Drop in MMR Vaccination Rates Raises Alarm
Experts are expressing concern about a significant dip in the measles-mumps-rubella (MMR) vaccination rates among children in the US, coinciding with a rise in cases across the nation.
A recent study reveals that in 80% of US counties, the uptake of the vaccine decreased last year. Overall, vaccination rates have declined by about three percent nationwide.
This decline means that only 91% of children are now vaccinated against measles, which falls short of the 95% coverage necessary to prevent outbreaks and related fatalities.
Researchers from Johns Hopkins University have cautioned that continued drops in vaccination could lead to a resurgence of measles, turning it into a frequently occurring illness in the US.
As of last week, more than 1,000 confirmed measles cases and at least three deaths have been reported in the US, marking the first measles-related deaths in over ten years.
Most individuals who contracted the disease, as well as all the deceased, had not received their MMR vaccine, largely due to vaccine hesitancy and misinformation, according to experts.
Without the MMR vaccine—which boasts a 97% effectiveness rate—measles is considered one of the most contagious diseases globally.
Symptoms include small white spots in the mouth, flat red spots on various body parts, intense fever, and ear infections.
Experts suggest children receive two doses of the MMR vaccine: the first between 12-15 months of age and the second between 4-6 years. For infants aged 6-11 months traveling internationally, an early dose is advised. Adults should also verify their immunity to measles.
The study analyzed vaccination data for kindergarteners from the 2017-2018 school year to the 2023-2024 year, covering 2,066 counties in 38 states.
Through various statistical models, researchers discovered that 78% of the counties studied—approximately 1,614—reported declines in MMR vaccination rates.
The average county vaccination rate dropped from 93.92% prior to the COVID-19 pandemic to 91.26% afterward. Notably, only four of the 33 states examined—California, Connecticut, Maine, and New York—reported increases in vaccination rates.
Lauren Gardner, the senior author and director of Johns Hopkins University’s Center for Systems Science and Engineering, remarked that this comprehensive dataset is essential for understanding the nation’s vaccination landscape and its implications for measles spread.
This year has seen one of the highest case counts in over 30 years, excluding 2019, with most infections occurring in unvaccinated children.
If a single person contracts measles, up to 90% of non-immune individuals nearby could also become infected. On average, one measles patient might infect up to 18 others who are unimmunized.
Comparatively, those infected with the original strain of COVID-19 typically spread the virus to around two individuals, though this figure increased with newer variants.
Infection can lead to hospitalization in about one in five cases, with one in 20 children facing the risk of pneumonia. The last significant outbreak in the US occurred in 2019, with 1,274 cases reported.
Before that, the largest outbreak was in 1990, with over 27,000 cases. Currently, affected states include Arizona, California, Florida, Texas, and many others, primarily impacting children under 19 years of age.
Measles was declared eradicated in the US in 2000, a milestone celebrated by the CDC as a major public health success.
