Despite highly effective and easily available vaccines, measles outbreaks have continued to occur in the United States over the past 20 years.
Most recently, there have been eight confirmed cases in Philadelphia since December 2023, all of which occurred among unvaccinated people. In addition, people infected with measles passed through. Washington DC area airports Cases have been confirmed in Delaware, new jersey and State of Washingtonaccording to local reports.
According to incomplete information, there were 41 confirmed cases of measles in 2023. data From the Centers for Disease Control and Prevention (CDC).
Although the number of measles cases in the past few years has not been at record highs, and the number of cases in 2023 is lower than in recent years, the fact that outbreaks are still occurring is a worrying trend for health officials and experts.
Measles has been declared abolished in 2000 — That means the disease is “no longer a constant presence in this country.” However, in recent years, mass infections have occurred due to a decline in routine childhood immunizations and due to travelers bringing measles with them.
“The fact that measles cases are occurring sporadically indicates that some areas of the United States are probably undervaccinated, and we suspect this trend is worsening over the years.” I'm concerned,” Dr. Peter Hotez, professor of pediatrics and molecular virology at Baylor College of Medicine, dean of the National School of Tropical Medicine and co-director of the Texas Children's Hospital Vaccine Development Center, told ABC News. .
Slow vaccination rates
A November report from the CDC found that routine immunization exemptions for U.S. kindergarteners are at an all-time high.
About 93% of kindergarteners received some routine childhood vaccines during the 2022-23 school year, including the measles-mumps-rubella (MMR) vaccine, which protects against measles, according to the CDC report.
This is about the same as previous years, but lower than 94% in the 2020-21 school year and 95% in 2019-20, before the COVID-19 pandemic. The latter rate has been the norm for about a decade.
Hotez said there may be areas in the U.S. with higher rates of vaccination exemptions for both medical and non-medical reasons.
“For example, if we I studied this in 2018If you look at states that allow vaccine exemptions for non-medical reasons, you'll find counties where maybe 10 to 20 percent of children are not vaccinated in childhood, and that's what measles is being exploited for.” Hotez said. 93%, which is not ideal, but probably not enough to stimulate a measles outbreak. ”
about 1 in 5 people In the United States, contracting measles can result in hospitalization. According to the CDC, measles can cause serious health complications, including ear infections, diarrhea, pneumonia, encephalitis (swelling of the brain), and even death, especially in children under 5.
The first measles vaccine was a single-dose vaccine and was introduced in the United States in 1963. in the 10 years before thatresulting in 3 to 4 million infections per year, 48,000 hospitalizations, and 400 to 500 deaths.
CDC It is recommended The first vaccination is given at 12 to 15 months of age, and the second vaccination is given in two doses between 4 and 6 years of age. It is 93% effective after one dose and 97% effective after two doses.
Since then, hospitalizations and deaths have fallen dramatically. According to one report, there were three deaths in the Americas in 2000, but only one in 2022. CDC Report for November 2023.
“We can prevent this and we can stop this. Parents should be scared of measles,” said Dr. Paul Offit, director of the Vaccine Education Center and attending physician in the Division of Infectious Diseases at Children's Hospital of Philadelphia. told ABC News. “They should be scared of this virus, just like my parents were. Here's the difference: [my parents] Nothing could be done about it. ”
“Now we can do something about it, which makes it all the more unconscionable when we see kids coming into our clinic who could have been vaccinated but didn't,” he said. added.
Increase in misinformation about vaccines
Experts say there are several reasons for the decline in vaccination rates. One was a 1998 paper published in The Lancet by Andrew Wakefield that claimed that MMR shots caused autism. The paper has since been found to be false, subsequent research has found no link, and the journal has retracted the paper, but concerns still exist.
During the outbreak in Columbus, Ohio, which lasted from November 2022 to February 2023, public health officials found that many parents of unvaccinated children infected with measles reported that MMR causes autism. He said he chose not to have his child vaccinated against the MMR vaccine because of this misconception.
“Since that Umphrew Wakefield article, people have created significant misinformation from that misinformation and continued disinformation about the MMR vaccine,” Dr. Gregory Poland, director of Mayo Clinic's Vaccine Research Group, told ABC told the news. “He claimed there was a link to autism. Then 24 studies found nothing. None suggested a risk for autism.”
“Once you scare people, it's hard to get rid of the fear, so people started walking away from that vaccine,” Offit added. “So we witnessed the incident again.”
Experts said the coronavirus pandemic has created another problem. First of all, in the early days of the pandemic, people were afraid to go to the doctor's office, which prevented them from going to the hospital. Delay in vaccinations for children.
Subsequently, COVID-19 vaccines became politicized, which may have led to a decline in confidence in vaccination as a whole.
Hotez said there is an “acceleration of anti-vaccine sentiment that we've seen during the COVID-19 pandemic,” adding, “And what we're seeing, beyond the COVID-19 vaccine, is the I think this will also have a ripple effect that will spread to childhood vaccinations.”
Another reason for the drop in vaccination rates, experts say, is that the epidemic is so low due to vaccines that people may have forgotten how serious the disease was before the vaccine came along. That's what it means.
It's not just an American problem Number of measles cases worldwide According to a WHO and CDC report released last year, the number of vaccinations has been on the rise in recent years, increasing by 18% from 2021 to 2022, following a decline in vaccinations over the past few years.
The number of global deaths also increased by 43% compared to the same period, with major outbreaks occurring in a total of 37 countries in 2022, compared to 22 countries in 2021.
Experts said they continue to educate parents about vaccine safety and even advocate starting vaccine education at adolescence.
“This is a dangerous game we're playing, leaving a critical proportion of children unvaccinated,” Offit said. “This is a dangerous and unnecessary game we are playing. This is a safe and effective vaccine. This is a virus that can cause great suffering, hospitalization and even death. Don't mess with it or we'll pay you equal reparations.''There needs to be a bigger price than what we're paying now. ”
