👉 Unable-to-infect (AUI) infections occur when an individual who should be immune to a pathogen fails to mount an effective immune response, often due to underlying conditions such as immunosuppression, genetic disorders, or certain medications. This failure can result from a weakened immune system that cannot produce sufficient antibodies or activate immune cells to combat the invading microorganism. For example, individuals with HIV/AIDS, those undergoing chemotherapy, or those with primary immunodeficiencies are particularly susceptible to AUI infections. These infections highlight the critical role of a robust immune system in preventing pathogens from establishing themselves and causing disease, and they underscore the importance of managing conditions that compromise immunity to prevent such complications.
