MAY 24, 2016 7:31 AM PDT

Outbreaks spike when parents say ‘no' to vaccines

An analysis of several studies of measles and pertussis outbreaks in the United States suggests that when parents refuse vaccinations for their children or for themselves, they contribute largely to outbreaks of those diseases.
"Fundamental to the strength and legitimacy of justifications to override parental decisions to refuse a vaccine for their child is a clear demonstration that the risks and harms to the child of remaining unimmunized are substantial," says Saad Omer.
For a new study published in the Journal of the American Medical Association, researchers searched the medical literature for reports of US measles outbreaks that have occurred since measles was declared eliminated in the United States (after January 1, 2000), endemic and epidemic pertussis since the lowest point in US pertussis incidence (after January 1, 1977), and for studies that assessed disease risk in the context of vaccine delay or exemption.

Among 32 reports of pertussis outbreaks, which included 10,609 individuals for whom vaccination status was reported (ages 10 days to 87 years), the five largest statewide epidemics included substantial proportions (24 to 45 percent) of people who were unvaccinated or undervaccinated.

However, several pertussis outbreaks also occurred in highly vaccinated populations, indicating waning immunity. Nine reports (describing 12 outbreaks) provided detailed vaccination data on unimmunized cases; among eight of these outbreaks, 59 to 93 percent of unvaccinated individuals were intentionally unvaccinated.

“This review has broad implications for vaccine practice and policy,” says Saad Omer, professor of global health at Emory University’s Rollins School of Public Health.

“For instance, fundamental to the strength and legitimacy of justifications to override parental decisions to refuse a vaccine for their child is a clear demonstration that the risks and harms to the child of remaining unimmunized are substantial. Similarly, central to any justification to restrict individual freedom by mandating vaccines to prevent harm to others is an understanding of the nature and magnitude of these risks and harms.

“Our report shows that outbreaks of vaccine-preventable diseases in the United States have prompted clinicians, public health officials, and the public to pay greater attention to the growing phenomenon of vaccine refusal and hesitancy. We believe this study will result in an improved understanding of the association between vaccine refusal and the epidemiology of these diseases.”

Source: Emory University

This article was originally published on futurity.org.
About the Author
  • Futurity features the latest discoveries by scientists at top research universities in the US, UK, Canada, Europe, Asia, and Australia. The nonprofit site, which launched in 2009, is supported solely by its university partners (listed below) in an effort to share research news directly with the public.
You May Also Like
OCT 12, 2021
Drug Discovery & Development
Preventing future pandemics - Scientists developing broadly protective vaccines against coronaviruses
OCT 12, 2021
Preventing future pandemics - Scientists developing broadly protective vaccines against coronaviruses
Researchers at Japan’s Osaka University recently developed and tested a novel vaccine that may protect a ...
OCT 26, 2021
Immunology
Two Different Arms, Twice the Cancer-Killing Potential?
OCT 26, 2021
Two Different Arms, Twice the Cancer-Killing Potential?
Our immune system has developed an arsenal of sophisticated molecular weapons to defend us against the continuous barrag ...
NOV 03, 2021
Plants & Animals
A Samoan Plant May Reduce Inflammation as Well as Ibuprofen
NOV 03, 2021
A Samoan Plant May Reduce Inflammation as Well as Ibuprofen
To the people of Samoa, the medicinal qualities of a tree known as matalafi are well known. Now scientists are bringing ...
DEC 11, 2021
Health & Medicine
Third Dose of Pfizer-BioNTech Vaccine Could Reduce Effects of Omicron
DEC 11, 2021
Third Dose of Pfizer-BioNTech Vaccine Could Reduce Effects of Omicron
Many mainstream media sources are reporting on a new press release from Pfizer that suggests that a third dose of the Pf ...
DEC 21, 2021
Immunology
Shark Immune Proteins as Pandemic 'Insurance'?
DEC 21, 2021
Shark Immune Proteins as Pandemic 'Insurance'?
Sharks are incredibly hardy creatures—they've survived in marine ecosystems, often unchallenged predators, for ...
JAN 07, 2022
Cancer
Crossing the Blood-Brain Barrier: Improving Experimental Models to Study Drug Delivery
JAN 07, 2022
Crossing the Blood-Brain Barrier: Improving Experimental Models to Study Drug Delivery
The blood-brain barrier (BBB) describes the complex vasculature network that delivers oxygen and nutrients to the brain. ...
Loading Comments...