From the vaccination's introduction of smallpox vaccine in the 19th century to the mass availability of influenza shots, vaccines have helped millions of people develop immunity to some of the world's deadly diseases.
Thanks to vaccines, many infectious diseases – such as smallpox and polio – no longer exist outside laboratories in the United States. Their enduring elimination has encouraged researchers to work to develop new forms of immunizations that could help people avoid other life-changing diseases.
Here are six one-time disorders that you no longer have to worry about thanks to vaccines.
Smallpox is used to wipe out the population of thousands.
Smallpox is caused by the variola virus and it can easily spread through the air. The disease causes a spotty rash around infected people's faces and bodies that become pustules that are pushed over. Internally, the virus attacks the immune system and causes rapid death.
When European colonies brought cups to America in the 1
In 1796, Doctor Edward Jenner discovered that people could become immune to smallpox if they were given an injection of a similar, less invasive strain of the virus. Jenner's experiments led to the development of the world's first vaccine.
During the next century, vaccinations became routine practice in developed countries.
In 1972, the United States declared that heck was exterminated. Less than a decade later, the World Health Organization announced that cups were the first disease ever to be eradicated from the world. It is the only disease recognized as 100 percent eliminated worldwide.
Polio leaves survivors with lifelong capabilities.
Polio is a viral infection that lives in a person's throat and intestine. One in four people who catch the disease develops flu-like symptoms that go away, but a smaller percentage suffer severe effects, including paralysis and respiratory failure.
Some infected children would spend weeks inside giant machines called iron lungs, as polio made them incapable of breathing alone. According to NPR, 3,000 American children died from polio alone in 1952.
Polio deaths were so common that companies sold polio insurance to newborn parents.
Poliovirus used to spread rapidly among younger populations because it was transmitted orally. This meant that it was easily transferred to places like public swimming pools and day centers.
But when a vaccine was introduced in 1955, the polio frequencies dropped rapidly. In 1979, the disease was considered eliminated from the United States. The last reported case of polio in the US was in the early 1990s, and the patient contracted the disease abroad.
Today, the CDC recommends that children in the United States receive four vaccines for lifelong protection against polio.
According to the World Health Organization, only three countries have active cases of polio this year: Nigeria, Pakistan and Afghanistan.
Diphtheria, a contagious bacterial infection, spread in the early 20th century.
Diphtheria infections hit more than 200,000 people in 1921 and caused about 15,520 deaths this year, according to the CDC.
Diphtheria initially causes infected people to develop a sore throat, weakness and swollen glands. But then a gray-colored mucus begins to cover the back or neck. If the bacteria spend enough time in the bloodstream, the infection can produce toxins that cause permanent nerve damage and heart failure.
The disease spreads when an infected person sneezes, coughs or leaves saliva drops on surfaces or objects. For this reason, people living near, especially in dense cities, were highly susceptible to the disease in the early 1900s.
The diphtheria vaccine was introduced in the 1920s, so natural outbreaks have not been a problem for nearly a century in the United States. Less than five people across the country caught the disease over the last decade, according to the CDC. However, the disease remains common in some developing countries where people do not have access to vaccines.
The CDC recommends that children receive four doses of the diphtheria vaccine followed by booster shots every 10 years to ensure full protection. [19659005Dampspring-child-dilatable-painful-soft-faced
Steam is a respiratory disease caused by paramyxovirus. Like many other viruses, it is spread through contact with saliva. Before the occurrence of the hop vaccine, about 186,000 people in the United States contracted with the virus each year.
A person who catches hops develops painful, swollen salivary glands. Swelling in the jaw area makes it difficult to eat, which in turn makes the patients feel even weaker.
Hops in general are not so deadly, but some patients suffer from lifelong complications such as hearing loss. Ca. 20 percent to 30 percent of the young men contracting the disease run the risk of developing swollen testicles, leading to impaired sensitivity and fertility problems.
Dump cases in the US fell by 99 percent after vaccination introduction in 1967, and there are now only a few hundred cases per year.
Measles causes rash, high fever and severe long-term complications.
Measles (also known as rubeola) attack the respiratory system and other organs. A person with the virus develops flu-like symptoms such as fever and runny nose along with a raised red rash throughout the body.
If the infection is severe, it can cause serious complications such as blindness, brain damage and even death.
An estimated 3 million people contracted the disease each year at the end of the 1950s before the vaccine was available. Of the total, about 48,000 people were hospitalized due to complications and about 400 to 500 people died of it annually.
Measles is highly contagious: It can be transmitted when someone breathes in the same air or touches the same surface as an infected person.
The disease can remain in a room for several hours after an ill patient has left. Because it may take a week or two for the full set of symptoms to develop, many people unconsciously transmit.
CDC-reported measles were eliminated from the United States in the year 2000. Despite recent outbreaks, measles are completely prevented thanks to the two-dose MMR vaccine which also immunizes children against skin and rubella.
Rubella leads to brain damage and birth defects in infants.
Symptoms of rubella (also called German measles) are similar to those of measles, although milder. People who contract rubella usually develop a red rash, pink eye and low-quality fever, although up to 50 percent of the infected people do not experience any symptoms.
In the year 1964, nearly 12.5 million people in the United States contracted illness. This year, almost 11,000 women were affected by miscarriages or stillbirths associated with rubella virus. Children of infected mothers were born with cataracts, hearing impairment, developmental delays and heart failure.
Vaccinations for rubella became available at the end of the 1960s. The New York Times reported in 2015 that rubella had been removed from the Western Hemisphere.
The World Health Organization aims to eradicate the disease worldwide over the next few years.
This article was originally published by Business Insider.
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