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Vaccinations Safe, Avoiding Them Can Be Deadly

flu shot
A nurse gives a shot to a wary but brave boy. Photos: Public Domain U.S. Government/CDC

One hundred years ago influenza spread across the world and killed 20 to 40 million people. The disease killed more in one year than bubonic plague did in four years during the 14th century. The Spanish flu pandemic began in 1918 and started to decline in 1919. It has been called the most devastating epidemic in world history. And in terms of popular culture, Spanish flu provided a plot twist for the PBS drama, “Downton Abbey”, when one of the characters, Lavinia Swire, succumbed to the disease.

Spanish flu

One in 67 American soldiers died of Spanish flu during the pandemic, leading to extensive U.S. flu vaccine research. In September 1918, Spanish flu began to spread rapidly among soldiers at Camp Lee, now called Fort Lee, in Petersburg.

The first flu vaccine was tested on soldiers and college students before being approved for military use in 1945 and for civilians in 1946. The world’s first vaccine was developed in 1796 by English physician Edward Jenner to prevent smallpox. Since then, the acceptance and practice of vaccinating has been varied and hotly debated.

Christy Gray

Christy Gray deals regularly with the ever-changing public attitudes about vaccinations. She is the Director of the Immunization Division in the Virginia Department of Health. “Inoculation enables the body to create antibodies without the risk of being sick,” she explained. Antibodies are proteins made by the body’s immune system when it spots a substance, such as a bacterium or virus, that it doesn’t recognize. The antibodies attach to the substance, called an antigen, to help counter effects it might have on the body.

The ultimate goal of a vaccine is to create memory cells to help the body recognize the antigen, if it ever encounters it again, and generate a stronger and quicker response, Gray said. Memory cells, like all cells in the body, eventually die. That’s why booster shots are given. Gray gave the example of the tetanus booster, which must be repeated every 10 years. “Tetanus is all around us,” she said, so it is critical that this shot be up-to-date. Also called lockjaw, tetanus is caused by bacteria in soil, dust and feces. Ten percent of those who develop tetanus die.

Gray, like all health professionals, becomes concerned when a vaccine works so well that people don’t remember the disease it prevents, or young people have never heard of it. One example is polio, a crippling, incurable and sometimes fatal disease, which killed more than half a million worldwide each year when it peaked in the 1940s and ‘50s.


Jonas Salk developed the first polio vaccine, which was approved in 1955 and was replaced by Albert Sabin’s oral vaccine approved in 1961. Thanks to these vaccines the World Health Organization (WHO) declared in 1994 that the polio virus had been eradicated in the Western Hemisphere. But polio still exists in Afghanistan, Pakistan and Nigeria and could spread easily, according to WHO. Even if polio made a comeback, it would be less transmittable in a well-vaccinated population, Gray said.

The greater the number of people who are vaccinated for a particular disease, the greater the chance of avoiding an epidemic. This is called herd immunity, she said, and is crucial to help protect those who can’t be vaccinated, such as small children, those who are ill or have immune system problems.

WHO declared smallpox eradicated worldwide in 1980 so the vaccine is not given regularly. However, U.S. service members receive smallpox shots because Pentagon officials believe biological weapons may be used in the next major combat, Gray said.

The majority of people in the U.S. have received recommended vaccinations, although fewer are inoculated against flu, according to Gray. Some simply say they haven’t gotten around to it, while others point to one of a host of vaccine myths. One myth often cited is that the shots cause autism. This myth developed from a 1987 study of 12 children, Gray said. The study has been debunked as bad science and fraudulent, and it cost the doctor who conducted it his medical license. Gray also pointed out that autism symptoms usually become apparent around the time children typically receive immunizations before entering school. This adds to the belief of a connection between the two events.

Another of the many myths about immunizations is that an infant’s immune system can’t handle as many shots as are typically given. Actually, a baby’s immune system is very strong and has the capacity to handle many more inoculations, Gray said.

For anyone interested in learning more about the Spanish flu pandemic and the history of medical education, Gray recommends the book, “The Great Influenza” by John Barry.