john endersThe year 2020 will be remembered for the incredible ground-breaking research leading to vaccines to prevent COVID-19, which may progress to new vaccines that will prevent almost any known viral infection in humans, even though they do not contain any weakened or living virus. The same techniques are likely to be used to prevent presently-untreatable diseases such as herpes, mononucleosis and other infections.

In 1955, the world’s first polio vaccine stopped a polio epidemic that recurred every summer for more than 40 years and killed and paralyzed millions of people. The man mainly responsible for the polio vaccines was John Enders, who shared the 1954 Nobel Prize for developing virus-culturing techniques that opened the door to vaccines for polio, measles, mumps, chicken pox and many other life-threatening viral diseases.

During my pediatric residency in the early 1960s, I would go to weekly grand rounds at Boston Children’s hospital and see John Enders, one of the most famous medical scientists in the world, sit in the back of the room and share his wisdom in just a few words, only after being asked for his opinion. Dr. Enders also was a mentor for my medical school advisor, Joe Melnick, who was in charge of the dead virus Salk vaccine and the weakened virus Sabin vaccine trials that ended the yearly polio epidemics. Enders didn’t even work in a lab until he was thirty and performed most of his major investigative work after age 50, after he started his world-famous laboratory at Boston Children’s Hospital after the end of World War II.

A Late Bloomer
John Franklin Enders was born on February 10, 1897, in West Hartford, Connecticut, into impressive wealth. His grandfather, Thomas Enders, was the first full-time employee of Aetna Insurance and became its president in 1872. His father was chairman of the Hartford National Bank and Trust Company and at his death, he left Enders more than 20 million dollars.  During World War I, Enders dropped out of Yale to join the military and was given the death-defying job of flight instructor for biplanes with two canvas wings. In 1920, he returned to Yale and got his degree. He then bought and sold real estate, and found it terribly boring, so he went to Harvard and received a master’s degree in English and planned to spend the rest of his life teaching. This also bored him, so he changed fields again to pursue a PhD in philology (the study of language in literature).

Fortunately for the rest of the world, friends who were medical students introduced him to Hans Zinsser, a published poet and intellectual who wrote regularly for the Atlantic Monthly and was a concert-quality violinist. Zinsser was a professor of bacteriology and immunology at Harvard and the first person to isolate the typhus bacterium. Enders changed his major to bacteriology and immunology and worked with Zinsser to develop an anti-typhus vaccine. He received his PhD at age 33 in 1930.

Vaccine Advances
In 1938, Zissner and Enders showed that they could weaken the mumps virus by culturing it in chick embryos and then using it to make a vaccine that prevents mumps. Zinsser died of acute leukemia in 1940, but Enders carried on his work at Harvard and in 1947, he became head of the Research Division of Infectious Diseases of Children’s Hospital in Boston. There he developed new methods to culture viruses in test tubes and to find viruses just by looking for the cell damage they caused. In 1949, he worked with Tom Weller and Fred Robbins to culture the polio virus in a test tube. In 1954, all three were awarded the Nobel Prize for the discovery of how to grow polioviruses in test tubes.

In 1952, Jonas Salk used Enders’ techniques to develop a polio vaccine. In 1954, Salk announced on the radio that the polio vaccine trial prevented polio, but failed to mention that it was John Enders’ laboratory discoveries that made the polio vaccine possible. Also in 1954, Enders and Peebles isolated the measles virus and produced a measles vaccine. In 1960, Enders tested the vaccine on 1,500 children in New York City and 4,000 children in Nigeria, and showed that the vaccine prevents measles. This vaccine is estimated to have saved more than 100 million lives.

Death from Heart Failure
On September 8, 1985, while reading T.S. Elliot out loud to his wife and daughter, Enders slumped over and died of heart failure. He was 88 years old. His obituaries do not tell his medical history and I do not know if he had any underlying medical conditions. Today, most people think incorrectly that old age inevitably weakens the heart and that an 88-year-old person who dies of heart failure has died of “natural causes”. The truth is that the vast majority of deaths from heart disease are caused by a person’s lifestyle, not by aging, and lifestyle is a much stronger predictor of heart disease than family history.

Heart disease is the leading cause of death in North America today. Each year in the United States, more than 720,000 people have heart attacks at a cost of $108.9 billion, and more than 600,000 die of heart disease. The heart is like any other muscle. It weakens with aging because it loses muscle fibers. However, if you exercise every day, you can enlarge the remaining muscle fibers and help to keep them strong. The same applies to heart muscle. The heart can be damaged by many factors and avoiding these factors can help to protect you from heart disease.

Risk Factors for Heart Attacks
Anything that weakens your heart increases risk for heart attacks and heart failure.
• high blood pressure
• heart valve problems
• a previous heart attack
• rapid resting heart rate (greater than 70 beats per minute)
• nutritional deficiencies of essential vitamins or minerals, such as thiamin (vitamin B-1)
• certain viral infections
• iron buildup in your heart muscle (hemochromatosis)
• various genetic conditions
• chemotherapy drugs to treat cancer
• radiation to treat cancer, or any radiation at all
• diabetes.
• thyroid disorders.

Lifestyle Habits That Can Cause Heart Damage
• lack of exercise
• smoking
• use of drugs such as cocaine, amphetamines or anabolic steroids
• excess weight
• extreme rapid weight loss
• malnutrition
• excess alcohol
• eating too much red meat, fried foods, or sugar-added foods and drinks.
• not eating lots of vegetables, fruits, nuts, beans and other seeds.

A Message From John Enders’ Life
Some of the world’s greatest men are very humble, sitting in the back of a crowd and speaking little.

John Franklin Enders
February 10, 1897 – September 8, 1985