An increase in non-medical exemptions for childhood vaccines in certain areas of the United States has created several geographic "hot spots" where children are more vulnerable toaccording to new research. While some children can not be vaccinated completely for medical reasons, others are not vaccinated because of their parents' religious or philosophical beliefs. One important reason behind choosing not to vaccinate children for philosophical reasons is the .
Currently 18 states in the US UU They allow non-medical exemptions of childhood vaccines due to philosophical beliefs.
An analysis published in the journal PLOS Medicine found that since 2009 there has been an increase in the number of children enrolling in kindergarten with a non-medical exemption in 12 of these states.
As a result, researchers identified 15 metropolitan high-immunization exemption groups, where more than 5 percent of all kindergarten children are not vaccinated, which correlated with lower MMR vaccination rates (measles, mumps, and rubella). These "hotspots" include:
- Seattle, WA,
- Spokane, WA
- Portland, OR
- Phoenix, AZ,
- Salt Lake City, UT
- Provo, UT,
- Houston, TX
- Fort Worth, TX
- Plano, TX,
- Austin, TX
- Troy, MI
- Warren, MI
- Detroit, MI
- Kansas City, MO  ] Pittsburgh, PA
In addition, the study identified 10 smaller counties with more than 14 percent of unvaccinated preschool children. These counties are predominantly in Idaho, with others in Wisconsin and Utah.
"Our study of vaccine exemptions finds that although immunization rates at the national level may not have changed much, we may have unmasked a large number of rural and urban areas where the number of children does not receive access to vaccines that save lives, "study author Peter Hotez, a professor at Baylor College of Medicine and co-editor in chief of PLOS Neglected Tropical Diseases, told CBS News. "A lot of this reflects organized and well-funded anti-vaccine activities among 18 US states that allow non-medical exemptions for reasons of personal beliefs."
are not currently widespread in the United States thanks to collective immunity, which means that most people throughout the country have been vaccinated. This ensures that the number of people vulnerable to infection is small and helps protect those who can not be vaccinated by preventing their exposure to the virus in the community.
However, that changes the more people do not get vaccinated.
"As unvaccinated populations increase, especially in cities with greater mobility, the potential for outbreaks of vaccine-preventable diseases grows," Hotez and co-author Melissa Nolan of the University of South Carolina said in a joint statement. "Outbreaks of measles are especially worrisome because measles is highly transmissible and is associated with high morbidity, leading to hospitalization and sometimes permanent neurological injuries or even death."
The authors emphasize that a vaccine coverage of 90 to 95 percent measles children is needed, citing the 2014-15 outbreakthat was associated with low vaccination coverage and led to the prohibition of non-medical exemptions in the state.
"A more stringent legislative action to close [non-medical exemptions from vaccination] should become a higher priority," they conclude.
Researchers say they are working on a second study to assess what populations in the high-vaccine exemption "hotspots" have in common so that they can "better focus on public health education campaigns aimed at increasing acceptance of vaccination by these communities. "
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