VCU news

By Anne Dreyfuss and Carissa Etters

As measles outbreaks continue to spread in major U.S. cities such as Las Vegas and Chicago, many are left wondering why the potentially deadly illness has made such a strong comeback in recent months. A highly communicable disease, measles has been mostly preventable since a vaccine was developed more than 50 years ago, but misinformation about dangers of vaccinations has led people around the country to opt out of protecting their children from the risk of contracting it and other preventable diseases such as mumps, rubella and polio.

A new CNN/ORC poll shows that nearly 8 of 10 Americans believe parents should be required to vaccinate their healthy children against preventable diseases such as measles. If the children are not vaccinated, most parents agree the child should not be allowed to attend public school or day care. In Virginia, students or parents can choose not to vaccinate their children based on religious or medical grounds.

We recently spoke with two Virginia Commonwealth University School of Medicine faculty members for clarification on common misunderstandings surrounding vaccines and for information on what Virginians can do to protect themselves.

Sean McKenna, M.D., assistant professor, Department of Pediatrics

What are vaccines?

Vaccines are substances we can introduce into the body to help create an active immune response.  That means that the body’s immune system can recognize the virus or bacteria that the vaccine represents. That recognition allows the body to fight off the virus or bacteria before an infection can take place. Vaccines have therefore allowed patients to achieve immunity without suffering through a potentially dangerous infection.

How do vaccines work?

Vaccine development and production is an incredibly complicated process that includes designing, producing, testing and refining. Most vaccines have been improved over the decades by taking smaller and smaller portions of the virus or bacteria so the body can easily recognize it and build the immunity against it, while avoiding side effects or the risk of an actual infection. Immunity comes from the memory that the body develops thanks to several exposures to the vaccine.

Why do some vaccines have to be done in stages?

Most vaccines are administered in stages or repeatedly to continue to give the body reminders to build immunity ensuring a lifetime of immunity. This is known as a “booster effect” – a boost of protection is provided over and over, so there is time for the body to develop a response and then it’s boosted again.

What are the possible side effects of vaccines?

Side effects vary depending on the patient and the particular vaccine that’s being administered. The most common side effect is just a simple local reaction, or soreness and redness, at the site of the vaccine. Anything we introduce into or onto the body also runs the risk of causing an allergic reaction – just like with food or medicines. There are a lot of ingredients that make up a vaccine, so it’s possible someone could be allergic to one or more of those components. Allergic reactions can include a little itchiness all the way up to a severe reaction.

Typically, vaccines are developed using broken-down particles of a virus or bacteria, but there are some that need to actually have the live virus. Live virus vaccines use a weakened form of that virus, but still live, and have the potential to create more of an immune response like a fever or general achiness. It’s important to note that a fever is a sign the immune system is working properly.

What can happen when you don't vaccinate?

A few things can happen when you don’t vaccinate. Of course you’re exposing yourself to an infection from those viruses or bacteria if you’re not protected against it; as such you’re more likely to get sick. Additionally, when you don’t vaccinate you’re also putting others at risk by compromising what is known as “herd immunity.”

Herd immunity is a passive immunization that benefits everyone through group effort. By immunizing as many members of the group as possible, everyone, even those too young to receive vaccines, is protected because it’s almost impossible for a virus or bacteria to make its way into the group. Therefore, there’s less chance for the illness to spread. Measles are a great example of herd immunity. The reason we haven’t seen many cases of measles (until recently) is because, collectively, the herd was vigilant about vaccinating against measles. However, as the movement developed against vaccination, the herd developed “breaks in the armor” against measles and once a measles case re-entered our community, it was able to spread through all of the unimmunized individuals.  Many find this especially troubling because included in the at-risk group are young infants who don’t yet qualify for the measles vaccine and depend on that herd immunity – especially since measles, like many infections, can be deadly to babies.

Richard Wenzel, M.D., professor and former chairman, Department of Internal Medicine

Why do people choose not to vaccinate their children?

There are a number of reasons. One is that not too many grandparents have reminded people of how bad it was. Some people trivialize what measles can do to you. It’s a really deadly virus. It causes hearing loss and inflammation of the brain. Some people who have it will get pneumonia and some will die. We’ve lost the recognition because it’s been out of our consciousness for so long. The second reason is there are people who have a view that: “It’s my right and I’ll decide for my children. Nobody in government will tell me.” In a sense they abandon any kind of respect for their neighbors with that view. Then there are those who are often liberal people living in well-to-do neighborhoods with a Whole Foods store nearby who exercise a lot and are careful of what they eat. They have a fear or concern of putting a chemical into the arms and muscles of their children. They seem to be interested in health on the one hand, but fail to take a holistic view of the risks they’re putting their children in. The fourth group is people who might be unsophisticated and believe that this vaccine can hurt you. Part of that started a number of years ago in the U.K. when a physician named Andrew Wakefield made an erroneous report [about vaccinations causing autism] that has since been retracted.

Why do vaccination laws vary state by state?

There was a federal law that somehow eroded over time. The vaccination rates in Mississippi where it is a strict law are very high. Something like 98 percent of the population is vaccinated. For measles, if you’re much under 95 percent, like in some areas of California where it might be down to 80 percent, the at-risk children will not be protected. The remaining children will be at risk when measles hits. With polio, you need roughly 70 percent of the population immunized to protect the remaining 30 percent, but it’s much less contagious than measles. For every person that gets measles, 15 people who come in contact and don’t have immunity will become infected. That’s one of the highest secondary attack rates. Mississippi has a state rule that everybody has to be immunized with the exception for medical reasons. For example if you have a disease that impairs your immune system – since the measles vaccine is a live virus vaccine and we never give live vaccines to anybody who is immune suppressed, that’s a good reason not to give the vaccine. But you still need 95 percent immunized to protect the remaining five percent, some of whom are immune suppressed.

Do you believe that vaccinations should be mandated?

I think they should absolutely be mandated with excuses for those who have genuine medical issues such as immune suppression or dangerous reaction to prior vaccine.

Are there any drawbacks to mandating vaccinations?

Compared to the alternative there aren’t. Any vaccine can occasionally have side effects, but there is no data that it causes autism or anything really serious. If you compare the disease to the vaccine, it’s case closed. The safety of the vaccine towers over the dangers of the disease itself.

 

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