Measles: A Crisis of Herd Immunity
Written by: Melbourne Romney | Edited by: Nathan Hahn
When we think about diseases impacting school children, we mostly think about the common cold, flu, and maybe even strep throat. However, less than 100 years ago, outbreaks of Polio, Chickenpox, Measles, and countless other life-threatening diseases were not uncommon. Polio left 1 in every 200 patients at least partially paralyzed and a further 40 percent of all survivors with Post Polio Syndrome (PPS), demarcated by long-term muscle weakness, chronic fatigue, and joint pain. One of the most contagious of these diseases is Measles. Pre-vaccine, affecting 3-4 million people in the US per year, Measles was a highly contagious disease infecting 9 out of 10 people who are exposed to an infected individual. Although not notably deadly to most of the population, it is a very dangerous disease for children under 5, chiefly through complications like pneumonia (severe swelling and fluid buildup in lungs) and encephalitis (swelling of the brain). Despite its extreme infectivity, with the introduction of the MMR vaccine (measles, mumps, and rubella) in 1963, cases quickly dropped to less than a couple hundred per year. However, with the recent increase in vaccine skepticism, minor outbreaks are beginning to occur in the US. 2019 saw an outbreak starting in New York which led to over 1000 cases, 73 percent of whom were unvaccinated. This trend has continued with almost 300 cases occurring in 2024 and the ongoing outbreak impacting at least 600 people, with numbers quickly rising.
The ongoing outbreak began in late January in a Mennonite community in western Texas, where many children are homeschooled and unvaccinated. This outbreak has since exploded to over 600 cases (as of early April), with the numbers quickly growing. Meghan Messick, the co-owner of Tiny Tots Day Care Center in Lubbock Texas—where 7 children have been confirmed to have contracted measles—describes the horrifying situation on the ground. She describes the attitudes of parents as “muddy water” with some parents angry that the facility is doing too much and isolating infected children, while others are angry the facility is doing too little to prevent infections. Daycares like this are at extreme risk during a measles outbreak, with a very high concentration of very young children (the most at risk for being hospitalized due to measles) many of whom are not fully up to date on their MMR vaccines. Previously, daycare centers like this (as well as schools and any other childcare facilities) would be protected by laws requiring vaccines, however, recent laws allowing for vaccine exemptions for personal belief have become widespread.
When considering that parents are being emboldened to not vaccinate their children due to widespread vaccine skepticism after the COVID-19 pandemic, these laws have created a very dangerous situation for measles and other previously eradicated diseases as we have fallen below the 95% vaccination rate needed for herd immunity. These factors have led to a sharp decrease in vaccination rates in kindergarteners across the country.
These numbers are even lower in certain states, including Idaho at 79.6%, Wisconsin at 84.8%, and Florida at 88.1% (all numbers for percent of kindergarteners who have received two doses of the MMR vaccine). Surprisingly, Texas has a rate of 94.3%, however, Gaines County, which has seen over half of reported cases, sits at a rate of 82%. When considering how quickly the virus has spread and how many have been infected in a single county, it is worrying to consider a whole state with an even lower vaccination rate.
We have seen how a change in vaccination laws has impacted vaccination rates, but how specifically has this sense of vaccine skepticism flourished in many communities? Part of the issue is misinformation, especially spread via social media. However, vaccination has been constantly criticized by a fringe group of anti-vaxxers, so this cannot be the whole picture of why the practice has increased so much during and after COVID. The answer to this question seems to be in the response to the virus which President Trump pushed throughout the pandemic. In March 2020, then-president Trump stated, “Think Easter Sunday, you’ll have packed churches all over our country,” touting that the pandemic would be short and only a small inconvenience. This was completely contrary to the leading public health guidelines at the time and began a long history of republican leaders taking COVID, and vaccination in general, for granted. This was followed by a general distrust in modern medicine, with Trump himself boasting about untested treatments like taking the anti-malaria medication Hydroxychloroquine (which has been possibly linked to deaths during the COVID pandemic due to its cardiovascular risks). This is brought to the modern day with Trump’s section of Robert F. Kennedy Jr. for the Secretary of Health and Human Services. Kenedy was previously the leader of Children’s Health Defense, an anti-vaccination nonprofit, and has a history of extreme vaccine skepticism. If Trump’s vaccine skeptical comments emboldened parents to withhold vaccination, Kenedys appointment as the top health official of the US has lit a bonfire. During the current outbreak, he has already questioned the effectiveness of the MMR vaccine and is preaching “natural remedies” like cod liver oil to treat Measles. This is not only harmful as it will lead to even fewer vaccinations, but his proposed “treatment” has led to liver damage due to vitamin A toxicity in Texas children due to its high concentration in cod liver oil and its extreme toxicity in high doses.
At the current moment, there doesn’t seem to be a respite from our political leaders’ own vaccine skepticism, which leads me to believe that outbreaks like the one we are experiencing now will become more regular and much more severe. This current outbreak has already seen three times as many infections as last year, giving the possibility of future outbreaks affecting thousands of children across America. However, outbreak size heavily depends on its place of origin and the ferocity of the response, but given the current administration, we cannot expect any better than we are seeing now.
Although this data on vaccination rates is extremely concerning, we cannot expect this pattern of outbreaks to continue every year. Introduction of measles from other countries is relatively rare and the conditions for an outbreak are unpredictable. However, if vaccination rates continue to decrease (or simply don’t increase in many locations) we will get further and further from herd immunity, setting the stage for a possibly devastating epidemic that could grow into a national health crisis.
Images Sources:
- Fig. 1: A measles sign is seen at the Texas Tech University Health Sciences Center, Feb. 25, 2025, in Lubbock, Texas. (AP Photo/Julio Cortez, file)
- Fig. 2: https://www.immunize.org/wp-content/uploads/laws/exemptions-ccsch-rqt-map-2024.pdf
- Fig. 3: https://www.nytimes.com/2025/01/13/briefing/childhood-vaccinations-trump.html
- Fig. 4: https://www.cdc.gov/measles/data-research/index.html
Other Sources:
- https://www.forbes.com/sites/joshuacohen/2024/01/07/trump-promoted-hydroxychloroquine-to-treat-covid-19-a-drug-now-linked-to-17000-deaths/
- https://www.nytimes.com/interactive/2025/health/measles-outbreak-map.html
- https://www.nbcnews.com/health/health-news/texas-measles-daycare-outbreak-confirmed-cases-rcna199631
- https://www.cdc.gov/mmwr/volumes/73/wr/mm7341a3.htm
- https://www.cdc.gov/polio/about/index.html
- https://www.cdc.gov/measles/about/index.html
- https://www.cdc.gov/measles/about/history.html
- https://www.nejm.org/doi/full/10.1056/NEJMoa1912514
- https://www.cdc.gov/measles/data-research/index.html
- https://abcnews.go.com/Health/child-measles-dies-texas-hospital-officials/story?id=120539137#:~:text=Measles%20outbreak%20in%20Texas%20shows,have%20confirmed%20to%20ABC%20News.
- https://www.nytimes.com/2025/01/13/briefing/childhood-vaccinations-trump.html
- https://www.nytimes.com/2025/03/25/health/measles-kennedy-vitamin-a.html
- https://www.opb.org/article/2025/03/29/covid-vaccine-skepticism-is-affecting-pandemic-prep/