Understanding the Impact of Vaccines on Public Health
Written on
The Role of Vaccines in Preventing Disease
As the editor of the History of Vaccines, a project by the College of Physicians of Philadelphia, I frequently encounter intriguing questions. Recently, a university employee raised a concern regarding the connection between COVID-19 vaccinations and ongoing infections. Specifically, she asked why the vaccines are deemed effective if vaccinated individuals still contract the virus. This question reveals a misunderstanding of how vaccines function.
One significant issue with this line of questioning is the Nirvana Fallacy, which suggests that if something isn’t entirely effective, it’s deemed worthless. This reasoning often surfaces regarding the flu vaccine: “It’s only 40% to 60% effective, so why should I bother?” The truth is, that level of effectiveness can have a substantial impact. If half the people who would typically fall ill, miss work, or incur medical expenses could avoid these consequences, the savings in resources and productivity would be immense.
Next, it’s essential to differentiate between infection and disease. When a virus infects me, it means it has begun to replicate. However, if I’ve been vaccinated or previously infected, my body is equipped with antibodies and specialized cells that can combat the virus swiftly, often before I even notice symptoms. Occasionally, vaccinated individuals may experience mild symptoms from infections like measles, a phenomenon referred to as “modified measles.” Importantly, these individuals tend to be less contagious, even though measles is highly infectious.
Those who recover from an infection before developing symptoms often go unrecognized. Without symptoms, there’s no reason to seek medical attention, leading to a lack of testing and, consequently, no recorded cases.
So, does this imply that polio is still present? Not exactly, but it remains a potential threat. If vaccination efforts ceased, polio could re-emerge due to its high transmissibility. Although measles has been effectively eliminated in the U.S., outbreaks continue to occur primarily in unvaccinated communities.
Furthermore, if many individuals in an outbreak are vaccinated, it doesn’t indicate that the vaccine is ineffective; rather, it reflects a misunderstanding of mathematical probabilities.
Addressing Misconceptions About COVID-19 Hospitalization
I also received an inquiry regarding COVID-19 hospitalization rates. A reader questioned why hospitalizations are reported for individuals admitted for other reasons who later test positive for COVID-19. This notion implies that data might be manipulated, but that’s not entirely accurate. Even if some hospitalizations are coincidental, the higher rate of unvaccinated individuals among hospitalized patients is significant. This suggests that either unvaccinated people are more prone to hospitalization for various ailments or that vaccinated individuals are less likely to be hospitalized for COVID-19.
The implication here raises questions about the overall health of the unvaccinated. This challenges the notion that a healthy lifestyle negates the need for vaccination. In reality, refusing vaccination in the current climate could lead to poor health outcomes.
With the prevalence of misinformation surrounding science and technology, especially via social media, it's easy to see why confusion exists. While reliable information is available online, it often lacks excitement compared to the sensational narratives that capture our attention. As a result, many individuals gravitate towards narratives filled with peril and conspiracy, rather than factual knowledge.
As I strive to remain patient with inquiries that may seem accusatory, I must remind myself that not everyone has had the same educational opportunities I have. Many public schools are moving away from teaching essential scientific concepts, which can lead to misunderstandings about critical health issues.
It's a disheartening reality, but one we must acknowledge.
Thanks!
René F. Najera, MPH, DrPH, is a public health expert, epidemiologist, and an avid runner, cyclist, and swimmer. He works at a local health department in Virginia and teaches at a university in northern Virginia. His views are his own and do not necessarily reflect those of his employers or associates.