breakthrough infections

Breakthrough infections occur when a person who is vaccinated against a disease still contracts it. While vaccines are highly effective at preventing illness, they don’t provide 100% protection. Factors like the amount of virus exposure, individual immune response, and new variants can influence the chance of infection. Usually, vaccinated individuals experience milder symptoms and are less likely to spread the disease. Breakthrough cases highlight that vaccines are an important tool for reducing severe illness and transmission, but some risk of infection remains, especially as the virus evolves.