Public health insights and vaccine science.
The COVID-19 pandemic accelerated a technology that had been in development for decades: mRNA vaccines. Unlike traditional vaccines that use weakened or killed pathogens, mRNA vaccines deliver genetic instructions that teach your cells to produce a harmless piece of the target pathogen, triggering an immune response. The implications extend far beyond COVID — mRNA technology is now being applied to influenza, RSV, cancer therapeutics, and rare genetic diseases. The speed of development is transformative: once a pathogen's genetic sequence is known, an mRNA vaccine candidate can be designed in days and manufactured in weeks. This technology represents a fundamental shift in how we fight infectious disease, moving from a reactive model that takes years to a proactive one that can respond to emerging threats in real time.
Herd immunity occurs when a sufficient percentage of a population is immune to a disease — through vaccination or prior infection — that its spread becomes unlikely, protecting even those who cannot be vaccinated. The threshold varies by disease: measles requires about 95% immunity, while less contagious diseases may need 70-80%. This concept is crucial because some people genuinely cannot receive vaccines — infants too young for certain immunizations, individuals with compromised immune systems, and people with specific allergies to vaccine components. Their protection depends entirely on the immunity of those around them. When vaccination rates drop below herd immunity thresholds, these vulnerable individuals are the first to suffer.