The measles and more: Q&A with Yale vaccine expert

A recent measles outbreak has sparked anew a long-simmering debate about the safety of common childhood immunizations. Dr. Marietta Vazquez, associate professor of pediatrics at Yale School of Medicine, offers her take on the controversy.
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(Photo: Jerry Domian)

A recent measles outbreak has sparked anew a long-simmering debate about the safety of common childhood immunizations. YaleNews turned to expert Dr. Marietta Vazquez, associate professor of pediatrics at Yale School of Medicine, for an update and her take on the controversy, which has caused the Centers for Disease Control and Prevention to issue a health advisory to providers, and even President Obama to express his support for vaccines.

What is the cause of the recent measles outbreak?

The United States is currently experiencing a large, multi-state outbreak of measles linked to cases reported at DisneyLand in California. As of last month, 102people from 14 states are reported to have measles. 

The current outbreak likely started from a traveler who became infected overseas with measles, then visited the amusement park while infectious. However, no source has been identified.

Travelers bring measles in the country, where the disease is spread primarily to unvaccinated individuals — either infants too young to receive the MMR (measles-mumps-rubella) vaccine or those who have chosen, or whose parents have chosen, to avoid the vaccine.

Measles is a serious respiratory disease caused by a highly contagious virus. It spreads through the air when an infected individual coughs or sneezes. The infection can also cause serious health complications, such as pneumonia or encephalitis, and even death. Children younger than 5 years of age and adults older than 20 are at high risk of getting a serious case of measles. About 1 in 4 unvaccinated people in the United States who get measles will be hospitalized, and about 1 in 500 may die.

What should healthcare providers and the general public do about measles?

First and foremost providers should ensure that all patients are up to date on the MMR vaccine. Parents should make sure they and their children are up to date on their vaccines. One in 12 children in the United States is not receiving the first dose of MMR vaccine on time, leaving those children susceptible to the disease if exposed. 

Unvaccinated U.S. residents traveling abroad are at risk for measles. Returning U.S. residents and foreign visitors may develop measles and expose unvaccinated and vaccinated people. The majority of importations of measles into the United States come from U.S. residents.

Have you treated children with parents who have worries about vaccines? What are their concerns?

Yes, parents come to me with concerns regarding vaccines. Some of the concerns from parents include the pain of the shots, the number of vaccines given to children under age 2, vaccines causing fevers, and concerns that vaccines may cause autism, or contain mercury.

These concerns can lead parents to decline or delay vaccines for their children.   

How do you respond to their concerns?

I do a couple of things: First, I listen. The only way practitioners can successfully address a question is by listening and really understanding where it’s coming from.

So when a patient says, “I don’t want the vaccines,” I listen and ask questions: “Tell me, what are your concerns? What have you heard? Do you know of somebody who had an adverse reaction to vaccines?” Maybe they saw something on TV, read something on the Internet, or maybe they have a family member with autism. 

Listening is the first step; the next is to not preach or indoctrinate. I give information, and I’ll be very frank with parents. I say, “This is my area of expertise; let me tell you about this vaccine.” I talk about what the vaccines are, what is in the vaccine, what is not in the vaccine, because there are a lot of misconceptions. Some people still think there is mercury in vaccines, but it is only present in the multi-dose flu shot. I also make sure that I talk about the diseases in question because oftentimes parents will say no to the MMR vaccine, but I feel that it is my job as a physician to inform them that there is an outbreak and to talk about what nobody wants to talk about — that children can die from this. And then I ask if they have any questions. I give them literature and time to decide. My goal is to help parents make an informed decision. 

What can happen when some parents decide not to vaccinate their children against diseases such as measles or whooping cough?

If enough children do not get immunized, it can break down community immunity and pose a danger to kids who are either too young to get vaccinated or unable to get vaccinated (e.g., children being treated for cancer), as well as those children for whom the vaccine did not provide immunity (unfortunately, vaccines are not 100% effective).

Immunization of adults, pregnant women, and adolescents is also very important. Moms and dads who get vaccine-preventable diseases can pass them on to their babies and children, who may not be old enough to have gotten all of their vaccines yet. Some diseases, like whooping cough, measles, and flu, can be deadly for babies. Children can get these diseases from the adults who care for them.  

Parents, grandparents, older siblings, and anyone who cares for babies should get their flu and Tdap (tetanus-diptheria-pertussis) vaccines. Parents may need other vaccines as well and should ask their doctor which vaccines are recommended for them.  

Some parents who are wary of vaccines believe that “herd immunity” will protect their child. Is that the case?

Some vaccine-refusing parents believe that vaccine-preventable diseases are not a threat. Herd immunity means enough people in a community are immune to a contagious disease — either through vaccination or prior illness — to make its spread from person to person unlikely. Even people who have not been vaccinated are offered some protection because the disease has little opportunity to spread within the community. 

But when measles gets into communities of unvaccinated people (such as people who refuse vaccines for religious, philosophical, or personal reasons), outbreaks are more likely to occur. These communities make it difficult to control the spread of the disease and make us all vulnerable to having the virus re-establish itself in our country again. 

What are the real risks of vaccination?

Vaccines are safe. For more than 30 years, the United States has had a vaccine safety system in place to ensure that vaccines are as safe as possible. There is no evidence to support a link between the U.S. childhood immunization schedule and autoimmune diseases, asthma, hypersensitivity, seizures, child developmental disorders, learning or developmental disorders, or attention deficit disorders. 

The main risks associated with getting vaccines are side effects, which are almost always mild (redness and swelling at the injection site) and go away within a few days. Serious side effects following vaccination, such as severe allergic reaction, are very rare, and doctors and clinic staff are trained to deal with them. The disease-prevention benefits of getting vaccines are much greater than the possible side effects for almost all children.

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