Measles cases across the country are hitting a 25-year high, and a rising number of vaccination exemptions have some area experts concerned about what it could mean for local populations.

According to the Centers for Disease Control and Prevention, 981 cases of the disease are confirmed across the country, with cases being confirmed in 24 states, including Texas. As of April 5, at least 15 cases of the measles had been confirmed in Texas, including five in Harris and Montgomery counties, according to the Texas Department of State Health Services.

The disease had been considered eliminated in 2000 after vaccination

programs and improvements in first-dose vaccinations. Locally, vaccination rates in Conroe ISD and some private schools are consistent with maintaining herd immunity among school-age children, but experts said if less than 95% of the population is immune, the disease could pose new risks.

“You can have one person … with measles, and they come into contact with other people that have not been vaccinated, and the infection can spread like wildfire,” said Dr. Brian Reed, a family medicine physician and chairperson of the department of clinical sciences at the University of Houston College of Medicine.

Data from DSHS shows the average percentage of students with a conscientious exemption per district is 1.07%. Locally, CISD has seen an increase from 1.14% in the 2012-13 academic year to 1.82% of students in  2018-19, and some private schools in the area have conscientious exemption rates at high as 15%.

Measles risks

The CDC describes measles as a serious respiratory disease that causes a rash and fever that is highly contagious and, in rare cases, can be lethal. Those most at risk of measles are babies and young children who are unvaccinated. The CDC states measles in children can lead to pneumonia, lifelong brain damage and deafness.

Reed said one person infected with measles can infect between 12 and 18 others.

“Our efforts really need to be focused away from the hospitals and keeping measles out of our communities,” Reed said.

What tends to help keep measles in check, said Dr. Richard Lyn-Cook, a doctor affiliated with the Harris Health System, is having around 95% of the population vaccinated against it.

“A 2017 Baylor [University] report by Dr. [Peter] Hotez suggested that there are quite a few municipalities and counties in Texas that are approaching less than that 95% threshold,” Lyn-Cook said. “Our vaccination rates are still pretty good ... but we still don’t vaccinate kids less than a year old, so that entire population of kids is now vulnerable.”

Having a large percentage of a community vaccinated is known as “herd immunity” or “community immunity.” The practice, according to Chris Van Deusen, the DSHS director of media relations, prevents the spread of the disease through a particular area.

“If almost everybody in, say, a town, are immune to measles, and somebody with the measles shows up, it’s going to stop it,” Van Deusen said. “It’s not going to spread to anybody else, or, it might spread to the one person who wasn’t immunized, maybe because they’re an infant or for some other reason. … But you’re not going to have sort of an ongoing chain of transmission that’s putting more people at risk.”

Herd immunity also helps protect those who cannot get vaccines for medical reasons, such as those with allergic reactions or weakened immune systems and those who are pregnant.

Misti Willingham, the Montgomery County Hospital District public information officer, said measles is an airborne disease, and it spreads quickly, especially to those who are unvaccinated.

“Whenever people make a decision to not have their child vaccinated, it’s not only affecting their child, it’s affecting everyone around them—the people who go to day care with them, the people in their school. It affects our entire community,” Willingham said. “It’s really a public health issue. I’ll tell you a little about how contagious measles is: 90% of people who are unvaccinated and come into contact with an infected person will contract the virus—and it’s airborne.”

Focus on schools

Under Texas law, students are required to be up to date and show evidence of vaccination prior to entry and attendance of a child care facility, public school or private school. Van Deusen said the first state requirements for immunization were passed in 1971 and covered polio, diphtheria, tetanus, measles, rubella and smallpox.

Medical exemptions are granted when a physician submits a statement that the vaccine would be medically harmful or injurious to the health and well-being of the child.

However, state lawmakers made it legal for parents to seek exemptions for their children for reasons of conscience in 2003. Prior to 2003, exemptions were only granted for religious or medical reasons.

“Essentially, a parent can request a form from us that they then complete, have notarized and file with the school,” Van Deusen said. “The law allows parents to get an exemption for philosophical or religious reason. There is also a separate medical exemption.”

Willingham said the number of parents seeking vaccination exemptions for their children has risen since 2013, which affects the percentages needed to maintain herd immunity.

“The more people who are not getting vaccinated, the more people who are going to get the measles and are going to spread it to other people,” Willingham said. “The first dose is 93% effective. The second dose is 97% effective.”

Van Deusen said at the state level, there are not major concerns regarding vaccination rates, as the average runs from 96% to 99%. However, he noted schools and areas with lower vaccination rates are at a greater risk if a vaccine-preventable disease is introduced there.

For the 2018-19 school year, 96.55% of CISD kindergartners were vaccinated for measles, mumps and rubella, although the rate for seventh graders is 99.01%. At some private schools, however, the number is lower. At The Woodlands Christian Academy, for example, the 2018-19 rate drops to 82.93% for seventh-graders.

Local conscientious exemption rates vary. In CISD, the number of students with conscientious exemptions for the 2018-19 school year is 1,113 students, or around 1.82% of the total student population, according to CISD Coordinator of Health Services Barbara Robertson. In 2016-17, 1,030 students had conscientious exemptions.

“The number of students with a conscientious exemption has remained fairly consistent over the past four years,” Robertson said.

Private schools

Among area private schools, conscientious exemptions ranged from no students at St. Anthony of Padua School to 15.51% at Legacy Preparatory Christian Academy. The John Cooper School recorded 1.51% of students requesting conscientious exemptions in 2018-19, while The Woodlands Christian Academy reported 5.2% in 2018-19.

However, Catholic schools such as St. Anthony of Padua follow the Texas Catholic Conference of Bishops Education Department policy which does not allow conscientious exemptions, school officials said.

Other school policies vary. Ann Snyder, head of schools for The Woodlands Methodist School, said the school only allows medical exemptions except in cases in which the health of another household member could be affected.

“Any student exempt from some or all immunization will be excluded from school if a vaccine-preventable disease is present in the school or an outbreak of a vaccine-preventable illness occurs in the community,” said Snyder, who also serves on The Woodlands Township board of directors.

Cook said he would encourage the public to cross-check information they find on various websites with the CDC and the World Health Organization to prevent the spread of misinformation about vaccines.

“It’s important for us to engage in advocacy. It isn’t enough for me just to talk to individual families in the clinic—it helps,” Cook said. “The medical community, physicians, concerned parents, families, legislators—everyone should contact our state legislators and let them know that these initiatives, while they may seem well-intentioned, are actually highly dangerous to public health and people need to speak with the power of the ballot.”

Additional reporting by Kara McIntyre, Jules Rogers and Hannah Zedaker