It’s time for this year’s second installment of student guest posts for my class on infectious causes of chronic disease. First one this year is by Dana Lowry.

Humans have a long history of illness and death from infectious diseases. It wasn’t until the 1790s that we had a solution. Edward Jenner recognized that milkmaids never contracted smallpox but suffered from a more mild disease, cowpox. Jenner took pus from a cowpox lesion on a milkmaid’s hand and placed it in an incision he made in an eight year-old boy’s arm. He then exposed the boy to smallpox; the boy didn’t contract the disease, proving he was immune. Jenner experimented on several other children, including his own 11-month old son, and his theory of passing on immunity proved to be successful. The Latin term for cow is vacca, which is where Jenner coined the term “vaccine”. Jenner’s discovery eventually led to the eradication of smallpox from the U.S. in 1949 and from the world in 1979. For over a century, vaccines were limited to preventing smallpox but as we know today, vaccines prevent a large number of diseases.

Although many developing countries still suffer from the burden of preventable infectious diseases, the U.S. has greatly increased the life expectancy and quality of life through the use of vaccines. In the 1940s, the U.S. recommended vaccines for diphtheria, pertussis and tetanus; polio was added in the 1950s. In the 1970s, measles, mumps and rubella (MMR) were added to list. Today in the U.S., immunizations are recommended for 17 vaccine-preventable diseases during one’s lifetime and more are available for individuals traveling outside of the U.S. Many of these vaccinations are combined so they can prevent multiple diseases from one series of immunizations. The increase in life expectancy in the 20th century is largely attributable to vaccines. For each birth cohort vaccinated, 33,000 lives are saved, 14 million cases of disease are prevented, healthcare costs are reduced by $9.9 billion and $33.4 billion is saved in indirect costs. The Bill Gates Foundation believes that vaccines are one of the most cost-effective investments in global health, saving about 2.5 million lives each year. One child dies every 20 seconds from vaccine-preventable diseases while tens of thousands of other children suffer from severe illnesses and permanently disabling diseases.

Despite the facts, less and less parents are choosing to vaccinate their children today because of fears that vaccines are unsafe. Much of the controversy started with Dr. Andrew Wakefield, a former British surgeon and medical researcher. Wakefield published a paper in 1998 linking the MMR vaccine to autism and bowel disease. Wakefield’s entire study was found to be fraudulent and the infamous paper was retracted in 2010. But, what got more attention than a retracted science paper was Jenny McCarthy sharing her personal life story of how her son got autism from a vaccine on the Oprah Show. Unfortunately, more moms keep up-to-date with Oprah and popular news rather than science and still do not know the truth behind Wakefield’s falsified study; therefore, the autism myth continues.

Furthermore, parents argue “herd immunity”. If your children are effectively vaccinated then why would I have to worry about mine? First, many vaccine-preventable diseases still exist in other countries and can easily be brought into our country; second, some individuals do not build immunity to the disease even after vaccination. The more and more parents that opt out of vaccinations, the less protection their children have from the rest of the “herd”. Additionally, parents argue that their children should contract diseases “naturally” through the environment to build immunity. Parents don’t fully understand the severity of these diseases because many have been virtually eradicated through the successful use of vaccines. Though some crippling effects of polio still linger, it is rare to come across someone wearing braces or using a wheelchair as a result of a polio infection in the U.S. Many vaccine-preventable diseases can cause death during the initial acute illness and if the individual survives, he or she may be left with chronic effects that last a lifetime. Polio can lead to temporary or permanent paralysis, deformities in the hips, ankles and feet; measles, mumps and varicella can all lead to brain damage and mumps is known to cause deafness; hepatitis B can cause permanent liver damage and even liver cancer. The list of damaging effects goes on and on.

In some areas throughout the U.S., as many as 1 in 20 kindergarteners have not been vaccinated. As the antivaccination fad grows in American so do the infectious disease rates. Measles was said to be eliminated from the U.S. in 2000 but an average of about 60 cases of measles occurs each year, typically from traveling. However, in 2011, there were 17 measles outbreaks in U.S. communities and the number of cases jumped to 222. In 2012, the U.S. had one of the largest pertussis outbreaks in nearly 50 years. Nationwide, over 85,000 vaccine-preventable diseases occur each year. I am not arguing that vaccines have no potential side effects and have never caused adverse effects or even death in children. However, I do think vaccines have done considerably more good than harm. So I urge parents, before deciding to withhold your children from vaccinations, look into the facts and make a decision based on science – not popular news. Although outbreaks of disease have been conquered in the past, many vaccine-preventable diseases remain throughout the world and the U.S. is not immune to future outbreaks.