disease Control and Prevention (CDC), the last natural outbreak of smallpox in the U.S. occurred in 1949.) The disease was eliminated in North America and Europe in the 1950s and eradicated from South America, Asia, and Africa in the 1970s. No naturally occurring cases of smallpox have occurred globally since 1980.
Tetanus bacteria spores live in soil, dust and manure; when they enter the body (often, via a puncture wound or scrape), spores develop into bacteria (Clostridium tetani), causing infection and producing a toxin. The toxin causes muscle spasms and potentially paralysis. You may have heard of “lockjaw.” That’s a tetanus infection. In some cases, the muscle spasms are so strong that they break bones or interfere with breathing. As many as 1 out of 5 people who get tetanus dies.
Because most American children are vaccinated against tetanus, the U.S. experiences only about 30 cases of tetanus per year; almost all these cases occur in unvaccinated people.
Hepatitis B is a virus that can cause liver cancer and death. Because chronic hepatitis B doesn’t always cause symptoms, a lot of people who have the virus don’t know it and can unwittingly pass the virus on to others via sex or childbirth. Babies who are infected at birth are most likely to develop chronic hepatitis and later liver damage, so public health officials recommend vaccinating children soon after birth.
Hepatitis A is another virus that can cause liver failure and death. Before the vaccine became available in the U.S. (in 1995), the country typically had about 30,000 cases of hepatitis A per year. Now, the number of hepatitis cases in the U.S. is down 95%.
Because hepatitis A is still common in many parts of the world (and spread via contaminated food and water, or personal contact with an infected person), the CDC recommends routine vaccination of children. Adults who have not received a hepatitis A vaccine may need one prior to international travel.
During the United States’ last major rubella outbreak (1964-1965), an estimated 12.5 million people got rubella, 11,000 pregnant women lost their babies to rubella-related miscarriages, 2,100 newborns died, and 20,000 babies were born with congenital rubella syndrome, a condition that can cause deafness, brain damage, and heart defects, according to the CDC.
The U.S. initiated a rubella vaccination program in 1969, and now, fewer than 10 cases of rubella are reported in the U.S. each year. Since 2012, all U.S. rubella cases have been contracted overseas.
Haemophilus influenzae type b (Hib) bacteria can damage the immune system and cause brain damage, hearing loss, and death. (Despite the name, Hib does not cause the flu, which is caused by the influenza virus.) Before widespread vaccination, more than 20,000 Hib cases were reported in the U.S. each year; about 1,000 children died annually of Hib infection and 6,000 experienced deafness, seizures, intellectual disability, or brain damage.
Since Hib vaccines were introduced in the late 1980s, Hib cases have dropped by more than 99%, according to the CDC.
In 1978, the CDC set a goal to eliminate measles from the United States. The measles vaccine, introduced in 1963, was already having a significant impact, and widespread use of the MMR vaccine (a single shot that includes measles, mumps, and rubella vaccines) helped drive numbers even lower. In 2000, the CDC declared measles “eliminated” from the U.S., as there’d been no continuous disease transmission for more than a year.
Sadly, there have been measles outbreaks since then, as vaccination rates in some communities around the country are not high enough to maintain herd immunity.
Before pertussis vaccines were recommended for all infants, whooping cough was a common (and scary) childhood disease: About 8,000 people in the U.S. died annually from whooping cough—most of them infants.
Now, fewer than 20 Americans die each year of whooping cough. Sadly, some babies—many of them younger than 2 months old, the age at which pertussis vaccination begins—still die of pertussis. Widespread pertussis vaccination is necessary to create herd immunity and protect very young babies.
Streptococcus pneumoniae bacteria can cause ear infections, sinus infections, pneumonia, and meningitis (an infection of the lining of the brain and spinal cord). Many people recover from infection without any lingering problems, but some people—particularly children younger than age 2—get seriously ill. Pneumococcal disease can cause deafness, brain damage, loss of arms or legs, and death. About 1 out of 15 children who contract pneumococcal meningitis dies.
Because the bacterium that causes pneumococcal disease has developed resistance to some antibiotics, prevention via vaccination is key to preventing disability and death.
Rotavirus can cause severe diarrhea and vomiting, particularly in young children. And because young children are so much smaller than adults, they can dehydrate much more quickly than adults, which means that children who get rotavirus are much more prone to dehydration and hospitalization than adults.
It’s next to impossible to protect children from exposure to rotavirus, as the virus is shed in stool (poop) and can live on surfaces for several days. Vaccination can protect children from rotavirus infection.
Before the chickenpox vaccine was approved and widely available, approximately 4 million Americans got chickenpox each year, more than 10,500 were hospitalized and 100 to 150 people died. Since the varicella (chickenpox) vaccine was added to the childhood immunization schedule in 1995, chickenpox cases, hospitalizations, and deaths have declined more than 90%.
As many as 1 out of 5 children younger than age 5 who contract diphtheria die. In 1921, before widespread vaccination, the U.S. recorded 206,000 cases of diphtheria, resulting in 15,520 deaths. Decades of vaccination have virtually eliminated diphtheria in the U.S. Between 2004 to 2008, no cases were recorded in the U.S. Over the past decade, the CDC has noted fewer than five cases in the United States.
Before the mumps vaccine was introduced in 1967, mumps was one of the most common causes of deafness and meningitis (an infection of the lining around the brain and spinal cord that can lead to encephalitis, or brain swelling). After the vaccine was added to the childhood vaccination schedule, cases of mumps dropped 99%; now, only a few hundred people contract the disease each year. That number would likely be even lower if vaccination numbers were higher.
Vaccination is not just for babies and children. Adults are also eligible to receive vaccines, including booster shots of vaccines received as a child, such as tetanus. Learn more about vaccines adults should have and the immunization schedule for children.