Throughout the history of medicine, few tools have transformed our life expectancy and quality of life as profoundly as vaccines. Considered the cornerstone of preventive medicine in both humans and animals, these preparations have a clear mission: to train our immune system to recognize and fight pathogens before the danger becomes real.
Although vulnerability to certain diseases can be studied through a DNA test, many of them do not currently have vaccines available. Nevertheless, vaccination has helped save millions of lives in the face of epidemics and common diseases, such as the flu.
How does a vaccine work?
A vaccine is, essentially, guided training for your body's defenses.
To achieve this, an agent that mimics the disease-causing microorganism is introduced into the body. This can be an attenuated or inactivated microorganism, small fragments derived from it, or genetic instructions that allow our own cells to produce it (mRNA vaccines). Being weakened or incomplete, this pathogen does not cause the disease, but it does accomplish a key goal:
- The immune system detects this element as foreign (antigen).
- An immediate, coordinated defensive response is triggered, involving highly specialized cells.
- Specific antibodies tailored to fight it are produced, along with immunological memory cells that enable a swift and effective response upon future exposure to that pathogen.
Immunological memory
The true power of vaccines lies in immunological memory. When a pathogen first encounters the immune system, mounting a response takes several days. However, our immune system keeps detailed "notes" of what occurred.
Thanks to this biological record, if you are exposed to the actual pathogen in the future:
- Ultra-fast, specific response: Your immune system identifies it almost instantly.
- Effective neutralization and elimination: Large amounts of antibodies are rapidly deployed, and specialized defense cells are activated before the microorganism has time to multiply and cause severe damage.
For this reason, getting vaccinated makes all the difference: even when an infection cannot be entirely prevented, a trained body significantly reduces the severity of the disease and the risk of complications.
A historic milestone saving millions of lives
Vaccines are recognized as one of the most effective, cost-efficient, and impactful public health interventions in history. In fact, they are directly responsible for controlling and even eradicating threats that once decimated entire populations:
- Historic eradication: Smallpox in humans and rinderpest in cattle were declared eradicated in 1980 and 2011, respectively.
- Global control and reduction: Polio, measles, yellow fever, and diphtheria, among others.
- Ongoing protection and prevention: Hepatitis B, tetanus, whooping cough (pertussis), and rabies.
Vaccines and genetics
Today, laboratories are not only working on optimizing vaccines against common viruses and bacteria, but also on a revolutionary frontier: developing vaccines targeting complex and neurodegenerative disorders, such as Alzheimer's disease or Parkinson's disease, as well as cancer vaccines.
In this paradigm, personal genetics can play a crucial role. Knowing beforehand your genetic predisposition to health conditions and specific health biomarkers will allow healthcare professionals to:
- More accurately identify individuals who are more susceptible to developing certain complex diseases.
- Personalize preventive strategies and identify who could benefit most from new therapeutic or preventive vaccines currently under development.
The effectiveness of vaccines is undeniable: they train our bodies against potential threats and save millions of lives every year. Combining this powerful tool with insights into our own DNA brings us closer every day to truly personalized, predictive, and preventive medicine.
