image title

Arizona named an anti-vaccine hot spot

June 18, 2018

ASU College of Health Solutions' Alexandra Bhatti talks about why parents might seek exemption, how states differ and what the risks are to the community

A recent study named Arizona one of several “hot spots” in the nation for higher-than-average rates of nonmedical vaccination exemptions. According to the study, published in the journal PLOS Medicine, Arizona has seen an increase in the number of parents seeking vaccination exemptions for their children for religious or philosophical reasons.

According to the study, for the 2016-17 school year, Maricopa County issued 2,947 nonmedical exemptions, the most of any metropolitan area in the country. The next highest number of nonmedical exemptions — 956 — were issued in Salt Lake County in Utah.

To better understand how vaccination exemptions are granted and what these findings mean for Arizona’s public health, ASU Now spoke with Alexandra Bhatti, faculty associate in Arizona State University’s College of Health Solutions.

Question: How do school vaccination laws vary from state to state? How are exemptions obtained?

Alexandra Bhatti

Answer: Each state establishes laws governing vaccination requirements for child care and schoolchildren. One could say, if you have seen one state’s school vaccination laws, then you have seen one state’s school vaccinations laws. No two are identical. Most states adhere to the Advisory Committee on Immunization Practices for determining age, dosage and types of vaccines required.

State laws include exemptions to school vaccination requirements for religious or philosophical reasons, commonly referred to as “nonmedical exemptions.” While all states allow medical exemptions, fewer allow personal-belief or religious exemptions. The ease in which exemptions may be attained varies from state to state. Some require only parental signature, whereas others require a parent to complete a vaccination education module before obtaining a nonmedical exemption.

In addition to vaccination exemptions, students may still attend school without meeting vaccination requirements through a grace period or provisional enrollment. Provisional-enrollment laws allow students to attend school without complete vaccinations if they can show they are in the process of obtaining them. Grace-period laws allow students to attend school for a defined period of time without having to show that they are in the process of being vaccinated or exempted. In Arizona, however, no grace period is offered and students must show either proof of vaccination or an exemption in order to attend school.

State vaccination laws are important for maintaining high vaccination rates, and in turn, lowering the rates of vaccine-preventable diseases (VPDs). Vaccination requirements that have more conditions for receiving a nonmedical exemption, that require parental documentation of exemption requests and that are implemented with strong enforcement and monitoring may help promote higher rates of vaccination coverage and, in turn, lower rates of VPDs in the community.

Q: What are the risks associated with having a growing number of residents who are not vaccinated?

A: We can expect more outbreaks like the Disneyland measles outbreak in 2014 to 2015.

Before the middle of the last century, diseases like whooping cough, polio, measles, Haemophilus influenzae and rubella struck hundreds of thousands of infants, children and adults in the United States. Thousands died every year from them. As vaccines were developed and became widely used, rates of these diseases declined.

Vaccination is very much a community matter. When someone gets vaccinated, not only are they protecting themselves, but also their community — particularly those who are unable to be vaccinated due to age or health conditions.

Most vaccine-preventable diseases are transmitted person-to-person. In a population where most people are vaccinated, they create — in essence — a buffer, preventing the infected from infecting the vulnerable, unvaccinated population. This is called community immunity. As coverage rates decline, community immunity is further compromised, putting those who are unvaccinated at risk of contracting a disease.

Q: What are some of the reasons a person might seek an exemption?

A: It is important to note that the majority of parents do choose to vaccinate their children. For example, in the 2016-2017 school year, measles, mumps and rubella vaccination rates for kindergarteners in Arizona was 94 percent.

There are many reasons why a parent or guardian might seek a nonmedical vaccination exemption for their child. Some may choose to exempt their child because it conflicts with their religious beliefs. I personally know parents who, in an effort to speed up the school enrollment process, signed an exemption form because it was the quickest way to get their child enrolled. With no grace period in Arizona, it may be that the child is on their way to receiving the required vaccines, or already has them, but the parents don’t have the vaccinations records and need more time to complete the process so they opt for the most convenient choice, that being an exemption.

There are also parents that choose to exempt their child due to concerns over vaccine safety or necessity. There is a lot of information out there about vaccinations and vaccination safety, and not all of it is accurate. Unfortunately for parents, it is sometimes hard to determine what to believe. Fortunately, there are some great resources online:

The contents within this Q&A reflect the opinions of only Alexandra Bhatti and do not represent Arizona State University or the Centers for Disease Control and Prevention. Top photo courtesy of Pixabay.com

Katherine Reedy

Media Relations Officer , Media Relations & Strategic Communications

480-965-3779

 
image title

The force is strong within us: New study explores cell mechanics at work

June 18, 2018

State-of-the-art technology and multiple tools help ASU researchers investigate National Cancer Institute question

It’s remarkable choreography: In each of our bodies, more than 37 trillion cells tightly coordinate with other cells to organize into the numerous tissues and organs that make us tick.

The body's cells are subjected to all sorts of environments and forces over a lifespan, calling for methods to quantify mechanical properties of cells and tissues. 

“A few years ago, the (National Cancer Institute) initiated this challenge within the framework of the Physical Sciences in Oncology (PSOC) Network, and several labs in the U.S. and Europe were invited to participate,” said Arizona State University researcher Robert Ros (pictured above), director of Arizona State University’s Center for Biological Physics and a faculty member in the Department of Physics and the Biodesign Institute’s Center for Single Molecule Biophysics.

Ros is an expert within an emerging science devoted toward a better understanding of the routine mechanical and physical forces cells may be subjected to in the body.

These forces include cells rafting through river-rapid-like currents of circulating blood or mosh-pit clumps of crowded neighbor cells within tissues and organs that all serve to bend, push, compress, shear or deform them.

By applying a total of six different technologies, ASU scientists could bend, push, twist and stretch cells in ways similar to what they may encounter within the body.

And so, an international team made up of researchers from eight different labs got to work, including ASU (Ros and graduate students Jack Staunton and Bryant Doss), Johns Hopkins University, University of Pennsylvania, Tufts University, the University of Illinois at Urbana-Champaign, the National Cancer Institute, the University of Paris-Diderot, and the Technical University of Dresden and Saarland University, both in Germany.

Together, they rolled up their sleeves to better understand the physical forces and how best to optimize available technology. They wanted to compare different common techniques and understand the differences in the results of those techniques.  

The force within us

In the study, the team focused on measuring the stiffness, bending, twisting and viscosity of individual cells — focused on a breast-cancer cell line — using all of the most state-of-the art technology at their disposal. ­

How both healthy and cancerous cells respond to this environment — and whether there are key differences that can be identified for future diagnostic applications — was of keen interest to both the NCI and the physicists taking on the NCI’s challenge.  

“All labs received from NCI the same cells (known as MCF-7 breast-cancer cells), and we agreed on similar conditions for the measurements,” said Ros.

But before making their measurements, they first had to ensure that all the subtle conditions of growing cells in the lab were the same, including temperature, acidity of the solution or how long they had been growing.

“We obtained the measurements from a total of six techniques in eight different laboratories using the same breast cells from the same lot, cultured in the same medium from the same lot, all directly provided by the same tissue-culture cell bank,” said Ros. 

The research team employed different technologies to apply mechanical forces to the cells across a number of scales, from inside a cell to whole cells to a single cell layer. Also important to the team was how fast they could make the measurements, which varied from processing a few cells to more than 2,000 every hour.

More to the surface

Three of these groups, including Ros’, focused on an instrument to make cell mechanical measurements that often represents the eyes of nanotechnology, called atomic force microscopy (AFM).

AFMs are a commercially available tool widely used in nanotechnology, and fairly easy to use.

AFMs are so sensitive, they can see down to the level of individual atoms, and for the study, the mechanical forces within the cell. An AFM probe, which is like a record player arm and a type of cone-shaped needle, can apply a force on the surface of a single cell and measure the deformation.

Ros’ focused on Atomic Force Microscopy (AFM). AFMs are so sensitive, they can see down to the level of individual atoms. 

The probes can be interchanged to measure the cellular forces at different scales.

“Overall, our results highlighted how mechanical properties of cells can vary by orders of magnitude, depending on the length scale at which cell viscoelasticity is probed, from tens of nanometers (e.g., the diameter of an AFM tip) to several micrometers (the size of a whole cell),” said Ros.  

“Our measurement with a nanoscale AFM probe showed that the mechanical properties of cells are heterogeneous and vary considerably at a single cell and from cell to cell,” said Ros. “Together, these results show that the mechanical properties of cells measured by AFM can differ more than tenfold, depending on the measurement parameters and the probed regions of the cells, as well as the dimension of the indenter.”

Going with the flow

By applying a total of six different technologies, they could bend, push, twist and stretch cells in ways similar to what they may encounter within the body.

In addition to ASU’s AFM technology, this also included an alphabet soup of technology: magnetic twisting cytometry (MTC), particle-tracking microrheology (PTM), parallel-plate rheometry (PPR), cell monolayer rheology (CMR) and optical stretching (OS).  

They were particularly encouraged when they saw similar results for each of the different techniques.

In addition, their latest results helped confirm data from previous studies, crossing an important scientific verification step — that the measurements could be duplicated.

Opening new avenues

Moving forward, of interest to Ros’ group is measuring these cellular mechanical forces within 3D cell-culture environments that can better mimic cells within the body.

“With this study, we’ve laid the groundwork that our results are more likely to be due to the differential mechanical responses of cells to the different force profiles produced by these different methods, rather than just random errors,” said Ros.

They will continue to explore different types of cells in different environments to see if there is a mechanical force that can be a new type of cell “signature” that may lead to a brand new type of diagnostic tool.

Top photo: ASU researcher Robert Ros is director of ASU’s Center for Biological Physics and a faculty in the Department of Physics and the Biodesign Institute’s Center for Single Molecule Biophysics. Ros is an expert within an emerging science devoted toward a better understanding of the routine mechanical and physical forces cells may be subjected to in the body. Photo by Biodesign Institute

Joe Caspermeyer

Manager (natural sciences) , Media Relations & Strategic Communications

480-727-4858