These 15 health breakthroughs changed the world

According to a study led by the World Health Organization, vaccines have saved an estimated 154 million lives over the past 50 years with 101 million of those lives being infants.

Vaccines have been around for more than 200 years, with the first successful vaccine being the smallpox vaccination that came in 1796.

Pictured here a young woman receives her smallpox vaccination at a smallpox vaccination clinic in London on Jan. 15, 1962.

Because of anesthesia pain can be controlled during medical procedures and surgery became routine. Pictured here an anesthetist adjusts the gas flow to a patient circa 1955.

Jeremy Farrar, chief scientist at the World Health Organization, spoke with USA TODAY about some of the top medical advancements throughout history.

“The realization that clinical medicine and public health are scientific endeavors,” including the onset of clinical trials, was one of the top medical advancements, Farrar said.

This may not seem obvious today, he noted, but historically that wasn’t always thought to be true.

Farrar gave the example of John Snow, who gathered evidence and created a map that showed a public water pump in London was the source of a cholera outbreak in 1854. It was contaminated by sewage from the River Thames and cesspools, and hundreds of people died who lived near the Broad Street water pump.

A replica of the pump is seen here in a screenshot from Google Maps outside a pub that was named after Snow. Farrar said Snow’s work was the dawn of the scientific age where the evidence was provided through a hypothesis and testing. “Scientific method has transformed the whole of public health and medicine and it’s unthinkable now that we wouldn’t do that,” Farrar said.

Insulin transformed type 1 diabetes from a fatal diagnosis to a medically manageable chronic condition. Insulin therapy helps people with diabetes maintain their blood sugar levels. In 2021, the world celebrated the 100th anniversary of the discovery of insulin.

Pictured here a worker operates the distilling and extraction apparatus at an insulin factory in Bielefeld, Germany, in 1946.

Research that showed the harmful health consequences that smoking could cause, including lung cancer, heart disease and stroke.

Scientific innovations that changed the field of medicine, such as the discovery of penicillin in 1928 that led to treatment and prevention of infections through antibiotics, antiviral drugs and anti-parasitic drugs that exist today. Alexander Fleming, pictured here in 1954, was a Scottish physician-scientist and Nobel laureate best known for his discovery of penicillin.

Occupational health to ensure safe workplaces was another top medical advancement, according to Farrar. “Your workplace is a very important part of your health …and your employer has responsibilities (to keep the work environment safe),” said Farrar, who listed asbestos, pollution and unsafe work practices as health risks to protect employees from.

A group of Women's Auxiliary Air Force (WAAF) officers are photographed undergoing instruction in the use of wearing gas masks during air raid precaution training in 1941 in England.

An undated portrait of French chemist and microbiologist Louis Pasteur, who developed the germ theory of disease in the 1860s. It is the theory that microorganisms can invade the body and cause disease.

Oral Rehydration Therapy, which is consuming a mixture of salt, sugar, and water as a first-line treatment for dehydration due to diarrhea and vomiting that can be caused by the range of conditions including cholera, typhoid, and other causes of diarrhea.

Pictured here a mother sits with her baby as Pakistani children get treated for stomach ailments, diarrhea and dehydration at the Mardan District hospital on May 25, 2009 in Mardan, Pakistan.

Because of antiretroviral drugs, HIV/AIDS went from being a fatal infection to a manageable chronic condition, if people had access to these drugs. They are used to treat and prevent HIV/AIDS.

The U.S. Food and Drug Administration (FDA) has approved more than 30 HIV medicines to treat HIV infection, but the first antiretroviral drug was approved for use in 1987 called zidovudine (AZT).

A cocktail of premixed antiretroviral drugs is pictured here on July 11, 2002, in Miami, Florida.

The human genome project, which was an international collaboration that mapped the entire sequence of human DNA to provide a foundational understanding of human genes and their functions.

“The human genome project transformed how open science through global collaboration can drive advances and how science can be applied to medicine, in terms of genetic diseases, risk factors, and the whole revolution in biomedicine which has led to drug and vaccine discoveries and preventative treatments,” Farrar wrote in an email.

President Bill Clinton (L) is photographed speaking with Dr. Francis Collins (R), the director of National Institutes of Health, who was instrumental in the Human Genome project, prior to announcing the completion of the first survey of the entire Human Genome on June 26, 2000 at the White House.

The creation of national, regional and global public health agencies including the World Health Organization. “We all depend on each other, and that's going to be a crucial underpinning of the future of the world's public health,” Farrar said. World Health Organization (WHO) Director-General

Tedros Adhanom Ghebreyesus is pictured at the WHO headquarters in Geneva on Oct. 18, 2021.