The measles outbreak is surging in West Texas, especially in under-vaccinated communities, but it’s not just coverage with the measles vaccine that is lagging behind. The use of other key vaccines in the childhood immunization schedule has decreased too.
With lower vaccination rates, experts worry about what vaccine preventable illnesses we could see next.
Coverage with measles-mumps-rubella (MMR), diphtheria-tetanus-acellular pertussis (DTaP), polio, and varicella, or chickenpox vaccines, all declined in more than 30 states last year compared with the year before.
“We are extremely concerned that all of these vaccine preventable illnesses may potentially be making a comeback … But that is, sadly, what may be a reality for us If we continue on a path of questioning legitimate science,” said Dr. Christina Johns, a pediatric emergency physician at PM Pediatrics in Annapolis, Maryland.
Here are some of the illnesses that could emerge again.
Whooping cough
The percentage of kindergartners who received the DTaP vaccine has steadily declined over the past five years, leaving thousands of children vulnerable. Protection among those who are vaccinated can also fade over time.
Rates of pertussis, better known as whooping cough, declined after widespread vaccine use began in 1948. They started to rise again in the 1980s, largely due to increased surveillance and some waning vaccine immunity, but later decreased during the pandemic, when spread of many infectious diseases slowed due to masking and distancing.
Experts say declining vaccination has now lead to an uptick in cases. Last year, there were more than 35,000 cases of whooping cough in the US, the largest number seen in more than a decade.
Whooping cough, a contagious respiratory illness can develop into a painful, full-body cough. The coughing fits can be severe, often accompanied by a whooping sound when people try to catch their breath. Severe cases can be fatal. Last year 10 people died, including six less than 1 year old.
It most severely affects infants but the DTaP vaccine can prevent nine out of 10 infants from hospitalization. The CDC recommends five DTaP doses before the age of 7, with follow up boosters of Tdap in adolescence and adulthood.
Polio
Polio is a contagious virus that at first may give flu-like symptoms but could in some more serious cases progress to meningitis or even paralysis. The CDC recommends four doses of the inactivated polio vaccine (IPV), which is 99% effective, before the age of 6.
“If you drop immunization rates low enough in various areas, polio could come back,” said Dr. Paul Offit, the director of the Vaccine Education Center at the Philadelphia Children’s Hospital.
Polio cases were once common in the United States and around the world. During one of the most severe outbreaks in 1952, the virus infected 58,000 people in the US, paralyzed more than 21,000 and killed more than 3,100. However, vaccination campaigns cut cases dramatically. The last naturally occurring case of polio in the US was in 1979.
In 2022, a man in Rockland County, New York, developed a paralysis from polio.
“He represented the tip of much bigger iceberg. Only one in 200 people who are infected with polio will be paralyzed by it,” said Offit.
More of the community likely had the virus, experts say. Vaccination rates in Rockland County were only around 60%.
“In that particular man’s ZIP code or area, immunization rates had dropped … that’s why it arose there. So let that happen elsewhere and you could see that happen again,” said Offit.
Fewer vaccinations and more illnesses
If vaccination rates continue to decline, the US can expect to see more cases of pneumococcal disease, Haemophilus influenzae type b, mumps, rubella, diphtheria, hepatitis, and rotavirus, according to Martinello.
Without use of the HPV vaccine, experts warn there could be an increase in HPV associated cancers, like cervical, throat and neck cancer, within the next few decades.
These are all included in the routine childhood vaccine schedule – the one that US Health and Human Services Secretary Robert F. Kennedy Jr. said he plans to investigate.
The childhood immunization schedule is decided by the US Centers for Disease Control and Prevention with input from its outside vaccine advisers. The American Academy of Pediatrics, American Academy of Family Physicians and American College of Obestetricians and Gynecologists also approve the schedule. This informs the best time for children to get vaccinated depending on when they will best be able to build immunity against specific illnesses and when they could become most susceptible to diseases. The vaccines on the schedule undergo studies to make sure they are safe to use with other vaccines in the schedule and safety data is continuously evaluated, according to experts.
“All of these aren’t necessarily benign illnesses,” said Johns. “Everybody seems to think that these are all just mild illnesses that you have to get through. And I think that sadly, because vaccines have been such a victim of their own success, we haven’t seen a lot of these infections … so it’s it can be easy to be tricked into thinking that it’s not a big deal.”
A global view
Some vaccine preventable illnesses still circulate abroad, a problem which could be exacerbated by the Trump administration’s extensive funding cuts from USAID, which supported immunization programs around the world.
“I think we’re very selfish,” said Offit. “We’re just focused on ourselves, as if what happens in the world doesn’t affect us, even if we want to be selfish about it … what happens in other places matters.”
Seeing the toll these illnesses can have on patients, some countries experience less hesitance with vaccination than the US does, according to experts.
“One of the drivers of [vaccination] success in these countries is the acute awareness that parents’ have about the potential devastation these vaccine preventable diseases may have on their children and families,” wrote Martinello.