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5 Questions We Get Asked About Vaccines Answered

Pediatricians at Cook Children’s work to inform vaccine-hesitant parents

Whenever a story is posted on Cook Children’s social media pages, especially Facebook, we expect a certain amount of responses from those who refuse vaccines for their children or who are vaccine-hesitant families or patients.

Regardless of statistics, research or science, some parents will never change their minds.

But for the vaccine-hesitant parents who are truly trying to make the most informed decision for their child, let’s take a look at some of the most commonly asked questions and concerns we read on social.

The responses to these questions are based on extensive research conducted by the Cook Children’s Vaccine Clinical Guideline teams, comprised of primary care and specialists in their field. The team cited 99 different sources during their research and their work was approved by the Cook Children’s Medical Center’s Clinical Excellence Committee.

We hope this helps to answer some of your questions.

1. Do vaccines work?

Immunizations are considered to be one of the greatest accomplishments of modern medicine. Compared to pre-vaccine statistics, we’ve seen a reduction in the number of cases of measles by 99.9%, mumps by 95.9%, pertussis by 92.2% and rubella by 99.9%.

This is important because many vaccine-preventable diseases require high vaccination rates to maintain community immunity. For most of the vaccines that are currently available, there must be a population immunization rate for at least 90% to ensure consistent community immunity and some diseases that are highly contagious, such as pertussis or measles, require population immunization rates of at least 95%.

The maintenance of community immunity protects people who received the vaccine but were unable to generate a lasting immune response to the illness, as well as those individuals who are too young to receive a vaccine or have medical reasons that prevent them from receiving a vaccine.

2. Do vaccines cause autism?

This is a most difficult subject to approach because some parents make the direct link to their child’s autism to the vaccines they received.

Because MMR is one of the vaccines that is given to children between 12-18 months and signs of developmental conditions such as autism develop around the same time, it’s easy to see why families would perceive a cause and effect relationship between the two.

This argument was strengthened when Andrew Wakefield published an article in The Lancet in 1998 that claimed a link between the MMR vaccine and autism. Since his initial article was published, investigations have found that Wakefield’s study was flawed by research misconduct, conflicts of interest and lies. This ultimately led the Lancet to retract his original article. In 2010, Wakefield was barred from practicing medicine in Britain.

Dozens of studies have been conducted to look for any possible link between vaccines and autism and these studies continue to confirm no link exists, and that vaccines are safe and effective.

3. If children receive too many vaccines, can it overload their system?

While the number of vaccines that children are given has increased over time, children are actually being exposed to fewer antigens than they had been previously – thanks in large part to the increased purity of the pertussis vaccine.

Some parents may have concerns that vaccines can overwhelm a child’s immune system, but this simply isn’t true. When a child is born, they leave a relatively sterile environment and within hours their GI tract becomes heavily colonized with bacteria. They begin to produce what’s called a specific secretory IgA against these bacteria within the first weeks of life. A 2002 study, published in Pediatrics, states that an infant has a theoretical capacity for up to 10,000 vaccines at any one time.

Multiple studies have been done that show vaccines do not cause an increased risk of infection for children. One study even found that children who received vaccines had a lower rate of infections from vaccine-related and unrelated pathogens. There is also no evidence to support the idea that vaccines lead to increased risk of SIDS. Research has found that vaccines significantly reduced the risk of SIDS.

Children with severe immunodeficiencies who receive live viral vaccines may be at risk for developing an infection or disseminated disease. The biggest concern would be children with T-cell immune deficiencies receiving live virus vaccines. Fortunately these immune deficiencies are usually diagnosed around 6-8 months well before the first live virus vaccines are scheduled (12 months). 

With all that being said, many children with immunodeficiencies can receive vaccines safely, such as certain children with HIV or certain children with malignancies.

4. Is it really hygiene and better nutrition that caused disease reduction and not vaccines?

Statements like this are commonly found in anti-vaccination literature and it implies that vaccines are ineffective and unnecessary. While better hygiene and nutrition have certainly helped to improve the health of our population, it ignores the dramatic effects of vaccination.

If hygiene and nutrition were responsible for disease reduction, you would expect all disease incidence to decrease at around the same time, but this is not what we have seen. Instead, we have seen a recurrent pattern of disease reduction shortly after a vaccine against that disease has become available.

For example, while there was yearly variation in rates of measles, it wasn’t until a vaccine was released and widely distributed in 1963 that we saw a permanent drop in measles cases. Another example is Haemophilus influenza type b, which remained prevalent until the early 1990s when a vaccine that could be used in infants was developed.

Another way of debunking this myth can be to look at individual countries who saw a decrease in their immunization rates. Great Britain saw a dramatic drop in their immunization rates for pertussis in 1974, which was followed by a pertussis epidemic with more than 100,000 cases and 36 deaths by 1978.

In Japan, a drop in pertussis vaccine rates around that time from 70% to below 40% resulted in an increase of pertussis cases from 393 in 1974, to 13,000 in 1979.

5. If your child is vaccinated, why do you care if my child isn’t?

The increasing prevalence of vaccination acts to prevent the circulation of an infectious organism within the community provides benefit to everyone, even those who aren’t vaccinated. This is referred to as community immunity. Community immunity is an important means of protecting the elderly, the young and those with medical conditions that prevent them from receiving vaccines.

For most of the vaccines that are currently available, there must be a population immunization rate of at least 90% to ensure consistent community immunity and some diseases that are highly contagious, such as pertussis or measles, require population immunizations rates of at least 95%.

The maintenance of community immunity is important to protect those individuals who received the vaccine but were unable to generate a lasting immune response to the illness, as well as those individuals who are too young to receive a vaccine or have medical reasons that prevent them from receiving a vaccine.

More on This Topic:


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