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How have vaccines helped prevent viral infections?
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infectious disease
Birds are the primary reservoirs of West Nile virus. The virus is transmitted to humans and horses by mosquitoes that have bitten infected birds.
Vaccines prevent viral infections by imitating a natural infection, which prompts the immune system to produce antibodies and build immunological memory. This process ensures that if the body encounters the actual virus in the future, it can recognize and fight the pathogen before it causes serious illness.123
Vaccines utilize various methods to stimulate this protective response:
- Live attenuated vaccines: Use weakened forms of the virus that mimic natural infection to produce strong, long-lasting immunity.143
- Inactivated vaccines: Use viruses killed by heat or chemicals to elicit an immune response, though they often require larger quantities or boosters.42
- Subunit and Recombinant vaccines: Use specific viral proteins or genetic material to trigger immunity without using the live virus, making them safer for certain populations.143
- mRNA vaccines: Use messenger RNA to instruct cells to produce viral proteins, which then stimulate the immune system.14
Because viral infections do not respond to antibiotics, vaccines provide a critical defense, having successfully led to the global eradication of smallpox and significant declines in diseases like polio.53