reinfektálódás
Reinfektálódás refers to the process where an individual becomes infected with a pathogen again after having previously recovered from an infection with the same pathogen, or having been vaccinated against it. This can occur for several reasons. One common cause is the emergence of new strains or variants of the pathogen that are not sufficiently recognized by the immune system developed from the previous infection or vaccination. This is particularly evident with rapidly mutating viruses like influenza and coronaviruses. Another factor is the waning of immunity over time. The antibodies and cellular immune responses generated after infection or vaccination can decrease in effectiveness, leaving the individual more susceptible to reinfection. Furthermore, the initial infection might not have conferred complete or lifelong immunity, allowing the pathogen to re-establish itself. The severity of a reinfection can vary significantly, ranging from asymptomatic or mild illness to a more severe presentation, depending on factors such as the specific pathogen, the individual's immune status, and the characteristics of the new exposure. Understanding reinfektálódás is crucial for public health strategies, including the development of updated vaccines and the implementation of preventive measures.