Study compares non–vaccine-preventable illness in vaccinated, unvaccinated children

A new study found that unvaccinated children suffer more from colds and the flu than their vaccinated peers, with study authors seeking to provide evidence-based data for parents who worry vaccines are too taxing on their child’s immune system.

The study was conducted by Michelle Anderson, DNP, FNP, at an Idaho-based family practice in an attempt to answer questions she was asked by well-meaning parents about the effects of vaccination on their child’s short- and long-term ability to fight off illnesses not targeted by vaccines.

The study found a statistically significant difference in the incidence of ear infections, influenza, and common colds among all 3 groups. The fully vaccinated groups had more ear infections than partially vaccinated or unvaccinated children, while the unvaccinated group had significantly higher rates of influenza and common colds, according to the report.

Altered immune system function is a commonly cited concern by parents weighing the risk versus benefit of childhood vaccines today, according to the study. The researchers sought to determine if, and how, vaccines impacted the incidence of common childhood illnesses.

Vaccines are critical to maintaining public health, and have resulted in the eradication in the United States of many previously fatal diseases, including smallpox. The Healthy People 2020 goal is to achieve vaccination rates of 80% or higher for all US children, but there is still an ongoing trend of parental refusal of childhood vaccines for a host of reasons.

One of the most prevalent reasons for vaccine refusal is concern over the short- and long-term effects on the child’s immune system.

“This perceived uncertainty has led to an ever increasing group of people making alternative choices to the immunization schedule and in some cases choosing to not vaccinate their children at all,” the researchers write in their study. “With this trend we have seen the reoccurrence of what were previously considered eradicated diseases, such as measles.”

Parents want more information about vaccines from unbiased sources, fearing pharmacologic company influence in much of the published data.

“Some parents have unsubstantiated concerns about the effect of multiple immunizations on their children’s immune system,” the report notes. “These parents have concerns that it could make their children more susceptible to childhood illnesses. There is little research about the effect of immunizations on other childhood illnesses.”

About 70% of US children currently receive a full set of vaccinations, which include 25 administrations in the first 18 months of life. The study notes that 25% to 38% of parents are worried about their child’s immune system “being overworked.”

“Parents feel when an immune system is regarded as overworked, susceptibility and subsequent incidence for common illness is believed to rise,” the study points out.

To investigate these concerns, the researchers administered a survey to parents of 111 children aged 1 to 7 years, dividing them into groups by vaccine status-fully vaccinated, partially vaccinated, and unvaccinated.

Across the 111-child cohort, there were several significant observations. In terms of flu occurrence, 47.8% in the unvaccinated group reported the flu compared with 30.4% in the fully vaccinated and 21.7% in the partially vaccinated groups.

Another 40.8% in the unvaccinated group suffered from the common cold, compared with 30.6% in the fully vaccinated group and 28.6% in the partially vaccinated group.

Also, unexpectedly, 50.9% of children in the fully vaccinated group reported ear infections compared with 19.6% in the partially vaccinated group and 29.4% in the unvaccinated group.

These were the only significant differences noted among the 3 groups, and the number of office visits among all children was generally the same.

Anderson says that it’s up to nurse practitioners and frontline caregivers to educate parents on all aspects of vaccination.

“Informing parents of the incidence of common childhood illness between the vaccinating and nonvaccinating groups allows them to make vaccine and care decisions for their children from a position of strength and knowledge,” Anderson says. “This is a trust-building process that the practitioner is perfectly situated to accomplish.”

Anderson says she was surprised at the actual statistical difference in the rates of ear infections related to vaccine status. “There are some confounding variables that may have resulted in this finding such as slight age difference between the 3 groups and the size of the study, but it was quite a significant finding,” she says. “I would welcome someone doing this study with a bigger sample size to see if this holds.”

Despite the findings, Anderson says the study was not meant to impact clinical recommendations for vaccine administration, but rather to offer up information to use in the education process.

“This study was more about evaluating for any likely difference [among] the 3 groups and trust building through education than it was about conforming to guidelines. I don't feel the results of this study alter that thought at this time,” Anderson says, adding that the study supported literature on reasons parents choose alternate vaccine schedules.

“The biggest reason was wanting further ‘nonbiased’ studies to assist them in making their vaccine decisions. My feeling is that you establish trust with a family and understanding for their hesitancy, and then educate based on that with supporting evidence-based studies,” Andersons says. “That will look different for every provider, practice, and state based on implemented guidelines.”

Anderson hopes the study will help practitioners answer questions from parents of patients such as hers who wanted to know how vaccines alter immune function and the child’s ability to fight non–vaccine-preventable illnesses.

“These were educated, well-intentioned parents who wanted straightforward, well-thought-out responses. There was a limitation of evidence-based literature to address these questions so I undertook this study for my doctoral project,” Anderson says. “My hope is that I have helped other providers in their practice who face similar questions.”

Ms Zimlich is a freelance writer in Cleveland, Ohio, contributing regularly to Contemporary Pediatrics, Managed Healthcare Executive, and Medical Economics. She has nothing to disclose in regard to affiliations with or financial interests in any organizations that may have an interest in any part of this article.