Christina Hermos, MD'03, MMSC
Photo: Brian Goodchild
Christina Hermos of MMSC, MD'03, was a fellowship 20 years ago and has not seen any measles cases. And it was a rare case involving children arriving from overseas.
Since the measles vaccine emerged in 1963, the infection has dipped to the point where disease was declared in 2000 in the United States.
However, since then, measles outbreaks have been occurring and have spread rapidly among people who have not been vaccinated.
Why are measles so concerned now?
“Measles is a respiratory virus. says Dr. Hermos, an associate professor of pediatrics and director of the Department of Pediatric Sexually Transmitted Diseases at UMass Chan Medical School. “If the unvaccinated population is exposed to someone with measles or is exposed to someone with measles, there is a 90% chance that a susceptible person will be infected.”
“Almost everyone” got infected before the measles vaccine, Elmos said. Many children became very ill, even if only a small percentage had complications. “The complications were very severe, including pneumonia, ruptured eardrums, permanent hearing loss in the child, and a terrible ear infection that includes things that really scary like brain inflammation. [encephalitis] And death. ”
As of early March, CDC reported In 2025, there were over 220 measles cases in the United States, and over 200 EXs have been confirmed to occur in West Texas and nearby New Mexico. Most of the infected people were not vaccinated. Two 6-year-old unvaccinated child and an adult have passed away.
Hermos explained what people need to know about the measles vaccine to keep them safe from this highly contagious disease.
How can you know that measles vaccines are safe?
All drug therapies, including vaccines, will go through phase I, phase II and phase III clinical trials before approval, Hermos said. After preclinical trials, the Phase I trial tests vaccines in a small group of volunteers, assesses safety and identifies side effects. Phase II trials will be conducted in a larger group to further assess safety and efficacy. The Phase III trial involves over 1,000 people (over 1,000) and compares efficacy with standard treatments while further monitoring safety.
After approval for the general population, the drug continues to be studied. The adverse event reporting system provides real-time safety information.
“Vaccinations are more researched than any other approved drug because they are given more widely,” Hermos said. “Because measles vaccines are being used, they've been studied more than statins used to lower cholesterol, for example.”
What is the schedule for giving the measles vaccine?
In 1971, measles vaccine was combined with the mumps and rubella vaccines to form the MMR vaccine. Children receive MMR doses once at one year old and once at around four years of age before entering kindergarten. Some parents have expressed concern about young children who have received several vaccines in a short time.
“The schedule was developed based on the mechanisms that are optimal for host immunity,” Hermos said. “We know how our immune system responds, and we've studied extensively the schedule and selected the best one when we were given a vaccine along with a previously approved vaccine.”
For example, a two-month-old child can get up to eight vaccines at the time of his visit, based on CDC guidelines. “People talk about 'overloading' a child's immune system,” Elmos said.
Why do some people hesitate to vaccinate their children?
Hermos said people might avoid vaccines for a variety of reasons. While mainstream religions do not oppose vaccination, some religious groups avoid modern medicine or generally engage in the health care system. The Texas outbreak is linked to the Mennonite community, where there are high religious exemption rates for vaccination. The Orthodox Jewish community in New York has seen measles outbreaks.
Certain immigrant communities are also being targeted by people who oppose the vaccine. And there is a pocket of people who embrace alternative care and are sometimes promoted through social media.
“Conversations need assessments and you need to listen to where your family is from,” Elmos said. “My pediatric primary care colleague and I tell them that the vaccine is safe, they have been extensively researched and preventing fatal diseases. Then we assess what their fear is.”
The infamous case of causing widespread fear is that it has since been re-retrieved and unreliable since its 1998 article by Andrew Wakefield published in the journal. Rancetfraudulently linked the MMR vaccine to autism.
“We were able to talk about 16 studies that disprove the vaccine's connection,” Hermos said. She refers to someone who the researcher saw a young sibling in a child with autism because of the genetic component. In families who chose not to give their siblings the MMR vaccine, they saw a higher rate of autism than those who chose to receive the vaccine.
“We've been working hard to get the better of our customers,” said Hermos. “MMR is one of the most studied and safest interventions on the planet. I want to remind people what terrible measles is. If it doesn't kill it, it can certainly be permanently injured and cause developmental delays and hearing loss. It's incredibly contagious. The measles vaccine is nearly 100% effective.”
Science for Living features the expert perspective at UMass Chan Medical School on the research behind the Health News headline. If you have an idea for a topic you want to explore, please send it to [email protected].
